实时GNSS软件接收机并行相关器设计

Design of a Real-Time GNSS Software Receiver Parallel Correlator

为了改进软件接收机的实时性，提出了一种新的并行相关器设计，不再采取常用的查找表方法，而是利用基于位操作的并行算法，以及处理器的SIMD（单指令多数据）指令集，分别对相关器中的乘法与求和运算进行了优化。新方法可适应各种信号量化位数，比现有算法性能提升4～10倍，在普通计算机上并行处理12通道的GPSL1频点信号时，处理器资源占用率不到1％。

In order to improve the real-time performance of the software receiver, a new parallel correlator is designed. It does not adopt a common look-up table method, but uses bit-wise based operating parallel algorithms and Single Instruction Multiple Data （SIMD） instruction set to optimize the operation of multiplication and summation of the correiator respectively. The new method can be adapted to various signal quantization bits, and its performance increases by 4 to 10 times than the existing algorithm. When tracking 12 channels GPS L1 signals, the new method uses less than 1% of the CPU occupied rate.