Journal articles: 'Radio frequency spectrum analyzer'

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Lavielle, V., I. Lorgeré, J. L. Le Gouët, S. Tonda, and D. Dolfi. "Wideband versatile radio-frequency spectrum analyzer." Optics Letters 28, no. 6 (March 15, 2003): 384. http://dx.doi.org/10.1364/ol.28.000384.

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Corcoran, Bill, Trung D. Vo, Mark D. Pelusi, Christelle Monat, Dan-Xia Xu, Adam Densmore, Rubin Ma, Siegfried Janz, David J. Moss, and Benjamin J. Eggleton. "Silicon nanowire based radio-frequency spectrum analyzer." Optics Express 18, no. 19 (September 7, 2010): 20190. http://dx.doi.org/10.1364/oe.18.020190.

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Ferrera, Marcello, Christian Reimer, Alessia Pasquazi, Marco Peccianti, Matteo Clerici, Lucia Caspani, Sai T. Chu, Brent E. Little, Roberto Morandotti, and David J. Moss. "CMOS compatible integrated all-optical radio frequency spectrum analyzer." Optics Express 22, no. 18 (August 28, 2014): 21488. http://dx.doi.org/10.1364/oe.22.021488.

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Ménager, Loïc, Ivan Lorgeré, Jean-Louis Le Gouët, Daniel Dolfi, and Jean-Pierre Huignard. "Demonstration of a radio-frequency spectrum analyzer based on spectral hole burning." Optics Letters 26, no. 16 (August 15, 2001): 1245. http://dx.doi.org/10.1364/ol.26.001245.

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Lavielle, V., F. De Seze, I. Lorgeré, and J. L. Le Gouët. "Wideband radio frequency spectrum analyzer: improved design and experimental results." Journal of Luminescence 107, no. 1-4 (May 2004): 75–89. http://dx.doi.org/10.1016/j.jlumin.2003.12.028.

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Chen, Liao, Yuhua Duan, Haidong Zhou, Xi Zhou, Chi Zhang, and Xinliang Zhang. "Real-time broadband radio frequency spectrum analyzer based on parametric spectro-temporal analyzer (PASTA)." Optics Express 25, no. 8 (April 13, 2017): 9416. http://dx.doi.org/10.1364/oe.25.009416.

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Ma, Ming, Rhys Adams, and Lawrence R. Chen. "Integrated Photonic Chip Enabled Simultaneous Multichannel Wideband Radio Frequency Spectrum Analyzer." Journal of Lightwave Technology 35, no. 13 (July 1, 2017): 2622–28. http://dx.doi.org/10.1109/jlt.2017.2694003.

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Sabur, Fatmawati, and Ucok Sinaga. "Design Trainer Analysis Spectrum Analyzer Based on Raspberry Python and Register Transfer Level - Software Defined Radio." Airman: Jurnal Teknik dan Keselamatan Transportasi 3, no. 2 (February 4, 2021): 1–8. http://dx.doi.org/10.46509/ajtkt.v3i2.69.

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communication network. However, the high purchase price of a Spectrum Analyzer means that not everyone can afford it. One solution to overcome this problem is to make a piece of hardware capable of performing the same performance as a Spectrum Analyzer but at a relatively cheaper price. Prototype Spectrum Analyzer to be implemented is a device capable of displaying the spectrum of a signal in a certain frequency range. This engineering was carried out from July to October 2020 at the Makassar Aviation Polytechnic Campus and testing tools with a comparison tool was carried out at Otban Region V Makassar. The technique or method used in data collection is the library method by collecting some written data from books, literature, and tutorials on the internet, as reference material and then analyzing solutions that can be taken in solving problems. From the results of tests carried out by using RTL-SDR on the Single Board Computer (SBC), Raspberry pi can display the frequency spectrum whether it is done singly or applied to the network so that it can be used as a learning medium for wireless technology practice or other materials that measure frequency From sergi, the performance of the trainer spectrum analyzer with the use of raspberry pi as a device for processing radio / wireless signals is quite good at utilization with CLI mode (command line interface) but is relatively slow when used on the desktop as a portable spectrum analyzer that can be used as a learning medium

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Thohari, Afandi Nur Aziz, and Agfianto Eko Putra. "Rancang Bangun Spectrum Analyzer Menggunakan Fast Fouier Transform Pada Single Board Computer." IJEIS (Indonesian Journal of Electronics and Instrumentation Systems) 7, no. 1 (April 30, 2017): 71. http://dx.doi.org/10.22146/ijeis.16417.

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Spectrum analyzer is an instrument device to measure the magnitude of the frequency and the power of signal. It has many benefits, such as used for testing telecommunication devices, determining the allocation of unused frequencies and also for practicum in schools or universities. However, because of these many benefits, the price of this signal measuring equipment soared in the market.As an alternative, a device that can serve as spectrum analyzer yet has an affordable price is invented in the form of the prototype of spectrum analyzer built using a single board computer by applying a fast Fourier transform algorithm. Feedback from the prototype is in the form of radio signal captured using RTL-SDR.The test results showed that the range of frequencies that can be displayed by the prototype is 24 MHz to 1.769 MHz. Then the test results of fast Fourier transform computing on N points showed that the prototype can work smoothly using the N from 512 to 32.768 points. The use of N more than 32.768 points will cause CPU and disk memory overloaded and lead to a slow performance. Finally, comparison of the levels of spectrum was performed using spectrum analyzer Anritsu MS2720T. As a result, it is known that prototype can be used to show the location of the frequency spectrum of the radio signal appropriately.

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Duan, Yuhua, Liao Chen, Lei Zhang, Xi Zhou, Chi Zhang, and Xinliang Zhang. "Temporal radio-frequency spectrum analyzer, based on asynchronous optical sampling assisted temporal convolution." Optics Express 26, no. 16 (July 30, 2018): 20735. http://dx.doi.org/10.1364/oe.26.020735.

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Chipaux, M., L. Toraille, C. Larat, L. Morvan, S. Pezzagna, J. Meijer, and T. Debuisschert. "Wide bandwidth instantaneous radio frequency spectrum analyzer based on nitrogen vacancy centers in diamond." Applied Physics Letters 107, no. 23 (December 7, 2015): 233502. http://dx.doi.org/10.1063/1.4936758.

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Lorgeré, Ivan, Loïc Ménager, Vincent Lavielle, Jean-Louis Le Gouët, Daniel Dolfi, Sylvie Tonda, and Jean-Pierre Huignard. "Demonstration of a radio-frequency spectrum analyser based on spectral hole burning." Journal of Modern Optics 49, no. 14-15 (November 2002): 2459–75. http://dx.doi.org/10.1080/0950034021000011419.

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Pelusi, Mark, Feng Luan, Trung D. Vo, Michael R. E. Lamont, Steven J. Madden, Douglas A. Bulla, Duk-Yong Choi, Barry Luther-Davies, and Benjamin J. Eggleton. "Photonic-chip-based radio-frequency spectrum analyser with terahertz bandwidth." Nature Photonics 3, no. 3 (February 15, 2009): 139–43. http://dx.doi.org/10.1038/nphoton.2009.1.

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Vo, Trung D., Mark D. Pelusi, Jochen Schroder, Bill Corcoran, and Benjamin J. Eggleton. "Multi-Impairment Monitoring at 320 Gb/s Based on Cross-Phase Modulation Radio-Frequency Spectrum Analyzer." IEEE Photonics Technology Letters 22, no. 6 (March 2010): 428–30. http://dx.doi.org/10.1109/lpt.2010.2040979.

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Kaarthik, K., P. T. Sivagurunathan, and S. Sivaranjani. "A REVIEW ON SPECTRUM SENSING METHODS FOR COGNITIVE RADIO NETWORKS." JOURNAL OF ADVANCES IN CHEMISTRY 12, no. 18 (November 16, 2016): 5053–57. http://dx.doi.org/10.24297/jac.v12i18.5380.

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In Wireless Communication, Radio Spectrum is doing a vital role; for the future need it should use efficient. The existing system, it is not possible to use it efficiently where the allocation of spectrum is done based on fixed spectrum access (FSA) policy. Several surveys prove that it show the way to inefficient use of spectrum. An innovative technique is needed for spectrum utilization effectively. Using Dynamic spectrum access (DSA) policy, available spectrum can be exploited. Cognitive radio arises to be an attractive solution which introduces opportunistic usage of the frequency bands that are not commonly occupied by licensed users. Cognitive radios promote open spectrum allocation which is a clear departure from habitual command and control allocation process for radio spectrum usage. In short, it permits the formation of â€œinfrastructure-lessâ€ joint network clusters which is called Cognitive Radio Networks (CRN). Conversely the spectrum sensing techniques are needed to detect free spectrum. In this paper, different spectrum sensing techniques are analyzed.

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Bello, N., and K. O. Ogbeide. "Designing a Real-time Swept Spectrum Analyser with USRP B210." Nigerian Journal of Environmental Sciences and Technology 5, no. 2 (October 2021): 329–39. http://dx.doi.org/10.36263/nijest.2021.02.0275.

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Cognitive radio has received considerable amount of attention as a promising technique to provide dynamic spectrum allocation. Spectrum sensing is one of the basic functions in the cognitive radio and is crucial to all other functions. Software- defined radios (SDRs) are considered due to its very high flexibility and have become a common platform for CR implementation replacing expensive spectrum analysers. The most popular among various SDR platforms is the universal software-defined radio peripheral (USRP). This paper presents a real-time swept spectrum sensing solution based on USRP B210. It also presents a detailed explanation of the concept of energy detection and the methodology for wide-band sensing. Finally, the performance of the proposed sensing solution is analysed through FFT graphs and spectrogram plot taken for 8 hours. The results showed that the proposed sensing solution was capable of achieving high resolution in the frequency domain of the wide band measured which implies that wide bands with heterogenous signals like the ISM band can be accurately resolved and analysed.

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Cho, Chihyun, Hyunji Koo, Jae-Yong Kwon, Joo-Gwang Lee, and Tae-Weon Kang. "Measurement of Analog Modulation Index with a Calibrated Radio Frequency Attenuator." Journal of Electromagnetic Engineering and Science 21, no. 2 (April 30, 2021): 87–94. http://dx.doi.org/10.26866/jees.2021.21.2.87.

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This paper presents a method for the accurate and traceable measurement of the analog modulation index. A calibrated step attenuator was used as the main apparatus because it has a higher dynamic range and lower uncertainty than a spectrum analyzer or an oscilloscope. In amplitude modulation (AM), the modulation index is obtained from the amplitude difference between the carrier and the first sideband, as in the conventional method. The resolution and calibration uncertainties of the step attenuator were propagated to the measurement uncertainty of the modulation index. The uncertainty produced by the impedance mismatch and repeatability was also included. For frequency modulation (FM) and phase modulation (PM), the modulation index, β, was estimated (with the step attenuator) from the spectrum of each sideband through the nonlinear fitting of the Bessel function. Thus, the uncertainty of the fitting process was added to the uncertainty of the measurement. The three modulations, AM, FM, and PM, exhibited an expanded uncertainty (approximately 95% confidence level, k = 2) of 0.372% for 50% nominal depth of the AM, 88.8 Hz for the peak frequency deviation of 10 kHz, and 0.88 mrad for a 0.1 radian modulation index, respectively.

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Lorgeré, I., V. Crozatier, G. Gorju, F. Bretenaker, and J. L. Le Gouët. "Radio-frequency spectrum analyzers based on rare earth ion doped crystals." Applied Physics B 84, no. 4 (May 23, 2006): 653–57. http://dx.doi.org/10.1007/s00340-006-2263-5.

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Jayati, Ari Endang, Wahyu Minarti, and Sri Heranurweni. "Analisa Teknis Penetapan Kanal Frekuensi Radio Untuk Lembaga Penyiaran Radio Komunitas Wilayah Kabupaten Batang." Jurnal ELTIKOM 5, no. 2 (September 10, 2021): 73–80. http://dx.doi.org/10.31961/eltikom.v5i2.361.

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The radio frequency spectrum constitutes a limited and strategic natural resource with high economic value, so it must be managed effectively and efficiently to obtain optimal benefits by observing national and international legal principles. Radio Community Broadcasting Institution uses limited frequency allocation in three channels, namely, in the frequency channels 202 (107.7 MHz), 203 (107.8 MHz), and 204 (107.9 MHz), with limited transmit power and area coverage. The problem in this research is the frequency overlap with other community radios in an area. The issue raised is whether it is possible to establish a new community radio in the Batang Regency area by paying attention to existing radios that have licenses in districts/cities that are in the area directly adjacent to Batang Regency by considering the limited allocation of radio frequency channels community, without the occurrence of radio frequency interference with other community radios. The purpose of this research is to solve these problems. It is necessary to have a policy in determining radio frequency users to get good quality radio broadcast reception. The method used is to analyze the frequency determination technique based on the interference analysis on other community broadcasters. By using the Radio Mobile Software for frequency repetition simulation, in this research, the results show that Batang FM Community Radio does not allow to get frequency channels for community radio operations. After all, it interferes with the Service Area of Soneta FM Radio in Pekalongan City because it does not meet the requirements for determining the frequency channel = Eu> NF, namely the Nuisance Field (NF) value of 109.7 dB is greater than the Minimum Usable Field strength (Eu) of 66 dB. In comparison, Limpung FM Radio gets radio frequency on channel 203 (frequency 107.8 MHz) because it meets the requirements for determining the frequency channel = Eu> NF, namely the Minimum Usable Field strength (Eu) 66 dB greater than the Nuisance Field (NF) of 55.7 dB.

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Takács, Donát, Boldizsár Markotics, and Levente Dudás. "Processing and Visualizing the Low Earth Orbit Radio Frequency Spectrum Measurement Results From the SMOG Satellite Project." Infocommunications journal 13, no. 1 (2021): 18–25. http://dx.doi.org/10.36244/icj.2021.1.3.

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December 6, 2019, the second and third Hungarian satellites, SMOG-P and ATL-1 (both having been developed at the Budapest University of Technology and Economics) were launched. They both had a radio frequency spectrum analyzer on board, which was used to measure for the first time the strength of radio frequency signals radiated into space by terrestrial digital TV transmitters – that can be detected in orbit around the Earth. In this paper, we present how two- and three-dimensional radiosmog maps were created from raw data received from space. The goal of this paper is to demonstrate the process of creating these maps from the raw data collected; the analysis of the results visible in these maps is beyond the scope of the present discussion.

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Sharma, Ashok, Yichuang Sun, Oluyomi Simpson, and David Lauder. "Design and Implementation of a Reconfigurable Wideband Radio Frequency Spectrum Analyzer With Image Rejection in the Digital Domain." IEEE Transactions on Instrumentation and Measurement 70 (2021): 1–16. http://dx.doi.org/10.1109/tim.2021.3060578.

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Liu, Jing Xue, Zhi Bo Li, and Hong Li. "Dynamic Allocation of Radio Frequency in the Battlefield Environment." Applied Mechanics and Materials 197 (September 2012): 496–501. http://dx.doi.org/10.4028/www.scientific.net/amm.197.496.

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Dynamic allocation of Radio Frequency (Hereafter called “RF”) is critical in the battlefield spectrum management. The article analyzes the conventional method of RF dynamic allocation in the battlefield environment, and set up the mathematic model of the RF dynamic allocation by using the results of spectrum detected in battlefield. It designs the algorithms with the combination of Genetic Algorithms and Tabu Search Algorithms. The simulation experiment proves the high efficiency of hybrid algorithms and it suit for solving the RF dynamic allocation problem in the battlefield environment.

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Onic, D. "On the integrated continuum radio spectrum of supernova remnant W44 (G34.7-0.4): New insights from Planck." Serbian Astronomical Journal, no. 191 (2015): 29–37. http://dx.doi.org/10.2298/saj150715004o.

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In this paper, the integrated continuum radio spectrum of supernova remnant (SNR) W44 was analyzed up to 70 GHz, testing the different emission models that can be responsible for its particular shape. The observations by the Planck space telescope made it possible to analyze the high frequency part of radio emission from SNRs. Although the quality of radio continuum spectrum (a high scatter of data points at same frequencies) prevents us to make definite conclusions, the possibility of spinning dust emission detection towards this remnant is emphasized. In addition, a concave-down feature, due to synchrotron losses, can not be definitely dismissed by the present knowledge of the integrated radio continuum spectrum of this SNR.

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An, Fangxia, M. Vaccari, Ian Smail, M. J. Jarvis, I. H. Whittam, C. L. Hale, S. Jin, et al. "Radio spectral properties of star-forming galaxies in the MIGHTEE-COSMOS field and their impact on the far-infrared-radio correlation." Monthly Notices of the Royal Astronomical Society 507, no. 2 (August 9, 2021): 2643–58. http://dx.doi.org/10.1093/mnras/stab2290.

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ABSTRACT We study the radio spectral properties of 2094 star-forming galaxies (SFGs) by combining our early science data from the MeerKAT International GHz Tiered Extragalactic Exploration (MIGHTEE) survey with VLA, GMRT radio data, and rich ancillary data in the COSMOS field. These SFGs are selected at VLA 3 GHz, and their flux densities from MeerKAT 1.3 GHz and GMRT 325 MHz imaging data are extracted using the ‘superdeblending’ technique. The median radio spectral index is $\alpha _{\rm 1.3\, GHz}^{\rm 3\, GHz}=-0.80\pm 0.01$ without significant variation across the rest-frame frequencies ∼1.3–10 GHz, indicating radio spectra dominated by synchrotron radiation. On average, the radio spectrum at observer-frame 1.3–3 GHz slightly steepens with increasing stellar mass with a linear fitted slope of β = −0.08 ± 0.01, which could be explained by age-related synchrotron losses. Due to the sensitivity of GMRT 325 MHz data, we apply a further flux density cut at 3 GHz ($S_{\rm 3\, GHz}\ge 50\, \mu$Jy) and obtain a sample of 166 SFGs with measured flux densities at 325 MHz, 1.3 GHz, and 3 GHz. On average, the radio spectrum of SFGs flattens at low frequency with the median spectral indices of $\alpha ^{\rm 1.3\, GHz}_{\rm 325\, MHz}=-0.59^{+0.02}_{-0.03}$ and $\alpha ^{\rm 3.0\, GHz}_{\rm 1.3\, GHz}=-0.74^{+0.01}_{-0.02}$. At low frequency, our stacking analyses show that the radio spectrum also slightly steepens with increasing stellar mass. By comparing the far-infrared-radio correlations of SFGs based on different radio spectral indices, we find that adopting $\alpha _{\rm 1.3\, GHz}^{\rm 3\, GHz}$ for k-corrections will significantly underestimate the infrared-to-radio luminosity ratio (qIR) for >17 per cent of the SFGs with measured flux density at the three radio frequencies in our sample, because their radio spectra are significantly flatter at low frequency (0.33–1.3 GHz).

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Isingo, Fredrick, Prosper Mafole, and Abdi Abdalla. "Possibilities and Challenges of Radio Frequency Energy Harvesting in Dar es Salaam, Tanzania." Tanzania Journal of Engineering and Technology 39, no. 2 (December 31, 2020): 92–103. http://dx.doi.org/10.52339/tjet.v39i2.697.

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This paper presents investigation on the possibilities and challenges of harvesting ambient Radio Frequency Energy (RFE) at Dar es Salaam region in Tanzania. The Radio Frequency (RF) signals were measured using a Rohde and Schwarz FSC 3 spectrum analyzer observing available frequencies with their respective power. Among several RF signals received, the most powerful signals observed were; 800 MHz, 950 MHz, 2100 MHz and 2400 MHz, having average signal strengths of about -30.29 dBm, -35.94 dBm, -42.90 dBm and -30.42 dBm respectively. The power possessed within these frequencies were suitable to be harvested due to their signal strengths, an overall power average of -34.89dBm was obtained and a multi narrowband harvester was designed and simulated using real-time values on Keysight’s Advanced Design System (ADS) 2019. The simulation results confirm a promising possibility of harvesting RF energy to power ultra-low-power devices in the Internet of Things (IoT) and beyond.

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N. Eberechukwu, Paulson, Dauda S. Umar, Alias Mohd, Kamaludin M. Y., M. Adib bin Sarijari, and Rozeha A. Rashid. "Interference Temperature Measurements and Spectrum Occupancy Evaluation in the Context of Cognitive Radio." Indonesian Journal of Electrical Engineering and Computer Science 10, no. 3 (June 1, 2018): 1007. http://dx.doi.org/10.11591/ijeecs.v10.i3.pp1007-1012.

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<span lang="EN-MY">This paper presents a refined radio spectrum measurement platform specifically designed for spectrum occupancy surveys in the context of Cognitive radio. Cognitive radio permits the opportunistic usage of licensed bands by unlicensed users without causing harmful interference to the licensed user. In this work, a study based on the measurement of the 800 MHz to 2.4 GHz frequency band at two different locations inside Universiti Teknologi Malaysia (UTM), Johor Bahru campus, Malaysia is presented. Two Tektronix RSA306B spectrum analyzer are set up to conduct simultaneous measurements at different locations for a 24 hours period. The analysis conducted in this work is based on the real spectrum data acquired from environment in the experimental set up. Busy and idle channels were identified. The channels subject to adjacent-channel interference were also identified, and the impact of the detection threshold used to detect channel activities was also discussed. The consistency of the observed channel occupation over a range of thresholds and a sudden drop has good characteristics in determining an appropriate threshold needed in order to avoid interference.</span>

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Backus, Peter R., Sam LaRoque, Jill C. Tarter, John Dreher, Kent Cullers, Alan Patrick, and Gary Heiligman. "Studies of Radio Frequency Interference at Parkes Observatory." International Astronomical Union Colloquium 161 (January 1997): 661–66. http://dx.doi.org/10.1017/s0252921100015219.

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AbstractFrom February through early June, 1995, Project Phoenix conducted SETI observations of 209 stars over the frequency range from 1195 to 3005 MHz. A byproduct of this search is a unique data set suitable for studying the Radio Frequency Interference (RFI) environment at the Parkes 64-m telescope in New South Wales, Australia. RFI is an increasing problem for SETI and other radio astronomy observations conducted outside of the «protected» frequency bands. The data analyzed for this paper were «mean baseline» spectra in Left and Right Circular Polarization (LCP, RCP), integrated for either 138 or 276 s, covering a 10 MHz bandwidth with 15,552 channels at a resolution of 643 Hz. Channels were identified as contaminated by RFI when the power in the channel exceeded the mean noise by 3%. The «spectral occupancy», the fraction of time RFI was seen, was determined for each channel. The RFI occupancy for LCP and RCP are distinctly different. Approximately 100 MHz of the spectrum was too heavily contaminated for SETI observations.

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Dayana, R., and R. Kumar. "Modified isotropic orthogonal transform algorithm-universal filtered multicarrier transceiver for 5G cognitive radio application." International Journal of Electrical and Computer Engineering (IJECE) 9, no. 4 (August 1, 2019): 3100. http://dx.doi.org/10.11591/ijece.v9i4.pp3100-3107.

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Rapid developments in modern wireless communication permit the trade of spectrum scarcity. Higher data rate and wider bandwidth emerge the development in growing demand of wireless communication system. The innovative solution for the spectrum scarcity is cognitive radio (CR). Cognitive radio is the significant technology used to utilize the spectrum effectively. The important aspect of CR is sensing the spectrum band and detects the presence or absence of the primary user in the licensed band. Moreover, another serious issue in next generation (5G) wireless communication is to decide the less complex 5G waveform candidate for achieving higher data rate, low latency and better spectral efficiency. Universal filtered multi-carrier (UFMC) is one of the noticeable waveform candidates for 5G and its applications. In this article, we investigate the spectrum sensing methods in multi-carrier transmission for cognitive radio network applications. Especially, we integrate the sensing algorithm into UFMC transceiver to analyze the spectral efficiency, higher data rates and system complexity. Through the simulation results, we prove that the UFMC based cognitive radio applications outperform the existing Orthogonal Frequency Division Multiplexing (OFDM) based CR applications.

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Huang, Xu Fang, and Jing Kai Chen. "GNSS Signal Power Spectrum Density Analysis." Applied Mechanics and Materials 239-240 (December 2012): 603–7. http://dx.doi.org/10.4028/www.scientific.net/amm.239-240.603.

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The correct analysis of power spectrum density is very critical when assessing the radio frequency compatibility among GPS, Galileo and BD. Among a number of papers on this research, some, however, ignore the fact that short-code would produce line spectrum, and some present derivation results with errors. The above problems, instead, are given close attention by this paper. The paper firstly analyzes the characteristics of power spectral densities of Global Navigation Satellite Systems (GNSS) baseband signals, taking into account the real properties of the signals, such as code length, data rate, code chipping rate and characteristics of spreading code. And then it presents the detail derivation process. To verify the correctness of its results, GPS C/A code signal is taken as an example. The simulation of this research produces three results that include the line spectrum, real PSD and the spectral separation coefficient of C/A code in different data symbol period. It is concluded that the derivation results prove to be correct, and the data symbol period should be regarded as an important parameter of short code when assessing the radio frequency compatibility.

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Naim, Nani Fadzlina, Siti Noor Maslizan Sudin, Suzi Seroja Sarnin, Norsuzila Ya'acob, and Latifah Sarah Supian. "Design of fiber bragg grating (FBG) temperature sensor based on optical frequency domain reflectometer (OFDR)." International Journal of Electrical and Computer Engineering (IJECE) 10, no. 3 (June 1, 2020): 3158. http://dx.doi.org/10.11591/ijece.v10i3.pp3158-3165.

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In this paper, the simulation of Fiber Bragg Grating (FBG) as a temperature sensor is conducted. The FBG temperature sensor is designed based on Optical Frequency Domain Reflectometer (OFDR) concept. A continuous wave (CW) laser is used as the optical source and it is transmitted to two FBGs. The two FBGs reflection spectra will produce a beat frequency that can be detected using a Radio Frequency (RF) Spectrum Analyzer. Any temperature change will shift Bragg wavelength, thus produce a shift for the beat frequency. In this work, an FBG with temperature sensitivity 10 pm/˚C is employed. It is found that by using this technique, a high-resolution temperature sensor can be designed with temperature resolution of 0.1˚C.

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Cadena Muñoz, Ernesto, Luis Fernando Pedraza Martínez, and Cesar Augusto Hernandez. "Rényi Entropy-Based Spectrum Sensing in Mobile Cognitive Radio Networks Using Software Defined Radio." Entropy 22, no. 6 (June 6, 2020): 626. http://dx.doi.org/10.3390/e22060626.

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A very important task in Mobile Cognitive Radio Networks (MCRN) is to ensure that the system releases a given frequency when a Primary User (PU) is present, by maintaining the principle to not interfere with its activity within a cognitive radio system. Afterwards, a cognitive protocol must be set in order to change to another frequency channel that is available or shut down the service if there are no free channels to be found. The system must sense the frequency spectrum constantly through the energy detection method which is the most commonly used. However, this analysis takes place in the time domain and signals cannot be easily identified due to changes in modulation, power and distance from mobile users. The proposed system works with Gaussian Minimum Shift Keying (GMSK) and Orthogonal Frequency Division Multiplexing (OFDM) for systems from Global System for Mobile Communication (GSM) to 5G systems, the signals are analyzed in the frequency domain and the Rényi-Entropy method is used as a tool to distinguish the noise and the PU signal without prior knowledge of its features. The main contribution of this research is that uses a Software Defined Radio (SDR) system to implement a MCRN in order to measure the behavior of Primary and Secondary signals in both time and frequency using GNURadio and OpenBTS as software tools to allow a phone call service between two Secondary Users (SU). This allows to extract experimental results that are compared with simulations and theory using Rényi-entropy to detect signals from SU in GMSK and OFDM systems. It is concluded that the Rényi-Entropy detector has a higher performance than the conventional energy detector in the Additive White Gaussian Noise (AWGN) and Rayleigh channels. The system increases the detection probability (PD) to over 96% with a Signal to Noise Ratio (SNR) of 10dB and starting 5 dB below energy sensing levels.

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Kovalev, Y. Y., N. A. Nizhelsky, Yu A. Kovalev, G. V. Zhekanis, and A. V. Bogdantsov. "Survey and Analysis of 1-22 GHz Spectra for the Full Sample of 660 AGNs North of Declination −30°." International Astronomical Union Colloquium 184 (2002): 299–300. http://dx.doi.org/10.1017/s025292110003089x.

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AbstractMeasurements of broad-band 6-frequency 1-22 GHz spectra of 660 compact extragalactic radio sources were performed in 1997 (for declinations −30° < δ < + 43°) and 1998 (north of+49°) at RATAN-600. “Average rest-frame” statistical spectral shapes for different subsamples of sources are analyzed. These shapes and each spectrum observed can be represented as the sum of a spectrum of an extended optically thin component (magnetized envelope/lobe), constant or slowly variable and dominating at lower frequencies, and a spectrum of a compact component (relativistic jet), dominating at higher frequencies, with any type of variability. We have revealed specific radio features of the EGRET sub-sample; this favors the models suggesting a relation between the emission mechanisms in radio and gamma-ray ranges. Sources are sampled for which the most compact VLBI structure is expected.

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Bogod, V. M., S. M. Vatrushin, V. E. Abramov-Maximov, S. V. Tsvetkov, and V. N. Dikij. "Panoramic Analyzer of Radio Spectra — Instrument for Measurements of Coronal Magnetic Fields on the Sun." International Astronomical Union Colloquium 141 (1993): 306–9. http://dx.doi.org/10.1017/s0252921100029304.

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The study of solar radio emission in a wide (covering many octaves) wavelength range is of great importance for plasma diagnostics of all types of solar activity. Here we describe a new spectroanalyzer covering a wide range in frequency from 1 to 18 GHz, which is used at the RATAN-600 radio telescope beginning 1991 December 20. Coronal magnetic fields have been measured with the various radio astronomical methods presented in these proceedings by Gelfreikh et al. and Bogod et al.Of special value are collaborative spectral-polarization observations using the RATAN-600 and high-spatial resolution observations with the VLA and WSRT (Akhmedov et al. 1986; Bogod et al. 1992; Alissandrakis et al. 1992).

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Buhaiov, M. V., B. V. Molodetsky, I. O. Mykhailiuk, and V. V. Hordiichuk. "METHOD OF SIGNAL PARAMETERS ESTIMATION OF RADIOSTATIONS WITH FAST FREQUENCY HOPPING SPREAD SPECTRUM." Проблеми створення, випробування, застосування та експлуатації складних інформаційних систем, no. 17 (December 30, 2019): 14–26. http://dx.doi.org/10.46972/2076-1546.2019.17.02.

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Modern special-purpose radios utilize ultra-short burst mode with frequency hopping spread spectrum. Such digital radios operate, as a rule, in the fast frequency hopping spread spectrum mode and use a considerable number of frequency channels with frequency separation between adjacent channels, which is significantly less than the spectrum width of the frequency element. The main modulation in such radios is frequency manipulation. The identification of signals with fast frequency hopping spread spectrum and frequency manipulation is performed by estimating the speed of frequency tuning, the speed of information transmission, the number of frequency channels and the step of the frequency grid and comparing the obtained values with the corresponding characteristics of known radio stations with fast frequency hopping spread spectrum. The time limits and the duration of the frequency elements are calculated by the envelope of the received signal. For this purpose, a suitable method has been developed, which consists in filtering the envelope by means of a moving average window for suppression of the noise component and threshold processing. The threshold value is selected by the given probability of its exceeding by noise sample. The proposed approach to determining the time limits of frequency elements does not require any a priori signal information. To determine the frequencies of the frequency elements periodogram estimates are used. An exponential extrapolation of the discrete power spectrum was used to increase the frequency resolution at a fixed window length of the fast Fourier transform. It is shown that in order to uniquely determine the step of the frequency grid and the diversity of frequency manipulation frequencies, it is necessary to analyze the number of frequency elements not less than the number of frequency channels. By analyzing the histogram of the differences of sorted frequency vector of the frequency elements, determine the frequency grid, frequency diversity and the multiplicity of frequency manipulation. An approximate estimate of the number of frequency channels is calculated as the ratio of the magnitude of the frequency vector of the frequency elements to the step of the frequency grid. As a rule, symbol transmission at frequency manipulation is carried out at orthogonal frequencies, so it can be roughly assumed that the symbolic speed is equal to the frequency diversity of the frequency manipulation. The baud rate can be set only after signal demodulation and bit stream analysis, which can determine the frame structure and the number of service and information bits. The proposed method provides the estimation of the values of the parameters necessary for the identification of radio stations of signal parameters with a relative error not exceeding 0.3%, with values of signal to noise ratio not lower than 5 dB.

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d’Antonio, D., M. Giroletti, G. Giovannini, and A. Maini. "Radio spectral properties of cores and extended regions in blazars in the MHz regime." Monthly Notices of the Royal Astronomical Society 490, no. 4 (November 15, 2019): 5798–806. http://dx.doi.org/10.1093/mnras/stz2967.

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ABSTRACT Low-frequency radio surveys allow in-depth studies and new analyses of classes of sources that were previously known and characterized only in other bands. In recent years, low radio frequency observations of blazars have become available as a result of new surveys, such as the GaLactic and Extragalactic All-sky Murchison Widefield Array (MWA) survey (GLEAM). We search for gamma-ray blazars in a low-frequency (ν < 240 MHz) survey, to characterize the spectral properties of the spatial components. We cross-correlate GLEAM with the fourth catalogue of active galactic nuclei (4LAC) detected by the Fermi satellite. This improves on previous works by using a low-frequency catalogue that is wider and deeper, with a better spectral coverage and the latest and most sensitive gamma-ray source list. Compared with a previous study based on the commissioning survey, the detection rate increased from 35 to 70 per cent. We include data from the Australia Telescope 20-GHz (AT20G) survey in order to extract high-frequency high-angular resolution information about the radio cores of blazars. We find low radio frequency counterparts for 1274 out of 1827 blazars in the range of 72–231 MHz. Blazars have flat spectra at the ∼100-MHz regime, with a mean spectral index α = −0.44 ± 0.01 (assuming Sν ∝ να). Low synchrotron peaked objects have a flatter spectrum than high synchrotron peaked objects. Low frequency radio and gamma-ray emissions show a significant but scattered correlation. The ratio between lobe and core radio emission in gamma-ray blazars is smaller than previously estimated.

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Tian, Jian Hui, Bing Li, and Lian Jian. "The Research of Noise Characteristics on Shenzhen Metro Platform." Applied Mechanics and Materials 741 (March 2015): 426–30. http://dx.doi.org/10.4028/www.scientific.net/amm.741.426.

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The noise SPL and spectrum characteristics were tested and analyzed for the Shenzhen metro platform when the metro is inbound and outbound by using the noise and vibration measurement and analysis system. Time-domain SPL distribution diagrams shows, causing the largest noise level inside platform is mainly from the station radio, when no station radio, metro wheel-rail noise and air-conditioning fan noise have become a major SPL source in platform. The noise level at the platform is between 73dB-76dB. Frequency domain noise spectrum diagram shows, the noise SPL peak appeared in both low frequency and mid frequency ranges. Low frequency noise peak appears at 125Hz and 250Hz frequency band, mainly from the site of passengers talking and footsteps. Mid frequency noise peak is located in the 500Hz-1000Hz range, mainly from station radio, metro wheel-rail noise and air-conditioning fan and so on. This study provides a reference for noise reduction design of the metro platform.

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Gómez Vega, Carlos A., Carlos A. Gutiérrez, Jose J. Jaime Rodriguez, Javier Vazquez Castillo, Daniel U. Campos Delgado, Jose M. Luna Rivera, and Miguel A. Díaz Ibarra. "Doppler spectrum measurements of vehicular radio channels using a narrowband sounder." Revista Facultad de Ingeniería Universidad de Antioquia, no. 93 (August 23, 2019): 32–40. http://dx.doi.org/10.17533/10.17533/udea.redin.20190405.

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This paper describes the implementation of a narrowband sounder for Doppler power spectrum (DPS) measurements of vehicular communication channels. The narrowband channel sounder is implemented using general purpose equipment, making such measurement platform easy to replicate for didactic and research purposes. To demonstrate the practical value of this framework, a measurement campaign was conducted to obtain empirical information about the spectral characteristics of vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) multipath radio channels in the 700 MHz band. The collected data wasprocessed to compute the average Doppler shift and the Doppler spread of the measured channels. The obtained results show that the spectral properties of frequency-dispersive vehicular radio channels can be effectively analyzed using narrowband sounding principles.

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Kolyadenko, Yu Yu, О. V. Kolyadenko, and B. P. Mulyar. "Method for optimization of frequency resource allocation with frequency reuse for cognitive radio system." Radiotekhnika, no. 204 (April 9, 2021): 73–79. http://dx.doi.org/10.30837/rt.2021.1.204.08.

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The concept of cognitive radio can be described as a radio with the study of capabilities, i.e. as a radio that is able to gain knowledge about the radio environment and adjust its operating parameters and protocols accordingly. The task of minimizing the frequency band is relevant at the stage of the cognitive radio network functioning when distributing the frequency resource between subscriber stations. With the ever-growing demand for frequency bands, this challenge is driven by the need to improve the efficient use of the radio frequency spectrum through frequency reuse methods. This paper proposes a method for ensuring the reuse of frequencies based on obtaining estimates of mutual distances between subscriber stations in real time. An algorithm is proposed for solving the problem of frequency resource allocation optimization for a cognitive radio network with frequency reuse. The algorithm is based on the method of local optimization, one of the approximate methods of discrete programming. In this case, the condition of local optimality is that the operating frequency assigned to the next subscriber station must be the closest to the frequency assigned in the previous step. The efficiency of the frequency resource optimization algorithm for the LTE network was analyzed using simulation modeling. The dependences of the bandwidth on the number of subscriber stations served are obtained. The analysis showed that the use of this algorithm allows to reduce the frequency band by 2 -3 times. The analysis also showed that the efficiency of the algorithm increases with the growth of the number of subscriber stations served simultaneously.

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Mészárosová, Hana, Ján Rybák, Marian Karlický, and Karel Jiřička. "Separation of solar radio bursts in a complex spectrum." Proceedings of the International Astronomical Union 6, S274 (September 2010): 150–52. http://dx.doi.org/10.1017/s1743921311006788.

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AbstractRadio spectra, observed during solar flares, are usually very complex (many bursts and fine structures). We have developed a new method to separate them into individual bursts and analyze them separately. The method is used in the analysis of the 0.8–2.0 GHz radio spectrum of the April 11, 2001 event, which was rich in drifting pulsating structures (DPSs). Using this method we showed that the complex radio spectrum consists of at least four DPSs separated with respect to their different frequency drifts (−115, −36, −23, and −11 MHz s−1). These DPSs indicate a presence of at least four plasmoids expected to be formed in a flaring current sheet. These plasmoids produce the radio emission on close frequencies giving thus a mixture of superimposed DPSs observed in the radio spectrum.

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Oluwafemi, Ilesanmi B., Adedeji M. Faluru, and Tayo D. Obasanyo. "Radio frequency peak and average power density from mobile base stations in Ekiti State, Nigeria." Bulletin of Electrical Engineering and Informatics 10, no. 1 (February 1, 2021): 224–31. http://dx.doi.org/10.11591/eei.v10i1.1879.

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The ever-increasing number of mobile telecommunication base station as a result of increasing demand for broadband applications has raised a growing concern and worry over the health implications and safety of the radiations from these base stations by the resident of Ekiti State and Nigeria in Nigeria. Measurement of radio frequency was conducted in this research in order to study the electromagnetic field radiation level in Ekiti State Nigeria. Investigation was conducted with the four available mobile operators with the three sub-frequency band viz 900 MHz, 1800 MHz and 2100 MHz. The power density of radio frequency radiation was estimated through measurement with the aid of A 3-Axis RF Radiation Strength Meter TM-196 and Handheld Spectrum Analyzer Model NA-773, 144/430. The peak and average power density was computed using the method of theoretical calculation and the safety distance from the antennas were estimated. The measured and the calculated values were compared with the international commission on non-ionizing radiation protection (ICNIRP) standard for public and occupational exposure level. Results show that the radiations from the base stations adheres to the standard provided by ICNIRP

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Serhiienko, S. P., V. G. Krizhanovski, D. V. Chernov, and L. V. Zahoruiko. "Effective modes of operation of radio-bombing devices for covert information gathering in the field of noise interference." Radiotekhnika, no. 205 (July 2, 2021): 169–74. http://dx.doi.org/10.30837/rt.2021.2.205.18.

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The information security of modern society is in constant counteraction and constant improvement of technical means used for unauthorized information pickup, and technical means that prevent it. The paper analyzes examples of methods of applying noise interference to counteract the unauthorized pickup. The possibility of unauthorized pickup by passive radio devices using noise interferences is shown and analyzed using noise interferences, which are used to suppress the eavesdropping devices. The transfer of picked up information is possible both by radio wave and low-frequency channels using metal structures or water pipes. As a model of noise interference, a random narrow-band signal with a Gaussian distribution was used. The electrical model of the device was simulated by a transmission line with a high-frequency diode at its end. The idealized exponential dependence of the diode current on the voltage was used. The reflected wave spectra are obtained for different ratios of the transmission line resistance, the differential resistance of diode, and the external offset voltage at the diode. The modes and features of analog and digital information transmission by the radio tab device using energy of radio noises are analyzed. In the radio tab device, the information is transmitted by reflected wave, the spectrum of which is distorted at a nonlinear element placed at the end of transmission line. An analysis of the device operation was carried out along the full possible frequency range associated with the spectrum of the incident noise interference. The optimal elements parameters for the passive electrical circuit are calculated: the resistance of the transmission line, the differential resistance of the diode, the offset voltage, and the modulation mode, depending on the frequency range in which the leak is possible.

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Chen, Joy, and Lu-Tsou Yeh. "Optimization of Citizen Broadband Radio Service Frequency Allocation for Dynamic Spectrum Access System." December 2020 2, no. 4 (January 5, 2021): 143–48. http://dx.doi.org/10.36548/jsws.2020.4.001.

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With the increase in mobile broadband utilization, more spectrum release is recommended by the Federal Communications Commission for spectrum sharing under a three-tire system called Citizens Broadband Radio Service. The standardization, functional and operational necessities of this framework are defined by the Wireless Innovation Forum. If an unavoidable shipborne radar appears on the channel, the channel must be vacated by the lower tier users. The timing constraints on CBRS is also stringent. Wireless stations transmit short beacon frames termed as heartbeat signals. These signals consist of the wireless channel encryption data, Service Set Identifier (SSID) and other credential data. These signals also transmit commands to vacate a channel. The heartbeat interval, timing constraint and domain proxy features are analyzed in this paper. CBSD renunciation and spectrum acquisition is performed with the help of domain proxy based communication. The CBRS-SAS channel allocation algorithm is further investigated. The communication interoperability and network robustness can improved with the introduction of secondary SAS and secondary domain proxy respectively.

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Saleh, Mohammed Mehdi, Ahmed A. Abbas, and Ahmed Hammoodi. "5G cognitive radio system design with new algorithm asynchronous spectrum sensing." Bulletin of Electrical Engineering and Informatics 10, no. 4 (August 1, 2021): 2046–54. http://dx.doi.org/10.11591/eei.v10i4.2839.

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Due to the rapid increase in wireless applications and the number of users, spectrum scarcity, energy consumption and latency issues will emerge, notably in the fifth generation (5G) system. Cognitive radio (CR) has emerged as the primary technology to address these challenges, allowing opportunist spectrum access as well as the ability to analyze, observe, and learn how to respond to environmental 5G conditions. The CR has the ability to sense the spectrum and detect empty bands in order to use underutilized frequency bands without causing unwanted interference with legacy networks. In this paper, we presented a spectrum sensing algorithm based on energy detection that allows secondary user SU to transmit asynchronously with primary user PU without causing harmful interference. This algorithm reduced the sensing time required to scan the whole frequency band by dividing it into n sub-bands that are all scanned at the same time. Also, this algorithm allows cognitive radio networks (CRN) nodes to select their operating band without requiring cooperation with licensed users. According to the BER, secondary users have better performance compared with primary users.

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Fomin, Vladislav V., Artūras Medeišis, and Daiva Vitkutė-Adžgauskienė. "IN SEARCH OF SUSTAINABLE BUSINESS MODELS FOR COGNITIVE RADIO EVOLUTION." Technological and Economic Development of Economy 18, no. 2 (June 29, 2012): 230–47. http://dx.doi.org/10.3846/20294913.2012.663415.

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In this paper we examine the emerging industry of Cognitive Radio/Software Defined Radio (CR/SDR), a sector which in some ways seconds the industry structure of the cellular mobile communications, while bearing distinctive characteristics. Any radio telecommunications infrastructure depends on scarce resources – radio frequency spectrum – that require policy decisions for allocation to specific countries and services. CR/SDR may constitute a new paradigm in radio communications as it may completely or partially eliminate the role of the regulator in minutiae of spectrum access authorization. In this paper, we review scarce literature on CR/SDR to analyze the relationships between political, technological and economic factors in order to identify drivers and barriers to the emergence of new techno-economic paradigm of CR/SDR. Our discussion of business opportunities for CR/SDR includes analysis of applicable spectrum access policies and identification of those of them, which would be most fertile for the development of future CR/SDR business.

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Fellahi, Abdelhatif El, Aurélien Mazzamurro, Jean Claude Gerbedoen, Yannick Dusch, Olivier Bou Matar, Phillippe Pernod, Abdelkrim Talbi, and Nicolas Tiercelin. "Miniaturized Coplanar Waveguide for Nanostructured Magnetostrictive Multilayer Characterization." Proceedings 2, no. 13 (January 17, 2019): 851. http://dx.doi.org/10.3390/proceedings2130851.

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A miniaturized coplanar waveguide (CPW) on a Y-cut LiNbO3 substrate operating in Radio Frequency region (RF) is proposed for studying of magnetostrictive multi-layered structure. The structure is composed of a 14 × [TbCo2 (3.7 nm)/FeCo (4 nm)] nanostructured multi-layer. Using microtechnology process, the miniaturized CPW has been designed with a 50 µm wide signal line in the frequency range from 6 MHz to 6 GHz. Electromagnetic simulations based on ®Ansys/HFSS demonstrate insertion losses less than 2 dB and show that the magnetic field is more confined in the nanostructured multi-layer placed on top of the micro-sized CPW. By using Vectorial Network Analyzer (VNA) the Ferromagnetic Resonance (FMR) is investigated from the reflection (Sii) or transmission (Sij) coefficients of scattering parameters. An inversion model is finally used to extract the complex permeability spectrum of the thin-film in a large frequency range.

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Wasilewska, Małgorzata, and Hanna Bogucka. "Machine Learning for LTE Energy Detection Performance Improvement." Sensors 19, no. 19 (October 8, 2019): 4348. http://dx.doi.org/10.3390/s19194348.

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The growing number of radio communication devices and limited spectrum resources are drivers for the development of new techniques of dynamic spectrum access and spectrum sharing. In order to make use of the spectrum opportunistically, the concept of cognitive radio was proposed, where intelligent decisions on transmission opportunities are based on spectrum sensing. In this paper, two Machine Learning (ML) algorithms, namely k-Nearest Neighbours and Random Forest, have been proposed to increase spectrum sensing performance. These algorithms have been applied to Energy Detection (ED) and Energy Vector-based data (EV) to detect the presence of a Fourth Generation (4G) Long-Term Evolution (LTE) signal for the purpose of utilizing the available resource blocks by a 5G new radio system. The algorithms capitalize on time, frequency and spatial dependencies in daily communication traffic. Research results show that the ML methods used can significantly improve the spectrum sensing performance if the input training data set is carefully chosen. The input data sets with ED decisions and energy values have been examined, and advantages and disadvantages of their real-life application have been analyzed.

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Jacobson, A. R., R. Holzworth, and X. M. Shao. "Low-frequency ionospheric sounding with Narrow Bipolar Event lightning radio emissions: energy-reflectivity spectrum." Annales Geophysicae 26, no. 7 (June 27, 2008): 1793–803. http://dx.doi.org/10.5194/angeo-26-1793-2008.

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Abstract. We analyze data on radio-reflection from the D-region of the lower ionosphere, retrieving the energy-reflection coefficient in the frequency range ~5–95 kHz. The data are the same as developed for a recent study of ionospheric-reflection height, and are based on recordings of powerful (multi-Gigawatt) radio emissions from a type of narrow (~10 μs) lightning discharge known as "Narrow Bipolar Events". The sequential appearance of first the groundwave signal, and then the ionospheric single-hop reflection signal, permits us to construct the energy-reflection ratio. We infer the energy reflection's statistical variation with solar zenith angle, angle-of-incidence, frequency, and propagation azimuth. There is also a marginally-significant response of the energy reflectivity to solar X-ray flux density. Finally, we review the relationship of our results to previous published reports.

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Paramonov, A. A., and Van Zung Hoang. "Joint use of frequency-time division and antinoise coding in radio communication systems with FHSS." Russian Technological Journal 9, no. 4 (August 26, 2021): 77–84. http://dx.doi.org/10.32362/2500-316x-2021-9-4-77-84.

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In the context of continuous improvement of radio prospecting and active radio jamming technics along with introduction of automated active countermeasures systems (ACS), the frequency-hopping spread spectrum (FHSS) radio communication systems (RCS) are widely used in order to improve reliability and noise immunity of data transmission. The noise immunity of the RCS affected by unintentional or deliberate interference can be significantly perfected by the combined use of frequency-time division and antinoise coding. This paper explores the case when the interference created by an ACS system with a limited transmitter power covers a part of the RCS frequency range. The receiver gets input mix of the wanted signal, the receiver noise, and probably a deliberate interference also considered as a noise. The article analyzes the noise immunity of signals reception with FHSS in the low-speed radio systems with joint use of frequency-time division of information subsymbols and noise combating codes when the deliberate interference destructively impacts a part of the RCS working band. Dependence of the bit error probability on the signal-to-noise ratio is calculated for the joint use of frequency division of information subsymbols and noise combating codes. It is shown that due to effective use of the frequency-energy resource of a radio line, considering the use of correction codes, a quite high noise immunity of RCS under the influence of deliberate interference can be assured. The indicated dependences of the error probability on the signal-to-noise ratio confirm that the reliability of data transmission can be significantly increased by the proper combination of signal spectrum spreading, applying of correction codes, and frequency division of subsymbols followed by their weight processing.

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Sârbu, Annamaria, Marius Sârbu, and Cosmin Șumălan. "Non Wi-Fi Devices Interference Testing in a 2.4 GHz Wi-Fi Home." Land Forces Academy Review 23, no. 2 (June 1, 2018): 143–50. http://dx.doi.org/10.2478/raft-2018-0017.

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Abstract Operating in probably the most crowded radio frequency bandwidth, the 2.4 GHz Wi-Fi is still common in the majority of living environments. Besides having to face problems regarding co-channel and adjacent channel influence, Wi-Fi often coexists with other radio technologies operating in this bandwidth which makes it ideal for interference testing. In this article authors propose the use of freely available mobile applications to measure Wi-Fi signal spreading within a residential home as well as to quantify Wi-Fi performance in the presence of some commonly available interferers. A complete analysis of spectrum use is also provided by using a spectrum analyzer. We have found that Wi-Fi throughput degradation due to Bluetooth technology operated in the immediate vicinity of a mobile client is on average 26,5 % and decreases with distance from the Wi-Fi client. The presence of an active video baby monitor leads to a 7,5 % throughput degradation, but its functionality in heavy Wi-Fi traffic environment is however limited. The use of spectrograms in interference analysis is essential for a better understanding of the measured results.

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Kumar, Shanigarapu, and Kalagadda Bikshalu. "FPGA Implementation of Adaptive Absolute SCORE Algorithm for Cognitive Radio Spectrum Sensing with WTM and LFA." International Journal of Intelligent Engineering and Systems 14, no. 1 (February 28, 2021): 1–11. http://dx.doi.org/10.22266/ijies2021.0228.01.

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Cognitive Radio (CR) is generally a wireless communication system that has the ability to improve the network’s system-capacity. Since, the white space or temporally unused spectrum are used to enhance the systemcapacity and the important operation involved in the cognition cycle is spectrum sensing. This spectrum sensing supports the Cognitive Radio users to adjust with the environment by identifying the white/vacant spaces without creating any interference to the primary user communication. The traditional filters such as Finite Impulse Response (FIR) filters and median filters used in the spectrum sensing obtains high area utilization in Cognitive Radio. In order to overcome this, an Adaptive Absolute SCORE (AAS) technique is developed based on the FIR for improving the sensing function and radio sensitivity. The area and frequency of the AAS are enhanced by using the Wallace tree multiplier (WTM) and Ladner-Fischer Adder (LFA) in the design of the FIR. The proposed architecture used for the spectrum sensing is named as AAS-WTM-LFA. This AAS-WTM-LFA architecture is developed in the Xilinx tool for different Virtex devices. The performance of AAS-WTM-LFA is analyzed in terms of LUT, slices, flip flops, bonded Input and Output Block (IOB), frequency and power. Additionally, the quality of signal processed through the AAS-WTM-LFA architecture is analyzed as Bit Error Rate (BER) and False Acceptance Rate (FAR). Additionally, the AAS-WTM-LFA architecture is compared with ACS, AAS, AAS-CSLA, AAS-R8-CSA and AASR8-CSLA. The number of LUT for AAS-WTM-LFA architecture is 247 for Spartan 6 device, that is less when compared to the remaining architectures.

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Journal articles on the topic 'Radio frequency spectrum analyzer'

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