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1
Icoz, Dilsad. "Milimeterwave Fmcw Radar Design". Master's thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/3/12611385/index.pdf.
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In traffic radar system, Frequency Modulated Continuous Wave (FMCW) will be used since these radars are preferred in short distance and high range resolution systems.
The system to be constructed is not only a system operating with Doppler principle and detection of speedon the contrary a functional radar is planned to be produced. In various traffic radars in use, Doppler shift constituted by the targets causing high reflection within detection field is measured and the measured speed corresponding to this shift is seen to exceed the limits. In case of cars more than one, their speeds cannot be measured separately. In this FMCW Radar system, it is possible to identify the targets&rsquo
distance and speed. The speed information of the target will be specified by Doppler frequency and also as a result of position monitoring, the speed will be determined out of the position change occurring in the unit time. These features, in multi lane road, will be used both for different lanes and also for the cars moving at the same lane but in different ranges. The radar system designed in this study is an easy to use, low power consuming device which can be mounted into the car. Only the active part of the system is off the shelf products and the other RF cards are designed and produced. As a result, a low cost traffic radar will be produced
2
Vural, Aydin. "Fmcw Radar Altimeter Test Board". Master's thesis, METU, 2003. http://etd.lib.metu.edu.tr/upload/2/1219526/index.pdf.
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In this thesis, principles of a pulse modulated frequency modulated continuous wave radar is analyzed and adding time delay to transmitted signal in the laboratory environment performed. The transmitted signal from the radar has a time delay for traveling the distance between radar and target. The distance from radar to target is more than one kilometers thus test of the functionality of the radar in the laboratory environment is unavailable.
The delay is simulated regarding to elapsed time for the transmitted signal to be received. This delay achieved by using surface acoustic wave (SAW) delay line in the laboratory environment. The analyses of the components of the radar and the delay line test board are conducted.
3
Eriksson, Oscar. "Filterdesign och hårdvarukonstruktion för FMCW-radar". Thesis, Linköping University, Department of Electrical Engineering, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-7988.
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Den här högskoleavhandlingen beskriver designen av ett IF-filter samt hårdvarukonstruktion av en ny 77 GHz FMCW-radar demonstrator. Syftet med demonstratorn är att illustrera hur kisel germanium-, SiGe, teknologi kan användas istället för den mer vedertagna men dyrare gallium arsenik-, GaAs, teknologin. Den gamla radar-prototypen vilken Acreo AB utvecklat är funktionell men behöver konstrueras om för att bättre kunna utvärdera radarprestandan. I avhandlingen presenteras grundläggande radarteori och ekvationer för att underlätta förståelsen av de olika systemblocken. Rapporten beskriver också systemarkitekturen och hur dess funktionalitet kommer att testas. Det omdesignade IF-filtret har simulerats i en PSpice-simulator och ett prototypkort av detta har tillverkats för mätningar. Ett 4-lagers kretskort av hela systemet har tagits fram i Orcad Layout. Slutligen innehåller rapporten förslag på förbättringar till nästa demonstratorversion.
This bachelor thesis describes the design of an IF-filter and the hardware construction of a new version of a 77 GHz FMCW-radar demonstrator. The purpose of the demonstrator is to illustrate how the silicon germanium-, SiGe, technology could be used instead of the more conventional but also much more expensive gallium arsenide-, GaAs, technology. The old radar prototype that Acreo AB has developed is fully functional but needs to be redesigned to be able to evaluate the radar performance in a better way. The thesis presents the basic radar theory and equations to help understanding the construction of the system blocks. The report also describes the system architecture and how its functionality should be tested. The redesigned IF-filter has been simulated in a PSpice simulator and a prototype has been manufactured and measured. A 4-layer PCB-board of the whole system was done in Orcad Layout. Finally the report is concluded with suggestions on improvements for the next demonstrator version.
4
Chen, Hung-Ruei. "FMCW radar jamming techniques and analysis". Thesis, Monterey California. Naval Postgraduate School, 2013. http://hdl.handle.net/10945/37597.
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Approved for public release; distribution is unlimitedFrequency-Modulated Continuous-Wave (FMCW) radar is a type of Low Probability of Intercept radar system that is being heavily investigated in the military. Not only is its transmission difficult to be detected by enemy intercept receivers, but FMCW radar has the inherent capability of increasing coherent signal power while suppressing noise power during its receive signal processing. This thesis investigates the jamming effectiveness of selected jamming waveforms by injecting the interfering signals into the Lab-Volt Radar Training System (LVRTS). The jamming effect is evaluated based on the change in beat frequency due to the jamming. Due to the hardware limitations of the LVRTS, a MATLAB simulation model is also constructed for advanced electronic attack testing. The MATLAB model emulates the FMCW emitter digital signal processing response to coherent and non-coherent jamming signals under an anti-ship capable missile scenario. The simulation output is the target range and range rate, whose error measures quantify the jamming effectiveness. From the standpoint of electronic warfare, related subjects such as electronic warfare support measures and FMCW electronic protection are also discussed.
5
Zhang, X. "Modelling of FMCW ground penetrating radar". Thesis, University of Bath, 1997. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.760700.
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Bas, Alon. "An ultra high resolution FMCW radar". Master's thesis, University of Cape Town, 1992. http://hdl.handle.net/11427/8357.
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Bibliography: leaves 127-128.There is a great need for real-time non-intrusive measurements in industry. A short-range radar system can be used to make these measurements. A standard requirement for these type of applications is high resolution. This is a standard problem in radar. Using classical signal processing techniques, the range resolution is proportional to the bandwidth of the transmitted signal. This poses a serious problem in radar as very large bandwidths are required - typically lSOGHz for 1 mm range resolution. Alternative techniques have been sought which do not rely on large transmitted bandwidths, but which rely on large signal-to-noise ratio (SNR). Such techniques exist in modem spectral analysis eg. auto-regressive techniques. These techniques model the data. In other words, they assume a priori information. Linear frequency-modulated continuous-wave (FMCW) radar was utilized, since a pulsed radar would require very precise time measurements due to the short range (a few ns). The FMCW radar would have to be very linear for the modelling process to work properly. The frequency domain measurement of the received system data would then be proportional to range. An FMCW radar system was built and tested. The modem signal processing techniques were found to work well when injected with sinusoidal signals from signal generators. The hardware was also found to perform satisfactorily. However, amplitude modulation was observed in the mixing process and subsequently, the modelling process did not perform satisfactorily when interfaced to the hardware. Due to the amplitude modulation problem, two closely-spaced targets disrupted the high resolution properties of the modelling process. Nevertheless, a single target could be resolved within a resolution bin of better than 1 cm. A solution is proposed in chapter eight, however, it is out of the scope of this thesis.
7
Mohd, Isa F. N. "Antenna system design for FMCW avalanche radar". Thesis, University College London (University of London), 2012. http://discovery.ucl.ac.uk/1356841/.
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Avalanches pose a significant threat to human life and settlements, hence their study is key in formulating settlement risk zones. Validating models of avalanches, developed to predict their behaviour, are limited by the quality of current field data. University College London (UCL) has developed a sophisticated FMCW phased array raday with sub-metre range resolution for imaging avalanches. The radar is installed in a bunker in an avalanche test facility in Valleé de La Sionne (VDLS) and has been gathering data since winter 2009. Due to space constraint and destructive issues with the bunker, a design for compact, low-cost and directive antenna is crucial to be used with the avalanche radar. This thesis documents the theory, analysis, design and measurement of the compact, low-cost and directive antennas. First, the parameter and location of VDLS is scrutinized to determine the characteristics that needs to be fulfilled when designing the antennas. Some of the parameters that were looked into are the operating frequency, the beamwidth of the antenna and the effects of placing the antenna in an array. Then, the study of the first antenna, a multilayer microstrip patch antenna with novel feeding method is presented. The directive concept of the antenna is obtained using an array of 4 x 2 patches, with increased antenna height and a novel feeding technique. The antenna is then fabricated using Rogers RT Duroid 5880 and assembled to be measured and compared with the simulated version. The second antenna proposed in this thesis is an array of microstrip Yagi antenna. The directive concept of this antenna is achieved through the design of the microstrip Yagi antenna itself and applying the antenna in an array of linear arrangement. The antenna is then fabricated using Rogers RT Duroid 5880 and compared with the simulated version. Finally, the first antenna characteristics is being exploited in series of Matlab program to estimate the antenna performance in a sparsely-populated phased array system. It has been demonstrated experimentally and through measurement that the antenna system design is suitable for the application of FMCW avalanche radar.
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Zhu, Qizhao y Yaqi Wang. "FMCW radar implemented with GNU Radio Companion". Thesis, Linnéuniversitetet, Institutionen för fysik och elektroteknik (IFE), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-52985.
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Continuous-wave frequency-modulated radar, or FMCW radar, is simple in design, small in size and weight and uses low transmitting power. The range resolution depends on the bandwidth. FMCWradar is used in applications ranging from guided weapons systems to vehicle collision avoidance systems. Measuring the distance to the target is the essential feature of FMCW radar. Firstly, this thesis introduces the basic structure of the FMCW radar and the principle formeasuring distance. Secondly, by using software-dened radio (SDR),FMCW radar can be implemented and congured with a reduced costand complexity. In this report, the radar is implemented by means ofthe software GNU Radio Companion with a test signal. HackRF may be used in future work with an osmocom source instead of the testsignal.
9
Carlsson, Andreas. "Vindjämförelse mellan VAD-algoritm och FMCW-radar". Thesis, Uppsala universitet, Institutionen för geovetenskaper, 1998. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-392767.
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I denna undersökning som mestadels koncentrerat sig på VAD-algoritmen och dess fördelar och nackdelar har till att börja med två för algoritmen särdeles viktiga parametrar undersökts. Totala antalet VAD-cirklar respektive andelen av dessa som i slutänden ger en vind som resultat har direkt studerats som en funktion av tiden och samtidigt indirekt mot de synoptiska väderförhållanden som rådde vid tidpunkten i fråga. Som en andra del av arbetet utfördes en mestadels relativ jämförelse där två till viss del olika radaralgoritmer jämfördes i samband med olika vädersituationer och olika tider på dygnet. Vad det gäller totala antalet cirklar visade sig en god korrelation mot det storskaliga vädret vilket främst kunde ses i samband med frontpassager medan ingen typ av regelbunden dygnsvariation kunde ses. Andelen cirklar som i slutänden gav godkänd vind som resultat visade istället en starkt regelbunden dygnskorrelation medan enbart en ytterst svag korrelation med vädret kunde ses. Den följande jämförelsen visade på två intressanta resultat i samband med natt- respektive dagmätningar samt mätningar utförda vid två högtryckssituationer. Den första jämförelsen visade på en markant större skillnad i mätresultat i samband med nattliga mätningar än vid mätningar i liknande vädersituationer utförda dagtid. Sammankopplat med resultatet som gavs i samband med andelen resultatgivande cirklar antyder detta att VAD-algoritmen i samband med nattliga mätningar ger ett relativt inkorrekt resultat. Ett andra intressant resultat gavs i det visade sig finnas en signifikant skillnad i resultaten vid de jämförelsen mellan resultaten från mätningarna utförda vid de två ovan angivna högtryckssituationerna.
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Ash, M. "FMCW phased array radar for imaging snow avalanches". Thesis, University College London (University of London), 2013. http://discovery.ucl.ac.uk/1383579/.
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Radar has emerged as a useful tool for measuring avalanches to improve our knowledge of their behaviour. These measurements are used to refine and validate mathematical models of avalanches which are employed in the calculation of avalanche risk zones. However, current radar measurements do not provide a true representation of an entire avalanche flow due to their inadequate range resolution and lack of cross-range resolution. This thesis describes the development of an FMCW phased-array radar for use as a research tool to enable 2-D field measurements of avalanches in unparalleled detail. The design of the radar is presented in detail based on a review of the current avalanche remote sensors and applicable radar literature. The radar operates at 5.3GHz to illuminate dense centimetre-size blocks of snow. It is shown that the developed radar has a range resolution of 1.3m following processing, a 19x gain over other avalanche radar, and is sensitive to snow movements beyond 2.5km, sufficient to measure an entire avalanche flow. Additionally, methods of processing the radar data are developed. These include MTI processing using an IIR filter, avalanche front detection using OS-CFAR, and cohering of the array using low-quality phase synchronising sources within the field-of-view of the radar. The radar is now deployed in a bunker at well-equipped avalanche test site in Switzerland where it automatically records naturally occurring avalanches. This thesis describes two avalanches which were recorded by the radar during the 2010/11 winter. The collected data has been processed using the aforementioned processing techniques. The processing outputs are presented including single channel range-time images, velocity measurements of the avalanche fronts, and detailed 2-D images of the avalanches showing unprecedented detail. It is shown that there is the potential to extract velocity measurements of individual blocks of snow comprising the avalanche.
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Stofberg, Anneke. "IQ reflected power canceller for an FMCW radar". Thesis, Stellenbosch : Stellenbosch University, 2014. http://hdl.handle.net/10019.1/86640.
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Thesis (MEng)--Stellenbosch University, 2014.ENGLISH ABSTRACT: Large close range environmental reflections or poor isolation between the transmit and receive paths of an FMCW radar can overload the receiver. The In phase and Quadrature phase (IQ) Reflected Power Canceller (RPC) provides a solution to the problem by cancelling any close range reflections. In this study a procedure to optimise the design of an RPC is developed and the performance limits of a practical RPC is investigated in depth. There are four focus areas in the evaluation and design of the IQ Reflected Power Canceller. First, an analysis was performed on a theoretical IQ Reflected Power Canceller, which provided insight into how the system functioned and made it possible to identify practical application issues that would arise during the design. The next focus area was the IQ Reflected Power Canceller’s dynamic range. Equations, based on the power and noise characteristics of each component in the canceller, were derived. From these equations, a system, with an optimised dynamic range, could be developed. Next, the IQ Reflected Power Canceller’s feedback loop stability was investigated. The canceller is an active negative feedback control system but, in order to obtain the negative feedback, the feedback signal has to be phase shifted by 180 degrees to the phase of the input signal. An analysis of the canceller’s RF phase contribution resulted in an equation that can be used to manage the nett RF phase in the feedback loop. The evaluation model of the IQ Reflected Power Canceller produced favourable results. The tests performed on the system included measuring the level of cancellation that can be achieved, whether the dynamic range corresponds to the predicted values and the amount of RF phase error that can be introduced in the feedback path while maintaining a stable system. The IQ Reflected Power Canceller was found to perform well in the evaluation. It provided a cancellation of more than 45 dB for close range reflections and the canceller remained stable across a wide range of RF centre frequencies (1 GHz). This means that the FMCW radar’s frequency modulation bandwidth will not be limited because of the IQ Reflected Power Canceller. The evaluation clearly showed that the modulator in the feedback loop is the critical element that determines the dynamic range of the radar with an RPC.
AFRIKAANSE OPSOMMING: Onvoldoende isolasie tussen die sender en ontvanger van ’n Frekwensie Gemoduleerde Kontinu Golf radar, sowel as groot weerkaatsings vanaf voorwerpe in die omgewing van die radar, veroorsaak dat die ontvanger versadig. Hierdie beperking veroorsaak dat die radar ’n verminderde dinamiese bereik het, en daarmee ook dat die radar se maksimum teiken-afstand verminder word. Die IQ Gereflekteerde Drywingskanselleerder kan as ’n oplossing gebruik word teen hierdie ongewenste refleksies. Hierdie navorsing poog om ’n kanselleerder te evalueer met die eind doel gestel daarop om ’n praktiese stelsel aanmekaar te sit. Die kanselleerder word geëvalueer deur na vier fokus areas te kyk. Eerstens word ’n ideale model opgestel, wat ’n beter begrip van die kanselleerder bewerkstellig. Uit hierdie ideale model, is daar praktiese oorwegings wat die kanselleerder affekteer, geïdentifiseer. Ten einde die dinamiese bereik van die radar ontvanger te verbeter, word ’n metode afgelei wat gebruik word om die kanselleerder se dinamiese bereik te optimeer. Hierdie metode neem die maksimum drywingsbeperkinge van die komponente in die kanselleerder in ag. Die kanselleerder is ’n aktiewe terugvoer beheerstelsel, en aangesien ’n sommeerder in die terugvoer lus gebruik word, moet die fase deur die lus met 180 grade geskuif word om sodoende ’n kansellerende sein by die ontvangde sein te tel. Die RF fase foute in die kanselleerder word geanaliseer deur ’n nie-ideale model van die kanselleerder op te stel. Hierdie nie-ideale model maak dit moontlik om die effek van ’n RF fase fout op die kanselleerder se stabiliteit te ondersoek. ’n Praktiese kanselleerder is ontwerp uit die inligting wat versamel is gedurende die evaluasie, en ’n werkende stelsel is aanmekaar gesit. Met hierdie praktiese kanselleerder is die hoeveelheid drywing-onderdrukking wat bereik kan word, gemeet. Die dinamiese bereik van die kanselleerder is ook bepaal en vergelyk met die teoreties berekende waardes. Die aannames oor die effek van die RF fase fout in die kanselleerder, is bevestig deur metings te neem. Goeie resultate is met die kanselleerder behaal. ’n Kansellasie van meer as 45 dB is gemeet vir naby-geleë refleksies. Die kanselleerder het ook stabiel gebly oor ’n wye band van senter-frekwensies (1 GHz). Dus sal die Frekwensie Gemoduleerde Kontinu Golf radar se modulasie bandwydte nie beperk word as gevolg van die kanselleerder nie. Uit die evaluasie is daar gevind dat die modulator die kritieke element in the kanselleerder se terugvoer lus is, dus bepaal die modulator die dinamiese bereik van die radar met ’n kanselleerder.
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Zhang, Ao. "Object Detection from FMCW Radar Using Deep Learning". Thesis, Université d'Ottawa / University of Ottawa, 2021. http://hdl.handle.net/10393/42512.
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Sensors, as a crucial part of autonomous driving, are primarily used for perceiving the environment. The recent deep learning development of different sensors has demonstrated the ability of machines recognizing and understanding their surroundings.
Automotive radar, as a primary sensor for self-driving vehicles, is well-known for its robustness against variable lighting and weather conditions. Compared with camera-based deep learning development, Object detection using automotive radars has not
been explored to its full extent. This can be attributed to the lack of public radar datasets.
In this thesis, we collect a novel radar dataset that contains radar data in the form of
Range-Azimuth-Doppler tensors along with the bounding boxes on the tensor for dynamic road users, category labels, and 2D bounding boxes on the Cartesian Bird-EyeView range map. To build the dataset, we propose an instance-wise auto-annotation algorithm. Furthermore, a novel Range-Azimuth-Doppler based multi-class object detection deep learning model is proposed. The algorithm is a one-stage anchor-based detector that generates both 3D bounding boxes and 2D bounding boxes on Range-AzimuthDoppler and Cartesian domains, respectively. Our proposed algorithm achieves 56.3% AP with IOU of 0.3 on 3D bounding box predictions, and 51.6% with IOU of 0.5 on 2D bounding box predictions. Our dataset and the code can be found at https://github.com/ZhangAoCanada/RADDet.git.
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Raimundo, Xavier Zage. "FMCW signals for radar imaging and channel sounding". Thesis, Durham University, 2015. http://etheses.dur.ac.uk/11205/.
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A linear / stepped frequency modulated continuous wave (FMCW) signal has for a long time been used in radar and channel sounding. A novel FMCW waveform known as “Gated FMCW” signal is proposed in this thesis for the suppression of strong undesired signals in microwave radar applications, such as: through-the-wall, ground penetrating, and medical imaging radar. In these applications the crosstalk signal between antennas and the reflections form the early interface (wall, ground surface, or skin respectively) are much stronger in magnitude compared to the backscattered signal from the target. Consequently, if not suppressed they overshadow the target’s return making detection a difficult task. Moreover, these strong unwanted reflections limit the radar’s dynamic range and might saturate or block the receiver causing the reflection from actual targets (especially targets with low radar cross section) to appear as noise. The effectiveness of the proposed waveform as a suppression technique was investigated in various radar scenarios, through numerical simulations and experiments. Comparisons of the radar images obtained for the radar system operating with the standard linear FMCW signal and with the proposed Gated FMCW waveform are also made. In addition to the radar work the application of FMCW signals to radio propagation measurements and channel characterisation in the 60 GHz and 2-6 GHz frequency bands in indoor and outdoor environments is described. The data are used to predict the bit error rate performance of the in-house built measurement based channel simulator and the results are compared with the theoretical multipath channel simulator available in Matlab.
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Svensson, Johan. "High Resolution Frequency Estimation in an FMCW Radar Application". Thesis, Linköpings universitet, Reglerteknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-148526.
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FMCW radars are widely used in the process industry for range estimation, usu- ally for estimating the liquid level in a tank. Since the tank system, often is an automatically controlled system, reliable estimates of the surface level are re- quired, e.g. to avoid the tank from pouring over or become empty. The goal of this thesis is to investigate methods which can distinguish fre- quencies closer to each other than the FFT resolution limit. Two properties are of interest, the accuracy and the resolution performance. Three such methods have been evaluated: one that tries to compensate for the leakage and interference of close frequencies, one subspace-based method and one deconvolution method. The deconvolution is performed with the iterative Lucy Richardson algorithm. The methods are evaluated against each other and against a typical FFT based algorithm. The methods sensitivity to amplitude differences is examined together with the robustness against noise and disturbances which appear due to imperfections in the radar unit. The deconvolution algorithm is the one that performs the best. The subspace-based method SURE requires prior knowledge of the number of ingoing frequencies which is difficult to know for real data from an FMCW radar. The leakage compensation method main weakness is the influence of the phase difference between close frequencies. The deconvolution algorithm is evaluated on some real data, and it is proven that it has better resolution performance than the FFT. However, the accuracy of the estimates are dependent on the number of iterations used. With a large num- ber of iterations, the algorithm finds peaks with small amplitude nearby the large peaks and they will thus interact and hence contribute to a worse accuracy even in the undisturbed case. If too few iterations are used in the deconvolution algo- rithm the resolution performance is about the same as the FFT algorithm. With a suitable choice of iterations about 40–50 mm, extra of continuous measurements are achieved. However, the estimation error of the gained resolution can in the worst case be about 40–50 mm.
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Kurt, Sinan. "Range Resolution Improvement Of Fmcw Radars". Master's thesis, METU, 2007. http://etd.lib.metu.edu.tr/upload/12608808/index.pdf.
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Frequency Modulated Continuous Wave (FMCW) radar has wide application areas in both civil and military use. The range resolution is a critical concept for these FMCW radars as for the other radar types. There are theoretical restrictions in the range resolution. In addition, the non-ideal properties of the modules used in the systems negatively affects the range resolution. The transmitter leakage, non-linear frequency sweep, FM to AM distortion and measurement errors are some of the critical non-ideal properties. The problems arising from these non-ideal properties further restrict the range resolution of FMCW radars. Another important concept for the range resolution that can be obtained from FMCW radars is the signal processing method. This thesis deals with the non-ideal properties of the system modules and techniques to reduce their effects on the range resolution. Furthermore, the signal processing methods used for FMCW radar signals and the possible improvement techniques for these methods are discussed. Moreover, a simple signal processing unit called zero crossing counter which can be used for short range FMCW radars is implemented and range resolution performance of this zero crossing counter is investigated by carrying out measurements on a prototype FMCW radar at 2200MHz.
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Ernst, Robert. "Vital Sign Radar : Development of a Compact, Highly Integrated 60GHz FMCW Radar for Human Vital Sign Monitoring". Thesis, Högskolan i Halmstad, Akademin för informationsteknologi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-31496.
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Supervision of human vital signs has always been an essential part in healthcare. Nowadays there is a strong interest in contact-less monitoring methods as they operate less static and offer higher flexibility to the people observed. Recent industrial development enabled radar functionality to be packed in single-chip solutions, decreasing application complexity and speeding up designs. Within this thesis, a vital sign radar prototype has been developed utilising a recently released 60GHz frequency modulated continous wave single-chip radar. The electronics development has been focused on compactness and high system integration. Special attention has been given to the onboard analogue signal filtering and digital data preprocessing. The resulting prototype radar is then tested and evaluated using test scenarios with increasing difficulty. The final experiments prove that the radar is capable of tracking human respiration rate and heartbeat simultaneously from a distance of 1m. It can be concluded that modern radar devices may be significantly miniaturised for e.g. portable operation while offering a wide variety of application possibilities including vital sign monitoring.
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Bleh, Daniela [Verfasser] y Oliver [Akademischer Betreuer] Ambacher. "W-Band FMCW MIMO radar demonstrator system for 3D imaging". Freiburg : Universität, 2017. http://d-nb.info/1143602803/34.
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FREITAS, João Mario Mendes de. "Sensor de nível por micro-ondas e tecnologia RADAR-FMCW". reponame:Repositório Institucional da UNIFEI, 2013. http://repositorio.unifei.edu.br/xmlui/handle/123456789/922.
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Este trabalho apresenta o desenvolvimento de um protótipo de medidor de nível para tanques e silos que utiliza a tecnologia radar na faixa de micro-ondas de 2,5 GHz modulado em frequência FMCW, para melhor entendimento quanto ao funcionamento dos dispositivos comerciais semelhantes. O equipamento foi desenvolvido a partir do estudo das características relacionadas à modulação, amplificação, transmissão, recepção, demodulação, com o objetivo de se conhecer mais profundamente a propagação das ondas eletromagnéticas na faixa de micro-ondas e a influência do meio para o seu funcionamento. Aborda-se a evolução histórica da tecnologia do radar aplicada aos sensores de nível, apresentando dispositivos semelhantes permitindo a visualização das vantagens na medida de nível em cada um deles. O trabalho também descreve a importância da aplicação deste dispositivo em silos, tanques e/ou processos industriais onde a medição deve ser sem contato físico com o produto, observando as exigências de cada meio de propagação. É apresentado o desenvolvimento teórico, com as características de cada módulo do sensor. O desempenho dos módulos do protótipo foi avaliado comparando valores previamente calculados com dados obtidos através de testes práticos em laboratório.
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Tchekashkin, Ivan. "Design and implementation of a low-cost FMCW imaging radar". Master's thesis, University of Cape Town, 2016. http://hdl.handle.net/11427/24299.
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Imaging radar systems have been predominantly developed using a coherent pulse radar approach, which is typically associated with expensive and complex hardware that usually requires a large amount of space. Hence, the use of such sensors is reserved to large organizations that can afford to purchase or develop them. This is unfortunate as there are numerous uses for imaging radar sensors in both military and civilian sectors. One of such uses lies in the agricultural sector and entails using imaging radar data to monitor crop development. As a result, a project was initiated at the University of Cape Town (UCT), in collaboration with droneSAR company, which aimed to develop a low-cost, compact, imaging radar that could be mounted on a small Unmanned Aerial Vehicle (UAV). The purpose of this research project is aimed at developing the first system prototype. The RadioCamera-S is the S-band FMCW radar, that was developed to test the architecture that could be utilised to enable the filtering of the feed-through and nadir components, which are typically the strongest returns in the spectrum. The prototype has two modes of operation that are aimed at shifting the unwanted signals outside of the pass band of the receiver. This is achieved by generating two identical L-FMCW waveforms that are offset by a chosen time period. This enables a shift of the spectrum by the frequency, which corresponds to the time offset. The capabilities of the proposed hardware were examined and the specifications for the ground based version were developed. The parameters that influence the wave-form design were discussed and the optimal values were chosen for the ground based radar system. Verification of the transmitter and receiver operation was carried out, which was followed by system tests that demonstrated that the feed-through signal could be attenuated by employing the first proposed mode of operation. RTI plots were generated and showed that the radar was capable of detecting the movement of a reflector in the observable scene.
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Cassidy, Scott L. "Millimetre-wave FMCW radar for remote sensing and security applications". Thesis, University of St Andrews, 2015. http://hdl.handle.net/10023/7856.
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This thesis presents a body of work on the theme of millimetre-wave FMCW radar, for the purposes of security screening and remote sensing. First, the development of an optimised software radar signal processor will be outlined. Through use of threading and GPU acceleration, high data processing rates were achieved using standard PC hardware. The flexibility of this approach, compared to specialised hardware (e.g. DSP, FPGA etc…), allowed the processor to be rapidly adapted and has produced a significant performance increase in a number of advanced real-time radar systems. An efficient tracker was developed and was successfully deployed in live trials for the purpose of real-time wave detection in an autonomous boat control system. Automated radar operation and remote data telemetry functions were implemented in a terrain mapping radar to allow continuous monitoring of the Soufrière Hills volcano on the Caribbean island of Montserrat. This work concluded with the installation of the system 3 km from the volcano. Hardware modifications were made to enable coherent measurement in a number of existing radar systems, allowing phase sensitive measurements, including range-Doppler, to be performed. Sensitivity to displacements of less than 200 nm was demonstrated, which is limited by the phase noise of the system. Efficient compensation techniques are presented which correct for quadrature mixer imbalance, FMCW chirp non-linearity, and scanner drive distortions. In collaboration with the Home Office, two radar systems were evaluated for the stand-off detection of concealed objects. Automatic detection capability, based on polarimetric signatures, was developed using data gathered under controlled conditions. Algorithm performance was assessed through blind testing across a statistically significant number of subjects. A detailed analysis is presented, which evaluates the effect of clothing and object type on detection efficiency.
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Rygh, Martin. "Realization of a DDS/PLL Signal Source for W-band Radar Applications : Automotive FMCW Radar". Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for elektronikk og telekommunikasjon, 2011. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-14082.
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This thesis presents a realization process, of how a programmable DDS/PLL signalsource were made suitable as an linear FMCW waveform generator for automotiveW-band radar applications. The dissertation describes the specific background theorythat were used to complete the implementation and substantiate the discoveries duringthe development process. Hence is an outline of FMCW basic properties, automotiveradar implementations, applied waveforms and the fundamental radar ambiguity functionpresented and threated. Moreover are vital background theory for basic FMCW designproblems presented, including degradation of range resolution due to loss of effectivebandwidth, nonlinearities in chirp modulation and limitations of the receiver resolution.Additionally is the inevitable problem of FMCW transceiver noise leakage briefly described, along with the general concept of choosing the right beat frequency for maximal FMCW sensitivity and maximal range-Doppler resolution. The specific circuit design is then presented, together with the full radar design which the signal source is intended for. The realization process starts with an initial test of circuit performance, seen in relation to the radar documentation and set the fundament for the further investigation and development. Hence does this part include measurements and discussion of output power achievements, spectral purity, spectral waveform appearance and phase noise. The thesis does then set further focus to more specific methods of measuring and evaluating the circuits LFM waveform, in aspect of a combined frequency and time characterization, chirp linearity achievements and waveform beat frequency evaluation. The dissertation does further describe how the first hand waveform generation were erroneous and how this problem was investigated and solved through radar documentation/source code corrections. As a last part of the realization process is then the final and successive implementation of waveforms described, along with the main results presented as waveform spectrograms and selected beat frequency spectrum plots. The working process and the main results are then summarized in a final summary discussion. The major results and conclusions of the thesis are that the tested NORBIT DDS/PLLsignal source could be realized as an linear FMCW waveform generator with overallgood linear properties. Two basic LFM waveforms, the up-chirp and triangular waveformwere implemented and tested. However were there discovered nonlinearities withinthe up-chirp waveform, due to the transient response of the total circuit. Hence mostlikely caused by the limited PLL frequency lock time. This was proven through aspecific beat frequency analysis of the most affected waveform, with fitted W-band LFMcharacteristics. Nevertheless were the isolated chirp generation within the waveformsconsidered more than sufficient, since both windowing technics and selective samplingcould be used in the future radar implementation. Three specific waveform realizationswere specially recommended for the initial further use. Further were also a specific region of desirable waveform chirp-rates recommended, that enables a good trade off between close target radar sensitivity and digital acquisition system complexity. Additionally did the thesis work conclude with that the NORBIT signal source design, enabled a flexible and easy control of the waveform generation through the microcontroller interface. Further more had also the thesis work resulted in the implementation of two good methods for waveform measurements and analysis. By the use of the spectrogram- and the beat frequency-method, could accurate waveform properties be extracted. Hence were also these methods recommended for further waveform developments in the experimental radar project.Furthermore was it recommended that future effort should be put in to the developmentof more applicable waveforms, to achieve full multiple range-Doppler target extraction.Hence since the overall signal source proved to have the nessesary waveform agility.It was in addition proposed that the future full radar implementation should utilizethe accessabillity of the microcontroller to achieve synchronization of signal sourcemodulation and future sampling solution. Thus to enable beneficial beat frequencysampling for the quadrature radar receiver. Since the mapping of the phase noiseinfluence and the chirp linearity were seen as non-optimal, was it additionally suggested that future studies should yield better methods for such characterization. It was finally put forward that an intermediate simple test radar could be implemented to enable sampling system testing and FMCW signal processing of real measurements, if the millimeter partof the radar is further postponed.
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Lundströmer, Torbjörn. "LPI-radar. Nys eller nytta? : Studie av den militära nyttan med LPI-radar". Thesis, Försvarshögskolan, Militärtekniska avdelningen (MTA), 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:fhs:diva-975.
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Sedan radar började användas under första hälften av 1900-talet har duellen mellan radar och signalspaning pågått. Genom att utnyttja radar har alltid en medveten risk tagits, risken att bli upptäckt av motståndarens signalspaning. Duellen gavs möjlighet att ta en paus då radarsystem med låg uteffekt introducerades på marknaden under slutet av 1980-talet, nu fanns plötsligt en möjlighet att använda radar samtidigt som de samtida signalspaningssystemen inte kunde upptäcka dessa radarsystem. I föreliggande magisteruppsats i krigsvetenskap med militärteknisk inriktning undersöks räckviddsförhållanden mellan dessa radarsystem och signalspaningssystem. Genom scenarier i den marina arenan försöker jag värdera de taktiska vinster en användare av radar med låg uteffekt kan göra. Analysen visar på att det fram till dess att signalspaningssystem med förmåga att upptäcka radar som utnyttjar låg uteffekt finns tillgängligt är det möjligt att nå taktiska fördelar med dessa system.Since the advent of radar during the early 20th century the duel between radar and electronic support measurement systems has been practised. Using radar has always been associated with a risk of being detected by an opponent’s electronic support measurement systems. The duel came to a halt when radar systems using low output power were introduced on the market during the late 1980s, now it was possible to use radar without being detected by contemporary electronic support measurement systems. The present master of science (one year) thesis in war science with specialization in military technology looks into the range relationships between radar and electronic support measurement systems. Through scenarios in the naval domain, I seek to assess the tactical benefits a user of low probability of intercept radar may have. The analysis indicates that until electronic support measurement systems with the ability to detect radar systems using low output power are available it is still possible to gain tactical advantages with such systems.
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Uphoff, Jan Luca. "Introduction to automotive FMCW Radar Technologies : Using Texas Instruments mmWave AWR sensor series". Thesis, Blekinge Tekniska Högskola, Institutionen för tillämpad signalbehandling, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-16266.
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The goal of the following thesis is to transfer radar basic theory in a practical work using Texas Instrument’s mmWave radar series. The range of practical applications for FMCW radars has increased, for example in automotive sector. Understanding the basics of radar mathematics in a simplified way, as well as the transfer from theory to practical work is important for any engineer working on radar projects. Even if the theory is known, the way from a theory to a running system can be hard, facing several problems, because the reality is limited. In two experiments, data from the radar is collected while cars are crossing the observation area of the radar.The data is then used to count the number of vehicles passing the observation area and to estimate the movement of the objects in the field of view.
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Halai, S. "Active target location using crossed-dipole based circular array FMCW radar". Thesis, University College London (University of London), 2014. http://discovery.ucl.ac.uk/1458264/.
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Active target location systems capable of measuring both range and bearing have niche applications, including maritime navigation where a seafaring vessel is manoeuvring in the vicinity of a harbour or an oil rig. Such systems can also be used to determine the location of other vessels for vessel-to-vessel personnel or material transfer. The usual approach is to combine FMCW radar with a mechanically or electrically steered beam, establishing both range and bearing to a target, respectively. The radar system described in this thesis is an innovative alternative approach, one that combines FMCW radar with a crossed-dipole antenna, which conveniently functions as a circular array, thereby simultaneously determining the range and bearing of an active target. By using phase mode excitation, neither mechanical nor electrical beam steering is required to locate the active target, as the receive antenna is able to monitor 360 in azimuth continually. However, due to the use of +1st and -1st order phase modes, the radar can only operate in an 180 sector unambiguously. The usual inherent problems with circular arrays being aected by multipath are also easily mitigated by the range resolution of the radar. This thesis describes in detail the development of a 2.44 GHz crossed-dipole antenna structure and its associated feed network. It also describes the first prototypes that led to its current form and goes on to discuss in detail the design and construction of the radar system and frequency shifted active target. Frequency shifting was implemented within the target to overcome the increased clutter power due to the omnidirectional receive antenna. However, firstly this thesis lays the foundation of radar theory, active targets, phase modes and basic antenna theory. Some of the literature associated with radars currently used in this type of scenario is also discussed. Appropriate analysis, modelling and experimental validation is conducted to assess system performance in relation to the predicted behaviour. The radar system was then tested in an open field, with the active target detected to a range of 125 m.
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Crémona, Patrick. "Traitement du signal d'un radar FMCW à visée inclinée pour l'automobile". Toulouse, INPT, 1996. http://www.theses.fr/1996INPT032H.
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La securite routiere reste une des preoccupations majeures de notre societe, et a l'aube du xxi siecle on espere beaucoup de l'electronique embarquee. Ces travaux de recherche montrent qu'avec un radar anticollision, dont la fonction principale est la detection d'obstacles presentant un danger imminent, on peut aussi envisager une caracterisation de la cible route, ce qui renforcerait considerablement la securite automobile. Le but de cette these est donc la mesure de la vitesse absolue du vehicule sur sol et la reconnaissance automatique de l'etat de la route (route seche / route mouillee) pour une meilleure appreciation de la distance de securite a conserver entre deux vehicules. Le manuscrit decrivant cette etude debute par une description des particularites requises pour un radar anticollision automobile, afin de justifier notre choix de developper un radar a ondes continues et a modulation lineaire de frequence (fmcw). Dans la seconde partie, on s'interesse a la cible route pour mieux cerner les mecanismes de reflexions qui interviennent dans le signal radar. On montre que la forme de la densite spectrale de puissance de l'echo radar change avec le type de revetement. La troisieme partie se consacre a la mesure vitesse sur sol du vehicule. On s'est attache a etudier diverses techniques d'analyse spectrale parametrique afin de mettre en evidence les methodes qui assurent une mesure vitesse fiable. Enfin dans la quatrieme et derniere partie, avec l'aide des methodes classiques de classification bayesienne et non bayesienne associees a un pretraitement de compression ou de dilatation spectrale pour compenser l'effet doppler, on reussit a reconnaitre divers revetements de routes
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Kunert, Martin. "Radar FMCW automobile : une approche système globale avec des méthodes modernes". Toulouse, INPT, 1996. http://www.theses.fr/1996INPT120H.
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Pour faire fonctionner un radar fmcw dans l'environnement automobile d'une facon robuste et efficace il faut deux niveaux de traitement de donnees, l'estimation de la frequence du signal et la discrimination et multi-pistage des cibles. Une multiplicite des implantations et les relations mutuelles sont presentees pour ces deux besoins et des nouvelles extensions sont developpees. Importance est mise sur les caracteristiques propres au radar fmcw et les similitudes avec les methodes modernes comme l'analyse avec des ondelettes et des reseaux de neurones. Un filtre de pistage multi-cible incite par des donnees et commande par des regles predefinies et une extraction des pics spectrales basee sur un reseau de neurones sont developpees et appliquees aux signaux enregistres sur la route avec beaucoup de succes et une robustesse accrue
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Gale, Nicholas C. "FUSION OF VIDEO AND MULTI-WAVEFORM FMCW RADAR FOR TRAFFIC SURVEILLANCE". Wright State University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=wright1315857639.
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Mackie, James David. "Compact FMCW Radar for GPS-Denied Navigation and Sense and Avoid". BYU ScholarsArchive, 2014. https://scholarsarchive.byu.edu/etd/4388.
Texto completoResumen
Location information is vital for any type of aircraft and even more crucial for Unmanned Aerial Systems (UAS). GPS is a readily available solution but signals can easily be jammed or lost. In this thesis, radar is explored as a backup system for self-localization when GPS signals are not available. The method proposed requires that an area be pre mapped by collecting radar data with known latitude and longitude coordinates. New radar data is then collected and compared to previously stored values. Channel matrices are stored at each point and are used as the basis for location comparisons. Various methods of matrix comparison are used and both simulation as well as experimental results are shown. The main results of this thesis show that position can be determined using channel matrices if the sensor is within a certain radius of previously stored locations. This radius is on the order of a wavelength or less. Using correlation matrix comparisons the radius of localization is broadened. A novel method using multiple channel and multiple frequency data proves to be successful and determines the position of an octorotor UAS with a mean position error of less than three meters. The design of a low-cost, compact, and light-weight FMCW radar for two applications is also presented. The first application is a novel radar based positioning system that utilizes multiple channel and multiple frequency information to determine position. The second application is a UAS sense and avoid system using a monopulse configuration. Without connectors or antennas, the radar weighs 45.7 grams, is 7.5 cm x 5 cm x 3 cm in size, and costs less than $100 when built in quantities of 100 or more (excludes antennas and connectors). It is tested using delay lines and corner reflectors and accurately determines the distance to close range targets.
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Toverland, Anders. "Icke modellbaserad ekoföljning för radarnivåmätning". Thesis, Linköping University, Department of Electrical Engineering, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-5960.
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Denna rapport behandlar en fullständig metod för att följa, associera och klassificera ekospår. Vid radarnivåmätning ska ekon som härstammar ifrån samma fysikaliska objekt följas över tiden och klassificeras. Dagens radarnivågivare löser problemet genom konfiguration. Tankens geometri samt vilka störande objekt som finns anges vid installation.
Den framtagna metoden har delats upp i tre delmoment. Först binds individuella inmätta ekon samman till linjesegment. Dessa segment associeras samman till ekospår varefter dessa klassas fysikaliskt. Metoden kräver betydligt mindre konfiguration än den lösning som används för tillfället.
In this report a method for target tracking, association and classification of echo tracks in radar level gauges is discussed. In tank gauging echoes from the same physical object are called an echo track. The echoes must be tracked over time and classified. Currently radar level gauge units requires configuration to achieve classifications of echo
tracks. At installation tank geometry and disturbing echoes has to be registered.
The method has been divided into three parts. Firstly individual measured echoes are replaced by line segments. Association algorithms then create echo tracks from these segments. The third step is to classify these tracks physically. This method eliminates registering of disturbing echoes.
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Svensson, Jonny. "Implementation of an FMCW Radar Platform With High-Speed Real-Time Interface". Thesis, Linköping University, Department of Electrical Engineering, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-6163.
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Acreo AB has developed a radar prototype used for illustrate how the SiGe technology could be used. The radar prototype needs further development with a fast interface and a more integrated design. The beginning of the report describes the radar technique theory and the composing equations. The theoretical background is used to explain each component of the system. The report continues by specifying the target of the next radar prototype. The chosen implementation is motivated and the mode of procedure is described in detail. Test benches were used to verify correct functionality and some limits were found. The report is concluded with test results and recommendations on further enhancements.
Acreo AB har utvecklat en radarprototyp för att illustrera hur SiGe teknologi kan användas. Prototypen behöver vidareutvecklas med ett snabbt digitalt interface och en kompaktare design. Rapporten inleds med att beskriva radarteknikens funktionalitet och de utgörande ekvationerna. Den teoretiska bakgrunden används för att förklara varje komponent som systemet utgörs av. Rapporten fortsätter med att specificera målet med nästa radarprototyp. Den valda implementationen motiveras och tillvägagångssättet beskrivs detaljerat. Testuppkopplingar verifierade korrekt funktionalitet och begränsningar insågs. Rapporten avslutas med en sammanfattning av uppnådda testresultat och rekommendationer på framtida förbättringar.
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Undheim, Ruben. "Design of a Linear FMCW Radar Synthesizer with Focus on Phase Noise". Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for elektronikk og telekommunikasjon, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-16787.
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The linear FMCW radar has become more popular in recent years mainly due toadvances in digital signal processing and the good performance of the radar at closeranges. What puts limits to the performance is mainly phase noise. Because trans-mission and reception happen simultaneously, the phase noise will limit the maxi-mum power that should be used and hence also the ability to detect weak targets.By ensuring during the design process that the phase noise is low, the radar’s perfor-mance will thus get better. This thesis describes the construction of a FMCW radarfrequency synthesizer where the focus is mainly on phase noise. The functionalityof the circuit is shown to be successful, but there is more phase noise than what ispredicted. Several causes for this are discussed. Important background theory aboutradars, phase noise and phase-locked loops is presented and several simulations areperformed in order to get a better understanding. The conclusion of the work isthat it is not very hard to build a synthesizer, but in order to tweak the phase noiseperformance to be as good as the linear theory tells it to be, careful attention mustbe paid during all stages of the design.
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Goy, Philippe. "Détection d'obstacles et de cibles de collision par un radar FMCW aéroporté". Thesis, Toulouse, INPT, 2012. http://www.theses.fr/2012INPT0156/document.
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Cette thèse, réalisée en partenariat avec Rockwell-Collins France, s'inscrit dans le cadre du développement d'un radar FMCW aéroporté de détection d'obstacles fonctionnant en bande X. Dans cette thèse, nous nous plaçons dans le contexte plus général de détection de cibles présentant un risque de collision avec le porteur radar dans du fouillis de sol. Les performances de détection des cibles d'intérêt diminuent grandement lorsqu'elles se retrouvent dans les zones de fouillis. Le principal objectif de cette thèse réside ainsi dans la conception de traitements en vue d'améliorer les capacités de détection et de reconnaissance de cibles présentant un risque de collision avec le porteur radar dans les zones de fouillis de sol. Dans un premier temps, nous effectuons une revue des traitements adaptés à la détection d'obstacles par un radar aéroporté FMCW: formation de faisceaux conventionnelle, compensation de migration distance, et création d'une cartographie distance-vitesse par double FFT. Dans un second temps, nous utilisons ensuite un traitement d'antennes adaptatif pour séparer en élévation le fouillis de sol et d'éventuels obstacles situés au-dessus du sol pouvant présenter un risque pour le porteur (câbles, pylônes, immeubles, ...). Dans la seconde partie de cette thèse, nous incluons une information supplémentaire sur le signal temporel d'une case distance avec un temps d'intégration plus long~: la variation de fréquence Doppler des cibles. Une cible de collision ou un câble ne changent pas de fréquence tandis qu'un élément au sol aura une variation connue dépendant de la vitesse du porteur et de son angle de vue. Cette information nous a tout d'abord permis de séparer le signal d'un pylône et d'un câble, pour ensuite séparer la cible de collision du fouillis de sol. Enfin, nous effectuons la détection adaptative d'une cible mobile de collision étendue en distance et noyée dans le fouillis de sol. Les algorithmes développés dans cette thèse ont été testés avec succès sur données expérimentalesThis thesis, in collaboration with Rockwell-Collins France, forms part of the development of an X-band FMCW airborne radar designed for obstacles detection and collision avoidance. More precisely, this thesis deals with the problem of detecting targets which exhibit a collision trajectory with the radar carrier, in presence of ground clutter. Target detection performances are highly degraded when the targets of interest fall into ground clutter. The main goal of this thesis is to develop signal processing methods to increase radar detection capacities and recognition for collision targets inside ground clutter. First, we give a brief review of signal processing methods for target detection using an airborne FMCW radar : conventional beamforming, range migration compensation, double-FFTs for Range-Doppler Map visualization. We then derive an adaptive antenna array processing to separate ground clutter and fixed hazardous obstacles above the ground (cables, pylons, buildings, ...) using their difference in elevation angle. In the second part of this thesis, we use a long integration time and include extra information on the time model of a range cell signal : Doppler frequency variation. A collision target does not exhibit Doppler frequency variation, whereas fixed obstacle or ground clutter exhibits a known variation depending on the carrier velocity and the aspect angle. We take advantage of this variation first to separate a cable from a pylon, and then separate collision target from ground clutter. We finally tackle the problem of adaptively detecting a collision mobile spread target in ground clutter region. The proposed algorithms in this thesis have been successively tested on experimental data
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El, Agroudy Naglaa, Mohammed El-Shennawy, Niko Joram y Frank Ellinger. "Design of a 24 GHz FMCW radar system based on sub-harmonic generation". The Institution of Engineering and Technology (IET), 2018. https://tud.qucosa.de/id/qucosa%3A33989.
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This study presents a novel frequency modulated continuous wave (FMCW) radar system based on sub-harmonic generation, where a 24 GHz frequency divider-by-10 is used as an active reflector tag. A practical prototype is designed and fabricated on a GF45nm-Silicon on Insulator (SOI) technology for the 24 GHz building blocks, while a GF0.18 μm 7WL Bipolar Complementary Metal Oxide Semiconductor (BiCMOS) technology was used for the 2.4 GHz receiver and baseband. System measurement results show that as opposed to conventional primary radars, the proposed system is immune to strong multi-path interferences resulting from direct reflections of the interrogating signal. The system achieves a ranging precision of 3.7 mm with loop measurements. Moreover, when measured in an indoor environment, the ranging results show a ranging precision and accuracy of 5.8 and 22.3 cm, respectively, which outperform other FMCW radars in the literature.
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Ghetti, Gabriele. "Studio Sperimentale delle Prestazioni di un Radar FMCW per Applicazioni Indoor e Outdoor". Master's thesis, Alma Mater Studiorum - Università di Bologna, 2020.
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La crescente domanda relativa ai sistemi di localizzazione e tracking a partire dal settore automotive fino a quello della difesa, ha aperto la strada verso una rivoluzione nelle tecnologie di detection e ranging. Tra i vari dispositivi sviluppati in tale ambito vi sono i sistemi radar, i quali possiedono alcuni vantaggi che li contraddistinguono da tutti gli altri tipi di sensori. Grazie al loro principio di funzionamento infatti, possono operare in qualsiasi condizione di luce, tempo atmosferico ed in ambienti con scarsa sicurezza operativa. Queste caratteristiche collocano i sistemi radar al centro di numerosi studi, laddove vi sia l’obbiettivo di implementare tecnologie di localizzazione accurate e sempre più economiche. Sono state proposte nel corso del tempo diverse categorie di sistemi radar, ognuna con i suoi pregi e difetti; nello specifico in questo elaborato si concentra l’attenzione sui sistemi radar FMCW, i quali utilizzano una particolare modulazione in frequenza del segnale. Nonostante tale tecnologia sia stata studiata ed implementata decine di anni fa, il radar FMCW ` e tutt’ora oggetto di studio, dal momento che in passato lo sviluppo delle tecnologie digitali non permetteva la rapida esecuzione di algoritmi con una determinata complessità computazionale. Si ricordano inoltre i notevoli progressi nel design di circuiti a radiofrequenza che hanno portato alla costruzione di radar ad onde millimetriche, che posso offrire un’accuratezza notevole rispetto ad altri tipi di radar. In questo lavoro di tesi si illustra innanzitutto una visione di principio dei sistemi radar FMCW. Successivamente viene descritta una teoria generale per l’analisi del segnale utilizzato dal radar. Infine si illustrano le campagne di misura e l'elaborazione dei dati.
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Liau, Teh-Fu. "Digital signal processing for the detection of hidden objects using an FMCW radar". Thesis, Queen Mary, University of London, 1987. http://qmro.qmul.ac.uk/xmlui/handle/123456789/1591.
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This thesis deals with the detection of hidden objects using a short-range frequency-modulated continuous wave (FMCW) radar. The detection is carried out by examining the estimated Power Spectral Density (PSD) functions of sampled returns, the peaks of which theoretically correspond to the reflecting surfaces of hidden objects. Fourier and non-Fourier PSD estimation algorithms are applied to the radar returns to extract information on the hidden surfaces. The Fourier methods used are Direct, Blackman-Tukey, Bartlett, and Smoothed Periodograms. The different PSDs are compared, and the validity of each PSD is then discussed. The study is new for this type of radar and the results are used as references for other PSD estimations. Non-Fourier methods offer many advantages. Firstly the Autoregressive Process (AR) is used for this particular application. As well as PSDs the noise spectra are also produced to show the performance of the chosen models. An alternative approach to the conventional forward-backward residuals ( e. g. Burg's method) or autocorrelation and covariance methods ( as those used in speech analysis ) is introduced in this thesis. The stability and good resolution of the PSDs is obtained by a better estimation of the autocovariance coefficients (ACF) from the data available : averaging two p-shifted ACF calculated by covariance method. Once the covariance coefficients are found, the Levinson-Durbin recursive algorithm is used to get the model parameters and the PSDs. Two other non-conventional methods are also attempted to show the image of hidden objects. They are Pisarenko Harmonic Decomposition method and Prony energy spectrum density estimation. In addition to the one-dimensional processing stated above, this thesis extends it to two-dimensional cases, which give more information on the shape of hidden objects.
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Thayyil, Manu Viswambharan, Songhui Li, Niko Joram y Frank Ellinger. "A K-band SiGe Super-Regenerative Amplifier for FMCW Radar Active Reflector Applications". Institute of Electrical and Electronics Engineers, Inc. (IEEE), 2018. https://tud.qucosa.de/id/qucosa%3A35127.
Texto completoResumen
A K-band integrated super-regenerative amplifier (SRA) in a 130nm SiGe BiCMOS technology is designed and characterized. The circuit is based on a novel stacked transistor differential cross-coupled oscillator topology, with a controllable tail current for quenching the oscillations. The fabricated integrated circuit (IC) occupies an area of 0.63mm2, and operates at the free-running center frequency of 25.3 GHz. Characterization results show circuit operation from a minimum input power
level required for a phase coherent output as −110 dBm, and the input power level corresponding to the linear to logarithmic mode transition of −85 dBm, the lowest reported for K-band integrated logarithmic mode SRAs to date to the knowledge
of the authors. The measured output power is 7.8dBm into a 100 differential load. The power consumption of the circuit is 110mW with no quench signal applied, and 38mW with 30 % duty cycle quenching. The quench waveform designed for the
reported measurement result is also discussed.
37
Trange, Axel. "FMCW mmWave Radar for Detection of Pulse, Breathing and Fall within Home Care". Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-292411.
Texto completoResumen
Countless of elderly people fall and get hurt within their homes, worldwide, every year, and as they can not always reach out for help themselves, they end up helplessly waiting for someone to notice what has occurred. Throughout this work, it is investigated if remote sensing of the mmWave FMCW radar IWR6843AOPEVM can be adopted to detect the incident of falls, and also detect the vital signs of the human subject. The goal is to prove that this is possible in a home care environment. By locating the sub-range resolution oscillatory motions, caused by breathing and heartbeats, and unwrapping consecutive phase measurements of multiple range bins and multiple virtual antennas, human heart rate for seated position is estimated with a RMS-Error of 3.49 beats/min (at 1.0 m range with 120_ FoV) for a 130 second time sequence. Analogously, breathing rate is estimated for a sitting person with a RMS-Error of 0.29 breaths/min (at 4.0 m range with 120_ FoV) for a 100 second time sequence. Different estimation methods are evaluated, such as Fourier transform (FFT), Chirp Z-transform (CZT) and autocorrelation peak-finding, where the CZT approach is deemed to provide the best estimations. Methods are presented to minimize spectral leakage, improve spectral resolution and reduce breathing harmonics. The measurements were performed in a home care environment and the heart rate ones were compared to measurements of the FDA approved pulse oximeter CMS50D+. 729 own recordings of range-doppler-time data was collected for the fall detection, which was fed into a convolutional neural network to extract image features. These features were then used as training and softmax classified by a LSTM recurrent neural network for multi-label classification. Promising results on separate test data showed a balanced accuracy for fall detection as 92% with a direct 2% false positive rate and 15% false negative rate. The area under the ROC curve for the falls was close to 1, namely 0.99, illustrating that the false negative rate may be chosen as lower at the cost of slightly more false alarms. A sweet spot in the ROC curve suggested that fall detection was possible with a 3.5% false positive rate and 6% false negative rate.Många äldre människor faller och skadas inom sina hem, världen över, varje år, och eftersom de inte alltid kan hämta hjälp själva, får de hjälplöst vänta på att någon ska upptäcka vad som har skett. I detta arbete undersöks det om mmWaveFMCW-radarn IWR6843AOPEVM kan användas för att upptäcka fall inom hemmet, samt även puls och andning, med syfte att kunna larma om någonting går snett. Målet är att visa att detektion är möjligt i en hemvårdsmiljö. Genom att lokalisera ett föremål som oscillerar med avstånd mindre än radarns avståndsupplösning, och kombinera på varandra följande fasmätningar inom flera avstånd, lyckades puls bestämmas för en sittande människa med en RMSE av 3.49 slag/min (på 1.0 m avstånd med 120_ FoV) för en sekvens av 130 sekunder. På liknande sätt bestämdes andningsfrekvensen av en sittande person till en noggrannhet motsvarande RMSE av 0.29 andetag/min (på 4.0 m avstånd med 120_ FoV) för en sekvens av 100 sekunder. Olika uppskattningsmetoder av frekvenserna utvärderas, så som Fourier transform (FFT), Chirp Z-transform (CZT) och en autokorrelations-metod, där CZT-metoden bedöms ge bäst resultat. Metoder presenteras för att minska störningar i frekvensdomän, förbättra upplösningen i frekvensdomän och för att reducera övertoner från andnings-signalen. Mätningarna utfördes i en hemvårdsmiljö och uppskattningarna för hjärtfrekvens jämfördes med den mätta frekvensen av den FDA-godkända pulsoximetern CMS50D+. 729 egna inspelningar av avstånd-doppler-tid-data samlades in för falldetekteringen, som matades in i ett neuralt faltnings-nätverk för att extrahera egenskaper från bilder. Dessa egenskaper användes sedan som träning med softmax klassificering i ett återkopplat neuralt nätverk med LSTM celler för klassificering av flertal gester. Lovande resultat på skild testdata fick den viktade noggrannheten för falldetektering till 92% med 2% falska positiva och 15% falska negativa förutsägelser. Arean under ROC-kurvan för fallen var nära 1, nämligen 0.99, vilken visar att mängden falska negativa förutsägelser kan minskas på bekostnad av att acceptera fler falsklarm. Förslagsvis kunde en implementering uppfylla 3.5% falsklarm och 6% missade fall.
38
Prakash, Jay. "Simulation of FMCW mode MIMO Radar for Performance Analysis as Industrial Safety System". Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-300711.
Texto completoResumen
In industrial environments workers can be prone to dangerous situations that may cause harm. In order to prevent accidents and fulfill legislative requirements for safe working condition, a safety system can be needed to be installed in place. In an attempt to bring a principal improvement in the safety standards offered by conventional systems in existence, a radar sensor is proposed for the detection of dangerous situations. This thesis explores the limiting performance of the radar sensor in an industrial safety system. The radar sensor is an FMCW mode MIMO radar and we develop a model to simulate the radar sensor based on its hardware design. The model is utilized to deduce and analyze the performance limits of the radar sensor, by using a Finite Element Method to determine the electromagnetic scattering response of a target in the operating frequency band, 60-64 GHz. Appropriate dielectric and magnetic properties of human tissue is assigned to obtain accurate scattering responses of a human body target. The performance analysis is done by comparing the reflection from various protruding body parts, with the reflection from the torso, over a wide range of postures of the body. Further, CFAR, a common form of detection algorithm is applied on a few of the postures to detect a protruding part the body. Finally, a discussion on the limited performance is made, and potential methods to enhance the performance of the radar sensor in an industrial safety system are suggested.I industriella miljöer kan arbetare utsättas för farliga situationer vilka kan orsaka skador. För att förhindra olyckor och uppfylla lagstadgade krav för säkra arbetsförhållanden kan säkerhetssystem behöva installeras på plats. I ett försök att åstadkomma en förbättring av de säkerhetsstandarder som erbjuds av konventionella system föreslås en radarsensor för att detektera farliga situationer. Denna avhandling undersöker möjliga begränsningar i prestanda hos en radarsensor, vilken ingår som komponent i ett industriellt säkerhetssystem. Radarsensorn är en MIMO-radar, som arbetar i FMCW-mod, och vi utvecklar en modell för att simulera radarsensorn utgående ifrån dess hårdvarudesign. Modellen används för att härleda och analysera begränsningar i prestanda hos radarsensorn, genom att med hjälp av finita elementmetoden beräkna spridningen av elektromagnetiska vågor från ett radarmål i frekvensbandet 60-64 GHz. Tillämpliga dielektriska och magnetiska egenskaper hos mänsklig vävnad har använts för att erhålla tillförlitliga data på spridningsresponsen för människokroppen. Prestandaanalysen görs genom att jämföra reflektionen från olika utskjutande kroppsdelar med reflektionen från bålen över ett stort antal kroppshållningar. Vidare, CFAR, en vanlig form av detektionsalgoritm tillämpas på några av hållningarna för att detektera utskjutande delar av kroppen. Avslutningsvis diskuteras begränsningarna i prestandan och potentiella metoder för att förbättra radarsensorns prestanda i ett industriellt säkerhetssystem föreslås.
39
Farneti, Elia. "Millimeter wave radar for SLAM applications". Master's thesis, Alma Mater Studiorum - Università di Bologna, 2020. http://amslaurea.unibo.it/19782/.
Texto completoResumen
Lo scopo di questa tesi è quello di introdurre la tecnologia radar ad onde millimetriche applicata a problemi di mapping e di localizzazione in modo da investigare la fattibilità del recente concetto di "personal radar".
Più specificatamente, può essere inteso come una caratteristica futura degli apparecchi mobili per la stima delle mappe degli ambienti interni sfruttando le tecnologie di comunicazione già presenti, avendo così la possibilità di creare applicazioni di localizzazione che non necessitano di infrastrutture ad-hoc.
Il personal radar scansiona automaticamente l'ambiente circostante e mediante l'utilizzo di antenne colleziona le risposte provenienti dall'ambiente ad ogni direzione di scansione. Successivamente analizzando i dati collezionati il personal radar è in grado di dedurre la mappa dell'ambiente. Al momento le tecnologie più usate sono quella lidar o quella camera-based ma sono solitamente tecnologie più costose e che richiedono supporti meccanici e perfette condizioni di visibilità dell'ambiente. Per queste ragioni è interessante esplorare la tecnologia radar ad onde millimetriche. Questa teconologia infatti offre la possiilità di impacchettare un numero elevato di antenne in un piccolo spazio e quindi di realizzare diagrammi di radiazione molto stretti alle spese di una degradazione delle perfomance.
Per queste ragioni è stato deciso di suddividere la tesi nei seguenti capitoli.
Nel primo capitolo viene fornita una breve spiegazione della teoria radar con attenzione particolare alla tecnologia (FMCW) del dispositivo utilizzato. Nel secondo capitolo viene fornita una analisi della teoria dello SLAM con un approfondimento sulla teoria SLAM basata su grafi. Dopodichè è presente una analisi del dispositivo utilizzato. Nel quarto capitolo vengono descritti gli algoritmi sviluppati e i motivi per cui sono stati necessari e infine nel capitolo finale vengono riportati i risultati finali con le relative considerazioni.
40
CIATTAGLIA, Gianluca. "Modern techniques to process micro-Doppler signals from mmWave Radars". Doctoral thesis, Università Politecnica delle Marche, 2022. http://hdl.handle.net/11566/295142.
Texto completoResumen
I sistemi radar mmWave stanno diventando molto comuni sui veicoli e le loro capacità, in termini di portata e velocità, li rendono adatti a un'altra classica applicazione radar classica, quella relativa all'effetto micro-Doppler. Dall'elaborazione dei segnali radar mmWave, l'effetto micro-Doppler può essere sfruttato, rendendo così possibile estrarre informazioni interessanti sui bersagli. Con l'enorme larghezza di banda e il breve tempo di trasmissione del segnale, l effetto micro-Doppler può essere utilizzato per diversi scopi come la vibrazione del bersaglio o la classificazione dei bersagli. Grazie anche al progresso delle tecniche di Machine Learning, la loro combinazione con elaborazione del segnale radar è un campo interessante da esplorare e può essere usato per fornire soluzioni a diversi problemi radar. L'effetto Micro-Doppler ha una lunga storia nei sistemi radar, un sacco di letteratura può essere trovata su questo argomento, ma la maggior parte di loro considera dispositivi non commerciali quindi è abbastanza lontano da un caso pratico. In questa dissertazione, diverse tecniche per elaborare i segnali micro-Doppler provenienti da radar automobilistici sarà presentato, con lo scopo di classificarli ed estrarre informazioni sulle vibrazioni dal bersaglio. Il contributo principale di questo lavoro è la proposta di nuove tecniche che possono essere applicato su un sensore commerciale e li rende adatti per il micro- Doppler.mmWave Radar systems are becoming very common on vehicles and their capabilities, in terms of range and velocity, make them suitable for another classical radar application, the one related to the micro-Doppler effect. From the processing of mmWave radar signals, the micro-Doppler effect can be exploited, making so possible to extract interesting information on the observed targets. With the huge bandwidth and the short signal transmission time, the micro-Doppler effect can be used for different purposes such as target vibration measurements or targets classification. Thanks also to the advance of Machine Learning techniques, their combination with radar signal processing is an interesting field to explore and can be used to provide solutions to different radar problems. The Micro-Doppler effect has a long story in Radar systems, a lot of literature can be found on this topic but most of them consider non-commercial devices so is quite away from a practical case. In this dissertation, different techniques to process the micro-Doppler signals coming from automotive radars will be presented, with the purpose of classifying them and extracting vibration information from the target. The main contribution of this work is the proposal of novel techniques that can be applied on a commercial sensor and makes them suitable for the micro- Doppler application.
41
Thornton, Matthew. "Frequency Partition Techniques of FMCW Radar Imaging Systems for MIMO Multi-Static Array Modality". International Foundation for Telemetering, 2016. http://hdl.handle.net/10150/624193.
Texto completoResumen
The modalities of many imaging applications have been advancing toward the MIMO format for
improved efficiency. This paper presents an approach to the implementation of the MIMO
operating modality for FMCW radar imaging systems with multi-element data-acquisition
arrays. The unique characteristics of the software-defined step-frequency FMCW imaging
systems enable the simple and precise orthogonalization procedure through direct spectral
partitioning. This paper includes the description of the data-acquisition hardware of an eighttransceiver
radar imaging system, imaging formation algorithms, MIMO implementation, and
results of laboratory experiments.
42
Decourt, Colin. "Extraction et identification de cibles multiples pour radar automobile à l'aide d'intelligence artificielle". Electronic Thesis or Diss., Toulouse 3, 2023. http://www.theses.fr/2023TOU30321.
Texto completoResumen
Ces dernières années, l'apparition de véhicules de plus en plus connectés ont ouvert la voie à des modes de transports plus sûrs et plus autonomes. Ces véhicules s'appuient sur des systèmes avancés d'aide à la conduite (ADAS) et utilisent divers capteurs comme le radar, la caméra, le LiDAR et le V2X pour créer un cocon de sécurité à 360° autour du véhicule. Si l'intelligence artificielle et l'apprentissage profond ont permis la détection et l'identification d'objets en temps réel à l'aide de caméras et de LiDAR, l'utilisation de ces algorithmes sur des données radar est encore limitée. Pourtant, les radars présentent des avantages, notamment celui de fonctionner dans des conditions météorologiques difficiles et d'offrir de bonnes performances en terme de résolution en distance, angulaire et en vitesse, à un coût inférieur à celui du LiDAR. Cependant, les données renvoyées par les radars actuels contiennent peu d'information concernant les cibles détectées et plusieurs étapes de pré-traitement et de post-traitement sont nécessaires pour les obtenir. Ces étapes de traitement dénaturent le signal brut réfléchi par les objets, pouvant affecter les performances des algorithmes d'intelligence artificielle. Ce doctorat vise à développer de nouveaux algorithmes d'apprentissage profond spécifiquement adaptés aux données radar, visant à être incorporés dans des systèmes automobiles. Ces algorithmes auront pour but de détecter et identifier les objets autour d'un véhicule dans des environnements complexes. Outre les algorithmes, cette thèse étudiera quelles types de données radar, et donc quelle quantité de pré-traitement, permettent d'obtenir les meilleures performances. Les algorithmes proposés dans cette thèse devront satisfaire aux contraintes des environnements automobiles: faible puissance, faible complexité et temps de réaction rapideIn recent years, connected vehicles have paved the way for safer and more automated transportation systems. These vehicles rely heavily on Advanced Driving Assistance Systems (ADAS) and use various sensors like radar, camera, LiDAR, and V2X to ensure 360° safety type of cocoon around the vehicle. While artificial intelligence and deep learning have enabled real-time object detection and identification using cameras and LiDAR, the use of such algorithms on radar data is still limited. Radar sensors offer advantages, such as working in challenging weather conditions and providing good performance in distance, angular and speed resolution, at a lower cost than LiDAR. However, radars output relatively low content information regarding the detected targets and several pre and post-processing steps are required to obtain those. Since the processing steps filter the raw signal returned by objects, it can affect the performance of AI algorithms. This PhD aims to develop new deep learning algorithms explicitly tailored for raw radar data to integrate them into automotive systems. These algorithms will detect and identify objects in complex environments. Additionally, this thesis will explore the optimal types of radar data and pre-processing steps for achieving the best performance. The algorithms will have to meet automotive constraints, including low power consumption, simplicity, and fast response times
43
Thayyil, Manu Viswambharan, Hatem Ghaleb, Niko Joram y Frank Ellinger. "A 28 GHz Superregenerative Amplifier for FMCW Radar Reflector Applications in 45 nm SOI CMOS". Institute of Electrical and Electronics Engineers (IEEE), 2018. https://tud.qucosa.de/id/qucosa%3A35128.
Texto completoResumen
This paper presents the design and characterization of a 28GHz integrated super-regenerative amplifier (SRA) in a 45 nm silicon on insulator (SOI) technology. The circuit is based on a complementary cross-coupled oscillator topology. The fabricated integrated circuit (IC) occupies an area of 0.67 mm 2 , and operates in a frequency range from 28.07GHz to 29.35 GHz. Characterization results show the minimum input sensitivity of the circuit, as -85 dBm and the input power level corresponding to the linear to logarithmic mode transition as -66.3 dBm. The measured output power delivered into a 100 Ω differential load is 1.1 dBm. The DC power consumption of the circuit is 10.6 mW. To the knowledge of the authors, the circuit has the best reported combined sensitivity and output power for an FMCW radar reflector implementation in CMOS.
44
Guedaiem, Sami. "Detection et suivi de cibles par radar automobile a onde continue modulee en frequence (fmcw)". Toulouse 3, 1997. http://www.theses.fr/1997TOU30203.
Texto completoResumen
Afin d'assurer une securite maximale dans les vehicules, les constructeurs automobiles consacrent, aujourd'hui, une recherche considerable pour le developpement de nouveaux systemes embarques utilisant la technologie radar. Ces systemes ont principalement pour objet d'eviter toute collision autant que faire se peut. Les radars a onde continue modulee en frequence (fmcw) sont ceux qui semblent le mieux convenir pour cette application. Notre travail de recherche se situe dans ce cadre. Il concerne precisement le developpement d'un traitement adequat du signal radar permettant de detecter la presence des vehicules et des obstacles situees devant le vehicule equipe, de determiner leur distance et leur vitesse et de suivre leur evolution dans le temps. Nous specifions, dans un premier temps, les caracteristiques du radar fmcw et nous precisons la modulation de frequence que nous envisageons pour assurer la detection des cibles. Nous examinons, en outre, les phenomenes physiques qui affectent le traitement du signal radar. Le probleme de detection est ensuite etudie. On y traite la determination des distances et des vitesses des cibles detectees. Ce probleme se ramene a un probleme d'analyse spectrale consistant a estimer les frequences et le nombre de sinusoides dans le signal radar. Nous appliquons ainsi la methode parametrique arma, suivie d'une technique appropriee d'estimation du nombre d'harmoniques. Les performances de cette procedure sont examinees a partir d'une etude detaillee de simulations. Une technique combinatoire est appliquee pour en deduire les distances et les vitesses des cibles a partir des frequences. Enfin, nous nous interessons au probleme de poursuite des cibles dans un environnement degrade. Nous decrivons une procedure de suivi multicible monosenseur fondee sur le filtrage de kalman et utilisant le filtre a hypotheses multiples (mhf) de d. B. Reid. Nous prouvons la robustesse et l'efficacite de cette procedure par une etude de simulations.
45
Middleton, Robert. "Techniques for homodyne dechirp-on-receive linearly frequency modulated radar". Thesis, University of St Andrews, 2011. http://hdl.handle.net/10023/1843.
Texto completoResumen
This thesis presents work done to extend and improve the operation of homodyne dechirp-on-receive linearly frequency modulated radars. First, an investigation of the effect of common phase errors on the point response function of the radar is described. The dependence on the window function of the degradation due to phase errors is investigated, and a simple, precise, and general approach for calculating the degraded Point Spread Function (PSF) is described and demonstrated. This method is shown to be particularly useful when investigating the effect of chirp nonlinearity on the PSF. Next, a method for focussing range profiles that are degraded by chirp nonlinearity is described. This method is based on two established methods, the Phase Gradient Algorithm (PGA) and a time-domain re-sampling technique. The technique is entirely hardware independent, allowing any homodyne dechirp-on-receive linearly frequency modulated radar to be focussed. Where suitable archive signal data exists, focussed imagery can even be produced from radars that no longer exist. The complete algorithm and details of the implementation are described, and the technique is demonstrated on three representative radar cases: extreme chirp nonlinearity, typical chirp nonlinearity, and a retrospective case. In all of the cases, it was shown that the PSF was dramatically improved. A technique based on down conversion by aliasing for reducing the required sampling rate is described, and a simple technique for calculating suitable sampling rates is presented. This method is demonstrated for a typical application in which sampling rate reduction might be required, namely Moving Target Indication (MTI). The MTI application is described and quantified, including a simple technique for choosing suitable radar operation parameters. The MTI technique with subsampling was demonstrated in software simulations and in a simple radar experiment. A Synthetic Aperture Radar (SAR) test bench for researching component performance and scatterer properties in the context of SAR was developed. An appropriate image formation processing algorithm was found and modified to better suit the task of a short data collection baseline and drifting centre frequencies, both of which are present in the test bench situation. Software was written to collect data, to control the hardware, and to process the signals into SAR images. A data simulator was written to test the image formation algorithm implementation; it also served as a useful tool for investigating the effect of signal errors on the quality of the resultant SAR imagery. A suitable oscillator was chosen for the task, based on phase noise and centre frequency stability considerations, both of which are quantified and discussed. Preliminary SAR imagery was produced, indicating that the system operates correctly and in agreement with comparable systems.
46
Chebila, Franck. "Lecteur radar pour capteurs passifs à transduction radio fréquence". Phd thesis, Institut National Polytechnique de Toulouse - INPT, 2011. http://tel.archives-ouvertes.fr/tel-00595578.
Texto completoResumen
Un nouvel axe de recherche sur les réseaux de capteurs a été initié au LAAS par la réalisation de nouveaux capteurs sans fil passifs utilisant une transduction électromagnétique dans la détection de pression et de gaz. Ces capteurs fortement intégrés ne nécessitent aucune alimentation embarquée et leur fréquence de fonctionnement se situe dans la bande de fréquence Ka (26 à 40 GHz). Cette thèse s'inscrit donc dans la conception et la réalisation d'un lecteur adapté à l'interrogation à distance de capteurs à transduction électromagnétique. Son principe de fonctionnement est basé sur une technologie radar de type FMCW. L'avantage principal de la lecture radar des données issues de ce type de capteurs passifs réside dans la possibilité d'avoir des portées de plusieurs dizaines de mètres, bien supérieures à celles classiquement obtenues dans les technologies SAW ou RFID. Dans une première étape est présenté le principe de fonctionnement du lecteur radar et la réalisation de deux prototypes centrés sur les fréquences de 3GHz et 30GHz. Une étude du spectre de la sortie radar, appelé signal de battement radar, est abordée afin de montrer comment les positions et les mesures des capteurs sont lues à distance par ce type de lecteur. Par la suite, un travail d'analyse de la communication sans fil permet de déterminer les paramètres de rétrodiffusion électromagnétique à prendre en compte, tels que les impédances et les fréquences de fonctionnement des capteurs. Ces paramètres sont la base d'une optimisation du système global en termes de sensibilité, de portée radar et des niveaux minimaux de Surface Equivalente Radar (SER) des cibles interrogées. La validation de cette analyse se borne à la mesure de la portée maximale associée à ce type de lecteur et aux différentes mesures de SER de plusieurs types de capteurs dans les bandes de fréquence de 3GHz et 30GHz. Deux principes d'identification de cellules passives sont ensuite présentés. Le premier est basé s ur l'utilisation des deux modes de rétrodiffusion de la SER d'un capteur (mode de structure et mode d'antenne) favorisant dans le même temps l'identification sur un mode et la mesure de la grandeur physique sur l'autre, a distance du lecteur. Le deuxième principe utilise le spectre d'un diffuseur multi-bande dont sa SER reconfigurable permet d'associer l'identification de chaque capteur dans un réseau, à la manière d'un code barre. En conclusion, les résultats obtenus dans cette étude valident le principe d'interrogation à longue distance de réseau de capteurs passifs et ouvrent de nouvelles perspectives sur la conception de nouvelles cellules de mesures pour de nouvelles applications dans les secteurs de l'aéronautique, du nucléaire, et de l'environnement.
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Spencer, Jonathan Cullinan. "A Compact Phased Array Radar for UAS Sense and Avoid". BYU ScholarsArchive, 2015. https://scholarsarchive.byu.edu/etd/5837.
Texto completoResumen
As small unmanned aerial systems (UAS) are introduced into the national airspace, measures must be introduced to ensure that they do not interfere with manned aviation and other UAS. Radar provides an attractive solution because of its inherent range accuracy and because it works in diverse weather and lighting conditions. Traditional radar systems, however, are large and high power and do not meet the size, weight and power (SWaP) constraints imposed by UAS, and fully integrated automotive solution do not provide the necessary range. This thesis proposes a compact radar system that meets both the SWaP and range requirements for UAS and can act as a standalone sensor for a sense and avoid system (SAA). The system meets the field of view requirements motivated by the UAS sensing problem (120deg x 30deg) and tracks targets in range and azimuthal angle using a four element phased array receiver. The phased array receiver implements real time correlation and beamforming using a field programmable gate array (FPGA) and can track multiple targets simultaneously. Excluding antennas, the radar transceiver and signal processing platform weighs approximately 120g and is approximately the size of a whiteboard eraser (2.25in x 4in x 1in), which meets the payload requirements of many small (<25kg) UAS. To our knowledge, this is the first real time phased array radar that meets the sensing and SWaP requirements for small UAS.Our testing was done with the radar system on the ground, aimed at airborne UAS targets. Using antennas with a gain of 12 dB, and 800 milliwatts of transmitted power, the system detects UAS targets with a radar cross section of less than 0.1 square meters up to 150 meters away. The ground based system demonstrates radar detectability of extremely small UAS targets, and is scalable to further ranges by increasing antenna gain or adding additional elements. Based on our success in detecting airborne UAS, we conclude that radar remains a feasible option for a UAS collision avoidance sensor.
48
Chiang, Ying-Chieh y 蔣英傑. "The digital implementation of FMCW Radar". Thesis, 2001. http://ndltd.ncl.edu.tw/handle/57115386135495625591.
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碩士國立雲林科技大學
電機工程系碩士班
89
[ABSTRACT] The main purpose of this thesis is to investigate the possibilities of noise and interference removal of a specific FMCW Radar. The discussion consists of three topics. The first is to develop an algorithm for the measurement of target distance and speed. The second topic involves the application of adaptive filter to remove or cancel various noises, which interfere with detection of the targets. The objective of the third topic is to solve the problem of co-channel interference, which usually causes the false alarms. Altogether, this study solves various problems that the FMCW Radar encounters. We also improve the Radar’s performance in speed and distance measurement by DSP technology. Keyword: FMCW Radar, Digital filters, Doppler effect, Fast Fourier Transform.
49
Chen, Li-Wei y 陳立偉. "Circuit Design of FMCW Level Radar". Thesis, 2005. http://ndltd.ncl.edu.tw/handle/57276663548701506373.
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碩士國立臺灣大學
電信工程學研究所
93
The content of this thesis is based on the principle of FMCW radar to design and implement the level radar circuits. Level radar is used to measure the liquid level in chemical tanks, and thereby counts the amount of the content. The radar RF signal is generated from a VCO with frequency from 4.5GHz to 4.75GHz, then gives to 9GHz to 9.5GHz through a multiplier, for radiation from the antenna. The radar received signal is then mixed with the transmitted signal to give a Doppler frequency signal to be processed by a counter to yield with the level distance. In Chapter 2, description on the FMCW radar principle and the schematics of level radar are presented. Chapter 3 describes the characteristics of each component, circuit design, layout, circuit implementation, and measurement results of power divider and attenuator. Chapter 4 then describes the test and measurement results in each step of assembling, and the measured results of a distant object. Chapter 5 is the conclusion.
50
Lin, Chien-Yi y 林芊宜. "Development of FMCW Radar System Simulator". Thesis, 2018. http://ndltd.ncl.edu.tw/handle/2m4af5.
Texto completoResumen
碩士國立交通大學
電信工程研究所
107
In this thesis, we discuss millimeter wave radar system using FMCW techniques. The simulation is carried out by numerical computing software, Matlab, and try to analyze the operation of actual radar system and the situations in real world. In this paper, the chirp waveform is used as transmitted signal model. Moreover, stretch processing and fast Fourier transform are used to detect the target’s distance and velocity. The simulation results are divided into three part. First, how to get best range resolution and velocity resolution. Second, we focus on the influence of the phase noise in radar system. Finally, we analyze the maximum tolerance phase angle to keep velocity undistorted.