Deep Investigation of Coherent Integral Acquisition Algorithm of GNSS Signals

Abstract

Autonomous navigation places an extremely high demand on the acquisition sensitivity of the global navigation satellite system (GNSS) receivers. To increase the efficiency and sensitivity of the acquisition algorithm of GNSS weak signal, we ipmrove the acquisition algorithm named Improved Acquisition Algorithm with Doppler Frequency Compensation (IAADFC) proposed in our previous study. We provide a detailed analysis and comparison among the proposed IAADFC algorithm, non coherent integration (NCI) algorithm and double block zero padding (DBZP) algorithm. Simulation results show that the weak signal acquisition ability of IAADFC algorithm and DBZP algorithm can be improved by increasing the coherent integration time CIT and the acquisition sensitivity of IAADFC algorithm is higher than that of the DBZP algorithm. What’s more, the acquisition sensitivity of IAADFC algorithm and DBZP algorithm can be significantly improved by estimating and correcting navigation message bit flip or transition using DBST algorithm.