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A Dual-polarized Frequency Selective Rasorber with a Tunable Transparent Band
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作者 SHI Tongtong ZHANG Xiaofa +4 位作者 WU Weiwei WANG Shaozhi XU Yixuan YAN Yuchen YAN Xiao 《电讯技术》 北大核心 2024年第10期1569-1575,共7页
A tunable dual polarization absorption-transmission-absorption(A-T-A)frequency selective absorbers(FSR)to address the issue of high insertion loss in current tunable FSRs is proposed.The lumped resistors are loaded on... A tunable dual polarization absorption-transmission-absorption(A-T-A)frequency selective absorbers(FSR)to address the issue of high insertion loss in current tunable FSRs is proposed.The lumped resistors are loaded onto the lossy layer to absorb electromagnetic waves within the absorption band.The varactor diodes are loaded onto another lossless layer to control the transmission frequency band of the FSR.Its equivalent circuit model is provided.The proposed tunable FSR can change the passband within the range of 14.5~15.5 GHz by changing the bias voltage applied to the lossless transmission layer,while maintaining insertion loss above-1.67 dB.The series resonant structure of the lossy layer generates bilateral absorption bands between 10.2~13.5 GHz and 17.2~22 GHz,with broadband reflection suppression ranging from 10.3 GHz to 22 GHz(70.7%).The prototype is manufactured,and the measured results have verified the simulation results. 展开更多
关键词 tunable frequency selective rasorber dual-polarIZATION RCS reduction stealthy radomes
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Evaluating the Algorithm for Correction of the Bright Band Effects in QPEs with S-, C-and X-Band Dual-Polarized Radars 被引量:1
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作者 Yang CAO Debin SU +1 位作者 Xingang FAN Hongbin CHEN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2019年第1期41-54,共14页
The bright band, a layer of enhanced radar reflectivity associated with melting ice particles, is a major source of signifi- cant overestimation in quantitative precipitation estimation (QPE) based on the Z-R (refl... The bright band, a layer of enhanced radar reflectivity associated with melting ice particles, is a major source of signifi- cant overestimation in quantitative precipitation estimation (QPE) based on the Z-R (reflectivity factor-rain rate) relationship. The effects of the bright band on radar-based QPE can be eliminated by vertical profile of reflectivity (VPR) correction. In this study, we applied bright-band correction algorithms to evaluate three different bands (S-, C- and X-band) of dual-polarized radars and to reduce overestimation errors in Z-R relationship-based QPEs. After the reflectivity was corrected by the algo- rithms using average VPR (AVPR) alone and a combination of average VPR and the vertical profile of the copolar correlation coefficient (AVPR+CC), the QPEs were derived. The bright-band correction and resulting QPEs were evaluated in eight precipitation events by comparing to the uncorrected reflectivity and rain-gange observations, separately. The overestimation of Z-R relationship-based QPEs associated with the bright band was reduced after correction by the two schemes for which hourly rainfall was less than 5 mm. For the verification metrics of RMSE (root-mean-square error), RMAE (relative mean absolute error) and RMB (relative mean bias) of QPEs, averaged over all eight cases, the AVPR method improved from 2.28, 0.94 and 0.78 to 1.55, 0.60 and 0.40, respectively, while the AVPR+CC method improved to 1.44, 0.55 and 0.30, respectively. The QPEs after AVPR+CC correction had less overestimation than those after AVPR correction, and similar conclusions were drawn for all three different bands of dual-polarized radars. 展开更多
关键词 dual-polarized radar bright band QPE vertical profile of reflectivity
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Bandwidth-enhanced dual-polarized antenna with improved broadband integrated balun and distributed parasitic element
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作者 Fu Suidao Cao Zhenxin +2 位作者 Gao Di Chen Peng Xu Changzhi 《Journal of Southeast University(English Edition)》 EI CAS 2020年第4期367-375,共9页
A bandwidth-enhanced dual-polarized antenna is proposed for 2/3/4/5G applications,which is composed of distributed parasitic elements(DPEs),a main radiator,two improved broadband integrated baluns and a reflector.Firs... A bandwidth-enhanced dual-polarized antenna is proposed for 2/3/4/5G applications,which is composed of distributed parasitic elements(DPEs),a main radiator,two improved broadband integrated baluns and a reflector.First,a novel tooth-shape shorted slot line in the improved broadband integrated balun is analyzed to adjust the input impedance of the antenna.Then,DPEs with 2×2 circular plates loading over the main radiator are proposed to improve broadband impedance matching and radiation pattern.By utilizing impedance compensation of the tooth-shaped shorted slot line and the electromagnetic induction of the DPEs,the antenna achieves an enhanced impedance bandwidth and a stable radiation pattern.To verify these ideas,the bandwidth-enhanced dual-polarized antenna was fabricated and measured.The experimental results indicate that the proposed antenna achieves an operating bandwidth of 72.2%(1.69 to 3.60 GHz)with a return loss(RL)less than-15 dB and a port-to-port isolation(ISO)larger than 30 dB.The antenna obtains a half-power beamwidth(HPBW)within(66±5)°and a gain within(9.0±0.6)dBi in the 2/3/4G bands,and an HPBW within(61.5±2.5)°and a gain within(9.8±0.3)dBi in the 5G band.Across the whole band,the cross-polarization discrimination(XPD)and the front-to-back ratio are both larger than 20 dB. 展开更多
关键词 dual-polarized antenna bandwidth enhancement integrated balun distributed parasitic elements impedance matching
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An Efficient CSI Feedback Scheme for Dual-Polarized MIMO Systems Using Layered Multi-Paths Information
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作者 Feng Zheng Yijian Chen +1 位作者 Qian Zhan Jie Zhang 《China Communications》 SCIE CSCD 2017年第5期91-104,共14页
Massive MIMO is one of tile enabling technologies tbr beyond 4G and 5G systems due to its ability to provide beamforming gain and reduce interference Dual-polarized antenna is widely adopted to accommodate a large num... Massive MIMO is one of tile enabling technologies tbr beyond 4G and 5G systems due to its ability to provide beamforming gain and reduce interference Dual-polarized antenna is widely adopted to accommodate a large number of antenna elements in limited space. However, current CSI(channel state information) feedback schemes developed in LTE for conventional MIMO systems are not efficient enough for massive MIMO systems since the overhead increases almost linearly with the number of antenna. Moreover, the codebook for massive MIMO will be huge and difficult to design with the LTE methodology. This paper proposes a novel CSI feedback scheme named layered Multi-paths Information based CSI Feedback (LMPIF), which can achieve higher spectrum efficiency for dual-polarized antenna system with low feedback overhead. The MIMO channel is decomposed into long term components (multipath directions and amplitudes) and short term components (multipath phases). The relationship between the two components and the optimal precoder is derived in closed form. To reduce the overhead, different granularities in feedback time have been applied for the long term components and short term components Link and system level simulation results prove that LMPIF can improve performance considerably with low CSI feedback overhead. 展开更多
关键词 communication and information system: efficient CSI feedback: channel characteristie analysis dual-polarized massive MIMO: layered Multi-Paths information codeword model
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Diversity–Multiplexing Tradeoff and Outage Performance for 2&times;2 Dual-Polarized Uncorrelated Rice MIMO Channels
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作者 Yanping Huang Guangliang Ren 《Communications and Network》 2013年第3期319-326,共8页
In this paper, diversity-multiplexing tradeoff (DMT) curve for 2×2 Dual-Polarized uncorrelated Rice MIMO channels is studied. Exact expressions for statistic information of mutual information exponent are derived... In this paper, diversity-multiplexing tradeoff (DMT) curve for 2×2 Dual-Polarized uncorrelated Rice MIMO channels is studied. Exact expressions for statistic information of mutual information exponent are derived. Impacts of channel parameters such as signal to noise ratio (SNR), k-factor and cross polarization discrimination (XPD) on mutual information exponent are analyzed. Compared to conventional single-polarized (SP) Rice MIMO systems, a qualitatively different behavior is observed for DP Rice systems. The work in this paper, allows identifying quantitatively for which channels (k-factor) and SNR levels the use of dual polarization becomes beneficial. Gamma or lognormal distribution are used to describe mutual information component, and a theoretical formulation for finite-SNR DMT curve in 2×2 DP uncorrelated Rice channels is presented for the first time, which is valid in low and medium SNRs when multiplexing gain is larger than 0.75. 展开更多
关键词 DMT curve dual-polarized Uncorrelated RICE Channel Mutual Information EXPONENT K-FACTOR Outage Probablity Approximation
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Electromagnetic Band Gap Loaded Square Waveguide Band-Pass Filter for Dual-Polarized Application
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作者 Yi-Ming Tang 《Wireless Engineering and Technology》 2012年第4期210-213,共4页
An Electromagnetic Band Gap (EBG) loaded square waveguide Band-Pass Filter (BPF) is proposed in this paper. It’s simply composed by symmetrically loading periodical metal diaphragms on each wall of a square waveguide... An Electromagnetic Band Gap (EBG) loaded square waveguide Band-Pass Filter (BPF) is proposed in this paper. It’s simply composed by symmetrically loading periodical metal diaphragms on each wall of a square waveguide. The influences of insert sizes and loading periods on the overall BPF performances are analyzed. Experimental results agree well with those predicted. 6 GHz pass-band with insert loss less than 1 dB, 2.5 GHz stop-band and larger than 25 dB polarization isolation can be obtained. The BPF can be applied in dual-polarized waveguide-based antenna-feed systems. 展开更多
关键词 Electromagnetic Band Gap (EBG) BAND-PASS Filter (BPF) dual-polarized SQUARE Waveguide
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Dual-Polarized Slot-Coupled Microstrip Antenna with Very High Isolation 被引量:4
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作者 钟顺时 梁仙灵 汪伟 《Journal of Shanghai University(English Edition)》 CAS 2005年第4期336-338,共3页
A wideband dual-polarized slot-coupled stacked microstrip antenna with very high isolation and low cross-polarization is presented. To improve isolation between two poiarization ports, the stacked patches are excited ... A wideband dual-polarized slot-coupled stacked microstrip antenna with very high isolation and low cross-polarization is presented. To improve isolation between two poiarization ports, the stacked patches are excited by an open-ended and a T-shaped microstrip lines both via two H-shaped slots placed in a "T" configuration. The measured isolation is better than 40.5 dB over the bandwidth from 8.8 to 9.8 GHz with cross-polarization level less than - 28.5 dB. The measured VSWR ≤ 2 bandwidths reach 20.7 96 and 19.196 at the verrical and horizontal polarization ports, respectively. This antenna is suitable to be used as array elements in spacebome synthetic aperture radars (SAR) and active phased array radars. 展开更多
关键词 microstrip antenna dual-polarIZATION ISOLATION cross-polarization.
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Broadband printed antennas and dual-polarized microstrip and waveguide slot antenna arrays 被引量:1
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作者 汪伟 《Journal of Shanghai University(English Edition)》 CAS 2006年第3期282-282,共1页
In order to meet the urgent needs in wireless communications, microwave image synthetic aperture radars (SAR), and electronic warfare systems, this dissertation studies several types of broadband dual-polarized plan... In order to meet the urgent needs in wireless communications, microwave image synthetic aperture radars (SAR), and electronic warfare systems, this dissertation studies several types of broadband dual-polarized planar antenna elements and arrays, and proposes a few of novel designs with experimental verification. The main accomplishments reported in the dissertation are as follows. 展开更多
关键词 BROADBAND dual-polarIZATION MONOPOLE microstrip antenna waveguide slot antenna synthetic aperture radar(SAR).
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Wideband dual-polarized slot-coupled microstrip array for synthetic aperture radar application 被引量:1
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作者 梁仙灵 钟顺时 汪伟 《Journal of Shanghai University(English Edition)》 CAS 2007年第3期283-285,共3页
An 8 × 1-element wideband dual-polarized slot-coupled microstrip antenna array with high isolation and low crosspolarization in X-band is presented. The array antenna offers an impedance bandwidth (VSWR≤2) of ... An 8 × 1-element wideband dual-polarized slot-coupled microstrip antenna array with high isolation and low crosspolarization in X-band is presented. The array antenna offers an impedance bandwidth (VSWR≤2) of 23% and 21% for dual polarization ports, respectively. The measured isolation between two polarization ports is better than 35 dB and the measured cross-polarization level below -25 dB in the main beam over the operation frequency band of 9.35 GHz to 9.75 GHz. This array is well suitable for X-band SAR (synthetic aperture radar) antenna apphcation. 展开更多
关键词 microstrip antenna array dual-polarIZATION ISOLATION WIDEBAND
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Over-the-Air Testing for Dual-Polarized MIMO Devices: Setup Design and Validation
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作者 Yong Li Junli Li +1 位作者 Xiang Zhang Guiming Wei 《China Communications》 SCIE CSCD 2022年第11期268-281,共14页
Over-the-air(OTA)testing is considered as the only feasible solution to evaluate radio performances of the fifth-generation(5G)wireless devices which feature two important technologies,i.e.,massive multiple-input mult... Over-the-air(OTA)testing is considered as the only feasible solution to evaluate radio performances of the fifth-generation(5G)wireless devices which feature two important technologies,i.e.,massive multiple-input multiple-output(MIMO)and millimeter-wave(mmWave).The multi-probe anechoic chamber(MPAC)based OTA setup is able to emulate realistic multipath propagation conditions in a controlled manner.This paper investigates an MPAC OTA setup which is capable of evaluating the performances of 5G base stations as the devices-under-test(DUTs)which are equipped with dual-polarized antennas.Both end-to-end setup and probe configuration for the considered MPAC setup will be elaborated.Furthermore,since building a practical MPAC setup is expensive,time-consuming,and error-prone,an endto-end software testbed is established for validation purpose to avoid technical risks before finalizing an MPAC setup.The architecture of the testbed is presented,which can emulate both the channel profiles perceived by the DUT and the physical-layer behaviors of the considered link conforming to 5G new radio(NR)specifications.Results show that the performances under the emulated channel agree well with those under the target channel,validating the accuracy and effectiveness of the MPAC method. 展开更多
关键词 anechoic chamber dual-polarIZATION multi-probe anechoic chamber(MPAC) over-the-air(OTA) performance evaluation
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A Broadband45°Dual-Polarized Multiple-Input Multiple-Output Antenna for 5G Base Stations with Extra Decoupling Elements 被引量:2
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作者 Qi Wu Peiyu Liang Xiaoming Chen 《Journal of Communications and Information Networks》 2018年第1期31-37,共7页
A dual-polarized multiple-input multiple-output(MIMO)antenna is proposed for 5G base stations.Each antenna element consists of two orthogonally placed fan-shaped dipole elements and45°dual-polarized feed-ing str... A dual-polarized multiple-input multiple-output(MIMO)antenna is proposed for 5G base stations.Each antenna element consists of two orthogonally placed fan-shaped dipole elements and45°dual-polarized feed-ing structures are used to achieve broadband operation.The resonant frequency of the array element is from 3.3 to 4.2 GHz,which covers the mainstream spectrum allocations of 5G mobile networks.H-shaped coupling elements are used to improve the isolation between the neighboring antenna elements and the mutual coupling is reduced by over 4 dB.The envelope correlation of a 2×2 array is provided for verification. 展开更多
关键词 base station broad band dual-polarized 5th generation mobile networks MIMO antenna mutual coupling
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Design of broadband dual-polarized antenna with integrated Marchand balun
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作者 Hao Honggang He Yong +1 位作者 Ren Yi Liu Yanhui 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2015年第3期118-124,共7页
A design of broadband dual-polarized antenna with low cross polarization and high isolation was presented. The antenna is composed of a cross dipole, a folded ground, two feeding networks, and a reflector. The impedan... A design of broadband dual-polarized antenna with low cross polarization and high isolation was presented. The antenna is composed of a cross dipole, a folded ground, two feeding networks, and a reflector. The impedance bandwidth was enhanced by utilizing the mutual coupling between the two dipoles. A kind of meandering folded Marchand balun was skillfully integrated on the support column of the antenna to excite the dipole differentially, which can deliver both balanced (within 0.5 dB) power splitting and consistent (±5°) phase shifting from 1.71 GHz to 2.17 GHz. The standing wave ratios (SWRs) of each port are less than 1.5. By using this feeding network, the antenna has good performance in isolation (〉 45 dB) and cross polarization (〉 30 dB) over the entire operating frequency band. Moreover, the gain (-8.6 dB) of the proposed antenna is stable with frequency and the antenna structure is very firm due to the support column. The proposed antenna can be easily formed an array for digital cellular system (DCS), personal communications service (PCS) and 3rd generation (3G) applications. 展开更多
关键词 dual-polarized antenna cross dipole BALUN high isolation low cross polarization
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Recent Progress in Dual-Polarization Radar Research and Applications in China 被引量:18
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作者 Kun ZHAO Hao HUANG +11 位作者 Mingjun WANG Wen-Chau LEE Gang CHEN Long WEN Jing WEN Guifu ZHANG Ming XUE Zhengwei YANG Liping LIU Chong WU Zhiqun HU Sheng CHEN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2019年第9期961-974,共14页
Dual-polarization(dual-pol)radar can measure additional parameters that provide more microphysical information of precipitation systems than those provided by conventional Doppler radar.The dual-pol parameters have be... Dual-polarization(dual-pol)radar can measure additional parameters that provide more microphysical information of precipitation systems than those provided by conventional Doppler radar.The dual-pol parameters have been successfully utilized to investigate precipitation microphysics and improve radar quantitative precipitation estimation(QPE).The recent progress in dual-pol radar research and applications in China is summarized in four aspects.Firstly,the characteristics of several representative dual-pol radars are reviewed.Various approaches have been developed for radar data quality control,including calibration,attenuation correction,calculation of specific differential phase shift,and identification and removal of non-meteorological echoes.Using dual-pol radar measurements,the microphysical characteristics derived from raindrop size distribution retrieval,hydrometeor classification,and QPE is better understood in China.The limited number of studies in China that have sought to use dual-pol radar data to validate the microphysical parameterization and initialization of numerical models and assimilate dual-pol data into numerical models are summarized.The challenges of applying dual-pol data in numerical models and emerging technologies that may make significant impacts on the field of radar meteorology are discussed. 展开更多
关键词 dual-polarIZATION RADAR QUANTITATIVE PRECIPITATION estimation PRECIPITATION MICROPHYSICS DROP size distribution numerical model
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Reliability of X-band Dual-polarization Phased Array Radars Through Comparison with an S-band Dual-polarization Doppler Radar 被引量:2
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作者 ZHOU Xin-yu HU Dong-ming +2 位作者 ZHANG Yu LI Hao-wen TIAN Cong-cong 《Journal of Tropical Meteorology》 SCIE 2022年第2期218-236,共19页
Based on the observations of a squall line on 11 May 2020 and stratiform precipitation on 6 June 2020 from two X-band dual-polarization phased array weather radars(DP-PAWRs)and an S-band dual-polarization Doppler weat... Based on the observations of a squall line on 11 May 2020 and stratiform precipitation on 6 June 2020 from two X-band dual-polarization phased array weather radars(DP-PAWRs)and an S-band dual-polarization Doppler weather radar(CINRAD/SA-D),the data reliability of DP-PAWR and its ability to detect the fine structures of mesoscale weather systems were assessed.After location matching,the observations of DP-PAWR and CINRAD/SA-D were compared in terms of reflectivity(Z_(H)),radial velocity(V),differential reflectivity(Z_(DR)),and specific differential phase(K_(DP)).The results showed that:(1)DP-PAWR has better ability to detect mesoscale weather systems than CINRAD/SAD;the multi-elevation-angles scanning of the RHI mode enables DP-PAWR to obtain a wider detection range in the vertical direction.(2)DP-PAWR’s Z_(H)and V structures are acceptable,while its sensitivity is worse than that of CINRAD/SA-D.The Z H suffers from attenuation and the Z_(H)area distribution is distorted around strong rainfall regions.(3)DP-PAWR’s Z_(DR)is close to a normal distribution but slightly smaller than that of CINRAD/SA-D.The K_(DP)products of DP-PAWR have much higher sensitivity,showing a better indication of precipitation.(4)DP-PAWR is capable of revealing a detailed and complete structure of the evolution of the whole storm and the characteristics of particle phase variations during the process of triggering and enhancement of a small cell in the front of a squall line,as well as the merging of the cell with the squall line,which cannot be observed by CINRAD/SA-D.With its fast volume scan feature and dual-polarization detection capability,DP-PAWR shows great potential in further understanding the development and evolution mechanisms of meso-γ-scale and microscale weather systems. 展开更多
关键词 comparative observations mesoscale weather systems fine structure X-band dual-polarization phased array radar S-band dual-polarization Doppler radar
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Identification and Removal of Non-meteorological Echoes in Dual-polarization Radar Data Based on a Fuzzy Logic Algorithm 被引量:1
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作者 Bo-Young YE Gyu Won LEE Hong-Mok PARK 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2015年第9期1217-1230,共14页
A major issue in radar quantitative precipitation estimation is the contamination of radar echoes by non-meteorological targets such as ground clutter,chaff,clear air echoes etc.In this study,a fuzzy logic algorithm f... A major issue in radar quantitative precipitation estimation is the contamination of radar echoes by non-meteorological targets such as ground clutter,chaff,clear air echoes etc.In this study,a fuzzy logic algorithm for the identification of non-meteorological echoes is developed using optimized membership functions and weights for the dual-polarization radar located at Mount Sobaek.For selected precipitation and non-meteorological events,the characteristics of the precipitation and non-meteorological echo are derived by the probability density functions of five fuzzy parameters as functions of reflectivity values.The membership functions and weights are then determined by these density functions.Finally,the nonmeteorological echoes are identified by combining the membership functions and weights.The performance is qualitatively evaluated by long-term rain accumulation.The detection accuracy of the fuzzy logic algorithm is calculated using the probability of detection(POD),false alarm rate(FAR),and clutter–signal ratio(CSR).In addition,the issues in using filtered dual-polarization data are alleviated. 展开更多
关键词 dual-polarization radar non-meteorological echo quality control fuzzy logic algorithm
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Experimental Research of Dual-Polarization Passive Radar Based on DTTB Signal 被引量:1
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作者 Yonghu Zeng Xiaofeng Ai +2 位作者 Liandong Wang Xiaoyang Wang Guangyong Zheng 《Journal of Computer and Communications》 2016年第3期101-107,共7页
The passive radar is a hot research topic. A multi-channel wideband passive radar experimental system is designed and the digital television terrestrial broadcasting (DTTB) signal is chosen to carry out the target det... The passive radar is a hot research topic. A multi-channel wideband passive radar experimental system is designed and the digital television terrestrial broadcasting (DTTB) signal is chosen to carry out the target detection experiment of civil aviation aircraft. The polarization and spatial filtering methods are used to solve the strong direct path interference suppression problems brought by the receiving system location;combined with the characteristics of DTTB signal, the block length selection interval in the block batch processing method for range-Doppler images calculation is given;the clutter suppression performance is compared through the experimental data receiving from different bistatic polarization channels, the conclusion is different from the monostatic radar and it can guide the passive radar experiment. 展开更多
关键词 Passive Radar Clutter Suppression Block Batch Processing dual-polarIZATION
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An enhanced spectral diversity coregistration method for dualpolarimetric Sentinel-1A/B TOPS data
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作者 Nan Fang Xingjun Luo +5 位作者 Peng Shen Lei Xie Guoming Liu Feixiang Wei Kun Jiang Wenbin Xu 《Geodesy and Geodynamics》 EI CSCD 2023年第5期431-437,共7页
Sentinel-1A/B data are crucial for retrieving numerical information about surface phenomena and processes.Coregistration of terrain observation by progressive scans(TOPS)data is a critical step in its application.TOPS... Sentinel-1A/B data are crucial for retrieving numerical information about surface phenomena and processes.Coregistration of terrain observation by progressive scans(TOPS)data is a critical step in its application.TOPS data must be fundamentally co-registered with an accuracy of 0.001 pixels.However,various decorrelation factors due to natural vegetation and seasonal effects affect the coregistration accuracy of TOPS data.This paper proposed an enhanced spectral diversity coregistration method for dual-polarimetric(PolESD)Sentinel-1A/B TOPS data.The PolESD method suppresses speckle noise based on a unified non-local framework in dual-pol Synthetic Aperture Radar(SAR),and extracts the phase of the optimal polarization channel from the denoised polarimetric interferometric coherency matrix.Compared with the traditional ESD method developed for single-polarization data,the PolESD method can obtain more accurate coherence and phase and get more pixels for azimuth-offset estimation.In bare areas covered with low vegetation,the number of pixels selected by PolESD is more than the Boxcar method.It can also correct misregistration more effectively and eliminate phase jumps in the burst edge.Therefore,PolESD will help improve the application of TOPS data in low-coherence scenarios. 展开更多
关键词 COREGISTRATION Terrain observation by progressive scans (TOPS) Enhanced spectral diversity dual-polarIZATION
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Rapid-Scan and Polarimetric Phased-Array Radar Observations of a Tornado in the Pearl River Estuary 被引量:12
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作者 ZHANG Yu BAI Lan-qiang +3 位作者 MENG Zhi-yong CHEN Bing-hong TIAN Cong-cong FU Pei-ling 《Journal of Tropical Meteorology》 SCIE 2021年第1期81-86,共6页
The strong destructive winds during tornadoes can greatly threaten human life and destroy property.The increasing availability of visual and remote observations,especially by Doppler weather radars,is of great value i... The strong destructive winds during tornadoes can greatly threaten human life and destroy property.The increasing availability of visual and remote observations,especially by Doppler weather radars,is of great value in understanding tornado formation and issuing warnings to the public.In this study,we present the first documented tornado over water detected by a state-of-the-art dual-polarization phased-array radar(dual-PAR)in China.In contrast to new-generation weather radars,the dual-PAR shows great advantages in tornado detection for its high spatial resolution,reliable polarimetric variables,and rapid-scan strategy.The polarimetric signature of copolar cross-correlation coefficient with anomalously low magnitude appears to be effective for verifying a tornado and thus is helpful for issuing tornado warnings.The Guangdong Meteorological Service has been developing an experimental X-band dual-PAR network in the Pearl River Delta with the goal of deploying at least 40 advanced dual-PARs and other dual-polarization weather radars before 2035.This network is the first quasi-operational X-band dual-PAR network with unprecedented high coverage in the globe.With such high-performance close-range PARs,efficient operational nowcasting and warning services for small-scale,rapidly evolving,and damaging weather(e.g.,tornadoes,localized heavy rainfall,microbursts,and hail)can be expected. 展开更多
关键词 TORNADO waterspout phased-array radar dual-polarIZATION China
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Operational Evaluation of the Quantitative Precipitation Estimation by a CINRAD-SA Dual Polarization Radar System 被引量:6
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作者 CHEN Chao LIU Li-ping +3 位作者 HU Sheng WU Zhi-fang WU Chong ZHANG Yang 《Journal of Tropical Meteorology》 SCIE 2020年第2期176-187,共12页
In this paper,a quantitative precipitation estimation based on the hydrometeor classification(HCA-QPE)algorithm was proposed for the first operational S band dual-polarization radar upgraded from the CINRAD/SA radar o... In this paper,a quantitative precipitation estimation based on the hydrometeor classification(HCA-QPE)algorithm was proposed for the first operational S band dual-polarization radar upgraded from the CINRAD/SA radar of China.The HCA-QPE algorithm,localized Colorado State University-Hydrometeor Identification of Rainfall(CSUHIDRO)algorithm,the Joint Polarization Experiment(JPOLE)algorithm,and the dynamic Z-R relationships based on variational correction QPE(DRVC-QPE)algorithm were evaluated with the rainfall events from March 1 to October 30,2017 in Guangdong Province.The results indicated that even though the HCA-QPE algorithm did not use the observed rainfall data for correction,its estimation accuracy was better than that of the DRVC-QPE algorithm when the rainfall rate was greater than 5 mm h-1;and the stronger the rainfall intensity,the greater the QPE improvement.Besides,the HCA-QPE algorithm worked better than the localized CSU-HIDRO and JPOLE algorithms.This study preliminarily evaluated the improved accuracy of QPE by a dual-polarization radar system modified from CINRAD-SA radar. 展开更多
关键词 quantitative precipitation estimation operational QPE evaluation with dual-polarization radar optimization algorithm dual-polarization radar hydrometeor classification dynamic Z-R relations algorithm
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A Novel Kind of Wideband Low-Profile Dielectric Resonator Antenna Suitable for Beam-scanning Applications 被引量:1
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作者 Wenjian Sun Yang Yu +2 位作者 Yingdong Hu Wenwen Yang Jianxin Chen 《China Communications》 SCIE CSCD 2022年第4期98-107,共10页
In this paper, a low-profile wideband dielectric resonator antenna(DRA) with a very compact planar size is investigated. The antenna consists of a high permittivity dielectric sheet on the top, a low permittivity subs... In this paper, a low-profile wideband dielectric resonator antenna(DRA) with a very compact planar size is investigated. The antenna consists of a high permittivity dielectric sheet on the top, a low permittivity substrate in the middle, and a probe feeding structure at the bottom. By digging an annular slot in the designated area of the square dielectric sheet, the resonant frequency of fundamental TE111 mode can be effectively increased to be close to the high-order TE131 mode. The two modes can be finally merged together, yielding a wide impedance bandwidth of16.6%. Most importantly, the combination of the two modes is done on the premise of a fixed antenna planar size, which can be very compact and suitable for beam-scanning applications. A probe feeding structure is used to excite the DRA, making the antenna simple and practical to be integrated with other RF circuits. For verification, antenna prototypes with singlefeed linear polarization and differential-feed dual polarization were fabricated and measured. Reasonable agreement between the measured and simulated results is observed. 展开更多
关键词 dielectric resonator antenna COMPACT WIDEBAND beam-scanning dual-polarIZATION
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