GPS L5信号双分量联合跟踪

GPS Block-IIF卫星发射的L5信号为许多新的GPS应用敞开了大门.本文探讨不同的L5信号跟踪策略,包括单导频跟踪、单数据跟踪和双分量联合跟踪;着重研究联合跟踪方式下3种不同组合方法的跟踪门限和跟踪精度,并基于所仿真的数字中频信号的跟踪结果进行了测试和评估.结果表明,对于载波跟踪,相关器输出组合方式跟踪精度最高,但是其跟踪门限介于单数据分量跟踪和单导频分量跟踪之间;对于码跟踪,滤波器输出组合方式只有在低信噪比时其跟踪精度才会略优于相关器输出组合方式,但是其接收机实现上需要用到双倍的码鉴别器和滤波器,复杂度稍高.文中对于所采集的SVN62信号的处理结果同样证明了这些结论.

Dual-component Combined Tracking of GPS L5 Signals

The transmission of GPS L5 signal in Block-IIF satellites opens the door for many new GPS applications.This paper explores different tracking strategies of L5 signals,including pilot only tracking,data only tracking and dual-component combined tracking.The tracking threshold and accuracy of different combination methods for PLL and DLL of combined tracking are evaluated using the tracking results of simulated digital IF signals.For carrier tracking,the correlator-output-combination achieves the highest accuracy but its tracking threshold is between that of pilot only tracking and data only tracking.For code tracking,the tracking accuracy of the filter-output-combination outperforms the correlator-output-combination a bit only at low C/N0s but at the cost of two independent code discriminators and filters.The processing results of collected SVN62 signals are also included to support the analysis.