基于互相关函数重构的BOC信号无模糊捕获算法的FPGA设计与实现

FPGA Design and Implementation of Unambiguous Acquisition Algorithm for BOC Signal Based on Reconstructed Cross-correlation Function

BOC信号自相关函数的多峰特性是造成捕获模糊性的直接原因,基于互相关函数重构的BOC信号无模糊捕获算法能够消除BOC信号的捕获模糊性,提高伪码相位的测量精度。对算法进行FPGA设计与实现,并通过Matlab、Modelsim和SignalTap-II进行验证。测试结果表明,算法能够成功捕获到BOC信号,并且SignalTap-II中采集到的多普勒频率及码相位捕获结果与Matlab中计算结果一致,在验证算法可行性的同时证明了FPGA设计的正确性。基于互相关函数重构的BOC信号无模糊捕获算法易于工程实现,具有较高的工程实用价值。

The autocorrelation function of BOC signal has multiple side-peaks which lead to the acquisition ambiguity.The unambiguous acquisition algorithm based on reconstructed cross-correlation function can eliminate the ambiguity of BOC signal and improve the accuracy of pseudo code phase measurement. The algorithm is designed and implemented by FPGA in this paper, and verified by Matlab, Modelsim and SignalTap-II. Test results show that the algorithm can successfully acquire BOC signal, and the Doppler frequency and chip offset acquisition results in SignalTap-II are consistent with the calculation results in Matlab, which proves that the algorithm is feasible and the FPGA design is correct. The unambiguous acquisition algorithm for BOC signal based on reconstructed cross-correlation function is easy to realize in engineering and has good practical value.