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Dissertations / Theses on the topic 'Radar Detection'
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Lane, Andrew. "Real-time weather radar correlation using a vertically pointing radar." Thesis, University of Salford, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.244841.
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Kasebzadeh, Pedram. "Clutter Detection in Radar Applications." Thesis, Linköpings universitet, Institutionen för datavetenskap, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-171547.
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Radars have been used for detection purposes in safety applications (i.e., blind spot detection radar in cars) extensively. The existing detection methods, however, are not flawless. So far, the main focus of these methods is on detecting an object based on its reflectiveness. In this thesis, the limitation of conventional methods are addressed, and alternative approaches are proposed. The main objective is to model/identify the noise with statistical and machine learning approaches as an alternative to conventional methods that focus on the object. The second objective is to improve the time efficiency of these methods. The data for this thesis contains measurements collected from radars at ABB AB, Sweden. These measurements reflect the received signal strength. These radars are meant to be used in safety applications, such as in industrial environments. Thus, the trade-off between accuracy and complexity of the algorithms is crucial. One way to ensure there is nothing but noise in the surveillance field of the radar is to model the noise only. A new input can then be compared to this model and be classified as noise or not noise (object). One-class classifiers can be employed to approach this problem as they only need noise for training; hence they have been one of the initial proposals in this thesis. Alternatively, binary classifiers are investigated to classify noise and object given a new input data. Moreover, a mathematical model for noise is computed using the Fourier series expansion. While the derived model holds useful information in itself, it can be used, e.g., for hypothesis testing purposes. Furthermore, to make the classification more time-efficient, dimension reduction methods are considered. Feature extraction has been performed for this purpose with the help of the derived noise model. In order to evaluate the performance of the considered methods, three different datasets have been formed. In the first dataset,
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Kim, Jungwhan John. "Road detection on radar imagery." Thesis, Virginia Polytechnic Institute and State University, 1985. http://hdl.handle.net/10919/53080.
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A facet based road network detection procedure is described for radar imagery. The procedure includes a line detection part and a road detection and connection part. The line detection part analytically detects linear features using a facet Valley finding technique. Valleys are defined as zero crossings of the first directional derivatives of a bicubic facet model taken in a direction extremizing the second directional derivative. The road detection and connection part statistically screens the linear features on a component by component basis, and then optimally connects the screened linear features using a dynamic programming algorithm.
This thesis also includes as a preprocessing technique for noisy images, an adaptive noise removal algorithm, and suggests a practical method of estimating a local noise variance.Master of Science
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Ahmed, Atheeq. "Human Detection Using Ultra Wideband Radar and Continuous Wave Radar." Thesis, Linköpings universitet, Kommunikationssystem, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-137996.
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A radar works by radiating electromagnetic energy and detecting the reflected signal returned from the target. The nature of the reflected signal provides information about the target’s distance or speed. In this thesis, we will be using a UWB radar and a CW radar to help detect the presence and rough location of trapped survivors by detecting their motions. Range is estimated in the UWB radar using clutter removal with SVD and for the dual frequency CW Radar using STFT and median filtering. The effect of the algorithm parameters on their performance was analyzed. The performance of the implemented algorithms with regards to small motion detection, distance estimation and penetration capability was analyzed. Both systems are certainly capable of human detection and tracking.
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Jahangir, Mohammed. "Coherent radar clutter statistics." Thesis, University College London (University of London), 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.313422.
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O'Donoughue, Nicholas A. "Stochastic Time Reversal for Radar Detection." Research Showcase @ CMU, 2011. http://repository.cmu.edu/dissertations/178.
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Time Reversal is an adaptive waveform transmission technique particularly suited to dispersive or non-homogenous media that focuses energy on a desired point in space. Early work concentrated on optical and acoustic/ultrasonic applications, followed more recently by applications in the electromagnetic domain. Time Reversal has been used for single- and multi-antenna detection, imaging, communications, non-destructive testing, and beam steering, among other applications.
This thesis develops Time Reversal detection algorithms for randomly varying targets embedded in randomly varying clutter. We model the target and clutter as independent complex Gaussian random variables and consider both single-antenna and multi-antenna detection scenarios. We derive the optimal Time-Reversal Likelihood Ratio Test (TR-LRT) for the single-antenna case, as well as a sub-optimal Time Reversal-Linear Quadratic (TR-LQ) detector that allows for a priori threshold and performance computation. These detectors are compared against a benchmark Weighted Energy Detector (WED). For the multi-antenna scenario, we present the Time Reversal MIMO (TR-MIMO) detector and compare its performance to a conventional Spatial MIMO (S-MIMO) radar. We show that, for both scenarios, the relative performance of Time Reversal detection methods depends on the coherence of the channel between the forward and TR transmission stages. We discuss the potential for detection gains with Time Reversal in single-antenna and multi-antenna systems. We discuss lower and upper bounds on gain and show that Time Reversal provides a useful and computationally simple approximation to the optimal transmit signal.
To compute the optimal hypothesis test for a Blind TR detection system, we derive a new statistical distribution, the Complex Double Gaussian distribution, which characterizes the complex product Z = XY of independent complex Gaussian random variables X and Y . We also apply this new probability distribution to analyze the performance of M-ary Phase Shift Keying (MPSK) communication systems, showing its applicability well beyond the realm of Time Reversal problems.
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Coe, Godfrey. "Radar studies of the aurora." Thesis, University of Leicester, 1985. http://hdl.handle.net/2381/35859.
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The investigation of the high-latitude aurora by means of the V.H.F. auroral radar SABRE, (Swedish And British auroral Radar Experiment), developed by the Leicester University Ionospheric Physics group, is described. The first two chapters review previous studies of the atmosphere by radar techniques and includes a description of the SABRE radar. The basic radar equation and velocity relationships are derived and the various loss factors examined. From analysis of the echo signal data for the diffuse aurora, and examination of signal data from a radio star, the SABRE radar parameters are established. An investigation is then undertaken of the variation of the electrojet parameters, (derived from application of the radar equation to the SABRE data), with height, electric field strength and geomagnetic conditions. Evidence is found of backscattering from irregularities generated by both two-stream and gradient drift processes. An examination is also made of the echo signals detected at relatively short ranges, of below 370 km, and several causal mechanisms are investigated including scattering processes in the neutral atmosphere. It is evident that aircraft are predominantly the cause of these short-range echoes. This investigation also reveals a number of software and hardware faults in the initial radar configuration. This Thesis is concluded with suggestions for future development of the radar system, which include the implementation of a height-finding facility and improved spectral resolution.
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Rossler, Carl W. Jr. "Adaptive Radar with Application to Joint Communication and Synthetic Aperture Radar (CoSAR)." The Ohio State University, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=osu1366144863.
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Sexton, G. "Ground probing radar signal processing techniques." Thesis, University of Newcastle Upon Tyne, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.354404.
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Ballard, James Philip. "Radar range profile ship signature classification." Thesis, University College London (University of London), 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.272157.
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Odhiambo, George Samuel Obonyo. "Bayesian reconstruction of subsurface radar images." Thesis, University of York, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.296717.
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Stadelman, Dennis LeRoy Weiner Donald D. "Coherent radar detection in non-Gaussian clutter." Related electronic resource: Current Research at SU : database of SU dissertations, recent titles available full text, 2004. http://wwwlib.umi.com/cr/syr/main.
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Doyuran, Ulku. "Radar Target Detection In Non-gaussian Clutter." Phd thesis, METU, 2007. http://etd.lib.metu.edu.tr/upload/3/12608899/index.pdf.
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In this study, novel methods for high-resolution radar target detection in non-Gaussian clutter environment are proposed. In solution of the problem, two approaches are used: Non-coherent detection that operates on the envelope-detected signal for thresholding and coherent detection that performs clutter suppression, Doppler processing and thresholding at the same time. The proposed non-coherent detectors, which are designed to operate in non-Gaussian and range-heterogeneous clutter, yield higher performance than the conventional methods that were designed either for Gaussian clutter or heterogeneous clutter. The proposed coherent detector exploits the information in all the range cells and pulses and performs the clutter reduction and thresholding simultaneously. The design is performed for uncorrelated, partially correlated and fully correlated clutter among range cells. The performance analysis indicates the superiority of the designed methods over the classical ones, in fully correlated and partially correlated situations. In addition, by design of detectors for multiple targets and making corrections to the conventional methods, the target-masking problem of the classical detectors is alleviated.
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Bilgi, Akdemir Safak. "An Overview Of Detection In Mimo Radar." Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/12612589/index.pdf.
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In this thesis study, an overview of MIMO radar is presented. The differences in radar cross section, channel and received signal models in different MIMO radar configurations are examined. The performance improvements that can be achieved by the use of waveform diversity in coherent MIMO radar and by the use of angular diversity in statistical MIMO radar are investigated. The optimal detector under Neyman-Pearson criterion for Coherent MIMO radar when the interfering signal is white Gaussian noise is developed. Detection performance of phased array radar, coherent MIMO radar and Statistical MIMO radar are compared through numerical simulations. A detector for MIMO radar that contains the space time codes explicitly is also examined.
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Ihlen, Morten. "Automatic Detection for MTI Processed Radar Signals." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for elektronikk og telekommunikasjon, 2011. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-13846.
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In this thesis, methods for automatic detection for radar systems are investigated. The objective is to indicate the presence of targets in the midst of noise and clutter. One of the most efficent methods for doing this is to exploit the Doppler shift in reflections from moving targets. This is called Moving Target Indication (MTI), and it is used in many radar applications today. However, such functionality is not typical for radars employing a magnetron oscillator. The magnetron oscillator is widely used in civil marine radars, and MTI processing is of interest for such radars as well. In addition to MTI processing, automatic detection may be applied in order to make decisions on target presence. This may be achieved by employing Constant False Alarm Rate (CFAR) detection and pulse integration. The challenges with automatic detection are prediction of the clutter power, and handling of non-homogeneous environments. Ideally, clutter components will be removed by the MTI process, leaving receiver noise and reflection from targets at the output. However, this is not necessarily the case when applied to a magnetron radar. A particular automatic detector employing Ordered Statistics (OS) CFAR and binary pulse integration is investigated. This is a robust detector that may operate in the presence of multiple targets and non-Gaussian clutter. The binary integrator contributes in reducing the false alarm rate, such that acceptable performance may be achieved. In order to find suitable parameters for the detector, analysis of an MTI processed radar signal containing reflection from waves at sea and a small boat is carried out. Also, the performance of the detector has been measured in terms of false alarm probability, and target detection. Analysis shows that Weibull or K-distribution are suitable models for the sea clutter, and that the MTI signal exhibits spatial correlation between clutter samples. The correlation is concluded to be the reason for degradation in performance, as detection on clutter appears as targets. Also, optimum parameters for the detector is found, and it is shown that increasing the number of reference samples increases the number of target detections.
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Van, Vleck Teresa. "Ground penetrating radar in tree root detection /." Connect to resource, 1999. http://hdl.handle.net/1811/28577.
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Nazir, Mahvish. "Automotive radar target detection using ambiguity function." Thesis, University of Birmingham, 2016. http://etheses.bham.ac.uk//id/eprint/6842/.
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The risk of collision increases, as the number of cars on the road increases. Automotive radar is an important way to improve road traffic safety and provide driver assistance. Adaptive cruise control, parking aid, pre-crash warning etc. are some of the applications of automotive radar which are already in use in many luxury cars today. In automotive radar a commonly used modulation waveform is the linear frequency modulated continuous waveform (FMCW); the return signal contains the range and velocity information about the target related through the beat frequency equation. Existing techniques retrieve target information by applying a threshold to the Fourier power spectrum of the returned signal, to eliminate weak responses. This method has a risk of missing a target in a multi-target situation if its response falls below the threshold. It is also common to use multiple wide angle radar sensors to cover a wider angle of observation. This results in detecting a large number of targets. The ranges and velocities of targets in automotive applications create ambiguity which is heightened by the large number of responses received from wide angle set of sensors. This thesis reports a novel strategy to resolve the range-velocity ambiguity in the interpretation of FMCW radar returns that is suitable for use in automotive radar. The radar ambiguity function is used in a novel way with the beat frequency equation relating range and velocity to interpret radar responses. This strategy avoids applying a threshold to the amplitude of the Fourier spectrum of the radar return. This novel radar interpretation strategy is assessed by a simulation which demonstrates that targets can be detected and their range and velocity estimated without ambiguity using the combined information from the radar returns and existing radar ambiguity function.
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Christiansen, Jonas Myhre. "Fully adaptive radar for detection and tracking." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1587093543249087.
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Butler, Joseph MacKay. "Tracking and control in multi-function radar." Thesis, University College London (University of London), 1998. http://discovery.ucl.ac.uk/1317909/.
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The phased array multi-function radar is an effective solution to the requirement for simultaneous surveillance and multiple target tracking. However, since it is performing the jobs usually undertaken by several dedicated radars its radar time and energy resources are limited. For this reason, and also due to the large cost of active phased array antennas, it is important for the strategies adopted in the control of the radar to be efficient. This thesis investigates and develops efficient strategies for multi-function radar control and tracking. Particularly the research has focused on the use of rotating array antennas and simultaneous multiple receive beam processing. The findings of the research challenge the traditional view that three or four fixed (static) array faces is the best antenna configuration for a multi-function radar system. By developing novel methods for the comparison of systems utilising different antenna configurations it is shown that a rotating array multi-function radar performs the surveillance function with a greater efficiency in its use of radar time than a static array system. Also, a rotating array system benefits from the ability to distribute the radar resources over the angular coverage in a way that is impossible with a static array system. A novel strategy is presented to achieve this, which allows the rotating array system to better support the realistic situation of a high concentration of radar tasks in a narrow angular sector. It is shown that the use of broadened transmit beams coupled with simultaneous multiple narrow receive beams can eliminate the compromise on radar beamwidth between the surveillance and tracking functions that is associated with multi-function radars. This technique would allow construction of multi-function radar systems with narrow beamwidths, giving improved tracking performance, without extending search frame times excessively. Efficient tracking strategies for both static array and rotating array multi-function radars are developed. They are applied through computer simulation to demonstrate tracking of highly manoeuvrable targets with a narrow beam multi-function radar. Track robustness is attained through the use of multiple beam track updating strategies at little cost in terms of radar time.
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Griffiths, Hugh Duncan. "Studies of radar altimetry over topographic surfaces." Thesis, University College London (University of London), 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.284293.
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Gürbüz, Sevgi Zübeyde. "Radar detection and identification of human signatures using moving platforms." Diss., Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/37210.
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Radar offers unique advantages over other sensors for the detection of humans, such as remote operation during virtually all weather and lighting conditions, increased range, and better coverage. Many current radar-based human detection systems employ some type of Fourier analysis, such as Doppler processing. However, in many environments, the signal-to-noise ratio (SNR) of human returns is quite low. Furthermore, Fourier-based techniques assume a linear variation in target phase over the aperture, whereas human targets have a highly nonlinear phase history. The resulting phase mismatch causes significant SNR loss in the detector itself. In this work, human target modeling is used to derive a more accurate non-linear approximation to the true target phase history. Two algorithms are proposed: a parameter estimation-based optimized non-linear phase (ONLP) detector, and a dictionary search-based enhanced optimized non-linear phase (EnONLP) detector. The ONLP algorithm optimizes the likelihood ratio over the unknown model parameters to derive a more accurate approximation to the expected human return. The EnONLP algorithm stores expected target signatures generated for each possible combination of model parameters in a dictionary, and then applies Orthogonal Matching Pursuit (OMP) to determine the optimal linear combination of dictionary entries that comprises the measured radar data. Thus, unlike the ONLP, the EnONLP algorithm also has the capability of detecting the presence of multiple human targets. Cramer-Rao bounds (CRB) on parameter estimates and receiver operating characteristics (ROC) curves are used to validate analytically the performance of both proposed methods to that of conventional, fully adaptive STAP. Finally, application of EnONLP to target characterization is illustrated.
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Shtarkalev, Bogomil Iliev. "Single data set detection for multistatic Doppler radar." Thesis, University of Edinburgh, 2015. http://hdl.handle.net/1842/10556.
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The aim of this thesis is to develop and analyse single data set (SDS) detection algorithms that can utilise the advantages of widely-spaced (statistical) multiple-input multiple-output (MIMO) radar to increase their accuracy and performance. The algorithms make use of the observations obtained from multiple space-time adaptive processing (STAP) receivers and focus on covariance estimation and inversion to perform target detection. One of the main interferers for a Doppler radar has always been the radar’s own signal being reflected off the surroundings. The reflections of the transmitted waveforms from the ground and other stationary or slowly-moving objects in the background generate observations that can potentially raise false alarms. This creates the problem of searching for a target in both additive white Gaussian noise (AWGN) and highly-correlated (coloured) interference. Traditional STAP deals with the problem by using target-free training data to study this environment and build its characteristic covariance matrix. The data usually comes from range gates neighbouring the cell under test (CUT). In non-homogeneous or non-stationary environments, however, this training data may not reflect the statistics of the CUT accurately, which justifies the need to develop SDS methods for radar detection. The maximum likelihood estimation detector (MLED) and the generalised maximum likelihood estimation detector (GMLED) are two reduced-rank STAP algorithms that eliminate the need for training data when mapping the statistics of the background interference. The work in this thesis is largely based on these two algorithms. The first work derives the optimal maximum likelihood (ML) solution to the target detection problem when the MLED and GMLED are used in a multistatic radar scenario. This application assumes that the spatio-temporal Doppler frequencies produces in the individual bistatic STAP pairs of the MIMO system are ideally synchronised. Therefore the focus is on providing the multistatic outcome to the target detection problem. It is shown that the derived MIMO detectors possess the desirable constant false alarm rate (CFAR) property. Gaussian approximations to the statistics of the multistatic MLED and GMLED are derived in order to provide a more in-depth analysis of the algorithms. The viability of the theoretical models and their approximations are tested against a numerical simulation of the systems. The second work focuses on the synchronisation of the spatio-temporal Doppler frequency data from the individual bistatic STAP pairs in the multistatic MLED scenario. It expands the idea to a form that could be implemented in a practical radar scenario. To reduce the information shared between the bistatic STAP channels, a data compression method is proposed that extracts the significant contributions of the MLED likelihood function before transmission. To perform the inter-channel synchronisation, the Doppler frequency data is projected into the space of potential target velocities where the multistatic likelihood is formed. Based on the expected structure of the velocity likelihood in the presence of a target, a modification to the multistatic MLED is proposed. It is demonstrated through numerical simulations that the proposed modified algorithm performs better than the basic multistatic MLED while having the benefit of reducing the data exchange in the MIMO radar system.
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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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Rouhani, Shahin. "Radar and Thermopile Sensor Fusion for Pedestrian Detection." Thesis, Linköping University, Department of Electrical Engineering, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-115.
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During the last decades, great steps have been taken to decrease passenger fatality in cars. Systems such as ABS and airbags have been developed for this purpose alone. But not much effort has been put into pedestrian safety. In traffic today, pedestrians are one of the most endangered participants and in recent years, there has been an increased demand for pedestrian safety from the European Enhanced Vehicle safety Committee and the European New Car Assessment Programme has thereby developed tests where pedestrian safety is rated. With this, detection of pedestrians has arised as a part in the automotive safety research.
This thesis provides some of this research available in the area and a brief introduction to some of the sensors readily available. The objective of this work is to detect pedestrians in front of a vehicle by using thermoelectric infrared sensors fused with short range radar sensors and also to minimize any missed detections or false alarms. There has already been extensive work performed with the thermoelectric infrared sensors for this sole purpose and this thesis is based on that work.
Information is provided about the sensors used and an explanation of how they are set up during this work. Methods used for classifying objects are given and the assumptions made about pedestrians in this system. A basic tracking algorithm is used to track radar detected objects in order to provide the fusion system with better data. The approach chosen for the sensor fusion is a central-level fusion where the probabilities for a pedestrian from the radars and the thermoelectric infrared sensors are combined using Dempster-Shafer Theory and accumulated over time in the Occupancy Grid framework. Theories that are extensively used in this thesis are explained in detail and discussed accordingly in different chapters.
Finally the experiments undertaken and the results attained from the presented system are shown. A comparison is made with the previous detection system, which only uses thermoelectric infrared sensors and of which this work continues on. Conclusions regarding what this system is capable of are drawn with its inherent strengths and weaknesses.
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Celebi, Duygu. "Improvement Of Radar Detection By Doppler Pattern Matching." Master's thesis, METU, 2006. http://etd.lib.metu.edu.tr/upload/12607611/index.pdf.
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In this thesis, improvement of Cell Averaging Constant False Alarm Rate (CA CFAR) radar processors is studied. A new improvement method is proposed that will reduce probability of false alarm while keeping probability of detection at good values. This method makes use of Doppler spreading patterns that appear after Doppler processing. Therefore this method is called Doppler Pattern Matching (DPM).
Performance of the algorithm has been investigated by Monte Carlo simulations. In order to evaluate the performance, improvement factor is calculated which is the ratio of the probability of false alarm of original detector to the false alarm of improved detector. It is observed that improvement factor changes depending on the simulation scenario. Almost in every case, good improvement factor can be obtained. Moreover, in most of the cases, there has been no reduction in probability of detection after DPM is applied to CA CFAR detector.
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Amin, Shoaib, and Imran Mehmood. "DETECTION OF MULTIPLE TARGETS USING ULTRA-WIDEBAND RADAR." Thesis, Högskolan i Gävle, Avdelningen för elektronik, matematik och naturvetenskap, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-9374.
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In recent years, ultra-wideband (UWB) radars are gaining popularity in the radar field mainly inindustrial and commercial areas. The UWB radar has the potential of dramatically improving thecontrol and surveillance of industrial processes in confined areas.The report provides an introduction to radar systems and detail working principle of M-sequenceUWB radar and methodology of how detection of targets is carried out. First two chapters of thereport describes the working of radar systems and M-sequence radar whereas in the later part ofthe report, different detection algorithms are discussed which has been implemented in thepresent radar simulations. In conventional radar the main detection algorithm is matched filteringwhere the transmitted signal is correlated with the received signal. Whereas UWB signal is nonsinusoidalthat is vulnerable to change in its shape during entire radar operation. This is thereason, the traditional signal processing methods like matched filtering or correlation process arenot advisable for UWB signals. Therefore, a different detection scheme known as Inter-periodcorrelation process (IPCP) has been studied.IPCP technique had been implemented and a comparison was made with the conventional targetdetection algorithm. On the basis of comparison made in this project, it has been observed thatthe conventional target detection methods are not effective in case of M-sequence UWB radar.The simulation results shows that by implementing IPCP method, performance close to 8-bitADC can be achievable with 1-bit comparator, also with IPCP implementation system resolutioncan be enhance effectively.Main focus was to analyze how close the system can detect two targets, therefore in all themeasurements i.e. practical and simulated measurements, only two targets were used.
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Wasniewski, Flavio. "Detection of man made targets using radar polarimetry." Thesis, University of British Columbia, 2007. http://hdl.handle.net/2429/32130.
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Since the late 1970's, various synthetic aperture radar (SAR) satellite missions have provided a valuable source of information about the earth's surface. Providing their own illumination, these sensors generate imagery of our planet 24 hours a day, regardless of cloud cover. Until recently, except for the short term space shuttle SIR-C system, these SAR missions carried single-polarized sensors, meaning that the information extracted from the imagery, and the resulting quality of interpretation, was limited. In 2006 the first of a series of planned satellites carrying fully polarimetric SAR sensors was launched. In polarimetric SAR systems, images can be acquired with horizontal (H) and vertical (V) polarizations of the electric field on both transmission and reception. The resulting multipolarized imagery makes available a higher level of information content for a number of applications, including man made target detection. The potential of polarimetric SAR for man made target detection is investigated in this thesis. In the man made target detection field, the purpose is to differentiate the signature of the targets from those of adjacent natural areas. The most operationally successful application in this field is ship detection, as the sea surface usually forms a quite homogeneous and easily distinguishable clutter. Vegetated surfaces, however, usually constitute a more challenging clutter, as the backscatter levels can be very high and the signatures diverse, often being confused with those of man made targets. A few algorithms have been developed with the purpose of separating the targets from clutter. A methodology that employs the following three algorithms was recently tested in order to discriminate crashed aircraft from the surrounding terrain: Polarimetric Whitening Filter (PWF), Even Bounce Analysis and Cameron Decomposition. In these tests, successful results were achieved when the terrain was composed of a homogeneous field of grass and the targets were crashed airplanes. In this work the same methodology is tested with different man made targets and with different clutters. Also, methodologies involving the use of two other algorithms are tested in order to reduce the false alarm rates. These algorithms are Coherence Test of the Symmetric Scattering Characterization Method (SSCM) and Freeman-Durden Decomposition. The methodologies are applied to three different data sets acquired over different Canadian locations - Ottawa (ON), Gagetown (NB) and Vancouver (BC) - with the CV-580 polarimetric SAR system and the false alarm rates are assessed. Results show that the Coherence Test can lower false alarm rates on high vegetation clutter when applied in combination with other algorithms, while Freeman-Durden Decomposition does not perform effectively in the same experiments.Applied Science, Faculty of
Electrical and Computer Engineering, Department of
Graduate
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Wilchek, Lori-Ann. "Ground penetrating radar for detection of rock structure." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0013/MQ59900.pdf.
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Abujarad, Fawzy. "Ground penetrating radar signal processing for landmine detection." [S.l.] : [s.n.], 2007. http://diglib.uni-magdeburg.de/Dissertationen/2007/fawabujarad.htm.
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Wei, Wei. "Automatic surface targets detection in forward scatter radar." Thesis, University of Birmingham, 2018. http://etheses.bham.ac.uk//id/eprint/7965/.
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The purpose of this thesis is to apply automatic detection techniques on forward scatter radar for ground targets detection against vegetation clutter background and thermal noise. This thesis presents the FSR automatic detection performance analysis of three signal processing algorithms: coherent, non-coherent and cross-correlation. The concept of a CFAR forward scatter radar detection is presented and includes pre-fixed threshold detection and adaptive threshold detection. The developments of a set of simulation methods for target detection and performance analysis are described in details. In the results, we will compare the probability of detection for both human and vehicle target against a variety of clutter backgrounds - WGN, stationary narrow band clutter, non-stationary narrow band clutter, and real recorded vegetation clutter at a low (VHF and UHF) frequency bands. Finally, the advantages and limitations of detection performance for each signal processing algorithms are described.
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Davidson, Glen. "Doppler filtering and detection strategies for multifunction radar." Thesis, University College London (University of London), 2001. http://discovery.ucl.ac.uk/1382011/.
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This thesis concerns the analysis and processing of sea clutter from a Multiband Pulsed Radar - a land based research system operated by the British Defence Evaluation and Research Agency. This radar serves as a model for a class of Multi Function Radars (MFR) that offer extensive computer controlled adaptive operation. A fast Sequential Edge Detector (SED) is formulated which, accounting for locally exponential speckle, allows the spatial inhomogeneity within a scene to be segmented. This simultaneously identifies high intensity areas and the noise dominated shadowed regions of the scene using an adaptively sized analysis window. The high resolution data is thus shown to contain discrete scatterers which exist in addition to the compound modulation from the wave surface. The discrete component means the measured statistics cannot be considered homogenous or stationary. This is crucial for high resolution MFR as a priori information can no longer be relied upon when viewing a scene for the first time in order to make a detection decision. Considering the returns to be discrete in nature leads to a potential Doppler detection scheme operable at low velocities within the clutter spectrum. A physically motivated test statistic, termed persistence, is demonstrated based upon the lifetime of scattering events determined via the Continuous Wavelet Transform. When operated in coastal regions at low resolution, strong returns from the land-sea interface (edges) are expected which will seriously degrade the performance of radar detection models tuned to homogenous scenes. Explicit operational bounds are determined for the strength of these edges which show that simultaneous operation of an edge detector is required when assessing compound statistics such as the K-distribution using typical texture estimators. Additionally a method for accurately determining the N-sum PDF of K-distributed statistics within noise is constructed using a numerical inverse Laplace transform. The SED is also applied to Synthetic Aperture Sonar data to detect the large shadows cast by targets rather than their point intensity.
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Paulus, Audrey S. "Improved target detection through extended-dwell, multichannel radar." Diss., Georgia Institute of Technology, 2014. http://hdl.handle.net/1853/54279.
Full textAbstract:
The detection of weak, ground-moving targets can be improved through effective utilization of additional target signal energy collected over an extended dwell time. The signal model used in conventional radar processing limits integration of signal energy over an extended dwell. Two solutions that consider the complexity of the extended-dwell signal model and effectively combine signal energy collected over a long dwell are presented. The first solution is a single-channel algorithm that provides an estimate of the optimal detector to maximize output signal-to-interference-plus-noise ratio for the extended dwell time signal. Rather than searching for the optimal detector in an intractably large filter bank that contains all combinations of phase components, the single-channel algorithm projects dictionary entries against the data to estimate the signal’s linear and nonlinear phase components sequentially with small, phase-specific dictionaries in a multistage process. When used as the detector, the signal model formed from the estimated phase components yields near optimal performance for a wide range of target parameters for dwell times up to four seconds. In comparison, conventional radar processing methods are limited to an integration time of approximately 100 milliseconds. The second solution is a multichannel, multistage algorithm based on element-space pre-Doppler space-time-adaptive processing with two modifications that make it suitable for detection of weak targets whose energy is collected over an extended dwell time. The multichannel solution detects targets with lower radial velocities at significantly lower signal-to-noise ratios (SNRs) than conventional radar processing methods. The decrease in required input SNR for the multichannel solution as compared to conventional methods nearly doubles the detection range for a typical target of interest. Future related research includes extension of these concepts to other radar applications and investigation of algorithm performance for the multiple-target scenario.
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Benson, Stephen R. "Adaptive Thresholding for Detection of Radar Receiver Signals." Wright State University / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=wright1287692780.
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Ellinger, John David. "Multi-Carrier Radar for Target Detection and Communications." Wright State University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=wright1463839176.
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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.
Full textAbstract:
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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Bruyere, Donald Patrick. "Enhanced Detection of Ground Targets by Airborne Radar." Diss., The University of Arizona, 2008. http://hdl.handle.net/10150/195341.
Full textAbstract:
This dissertation deals with techniques that enhance the detection of ground targets by airborne radar. The methods employed deal with the problem of air to ground detection by breaking the problem into two broad categories. The first category deals with improving detection of moving targets by using space-time adaptive processing (STAP) in a multistatic configuration. Mult-static STAP provides increased detection performance by observing targets from multiple perspectives. Multiple viewing perspectives afford more opportunities to the combined system for observing radial velocity of the target more directly, thus increasing Doppler that helps distinguish the target from background clutter. Detection performance also improves through an increased number of independent observations of a target, which reduces the likelihood of the target fading for the combined system. Increasing detection performance by increasing the number of independent observations is referred to in communications theory as channel diversity. The second part of this dissertation deals with the problem of distinguishing stationary targets from background clutter within a Synthetic Aperture Radar image. Stationary target discrimination is accomplished by exploiting the statistical nature of multifaceted metallic objects within a scene. The performance improvement for both moving and non-moving improvement methods is characterized and compared to other systems that attempt to accomplish the same end using different means.
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Meats, Christopher Edward. "Use of ground probing radar on archaeological sites." Thesis, University of Oxford, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.296924.
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Vizinho, A. "Modern spectral analysis in HF radar remote sensing." Thesis, University of Sheffield, 1998. http://etheses.whiterose.ac.uk/3462/.
Full textAbstract:
High-Frequency (HF) radar systems are currently used to collect wave data. By applying spectral analysis methods, such as the Fast Fourier Transform (FFT) method, to the radar backscatter from the ocean surface, the so-called Doppler spectrum is calculated, and from this the directional wave spectrum and wave measurements are obtained. Because of the random nature of the ocean surface, spectral measurements are subject to random variability. In order to reduce variability, and hence to obtain relatively precise estimates, each spectrum is usually calculated by averaging a number of FFT estimates. Naturally, this method requires long data series, and problems may arise. In rapidly varying sea conditions, for example, successive FFT estimates may be quite inconsistent with each other (in non-stationary conditions), and then the spectrum estimate obtained by averaging is not only difficult to interpret but it may also be distorted. It is known that the more recent spectral analysis methods such as methods based on autoregressive (AR) and autoregressive-moving average (ARMA) stochastic models can provide stable estimates from short data sets. Thus these methods are potentially good alternatives to the FFT, as they avoid problems inherent to the use of large data sets. The aim of this thesis is to investigate how some of the modem spectral analysis methods may be used to obtain reliable spectral estimates from small data sets. Unlike the FFT method, the AR- and ARMA-based methods presuppose specific parametric forms for the spectral function, and therefore consist in estimating certain parameters from the data (as opposed to estimating the function itself). The modified covariance method and Burg's method are among several methods of estimating the parameters of the spectral function.
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Palmer, James E. "Utilising airborne bistatic radar for target detection and imaging /." [St. Lucia, Qld.], 2007. http://adt.library.uq.edu.au/public/adt-QU20070522.154133/index.html.
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Armstrong, Brian Clement. "Processing techniques for improved radar detection in spiky clutter." Thesis, University College London (University of London), 1992. http://discovery.ucl.ac.uk/1317536/.
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The problem of improved radar detection of targets embedded in spiky clutter is addressed. Two main areas where improvements may be possible are investigated, namely improved clutter suppression by doppler filtering, and improved Constant False Alarm Rate (CFAR) processing. The clutter suppression performance of several doppler processors is quantified under a wide range of conditions. It is shown that in spatially homogeneous clutter ideal optimal (Hsiao) filters offer 2 to 3 dB higher improvement factor than conventional techniques. Adaptive Hsiao filters are evaluated under conditions of spatially heterogeneous clutter, and it is shown that practical losses due to filter adaptivity and spectral heterogeneity will outweigh the superior performance of ideal Hsiao filters in homogeneous clutter. It is concluded that improved doppler filtering offers little scope for improving detection performance in spiky clutter, and that more significant benefits are to be gained through improved CFAR processing. The performance of three current generation CFAR processors is evaluated in spatially uncorrelated K-distributed clutter to quantify detection losses. It is shown that losses of in excess of 10 dB can be expected in spiky clutter. Reducing the loss by exploitation of any spatial correlation of the underlying clutter power is investigated. To this end a mathematically rigorous model for spatially correlated K-distributed clutter is derived. An improved CFAR processor based on optimal weighting of reference cells is formulated and evaluated. It is shown that in highly correlated clutter CFAR loss can be reduced by 2 to 5 dB compared to Cell Averaging CFAR processors. An alternative "RDT-CFAR" processor is formulated to eliminate reliance on spatial correlation, and this is shown to reduce CFAR loss by more than 10 dB in spectrally homogeneous spiky clutter. However, an increase in false alarm rate in clutter without constant spectrum is demonstrated. The RDT-CFAR processor has been modified to eliminate dependence on surrounding range bins. The resulting "δ-CFAR" processor reduces CFAR loss by more than 10 dB in even moderately spiky clutter. It is also immune to extraneous targets and clutter edges, and its false alarm performance is insensitive to clutter spikiness.
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Haché, Joseph Jean Pierre. "Probability of detection for a GO CFAR radar processor using envelope detection approximation /." Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1994. http://handle.dtic.mil/100.2/ADA286211.
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Hache, Joseph Jean Pierre. "Probability of detection for a GO CFAR radar processor using envelope detection approximation." Thesis, Monterey, California. Naval Postgraduate School, 1994. http://hdl.handle.net/10945/28467.
Full textAbstract:
The greatest-of logic for a constant false alarm rate processor (GO CFAR) is a commonly used method for the adaptive setting of a radar detection threshold in the presence of clutter edges. Instead of using a true envelope detector x = I2 + Q2, which is difficult to implement, envelope detection approximations of the form Xe = aMax (I),(Q) + bMin (I),(Q) and xe = a(I)+b(Q) (no Max and Min operators) where a and b are constants, are often used to detect a signal decomposed into its in-phase (I) and quadrature (Q) components. Closed form expressions are derived for the probability density function (pdf) of a radar range cell containing a detected target signal in the presence of noise using both approximations. These can then be used to calculate the probability of detection (PD). They can also be used to calculate the probability of false alarm (PFA) if the means of I and Q are set to zero. Closed form expressions are obtained analytically and by curve-fitting the numerically derived pdf of the target cell. Finally, using Monte Carlo techniques, this thesis also compares the GO CFAR detection performance using envelope detection approximations xe, xe and the true envelope detector x for zero mean white Gaussian noise input samples I and Q
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Razzaghi, Elyas, and Hoek Arno Van. "Micro-Shivering Detection : Detection of human micro-shivering using a 77 GHz radar." Thesis, Högskolan i Halmstad, Akademin för informationsteknologi, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-39807.
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Radars have been under steady development to track, identify, image, and classify targets. Modern radar systems, with the help of embedded systems, have additional comprehensive signal processing capabilities. They can extract useful information from very noisy data, e.g. interference from the environment and unwanted echoes which is collectively known as clutter in radar terms. Concerning the healthcare industry, radar applications for detection of vital signs, i.e. breathing and heart rate, have been extensively developed during the last few decades. Modern radar systems are expected to be a large part of non-intrusive monitoring in the coming smart home industry, where vital signs need to be monitored in the currently aging population. The research presented here is to break new ground in the radar-based healthcare technology, enabling detection of cold-induced shivering to such level that the micro-shivering can be clearly identified. To simplify the radar software optimization, a commercially available radar kit with demo application and a muscle model system using a vibration generator is used. The model is quantified through precise measurements. A simulated human body vital sign plus shivering is applied. By optimizing the radar software, the shivering amplitude and frequency are measured.
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Claassen, Daniel Marthinus. "Electromagnetic characterization of a wideband borehole radar imaging system." Thesis, University of Oxford, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.296786.
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Redfern, Anthony. "Radar simulator training for effective maritime search and rescue." Thesis, University of Plymouth, 1987. http://hdl.handle.net/10026.1/2213.
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The main effort in locating and rescuing survivors of a maritime incident is borne by merchant shipping. This research shows that search and rescue is a task that will face most seafarers, but as they generally lack the necessary levels of skill and knowledge required the task will often be poorly performed. A remedy to this unsatisfactory situation lies in proper training and guidance for ships' officers. This thesis evaluates, using illuminative techniques, the first simulator course devised to provide such training. The evaluation will be of particular use to others called upon to provide similar training. It also shows a requirement for the adoption of improved procedures in merchant ship searches, makes relevant recommendations, and identifies areas for further research. More significantly the study has allowed, through simulation, an opportunity unparalleled in the real situation to assess the guidance contained in the Merchant Ship Search and Rescue Manual (MERSAR). This International Maritime Organization manual is the primary aid available to seafarers facing search and rescue responsibilities. The assessment concludes there is scope for extensive amendment to MERSAR amounting to overall rather than piecemeal revision. Positive recommendations are made, particularly in the areas of communications, control and co-ordination. It is anticipated that this original research will have an important role to play in MERSAR's revision, and through this improve the effectiveness of maritime search and rescue.
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Myers, Theodore J. "Determination of Bragg Scatter in an Aircraft Generated Wake Vortex System for Radar Detection." Diss., Virginia Tech, 1997. http://hdl.handle.net/10919/30719.
Full textAbstract:
Remote detection and tracking of wingtip generated wake vortices is important for hazard avoidance especially near airports. Aircraft that fly through these hazardous vortices experience sudden induced roll. Experiments have demonstrated that there is sufficient radar cross section for remote detection at frequencies ranging from VHF to C band (100 MHz to 5 GHz).
The mechanism that yields this radar cross section is Bragg scattering from the index of refraction variations due to the atmospheric water vapor and potential temperature fields being mixed by the wake vortex system.
Refractive index variations of the size that correspond to half the operating radar wavelength produce the observed radar return. Previous analysis has postulated turbulence within the wake vortex to be the generator of the index of refraction variations.
In this work, a new mechanism is identified that does not assume turbulence within the wake vortex system. This "laminar flow mechanism" causes refractive index structuring that stretches into successively smaller spirals over time as the wake vortex system swirls and descends through the stratified atmosphere.
The results are quantitatively consistent with experimental data. Results indicate that this new mechanism has a sharply peaked doppler spectrum which is encouraging for coherent detection by doppler radar.Ph. D.
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Zheng, Yuanxing. "Microsatellite radar altimeter payload design for global sea state monitoring." Thesis, University of Surrey, 2000. http://epubs.surrey.ac.uk/843200/.
Full textAbstract:
A detailed understanding of the relationship between altimetry measurement, especially significant wave height (SWH) measurement, and phase distortion is still unclear. Therefore, the objective of this Ph.D. study is first to outline this relationship by a simulation using a model that considers the errors from both the signal source and the power amplifier. The simulation results show the power amplifier influence is more significant than that of signal source in SWH estimation, and that the phase errors influence is worse for lower SWH conditions. It is recommended from the simulation that the group delay error of the whole transmitter link, after the chirp generator, should be well controlled to be under 0.5ns. In the payload design, Class-F is chosen as the amplifier operation mode due to its high efficiency and fewer harmonic frequency components. The difference between the operational principles of second and third harmonic peaking Class-F amplifiers have been illustrated by the simulation. Both of them can achieve high efficiency and high gain, however the third harmonic peaking Class-F is simpler to implement. Therefore it was chosen by the final design. In the simulation, a large signal STATZ model is set up, followed by the S-band Class-F amplifier design simulation and the implementation of third harmonic peaking Class-F amplifier. Based on this, an adaptive feedback group delay equalizer is proposed as a solution for the phase error compensation within the whole chirp signal swept bandwidth. A very simple but effective phase error detection and calculation circuit is designed, built and measured. The test branch results are very satisfying. Its small size and lower power consumption makes it very suitable for a compact microsatellite environment. In summary, the possibility of a medium resolution microsatellite borne radar altimeter for optimising shipping routes is investigated in this study. A 12 satellites constellation is proposed for achieving near real time altimetry broadcasting. The key payload design problems are identified in a thorough feasibility study: the restriction corresponding to these main problems is quantified via the SWH estimation simulation. A feedback linearization method is proposed as a promising solution for the compact microsatellite design with high power efficiency requirements, demonstrated by both simulation and hardware implementation results.
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Munu, Mbalu. "Tracking algorithms with variable update time for phased array radar." Thesis, University of Nottingham, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.239456.
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Hughes, E. J. "Radar cross section modelling using genetic algorithms." Thesis, Department of Aerospace and Sensors, 2009. http://hdl.handle.net/1826/3263.
Full textAbstract:
In the design of new, more sophisticated missile systems, simulations need to be
realistic and fast. Realistic target models are just as important as realistic models
of the missile, but have often been overlooked in the past. Existing methods for
creating realistic target models require considerable computational resources. This
thesis addresses the problem of using limited resources to create realistic target
models for simulating engagements with radar guided homing missiles.
A multiple genetic algorithm approach is presented for converting inverse synthetic
aperture radar images of targets into scatterer models. The models produced
are high fidelity and fast to process. Results are given that demonstrate the generation
of a model from real data using a desktop computer.
Realistic models are used to investigate the effects of target fidelity on the
missile performance. The results of the investigation allow the model complexity
to be traded against the fidelity of the representation to optimise simulation speed.
Finally, a realistic target model is used in a feasibility study to investigate the
potential use of glint for target manoeuvre detection. Target glint is considered as
noise in conventional missile systems and filtered to reduce its effects on the
tracking performance- The use of glint for target manoeuvre detection would
provide a cheap and novel alternative to the optical techniques currently being
developed. The feasibility study has shown that target manoeuvre detection using
glint may be as fast as optical techniques and very reliable.
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Matos, Diogo Silva. "Person detection system." Master's thesis, Universidade de Aveiro, 2017. http://hdl.handle.net/10773/23853.
Full textAbstract:
mestrado em Engenharia Eletrónica e TelecomunicaçõesO RADAR é para fins militares já relativamente antigo que sofreu um grande impulso durante a Segunda Guerra Mundial. Hoje em dia existe um forte desenvolvimento no RADAR em aplicações de navegação ou vigilância/segurança. Esta dissertação surge no seguimento destas novas aplicações, em que se pretende o desenvolvimento de um RADAR de baixo custo que permita ao utilizador detetar pessoas, bem como, os seus movimentos através de paredes ou objetos opacos. O desenvolvimento deste RADAR recaiu em tecnologias emergentes como antenas adaptativas e rádio definido por software que permitem uma grande versatilidade e adaptação em termos de aplicações. A utilização de um RADAR com múltiplas entradas e múltiplas saídas fornece uma maior diversidade de informação que garante mais probabilidades de deteção. A aplicação de técnicas digitais de beamforming, possibilita conhecer a posição e o movimento da pessoa. Com a implementação destas técnicas um protótipo capaz de detetar pessoas e os seus movimentos através de paredes e tijolos foi desenvolvido com sucesso solucionando o problema inicial. Na fase de projeto de RADAR houve necessidade de caracterizar a propagação de ondas de rádio em materiais de construção, como tijolos e madeira, medindo-se a sua atenuação. Deste modo foi possível fazer o balanço de potencia para varios canarios.
The RADAR is already relatively old for military purposes that underwent a major development during World War II. Nowadays there is a strong development in RADAR in navigation or surveillance/security applications. This dissertation follows on from these new applications, which aim to develop a low cost RADAR that allows the user to detect people as well as their movements through walls or opaque objects. The development of this RADAR has relied on emerging technologies such as adaptive antennas and SDR that allow for great versatility and adaptation in terms of applications. The use of a MIMO RADAR provides a greater diversity of information that guarantees more probabilities of detection and the application of digital techniques of beamforming, allows to know the position and the movement of the person. With the implementation of these techniques a prototype capable of detecting people and their movements through walls and bricks was successfully developed solving the initial problem. In the RADAR design phase it was necessary to characterize the propagation of radio waves in building materials, such as bricks and wood, by measuring their attenuation. In this way it was possible to perform the power balance for several scenarios.