Development of an Efficient Algorithm for Acquisition of GNSS Receiver Signals Using Parallel Code Phase Search Technique

Recent advances in GNSS technology make it possible to apply this technology with radio occultation and precise orbit determination purposes, among many other applications. This paper presents an optimized GNSS acquisition algorithm. It allows detecting efficiently the visible satellites that reach the carrier frequency and code phase with consideration of Doppler shifts. More importantly, the algorithm uses a Parallel Code Phase Search technique that involves circular correlation within the frequency domain for far reaching simplification in terms of computation. Furthermore, since it is implemented in MATLAB, along with one-on-one comparison through Verilog HDL implementations, the approach generates Pseudo-Random Noise (PRN) codes, conducts Fast Fourier Transforms (DFT), and then cross-correlates to ensure signal detection. The algorithm has been found to be effective and flexible. This was tested on synthesized datasets, where search combinations reduced from 41,943 to 41. Therefore, it is effective and diversified in real-time signal acquisition.