Journal articles: 'Radar – Research'

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Chen, Duo, Ying Li, Yi Wen Wang, and Jin Xu. "Research on Marine Radar Image Collection Technology Based on OpenCV." Advanced Materials Research 798-799 (September 2013): 578–81. http://dx.doi.org/10.4028/www.scientific.net/amr.798-799.578.

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Marine radar image collection technology has been applied in many fileds. It has been a research focus at home and abroad for a long time. This paper proposes an architecture of marine radar image collection system based on Sperry radar, HPX Rader Information Board, OpenCV, SPX Function Library. And implementation of key technologies was diccussed from three aspects, includ-ing radar image display, collection and clear functions. This system has worked well in practice.

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Bluestein, Howard B., Robert M. Rauber, Donald W. Burgess, Bruce Albrecht, Scott M. Ellis, Yvette P. Richardson, David P. Jorgensen, et al. "Radar in Atmospheric Sciences and Related Research: Current Systems, Emerging Technology, and Future Needs." Bulletin of the American Meteorological Society 95, no. 12 (December 1, 2014): 1850–61. http://dx.doi.org/10.1175/bams-d-13-00079.1.

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To assist the National Science Foundation in meeting the needs of the community of scientists by providing them with the instrumentation and platforms necessary to conduct their research successfully, a meeting was held in late November 2012 with the purpose of defining the problems of the next generation that will require radar technologies and determining the suite of radars best suited to help solve these problems. This paper summarizes the outcome of the meeting: (i) Radars currently in use in the atmospheric sciences and in related research are reviewed. (ii) New and emerging radar technologies are described. (iii) Future needs and opportunities for radar support of high-priority research are discussed. The current radar technologies considered critical to answering the key and emerging scientific questions are examined. The emerging radar technologies that will be most helpful in answering the key scientific questions are identified. Finally, gaps in existing radar observing technologies are listed.

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Liang, Guan Hui, Gui Zhou Lv, and Li Dong Wang. "Data Fusion Algorithm Research Based on Multi Scout Radar Networking." Advanced Materials Research 933 (May 2014): 554–59. http://dx.doi.org/10.4028/www.scientific.net/amr.933.554.

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Considering the shortcoming of low measurement precision of single scout radar in battlefield, this paper advances the scheme of multi scout radar networking. Aiming at the core problem of networking data fusion of multi scout radars, this paper conducts research and advances data fusion algorithm based on polar coordinate system. This paper provides the realization flow of data fusion algorithm and pays more attention to the problem of coordinate conversion, error calculation, weight determination and data synthesis based on weight, and advances solution. Finally, taking five radars networking for example, conducts simulation experiment and result analysis, and the results shows that whether the fusion precision of distance data or the azimuth data all has greater improvement than measurement data.

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Gourley, Jonathan J., David P. Jorgensen, Sergey Y. Matrosov, and Zachary L. Flamig. "Evaluation of Incremental Improvements to Quantitative Precipitation Estimates in Complex Terrain." Journal of Hydrometeorology 10, no. 6 (December 1, 2009): 1507–20. http://dx.doi.org/10.1175/2009jhm1125.1.

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Abstract Advanced remote sensing and in situ observing systems employed during the Hydrometeorological Testbed experiment on the American River basin near Sacramento, California, provided a unique opportunity to evaluate correction procedures applied to gap-filling, experimental radar precipitation products in complex terrain. The evaluation highlighted improvements in hourly radar rainfall estimation due to optimizing the parameters in the reflectivity-to-rainfall (Z–R) relation, correcting for the range dependence in estimating R due to the vertical variability in Z in snow and melting-layer regions, and improving low-altitude radar coverage by merging rainfall estimates from two research radars operating at different frequencies and polarization states. This evaluation revealed that although the rainfall product from research radars provided the smallest bias relative to gauge estimates, in terms of the root-mean-square error (with the bias removed) and Pearson correlation coefficient it did not outperform the product from a nearby operational radar that used optimized Z–R relations and was corrected for range dependence. This result was attributed to better low-altitude radar coverage with the operational radar over the upper part of the basin. In these regions, the data from the X-band research radar were not available and the C-band research radar was forced to use higher-elevation angles as a result of nearby terrain and tree blockages, which yielded greater uncertainty in surface rainfall estimates. This study highlights the challenges in siting experimental radars in complex terrain. Last, the corrections developed for research radar products were adapted and applied to an operational radar, thus providing a simple transfer of research findings to operational rainfall products yielding significantly improved skill.

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Cockcroft, J. D. "Memories of radar research." IEE Proceedings A Physical Science, Measurement and Instrumentation, Management and Education, Reviews 132, no. 6 (1985): 327. http://dx.doi.org/10.1049/ip-a-1.1985.0069.

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Liu, Ying, Dian Ren Chen, and Lei Chen. "Research on Radar Target Simulator." Advanced Materials Research 971-973 (June 2014): 1726–29. http://dx.doi.org/10.4028/www.scientific.net/amr.971-973.1726.

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A radar target simulation system based on DRFM is designed in this paper ,in this system, the radar signal that is amplified and conversioned by the receive analog circuits is directly sampled by the ADC of DRFM, then the sampled data is stored in QDR2 SRAM array. When need to generate radar target simulation signal, the radar signal data is read from the QDR2 SRAM array and synthesis radar target simulation signal with the target characteristic parameters provided by the host computer. It can be widely used in various radar simulator occasions.

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Protat, Alain, Valentin Louf, Joshua Soderholm, Jordan Brook, and William Ponsonby. "Three-way calibration checks using ground-based, ship-based, and spaceborne radars." Atmospheric Measurement Techniques 15, no. 4 (February 21, 2022): 915–26. http://dx.doi.org/10.5194/amt-15-915-2022.

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Abstract. This study uses ship-based weather radar observations collected from research vessel Investigator to evaluate the Australian weather radar network calibration monitoring technique that uses spaceborne radar observations from the NASA Global Precipitation Mission (GPM). Quantitative operational applications such as rainfall and hail nowcasting require a calibration accuracy of ±1 dB for radars of the Australian network covering capital cities. Seven ground-based radars along the western coast of Australia and the ship-based OceanPOL radar are first calibrated independently using GPM radar overpasses over a 3-month period. The calibration difference between the OceanPOL radar (used as a moving reference for the second step of the study) and each of the seven operational radars is then estimated using collocated, gridded, radar observations to quantify the accuracy of the GPM technique. For all seven radars the calibration difference with the ship radar lies within ±0.5 dB, therefore fulfilling the 1 dB requirement. This result validates the concept of using the GPM spaceborne radar observations to calibrate national weather radar networks (provided that the spaceborne radar maintains a high calibration accuracy). The analysis of the day-to-day and hourly variability of calibration differences between the OceanPOL and Darwin (Berrimah) radars also demonstrates that quantitative comparisons of gridded radar observations can accurately track daily and hourly calibration differences between pairs of operational radars with overlapping coverage (daily and hourly standard deviations of ∼ 0.3 and ∼ 1 dB, respectively).

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Zhang, Yu, and Jun Wang. "Research and Realization of Phased Array Radar Functional Simulation System." Applied Mechanics and Materials 513-517 (February 2014): 2954–58. http://dx.doi.org/10.4028/www.scientific.net/amm.513-517.2954.

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In order to diminish the simulation granularity of phased array radar simulation system, modeling the target track is really necessary. This paper adds the target track simulation module and coordinate conversion module to the original functional simulation system of the phased array radar, thereby presents the frame construction, additional mathematical modules and simulate procedure of the improved simulation system. The phased array radars functional simulation system is proposed for the realization of the actual simulation software system. The simulation result verifies the efficiency of modeling method and mathematical modules.

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Matrosov, Sergey Y. "Ice Hydrometeor Shape Estimations Using Polarimetric Operational and Research Radar Measurements." Atmosphere 11, no. 1 (January 14, 2020): 97. http://dx.doi.org/10.3390/atmos11010097.

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A polarimetric radar method to estimate mean shapes of ice hydrometeors was applied to several snowfall and ice cloud events observed by operational and research weather radars. The hydrometeor shape information is described in terms of their aspect ratios, r, which represent the ratio of particle minor and major dimensions. The method is based on the relations between depolarization ratio (DR) estimates and aspect ratios. DR values, which are a proxy for circular depolarization ratio, were reconstructed from radar variables of reflectivity factor, Ze, differential reflectivity, ZDR, and copolar correlation coefficient ρhv, which are available from radar systems operating in either simultaneous or alternate transmutation of horizontally and vertically polarized signals. DR-r relations were developed for retrieving aspect ratios and their sensitivity to different assumptions and model uncertainties were discussed. To account for changing particle bulk density, which is a major contributor to the retrieval uncertainty, an approach is suggested to tune the DR-r relations using reflectivity-based estimates of characteristic hydrometeor size. The analyzed events include moderate snowfall observed by an operational S-band weather radar and a precipitating ice cloud observed by a scanning Ka-band cloud radar at an Arctic location. Uncertainties of the retrievals are discussed.

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Martin, William J., and Alan Shapiro. "Discrimination of Bird and Insect Radar Echoes in Clear Air Using High-Resolution Radars." Journal of Atmospheric and Oceanic Technology 24, no. 7 (July 1, 2007): 1215–30. http://dx.doi.org/10.1175/jtech2038.1.

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Abstract The source of clear-air reflectivity from operational and research meteorological radars has been a subject of much debate and study over the entire history of radar meteorology. Recent studies have suggested that bird migrations routinely contaminate wind profiles obtained at night, while historical studies have suggested insects as the main source of such nocturnal clear-air echoes. This study analyzes two cases of nocturnal clear-air return using data from operational Weather Surveillance Radar-1988 Doppler (WSR-88D) and X- and W-band research radars. The research radars have sufficient resolution to resolve the echo as point targets in some cases. By examining the radar cross section of the resolved point targets, and by determining the target density, it is found for both cases of nocturnal clear-air echoes that the targets are almost certainly insects. The analysis of the dependence of the echo strength on radar wavelength also supports this conclusion.

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Frech, Michael, Cornelius Hald, Maximilian Schaper, Bertram Lange, and Benjamin Rohrdantz. "Assessing and mitigating the radar–radar interference in the German C-band weather radar network." Atmospheric Measurement Techniques 16, no. 2 (January 20, 2023): 295–309. http://dx.doi.org/10.5194/amt-16-295-2023.

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Abstract. The national German weather radar network operates in C-band between 5.6 and 5.65 GHz. In a radar network, individual transmit frequencies have to be chosen such that radar–radar-induced interferences are avoided. In a unique experiment the Hohenpeißenberg research radar and five operational systems from the radar network were used to characterize radar–radar-induced interferences as a function of the radar frequency. The results allow assessment of the possibility of adding additional C-band radars with magnetron transmitters into the existing network. Based on the experiment, at least a 15 MHz separation of the nominal radar frequency is needed to avoid a radar–radar interference. The most efficient mitigation of radar–radar interference is achieved by the “Radar Tango”, which refers to the synchronized scanning of all radar systems in the network. Based on those results, additional C-band radar systems can be added to the German weather radar network if a further improvement of the radar coverage is needed.

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Isom, Bradley, Robert Palmer, Redmond Kelley, John Meier, David Bodine, Mark Yeary, Boon-Leng Cheong, Yan Zhang, Tian-You Yu, and Michael I. Biggerstaff. "The Atmospheric Imaging Radar: Simultaneous Volumetric Observations Using a Phased Array Weather Radar." Journal of Atmospheric and Oceanic Technology 30, no. 4 (April 1, 2013): 655–75. http://dx.doi.org/10.1175/jtech-d-12-00063.1.

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Abstract Mobile weather radars often utilize rapid-scan strategies when collecting observations of severe weather. Various techniques have been used to improve volume update times, including the use of agile and multibeam radars. Imaging radars, similar in some respects to phased arrays, steer the radar beam in software, thus requiring no physical motion. In contrast to phased arrays, imaging radars gather data for an entire volume simultaneously within the field of view (FOV) of the radar, which is defined by a broad transmit beam. As a result, imaging radars provide update rates significantly exceeding those of existing mobile radars, including phased arrays. The Advanced Radar Research Center (ARRC) at the University of Oklahoma (OU) is engaged in the design, construction, and testing of a mobile imaging weather radar system called the atmospheric imaging radar (AIR). Initial tests performed with the AIR demonstrate the benefits and versatility of utilizing beamforming techniques to achieve high spatial and temporal resolution. Specifically, point target analysis was performed using several digital beamforming techniques. Adaptive algorithms allow for improved resolution and clutter rejection when compared to traditional techniques. Additional experiments were conducted during two severe weather events in Oklahoma. Several digital beamforming methods were tested and analyzed, producing unique, simultaneous multibeam measurements using the AIR.

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Zhang, Ming Yang, Li Dai, and Cong Liu. "Development and Research Status of Marine Radar." Advanced Materials Research 912-914 (April 2014): 1242–44. http://dx.doi.org/10.4028/www.scientific.net/amr.912-914.1242.

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The Marine radar is essential electronic equipment for ship. Its performance is directly related to ship safety. By applying a variety of new systems and new technology, Reliability of radar equipments has been effectively improved. Marine radar will gradually develop into solid-state radar with multiple frequencies. At the same time, this paper also introduces the working principle and structure of solid-state radar.

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Худов, Г. В., Сальман Рашід Оваід, В. М. Ліщенко, and В. О. Тютюнник. "Methods of signal processing in a multiradar system of the same type of two-coordinated surveillance radars." Системи обробки інформації, no. 3(162), (September 30, 2020): 65–72. http://dx.doi.org/10.30748/soi.2020.162.07.

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The subject of research in the paper is the problem of developing methods of signal processing in a multiradar system of the same type of two-coordinate surveillance radars with mechanical rotation. The aim of the paper is to improve the quality of detection of air objects by combining the same type of two-coordinate radars in a multi-radar system. It is proposed to combine the existing surveillance radar stations into a spatially spaced coherent multi-radar system. The synthesis of optimal detectors of coherent and incoherent signals is carried out. The characteristics of detection of air objects in a multi-radar system with compatible signal receiving have been evaluated. The obtained results: the addition of the second radar, regardless of the degree of signal coherence, showed the greatest efficiency in the gain in terms of signal / noise, the optimal number of radars in the multi-radar system is not more than four. The expected signal / noise threshold gain in a system of four radars can be up to eighteen decibels for a system with coherent signals and up to eleven decibels for a system with incoherent signals. The using of more than four radars is impractical.

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叶, 英. "Transient Electromagnetic Structure Radar Research." Advances in Geosciences 09, no. 04 (2019): 218–29. http://dx.doi.org/10.12677/ag.2019.94025.

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16

Moore, Stephen. "UK airborne AESA radar research." IEEE Aerospace and Electronic Systems Magazine 25, no. 2 (February 2010): 29–35. http://dx.doi.org/10.1109/maes.2010.5442174.

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Ilcev, Dimov Stojce. "The development of maritime radar. Part 1: Before the Second World War." International Journal of Maritime History 32, no. 4 (November 2020): 996–1007. http://dx.doi.org/10.1177/0843871420977963.

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This research note identifies the precursors for development of shipborne radar for commercial and military applications. It comprises three main sections: first, the evolution of radar starting from the first practical demonstrations provided by Russian professor Aleksandar Stepanovich Popov in 1897; second, the invention of radar in eight nations; and third, early experiments with shipborne radars up to 1939.

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Chi, Jian Jun, Xiao Ming Luo, Xue Mei Han, and Bian Wen Wang. "Study on Simulation & Evaluation of Radar Network Operation Capability in Complex Electromagnetic Environment." Advanced Materials Research 591-593 (November 2012): 862–66. http://dx.doi.org/10.4028/www.scientific.net/amr.591-593.862.

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For research the radar network operation capability which are effected by complex electromagnetic environment, the paper modeling the radar operation capability cloud rules arithmetic in complex electromagnetic environment and radar network operation capability evaluation model. The operation capability of radar network, which are constituted by 3 radars in complex electromagnetic environment, is simulated & evaluated by Netlogo 3D. The result show that the operation capability of radar is impacted remarkably by complex electromagnetic environment, it could improve the operation capability availably by take the network mode.

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Ivanov Spassov, Sevdalin. "CHIRP FILTER JAMMING IMMUNITY RESEARCH." International Journal of Advanced Research 9, no. 01 (January 31, 2021): 966–71. http://dx.doi.org/10.21474/ijar01/12377.

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The pulse compression technique uses a matched filter to extract an echo signal in the radars receiver. A model of a matched filter for a chirp signal was synthesized using the Simulink Tool of the MATLAB software. Pulse jamming and chirp jamming signals were feed to the input of the matched filter. The output signals were measured. The matched filters degree of suppression of these jamming signals was assessed. Conclusions were made about the jamming immunity of a radar operating with a Chirp matched filter.

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Junyent, Francesc, and V. Chandrasekar. "Theory and Characterization of Weather Radar Networks." Journal of Atmospheric and Oceanic Technology 26, no. 3 (March 1, 2009): 474–91. http://dx.doi.org/10.1175/2008jtecha1099.1.

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Abstract A dense weather radar network is an emerging concept advanced by the Engineering Research Center for Collaborative Adaptive Sensing of the Atmosphere (CASA). In a weather radar environment, the specific radar units employed and the network topology will influence the characteristics of the data obtained. To define this, a general framework is developed to describe the radar network space, and formulations are obtained that can be used for weather radar network characterization. The models developed are useful for quantifying and comparing the performance of different weather radar networks. Starting with system characteristics that are used to specify individual radars, a theoretical basis is developed to extend the concept to network configurations of interest. A general network elemental cell is defined and employed as the parameterized domain over which different coverage aspects (such as detection sensitivity, beam size, and minimum beam height) are studied using analytical tools developed in the paper. Other important parameters are the number of different radars with overlapping coverage at a given point in the network domain and the coverage area and number of radars of a network and its elemental cells. A combination of analytical and numerically derived expressions is employed to obtain these parameters for several configurations. The radar network characterization tools developed are applied to the comparison of individual radar and networked radar configurations of interest. The values used in the calculations illustrate the CASA Integrated Project 1 (IP1) radar network and are compared to other radar systems.

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Ahmed, Shahzad, Karam Dad Kallu, Sarfaraz Ahmed, and Sung Ho Cho. "Hand Gestures Recognition Using Radar Sensors for Human-Computer-Interaction: A Review." Remote Sensing 13, no. 3 (February 2, 2021): 527. http://dx.doi.org/10.3390/rs13030527.

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Human–Computer Interfaces (HCI) deals with the study of interface between humans and computers. The use of radar and other RF sensors to develop HCI based on Hand Gesture Recognition (HGR) has gained increasing attention over the past decade. Today, devices have built-in radars for recognizing and categorizing hand movements. In this article, we present the first ever review related to HGR using radar sensors. We review the available techniques for multi-domain hand gestures data representation for different signal processing and deep-learning-based HGR algorithms. We classify the radars used for HGR as pulsed and continuous-wave radars, and both the hardware and the algorithmic details of each category is presented in detail. Quantitative and qualitative analysis of ongoing trends related to radar-based HCI, and available radar hardware and algorithms is also presented. At the end, developed devices and applications based on gesture-recognition through radar are discussed. Limitations, future aspects and research directions related to this field are also discussed.

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Wang, Fang, and Zhi Gang Wang. "Research on Detection Performance of a Composite Bistatic Radars System." Applied Mechanics and Materials 401-403 (September 2013): 1095–101. http://dx.doi.org/10.4028/www.scientific.net/amm.401-403.1095.

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A composite bistatic radars system is put forward to availably enhance the performance of anti-stealthy ,anti-reconnaissance, anti-jamming and anti-destruction for monostatic radar. The process modeling and technical project is introduced in this paper, and the detection area and measurement accuracy of the composite bistatic radars system is analyzed on the T/R-R process modeling. Lastly, a set of simulated experiments for the detection performance of composite bistatic radars system is carried out. The result of the simulation can provide the basis for structure multi-input and multi-output scouting early-warning detection system in the complex electromagnetic environment.

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Greenwald, Raymond A. "History of the Super Dual Auroral Radar Network (SuperDARN)-I: pre-SuperDARN developments in high frequency radar technology for ionospheric research and selected scientific results." History of Geo- and Space Sciences 12, no. 1 (May 11, 2021): 77–93. http://dx.doi.org/10.5194/hgss-12-77-2021.

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Abstract. Part I of this history describes the motivations for developing radars in the high frequency (HF) band to study plasma density irregularities in the F region of the auroral zone and polar cap ionospheres. French and Swedish scientists were the first to use HF frequencies to study the Doppler velocities of HF radar backscatter from F-region plasma density irregularities over northern Sweden. These observations encouraged the author of this paper to pursue similar measurements over northeastern Alaska, and this eventually led to the construction of a large HF-phased-array radar at Goose Bay, Labrador, Canada. This radar utilized frequencies from 8–20 MHz and could be electronically steered over 16 beam directions, covering a 52∘ azimuth sector. Subsequently, similar radars were constructed at Schefferville, Quebec, and Halley Station, Antarctica. Observations with these radars showed that F-region backscatter often exhibited Doppler velocities that were significantly above and below the ion-acoustic velocity. This distinguished HF Doppler measurements from prior measurements of E-region irregularities that were obtained with radars operating at very high frequency (VHF) and ultra-high frequency (UHF). Results obtained with these early HF radars are also presented. They include comparisons of Doppler velocities observed with HF radars and incoherent scatter radars, comparisons of plasma convection patterns observed simultaneously in conjugate hemispheres, and the response of these patterns to changes in the interplanetary magnetic field, transient velocity enhancements in the dayside cusp, preferred frequencies for geomagnetic pulsations, and observations of medium-scale atmospheric gravity waves with HF radars.

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Mahmood, Dalia A. "Estimation of Dual Polarization Weather Radar Variables." Al-Mustansiriyah Journal of Science 28, no. 2 (April 11, 2018): 1. http://dx.doi.org/10.23851/mjs.v28i2.492.

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Dual polarization weather radar has now become a widely used as instrument in meteorological offices around the world because of its capability in distinguishing different precipitation type and in improving the accuracy of quantitative precipitation estimation. The aim of this work is to estimate the polarimetry radar variables for radars of different frequency bands and study their behavior with rainfall rates. Calculations of polarimetry radar variables were made on the basis of several assumptions. The results showed that factors at horizontal and vertical polarization, ZH,V, ranges between 20 dBz respectively, and more than 55 dBz for light rain and extreme heavy rain respectively, and radar reflectivity factor at horizontal ZH is greater than radar reflectivity factor at vertical ZV for all rainfall rates. The differential reflectivity, ZDR, also increases with increasing rainfall rates since it is the difference between ZH and Zv. Calculations of specific differential attenuation indicated that X band radars are seriously atten-uated by rain and C band radars are less affected by rain. The specific differential attenuation, S band radars is very small. In addition to this feature, the results showed that the differential phase shift between return signals of horizontal and vertical polarizations for S band radars is much less than those for C and X band radars, and also, the results showed that the co-polarization correlation coefficient for S band the radars is much higher than those of C and X bands. In order to investigate the accuracy of the calculated polarimetric weather radar variables per-formed in this research, real radar measurements were used for this purpose. Results indicated that the range of values for calculated polarimetric radar variables are very consistent with range of values for measured variables

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Zhang, Ping Chuan, Li Min Hou, and Bu Yin Li. "Wave Arrival Direction Estimation Adaptive Antenna Array with Music Algorithms." Advanced Materials Research 179-180 (January 2011): 1342–45. http://dx.doi.org/10.4028/www.scientific.net/amr.179-180.1342.

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Passive radar based on GSM is a hot research field of new illuminators passive radars, and the wave arrival direction estimation is the key problem for detecting target. This paper designed adaptive antenna array for the GSM passive radar system, and give the complete Matlab simulation to verify the execution of the schedule, meanwhile, the result shows that the MUSIC algorithms is high accurate in the wave arrival direction compared with the Capon. All of this made a useful contribution to the research and application of the GSM-based passive radar.

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Weber, Christoph, Johannes von Eichel-Streiber, Jesús Rodrigo-Comino, Jens Altenburg, and Thomas Udelhoven. "Automotive Radar in a UAV to Assess Earth Surface Processes and Land Responses." Sensors 20, no. 16 (August 10, 2020): 4463. http://dx.doi.org/10.3390/s20164463.

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The use of unmanned aerial vehicles (UAVs) in earth science research has drastically increased during the last decade. The reason being innumerable advantages to detecting and monitoring various environmental processes before and after certain events such as rain, wind, flood, etc. or to assess the current status of specific landforms such as gullies, rills, or ravines. The UAV equipped sensors are a key part to success. Besides commonly used sensors such as cameras, radar sensors are another possibility. They are less known for this application, but already well established in research. A vast number of research projects use professional radars, but they are expensive and difficult to handle. Therefore, the use of low-cost radar sensors is becoming more relevant. In this article, to make the usage of radar simpler and more efficient, we developed with automotive radar technology. We introduce basic radar techniques and present two radar sensors with their specifications. To record the radar data, we developed a system with an integrated camera and sensors. The weight of the whole system is about 315 g for the small radar and 450 g for the large one. The whole system was integrated into a UAV and test flights were performed. After that, several flights were carried out, to verify the system with both radar sensors. Thereby, the records provide an insight into the radar data. We demonstrated that the recording system works and the radar sensors are suitable for the usage in a UAV and future earth science research because of its autonomy, precision, and lightweight.

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Abdu, Fahad Jibrin, Yixiong Zhang, Maozhong Fu, Yuhan Li, and Zhenmiao Deng. "Application of Deep Learning on Millimeter-Wave Radar Signals: A Review." Sensors 21, no. 6 (March 10, 2021): 1951. http://dx.doi.org/10.3390/s21061951.

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The progress brought by the deep learning technology over the last decade has inspired many research domains, such as radar signal processing, speech and audio recognition, etc., to apply it to their respective problems. Most of the prominent deep learning models exploit data representations acquired with either Lidar or camera sensors, leaving automotive radars rarely used. This is despite the vital potential of radars in adverse weather conditions, as well as their ability to simultaneously measure an object’s range and radial velocity seamlessly. As radar signals have not been exploited very much so far, there is a lack of available benchmark data. However, recently, there has been a lot of interest in applying radar data as input to various deep learning algorithms, as more datasets are being provided. To this end, this paper presents a survey of various deep learning approaches processing radar signals to accomplish some significant tasks in an autonomous driving application, such as detection and classification. We have itemized the review based on different radar signal representations, as it is one of the critical aspects while using radar data with deep learning models. Furthermore, we give an extensive review of the recent deep learning-based multi-sensor fusion models exploiting radar signals and camera images for object detection tasks. We then provide a summary of the available datasets containing radar data. Finally, we discuss the gaps and important innovations in the reviewed papers and highlight some possible future research prospects.

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SALVATORE, J. R. "Radar Guns." JNCI Journal of the National Cancer Institute 85, no. 1 (January 6, 1993): 67–68. http://dx.doi.org/10.1093/jnci/85.1.67.

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Borisova, Nina. "The emergence of radar in different countries: comparative-historical analysis." Genesis: исторические исследования, no. 7 (July 2020): 51–73. http://dx.doi.org/10.25136/2409-868x.2020.7.33501.

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The subject of this research is the activity of participants of the first radar projects in the pioneer countries (Soviet Union, United States, Great Britain, Germany), aimed at creation of prototype models and improvement of technical characteristics of new equipment. The goal consists in determination of the role of Soviet works in the genesis of radar. The evolutionary process of creation of the first radars, unfolded in the prewar period (1930s), is viewed individually for each country, with identification of differences and similarities. At the time of joining the World War II, all countries were armed with dozens of radars of meter and decimeter wavelength ranges, which were not too distant and accurate. Invention of a powerful multi-resonant magnetron of centimeter wavelength range (" core " of the radar) became a revolutionary event, since the transition to the centimeter range was capable to improve the radar parameters for successful accomplishment of military operations. Special attention is given to the little-known events in the history of this invention. Comparative analysis of the origin of radar in different countries (including foreign research), which was carried out for the first time, proves that the unique construct of the Soviet multi-resonant magnetron Alekseev-Malyarov had a priority, and perhaps, copied by other countries. The research results consists in illustration of the origin of radar overall, and Soviet contribution to the world history of radar in particular. Popularization of national scientific and technological achievements by the mass media, museum and educational activities may become the sphere of application of the obtained knowledge.

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Li, Xinzhi, and Shengbo Dong. "Research on Efficient Reinforcement Learning for Adaptive Frequency-Agility Radar." Sensors 21, no. 23 (November 27, 2021): 7931. http://dx.doi.org/10.3390/s21237931.

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Modern radar jamming scenarios are complex and changeable. In order to improve the adaptability of frequency-agile radar under complex environmental conditions, reinforcement learning (RL) is introduced into the radar anti-jamming research. There are two aspects of the radar system that do not obey with the Markov decision process (MDP), which is the basic theory of RL: Firstly, the radar cannot confirm the interference rules of the jammer in advance, resulting in unclear environmental boundaries; secondly, the radar has frequency-agility characteristics, which does not meet the sequence change requirements of the MDP. As the existing RL algorithm is directly applied to the radar system, there would be problems, such as low sample utilization rate, poor computational efficiency and large error oscillation amplitude. In this paper, an adaptive frequency agile radar anti-jamming efficient RL model is proposed. First, a radar-jammer system model based on Markov game (MG) established, and the Nash equilibrium point determined and set as a dynamic environment boundary. Subsequently, the state and behavioral structure of RL model is improved to be suitable for processing frequency-agile data. Experiments that our proposal effectively the anti-jamming performance and efficiency of frequency-agile radar.

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Liu, Yi, Shufang Zhang, Jidong Suo, Tingting Yao, and Jingbo Zhang. "Research on Cognitive Marine Radar Based on LFM Waveform Control." Sensors 19, no. 9 (May 13, 2019): 2200. http://dx.doi.org/10.3390/s19092200.

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In this paper, the method of applying cognitive radar technology to marine radar is studied, and the cognitive marine radar structure and transmitted signal model with three control parameters are constructed. The selection method of waveform control parameters, which is based on the target spatial distribution and the reference target detection effect with the minimum emission energy as the criterion, is given. The transmission signal control selection method given in this paper can flexibly realize different emission signal groups of m × n × p groups by independently setting the values m, n and p of three control parameters. It does not require radar hardware circuit reconstruction to meet the radar waveform changes. This is more convenient for the technical realization of cognitive marine radar. According to the method of this paper, a cognitive marine radar test system was constructed. The experimental results show that the proposed radar could reduce the emission energy by 15.9 dB compared with the traditional fixed-parameter pulse compression marine radar under the experimental conditions.

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Zrnic, Dusan S., Valery M. Melnikov, and John K. Carter. "Calibrating Differential Reflectivity on the WSR-88D." Journal of Atmospheric and Oceanic Technology 23, no. 7 (July 1, 2006): 944–51. http://dx.doi.org/10.1175/jtech1893.1.

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Abstract A calibration procedure of differential reflectivity on the Weather Surveillance Radar-1988 Doppler (WSR-88D) is described. It has been tested on NOAA's modified WSR-88D research and development polarimetric radar and is directly applicable to radars that simultaneously transmit and receive waves having horizontal and vertical polarization.

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Ilcev, Dimov Stojce. "Introduction to Coastal HF Maritime Surveillance Radars." Polish Maritime Research 26, no. 3 (September 1, 2019): 153–62. http://dx.doi.org/10.2478/pomr-2019-0056.

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Abstract This paper presents the main technical characteristics and working performances of coastal maritime surveillance radars, such as low-power High-Frequency Surface Wave Radars (HFSWR) and Over the Horizon Radars (OTHR). These radars have demonstrated to be a cost-effective long-range early-warning sensor for ship detection and tracking in coastal waters, sea channels and passages. In this work, multi-target tracking and data fusion techniques are applied to live-recorded data from a network of oceanographic HFSWR stations installed in Jindalee Operational Radar Network (JORN), Wellen Radar (WERA) in Ligurian Sea (Mediterranean Sea), CODAR Ocean Sebsorsin and in the German Bight (North Sea). The coastal Imaging Sciences Research (ISR) HFSWR system, Multi-static ISR HF Radar, Ship Classification using Multi-Frequency HF Radar, Coastal HF radar surveillance of pirate boats and Different projects of coastal HF radars for vessels detecting are described. Ship reports from the Automatic Identification System (AIS), recorded from both coastal and satellite Land Earth Stations (LES) are exploited as ground truth information and a methodology is applied to classify the fused tracks and to estimate system performances. Experimental results for all above solutions are presented and discussed, together with an outline for future integration and infrastructures.

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Cluckie, I. D., R. J. Griffith, A. Lane, and K. A. Tilford. "Radar hydrometeorology using a vertically pointing radar." Hydrology and Earth System Sciences 4, no. 4 (December 31, 2000): 565–80. http://dx.doi.org/10.5194/hess-4-565-2000.

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Abstract. A Vertically Pointing Radar (VPR) has been commissioned and deployed at a number of sites in southern England, to investigate numerically spatial and temporal variations in the vertical reflectivity profile (Zvp); particularly those associated with the intersection by the radar beam of a melting layer – the bright band. Comparisons with data from other instrumentation, notably with the S-band research radar at Chilbolton, but also with disdrometer data and rainfall measurements from a number of sophisticated rain gauges, show that VPR scans of the atmosphere provide detailed and reliable quantitative measurements of the Zvp. Analysis of a three year archive of Zvp data for Manchester has shown a bright band to be present in over 80% of rainfall events, highlighting the extent of the problem of bright band errors in scanning weather radar data. The primary characteristics of the bright band such as the height and magnitude (in dBZ) of the top, bottom and peak are identified objectively from VPR Zvp data by an automatic bright band recognition algorithm. It is envisaged that this approach could form the basis of an objective, automatic real time correction procedure for scanning weather radars. Keywords: Vertically Pointing Radar, weather radar, hydrometeorology, bright-band, melting-layer, vertical radar reflectivity

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Duanyang, Shi, Lin Qiang, Hu Bing, and Yan Xinyu. "Research on Comprehensive Evaluation Method of Radar." Journal of Physics: Conference Series 2278, no. 1 (May 1, 2022): 012010. http://dx.doi.org/10.1088/1742-6596/2278/1/012010.

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Abstract Aiming at the difficult problem of radar equipment evaluation caused by complex structure and many influencing factors, a comprehensive evaluation method of radar is proposed. This paper starts with the concept, elements and steps of comprehensive evaluation, and introduces the process of comprehensive evaluation in detail. The types of index weighting methods and the historical process of evaluation methods at home and abroad are summarized. According to the practical working experience, the radar comprehensive evaluation index system is constructed, and combining the characteristics of subjective and objective weighting methods, the combined subjective and objective weighting model is designed. On the basis of analysing the results of various evaluation methods, a combination model of evaluation results is constructed. The radar equipment is evaluated according to the scoring data of experts on the supportability of radar equipment. The effectiveness of the method is verified by an example.

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Dolan, Brenda A., and Steven A. Rutledge. "An Integrated Display and Analysis Methodology for Multivariable Radar Data." Journal of Applied Meteorology and Climatology 46, no. 8 (August 1, 2007): 1196–213. http://dx.doi.org/10.1175/jam2524.1.

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Abstract Polarimetric Doppler radars provide valuable information about the kinematic and microphysical structure of storms. However, in-depth analysis using radar products, such as Doppler-derived wind vectors and hydrometeor identification, has been difficult to achieve in (near) real time, mainly because of the large volumes of data generated by these radars, lack of quick access to these data, and the challenge of applying quality-control measures in real time. This study focuses on modifying and automating several radar-analysis and quality-control algorithms currently used in postprocessing and merging the resulting data from several radars into an integrated analysis and display in (near) real time. Although the method was developed for a specific network of four Doppler radars: two Weather Surveillance Radar-1988 Doppler (WSR-88D) radars (KFTG and KCYS) and two Colorado State University (CSU) research radars [Pawnee and CSU–University of Chicago–Illinois State Water Survey (CSU–CHILL)], the software is easily adaptable to any radar platform or network of radars. The software includes code to synthesize radial velocities to obtain three-dimensional wind vectors and includes algorithms for automatic quality control of the raw polarimetric data, hydrometeor identification, and rainfall rate. The software was successfully tested during the summers of 2004 and 2005 at the CSU–CHILL radar facility, ingesting data from the four-radar network. The display software allows users the ability to view mosaics of reflectivity, wind vectors, and rain rates, to zoom in and out of radar features easily, to create vertical cross sections, to contour data, and to archive data in real time. Despite the lag time of approximately 10 min, the software proved invaluable for diagnosing areas of intense rainfall, hail, strong updrafts, and other features such as mesocyclones and convergence lines. A case study is presented to demonstrate the utility of the software.

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Wei, Sai Nan, Rui Zhou Li, Li Chen, and Ji Ming Yao. "Research of Fiber Radar Absorbing Materials." Advanced Materials Research 602-604 (December 2012): 835–38. http://dx.doi.org/10.4028/www.scientific.net/amr.602-604.835.

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Electromagnetic parameters and absorbing properties of fiber absorbents (carbon fiber, SiC fiber and polycrystalline iron fiber) were introduced. The influences of the arrangement, thickness and content of the fibers on radar absorbing property were summarized. New development directions of the fiber absorbents were also indicated.

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KATO, Susumu. "Middle atmosphere research and radar observation." Proceedings of the Japan Academy, Series B 81, no. 8 (2005): 306–20. http://dx.doi.org/10.2183/pjab.81.306.

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Wang Ruijun, 王瑞君, 王宏强 Wang Hongqiang, 庄钊文 Zhuang Zhaowen, 秦玉亮 Qin Yuliang, and 邓彬 Deng Bin. "Research Progress of Terahertz Radar Technology." Laser & Optoelectronics Progress 50, no. 4 (2013): 040001. http://dx.doi.org/10.3788/lop50.040001.

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叶, 英. "Research on Transient Electromagnetic Road Radar." Advances in Geosciences 09, no. 06 (2019): 529–41. http://dx.doi.org/10.12677/ag.2019.96057.

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Conyers, Lawrence B. "Ground-penetrating radar for anthropological research." Antiquity 84, no. 323 (March 1, 2010): 175–84. http://dx.doi.org/10.1017/s0003598x00099841.

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During its development years, geophysical survey has served field archaeology by defining possible sites underground, prior to excavation or preservation. Now we can see the art taking off as a research method in its own right. After summarising some recent research applications of magnetic mapping, the author gives us three case studies from USA and Jordan, where ground-penetrating radar (GPR) has produced new interpretations of prehistory and history. Since GPR can map in horizontal slices without damage, it opens up important heritage preservation options. In one case, excavation was discouraged on ethical grounds, in another it was inhibited by the presence of later monuments and in a third, an early agricultural site, the GPR actually saw more than the excavators. This presages a research tool of particular power.

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Yi, Yucheng, Xianrong Wan, Jianxin Yi, and Ke Wang. "Passive radar polarisation filtering technology research." Journal of Engineering 2019, no. 21 (November 1, 2019): 7390–92. http://dx.doi.org/10.1049/joe.2019.0629.

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Anonymous. "U.K. strategies for radar hydrometeorological research." Eos, Transactions American Geophysical Union 74, no. 40 (1993): 460. http://dx.doi.org/10.1029/93eo00545.

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Zheng, Zexin, Wei Li, and Kun Zou. "Airborne Radar Anti-Jamming Waveform Design Based on Deep Reinforcement Learning." Sensors 22, no. 22 (November 10, 2022): 8689. http://dx.doi.org/10.3390/s22228689.

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Airborne radars are susceptible to a large number of clutter, noise and variable jamming signals in the real environment, especially when faced with active main lobe jamming, as the waveform shortcut technology in the traditional regime can no longer meet the actual battlefield radar anti-jamming requirements. Therefore, it is necessary to study anti-main-lobe jamming techniques for airborne radars in complex environments to improve their battlefield survivability. In this paper, we propose an airborne radar waveform design method based on a deep reinforcement learning (DRL) algorithm under clutter and jamming conditions, after previous research on reinforcement-learning (RL)-based airborne radar anti-jamming waveform design methods that have improved the anti-jamming performance of airborne radars. The method uses a Markov decision process (MDP) to describe the complex operating environment of airborne radars, calculates the value of the radar anti-jamming waveform strategy under various jamming states using deep neural networks and designs the optimal anti-jamming waveform strategy for airborne radars based on the duelling double deep Q network (D3QN) algorithm. In addition, the method uses an iterative transformation method (ITM) to generate the time domain signals of the optimal waveform strategy. Simulation results show that the airborne radar waveform designed based on the deep reinforcement learning algorithm proposed in this paper improves the signal-to-jamming plus noise ratio (SJNR) by 2.08 dB and 3.03 dB, and target detection probability by 26.79% and 44.25%, respectively, compared with the waveform designed based on the reinforcement learning algorithm and the conventional linear frequency modulation (LFM) signal at a radar transmit power of 5 W. The airborne radar waveform design method proposed in this paper helps airborne radars to enhance anti-jamming performance in complex environments while further improving target detection performance.

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Yan, Jingye, Ailan Lan, Xiang Deng, Jiaojiao Zhang, Chi Wang, and Hongbin Qiu. "An agile high-frequency radar used for ionospheric research." Journal of Space Weather and Space Climate 11 (2021): 25. http://dx.doi.org/10.1051/swsc/2021010.

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The Super Dual Radar Network (SuperDARN) is an international high-frequency (HF) radar network used to study plasma convection in the upper atmosphere. An agile SuperDARN radar (AgileDARN radar) was deployed to join the network in Jiamusi, China. The AgileDARN radar is a digital phased array radar equipped with an field-programmable gate array (FPGA)-based digital processing unit (DPU). It can operate as a standard SuperDARN radar or a multiple-input-multiple-out (MIMO) radar. Each channel can be controlled and processed separately. Digital beam forming (DBF) is used to make beam steering flexible and beam switching fast. Multiple sub-beam forming for receiving can be implemented on FPGA or computer to improve position accuracy. Additionally, internal calibration and external calibration are carried out to improve the performance of beam forming. The internal calibration is a self-calibration without any external connections. Calibration signals are produced by the generators in DPU. The gain and phase of transmitters/receivers are read and compared to the based transmitter/receiver. Then the differences are recorded to compensate for the imbalances. During the external calibration, meteor trails are used as calibration sources to detect the imbalance between antennas (including cables). The imbalances are compensated in the same way as the internal calibration. By calibration, the amplitude and phase imbalances between channels are reduced significantly.

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Miccinesi, Lapo, Alessandra Beni, and Massimiliano Pieraccini. "UAS-Borne Radar for Remote Sensing: A Review." Electronics 11, no. 20 (October 15, 2022): 3324. http://dx.doi.org/10.3390/electronics11203324.

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Since the 1950s, radar sensors have been widely used for the monitoring of the earth’s surface. The current radars for remote sensing can be divided into two main categories: Space/aerial-borne and ground-based systems. The unmanned aerial system (UAS) could bridge the gap between these two technologies. Indeed, UAS-borne radars can perform long scans (up to 100/200 m) in a brief time (a few minutes). From the 2010s, the interest in UAS-borne radars has increased in the research community, and it has led to the development of some commercial equipment and more than 150 papers. This review aims to present a study on the state-of-the-art of UAS-borne radars and to outline the future potential of this technology. In this work, the scientific literature was categorized in terms of application, purpose of the paper, radar technology, and type of UAS. In addition, a brief review of the main national UAS regulations is presented. The review on the technological state-of-the-art shows that there is currently no standard in terms of radar technology, and that the multi-helicopter could be the most used UAS in the near future. Moreover, the UAS-borne radar can be used for several remote sensing applications: From landmine detection to smart agriculture, and from archeological survey to research and rescue applications. Finally, the UAS-borne radar appears to be a mature technology, which is almost ready for industrialization. The main developmental limit may be found in the flight regulation, which does not allow for many operations and imposes strict limits on the payload weight.

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Hirth, Brian D., John L. Schroeder, W. Scott Gunter, and Jerry G. Guynes. "Measuring a Utility-Scale Turbine Wake Using the TTUKa Mobile Research Radars." Journal of Atmospheric and Oceanic Technology 29, no. 6 (June 1, 2012): 765–71. http://dx.doi.org/10.1175/jtech-d-12-00039.1.

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Abstract Observations of the wake generated by a single utility-scale turbine and collected by the Texas Tech University Ka-band mobile research radars on 27 October 2011 are introduced. Remotely sensed turbine wake observations using lidar technology have proven effective; however, the presented radar capabilities provide a larger observational footprint and greater along-beam resolution than current scanning lidar systems. Plan-position indicator and range–height indicator scanning techniques are utilized to produce various wake analyses. Preliminary analyses confirm radial velocity and wind speed deficits immediately downwind of the turbine hub to be on the order of 50%. This introduction lays the groundwork for more in-depth analyses of wake structure and evolution using the Texas Tech University Ka-band radar systems, including wake meandering and wake-to-wake interaction in large wind park deployments.

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Ueng, Shyh-Kuang. "A Hybrid RCS Reduction Method for Wind Turbines." Energies 13, no. 19 (September 29, 2020): 5078. http://dx.doi.org/10.3390/en13195078.

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Wind turbine towers produce significant scatterings when illuminated by radars. Their reflectivity affects air traffic control, military surveillance, vessel tracking, and weather data sensing processes. Reducing the radar cross-section (RCS) of wind turbines is an essential task when building wind farms. It has been proved that round and bumpy structures can scatter radar waves and reduce the RCS of a reflector. Other research showed that taper towers generate smaller radar returns than cylindrical towers. In this research, we combine both strategies to devise a more effective method for designing wind turbine towers in the hope that their RCS can be further reduced. The test results reveal that the proposed method out-performs current reshaping methods. Wind turbine towers possessing taper shapes and periodic surface bumps deflect incident electromagnetic waves to insignificant directions. Thus, radar returns in the back-scattering directions decrease. Other experiments also verify that the proposed method maintains its effectiveness for radar waves with varying frequencies and polarization.

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Xu, Wei Dong, Fang Mo Shi, Jun Liu, and Yao Ma. "Preliminary Research on Deformable Member for Shape Stealth of Tank." Applied Mechanics and Materials 602-605 (August 2014): 2478–81. http://dx.doi.org/10.4028/www.scientific.net/amm.602-605.2478.

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In the modern battlefield, Radar is one of the most important equipment in the field of information access and precision-guided, battlefield targets face increasing radar threat, the application of radar stealth technology can improve the survivability of the target to some extent. But the development of radar stealth technology with tank for typical ground weapon is slow, especially to the existing ground weapon. This paper analyzes the distribution of radar scattering characteristics of the existing tank, and the deformable member for shape stealth for existing tank is designed, the results prove that the RCS of tank can be preferably reduced with the deformable members.

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Jorgensen, David P., Maiana N. Hanshaw, Kevin M. Schmidt, Jayme L. Laber, Dennis M. Staley, Jason W. Kean, and Pedro J. Restrepo. "Value of a Dual-Polarized Gap-Filling Radar in Support of Southern California Post-Fire Debris-Flow Warnings." Journal of Hydrometeorology 12, no. 6 (December 1, 2011): 1581–95. http://dx.doi.org/10.1175/jhm-d-11-05.1.

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Abstract A portable truck-mounted C-band Doppler weather radar was deployed to observe rainfall over the Station Fire burn area near Los Angeles, California, during the winter of 2009/10 to assist with debris-flow warning decisions. The deployments were a component of a joint NOAA–U.S. Geological Survey (USGS) research effort to improve definition of the rainfall conditions that trigger debris flows from steep topography within recent wildfire burn areas. A procedure was implemented to blend various dual-polarized estimators of precipitation (for radar observations taken below the freezing level) using threshold values for differential reflectivity and specific differential phase shift that improves the accuracy of the rainfall estimates over a specific burn area sited with terrestrial tipping-bucket rain gauges. The portable radar outperformed local Weather Surveillance Radar-1988 Doppler (WSR-88D) National Weather Service network radars in detecting rainfall capable of initiating post-fire runoff-generated debris flows. The network radars underestimated hourly precipitation totals by about 50%. Consistent with intensity–duration threshold curves determined from past debris-flow events in burned areas in Southern California, the portable radar-derived rainfall rates exceeded the empirical thresholds over a wider range of storm durations with a higher spatial resolution than local National Weather Service operational radars. Moreover, the truck-mounted C-band radar dual-polarimetric-derived estimates of rainfall intensity provided a better guide to the expected severity of debris-flow events, based on criteria derived from previous events using rain gauge data, than traditional radar-derived rainfall approaches using reflectivity–rainfall relationships for either the portable or operational network WSR-88D radars. Part of the reason for the improvement was due to siting the radar closer to the burn zone than the WSR-88Ds, but use of the dual-polarimetric variables improved the rainfall estimation by ~12% over the use of traditional Z–R relationships.

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Journal articles on the topic 'Radar – Research'

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