<b>Enhancement of GPS Signals Acquisition in non-Homogeneous Environment using the OS-CFAR Techniques with Optimization Technique</b>

In this paper, we propose to use metaheuristic optimization techniques to improve the adaptive acquisition of the global navigation satellite system (GNSS) in both homogeneous and non-homogeneous environments, The main objective of this work is to optimize the thresholding of the Constant False Alarm Rate (OS-CFAR) in Rayleigh fading channels we compare the result with the base detector CA-CFAR . In GNSS acquisition, the pilot and data blocks may have different thresholds. Therefore, the optimization will focus on two scaling factors (T and k). Two fusion rules have been used here "AND" and "OR". Due to their performance in different optimization problems, metaheuristics have been chosen as the tool to solve this type of problem. The simulation results show that the optimized thresholds have a significant impact on the performance of the acquisition system.