自适应非相干矢量跟踪环路设计

Self-adaptive non-coherent vector tracking loop design

针对导航接收机相关累加结果受导航电文数据比特跳变影响的问题,提出了一种自适应非相干矢量跟踪环路。通过在传统矢量跟踪环路中引入非相干频率/码鉴别器,使非相干与相干结合的相关器累加结果不再受比特跳变的影响。对非相干积分的灵敏度和动态性能进行了理论分析和仿真验证,同时给出了在一定动态范围内环路积分时间的优化选择方案,实现了环路积分时间在1~10 ms及非相干次数在1~10次的自适应调整设置。实验结果证明,自适应矢量非相干环路提升跟踪灵敏度约6 d B,非相干方法提高了矢量跟踪环路性能。

Aiming at the problem that the correlation results are influenced by navigation message data transition, a kind of self-adaptive non-coherent vector tracking loop is proposed. By applying non-coherent frequency/code discriminator in traditional vector tracking loop, the accumulation results of coherent correlators will not be affected by the data transition. The sensitivity and dynamic performance of non-coherent vector tracking loop is analyzed and simulated. The optimized selection scheme for the loop＇s integration time within specific dynamic range is provided, which realizes the self-adaptive adjustment within the integration time of 1 ms to 10ms and non-coherent times of 1 to 10. The experiment results show that the proposed non-coherent strategy increases the sensitivity by 6 dB, improving the tracking loop＇s performance.