电子与信息学报
電子與信息學報
전자여신식학보
JOURNAL OF ELECTRONICS & INFORMATION TECHNOLOGY
2014年
11期
2691-2697
,共7页
天波超视距雷达%多径扩展多普勒杂波%幅相误差校正%自适应数字波束形成
天波超視距雷達%多徑擴展多普勒雜波%幅相誤差校正%自適應數字波束形成
천파초시거뢰체%다경확전다보륵잡파%폭상오차교정%자괄응수자파속형성
Skywave Over The Horizon Radar (OTHR)%Multipath spread Doppler clutter%Amplitude and phase error correction%Adaptive Digital Beam Forming (ADBF)
该文分析了天波超视距雷达(Over The Horizon Radar, OTHR)多径扩展多普勒杂波(Spread Doppler Clutter, SDC)的产生机理。由于阵列存在幅相误差且期望信号的功率大于 SDC 功率,自适应数字波束形成(Adaptive Digital Beam Forming, ADBF)将降低SDC抑制能力,同时还会导致信号对消,严重降低信噪比。针对以上问题,该文提出一种自适应抑制SDC的方法。该方法首先采用改进噪声子空间拟合自校正法消除阵列幅相误差,得到期望信号和SDC准确的到达仰角,然后采用正交投影权矢量进行ADBF处理,避免了强期望信号条件下ADBF权矢量估计不准的问题。理论分析和仿真实验表明该方法能够较彻底地抑制多径SDC。
該文分析瞭天波超視距雷達(Over The Horizon Radar, OTHR)多徑擴展多普勒雜波(Spread Doppler Clutter, SDC)的產生機理。由于陣列存在幅相誤差且期望信號的功率大于 SDC 功率,自適應數字波束形成(Adaptive Digital Beam Forming, ADBF)將降低SDC抑製能力,同時還會導緻信號對消,嚴重降低信譟比。針對以上問題,該文提齣一種自適應抑製SDC的方法。該方法首先採用改進譟聲子空間擬閤自校正法消除陣列幅相誤差,得到期望信號和SDC準確的到達仰角,然後採用正交投影權矢量進行ADBF處理,避免瞭彊期望信號條件下ADBF權矢量估計不準的問題。理論分析和倣真實驗錶明該方法能夠較徹底地抑製多徑SDC。
해문분석료천파초시거뢰체(Over The Horizon Radar, OTHR)다경확전다보륵잡파(Spread Doppler Clutter, SDC)적산생궤리。유우진렬존재폭상오차차기망신호적공솔대우 SDC 공솔,자괄응수자파속형성(Adaptive Digital Beam Forming, ADBF)장강저SDC억제능력,동시환회도치신호대소,엄중강저신조비。침대이상문제,해문제출일충자괄응억제SDC적방법。해방법수선채용개진조성자공간의합자교정법소제진렬폭상오차,득도기망신호화SDC준학적도체앙각,연후채용정교투영권시량진행ADBF처리,피면료강기망신호조건하ADBF권시량고계불준적문제。이론분석화방진실험표명해방법능구교철저지억제다경SDC。
This paper analyzes the production mechanism of the multipath Spread Doppler Clutter (SDC) in skywave Over The Horizon Radar (OTHR). Because the amplitude and phase errors always exist in the array and the power of desired signal (sea clutter) is greater than the power of SDC, the SDC suppression ability declines through conventional Adaptive Digital Beam Forming (ADBF) process, at the same time, the desired signal is weakened and Signal-to-Noise Ratio (SNR) is seriously decreased. To resolve the above problems, an adaptive SDC suppression method is proposed. In this method, an improved Noise Subspace Fitting (NSF) method is utilized to eliminate amplitude and phase errors of OTHR array, and the direction of arrival angle of desired signal and SDC can be accurately obtained. Then, orthogonal projection weight vector is used in ADBF to solve the problem that conventional ADBF weight vector can not be accurately estimated because of the strong desired signal. Theoretical analysis and simulation results show that the scheme can completely suppress multipath SDC.