Comparison Framework of FPGA-Based GNSS Signals Acquisition Architectures

The acquisition of Global Navigation Satellite Systems (GNSS) signals using code division multiple access (CDMA) can be performed through classical correlation or using a Fourier transform. These methods are well known, but what is missing is a comparison of their performance for a given hardware area or target. The work reported here presents this comparison for field-programmable gate arrays (FPGAs), describing the different parameters involved in the acquisition, detailing some optimized implementations where hardware elements are duplicated, and estimating and discussing the performances. The influence of the Doppler effect on the code is also discussed as it plays an important role, particularly for new signals using a high chipping rate.