非整周期扩频序列对导航接收机的影响

摘要

针对截断伪随机扩频序列相关特性不能由数学解析表达式给出的问题，采用计算截断伪随机序列相关最大旁瓣值的方法，确定了北斗与GPS操作者间频率协调的伪随机扩频码码簇，给出了截断非整周期伪随机扩频序列的相关特性与整周期序列的相关特性具有可比拟性的结论；基于双方所确定的伪随机扩频序列，分析了不同伪随机码码簇间的多址干扰，给出了不同系统伪随机码码簇间的多址干扰可使导航接收机的捕获相关损耗达到1～2 dB的结果。%Since the correlation properties of a truncated pseudorandom sequence can’ t be expressed by a mathematical formula, this paper describes a method to determine the spreading codes used in the frequency coordination between the operators of GPS and BeiDou by calculating the correlation maximum sidelobe. A conclusion is presented that the correlation properties are comparable between the full⁃period sequences and the truncated pseudorandom sequences. Based on the spreading codes chosen by GPS and BeiDou,the multi⁃access interferences between the spreading codes of both the systems are analyzed,and the multi⁃access interferences of the codes between the two systems can lead to 1 to 2 dB correlation loss of the receiver’ s acquisition of the navigation signals.