计算机应用与软件
計算機應用與軟件
계산궤응용여연건
COMPUTER APPLICATIONS AND SOFTWARE
2014年
2期
144-148,229
,共6页
GPS%弱信号%远近场效应%多径效应
GPS%弱信號%遠近場效應%多徑效應
GPS%약신호%원근장효응%다경효응
GPS%Weak signal%Near-far effect%Multi-path effect
针对在室内等弱信号环境下的GPS信号捕获，全面分析造成GPS接收机的远近效应的各种因素，包括GPS信号幅值差异引起的远近场效应、GPS信号中多普勒频移造成的远近场效应、GPS信号中多径造成的远近场效应等。针对不同情况造成的远近场效应，给出相应的改进算法，包括通过去强信号的自适应接收机结构克服强信号对弱信号的干扰；通过部分相关结构减小多普勒频移对相关结果的衰减；通过基于高阶循环统计量的时延估计，累积多径上的弱GPS信号，从而提高对期望GPS信号的捕获性能等。最后通过仿真验证了提出算法的有效性。
針對在室內等弱信號環境下的GPS信號捕穫，全麵分析造成GPS接收機的遠近效應的各種因素，包括GPS信號幅值差異引起的遠近場效應、GPS信號中多普勒頻移造成的遠近場效應、GPS信號中多徑造成的遠近場效應等。針對不同情況造成的遠近場效應，給齣相應的改進算法，包括通過去彊信號的自適應接收機結構剋服彊信號對弱信號的榦擾；通過部分相關結構減小多普勒頻移對相關結果的衰減；通過基于高階循環統計量的時延估計，纍積多徑上的弱GPS信號，從而提高對期望GPS信號的捕穫性能等。最後通過倣真驗證瞭提齣算法的有效性。
침대재실내등약신호배경하적GPS신호포획，전면분석조성GPS접수궤적원근효응적각충인소，포괄GPS신호폭치차이인기적원근장효응、GPS신호중다보륵빈이조성적원근장효응、GPS신호중다경조성적원근장효응등。침대불동정황조성적원근장효응，급출상응적개진산법，포괄통과거강신호적자괄응접수궤결구극복강신호대약신호적간우；통과부분상관결구감소다보륵빈이대상관결과적쇠감；통과기우고계순배통계량적시연고계，루적다경상적약GPS신호，종이제고대기망GPS신호적포획성능등。최후통과방진험증료제출산법적유효성。
In light of the GPS signal capture in the environment of indoor weak signal or so,in this paper we give a complete analysis on the factors which cause the near-far effects in GPS receiver,including the near-far field effects caused by amplitude difference of GPS signal, by Doppler frequency shift in GPS signal,and by multi-path effect in GPS signal,and so on.According to the near-far field effects incurred by different reasons,we propose corresponding improvement methods,such as to release the interference of strong signal on weak signal through the adaptive receiver scheme with strong signal removal,to decrease the correlation results attenuation caused by Doppler frequency shift through partial correlation scheme;and to accumulate the weak GPS signals in multi-path so as to improve the capture ability of expected GPS signal through time delay estimation of high order cyclic statistics.At last we verified the effectiveness of the proposed methods through simulations.
