基于共轭差分的弱信号捕获方法性能分析  

Performance Evaluation of Weak Signal Acquisition Based on Differential Integration

作　　者：谢金石[1] 

机构地区：[1]中国人民解放军61081部队

出　　处：《无线电工程》2010年第6期21-23,30,共4页Radio Engineering

摘　　要：传统基于包络检波的捕获方法由于平方损耗太大已不适用弱信号条件下的全球导航系统(GNSS)信号捕获。介绍了一种新的检波方法——共轭差分检波来取代传统的包络检波,为弱信号条件下GNSS接收机的捕获设计提供了理论依据。理论分析表明,共轭差分检波在弱信号条件下引入的检波损耗远低于包络检波,并且共轭差分检波通过改善噪声的统计特性提高了后处理增益。通过仿真实验验证了理论分析的正确性。Signal acquisition is the key phase of GNSS signal processing.In weak signal environment,the GNSS signal is normally 10 dB to 30 dB lower than that of the line of sight （LOS） signal,and the conventional acquisition method based on non-coherent integration is not adequate due to the squaring loss.In the paper,a new acquisition method based on differential integration is presented for GNSS receiver design in weak signal circumstance.Theoretical analysis shows that the proposed method introduces much lower demodulation loss than the conventional method,and enhances the post-accumulation gain due to the improved statistical character of the noise.At last,MATAB simulation result verifies the validity of the theoretical analysis.

关 键 词：GNSS接收机 弱信号捕获 共轭差分 

分 类 号：TN911.6[电子电信—通信与信息系统]