GNSS数字接收机中载波锁相环的工作带宽

Carrier PLL bandwidth in GNSS digital receiver

首先对二象限反正切鉴相器输出的连续信号进行时域分析,并对其物理规律进行讨论。在此基础上研究了数字锁相环系统中预检测积分时间对鉴相器工作带宽的影响,发现鉴相器工作带宽的上界理论值与预检测积分时间之间存在反比关系,并给出了相应的关系公式。最后,通过系统仿真和对真实卫星信号的试验,验证理论研究成果的正确性。

Based on the time domain analysis of the continual signals which are produced by atan phase detector in the carrier phase-locked loop（PLL）,Some physical laws about these signals are given.Then study the influence of the pre-detection integral time on the bandwidth of phase detector in carrier PLL,and derive a formula expressing the relationship between theoretical maximum value of the bandwidth and the pre-detection integral time.Finally,the theoretical simulation and experiment results confirm that the research conclusionis accurate.