直序扩频信号PN码相位的自适应测量算法

提出了基于FFT的直序扩频信号PN码相位的自适应测量算法.算法首先利用FFT确定信号的可测性及可有效检测到目标信号的最低采样频率,并计算最低采样频率下信号的PN码相位,然后逐级提高采样频率,用循环卷积法求取各级采样频率下的PN码相位,直至达到测量精度要求.与其他基于FFT的方法相比,该算法可在同等测量精度要求下明显减少计算量,或在计算量相当情况下有效提高测量精度.该算法的主要应用领域为卫星定位信号和直序扩频测距信号PN码相位的精确测量.

Adaptive Algorithm for PN Code Phase Measuring of DS/SS Signals

An adaptive algorithm based on FFT for PN code phase measuring of DS/SS signals was proposed. The algorithm firstly determines the mensurability of the signals and the lowest sampling rate for correctly detecting the signals, and calculates the PN code phase at this sampling rate, then gradually increases the sampling rate and calculates the PN code phases at those sampling rates using circular convolution, until the expectant precision is acquired. Comparing with the other FFT-based methods, the proposed algorithm can effectively decrease the computation for given precision, or increase the precision with a similar computation. The algorithm is applicable to precise measuring of the PN code phase of satellite positioning signals and spread-spectrum ranging signals.