Abstract:

Based on the framework of “Multi-bank matched filter + FFT”, a new acquisition algorithm is proposed and implemented, which is based on time and frequency domain parallel search and applicable to P code direct acquisition in GPS (Global Positioning System) high dynamic situation. Its novelty is multi-bank matched filter’s implementation in the structure of “folded filters + re-order RAM” and its FPGA implementation in parallel. The pipelined implementation shows that the new algorithm occupies about 1/16 of the old one. Simulation results and field tests show the algorithm improves P code direct acquisition performance in GPS high dynamic situation.

Key words: acquisition, matched filters, folded filters, FPGA