Assisted GPS signal acquisition algorithm based on the joint code-frequency search

Signal acquisition by GPS receiver is an important part both in navigation and positioning, thus reducing the complexities of signal acquisition and acquisition time is important. Since the grid of frequencies in joint code-frequency search algorithm is fixed, the amount of calculation is large in specific cases. Besides, under the condition that the receiver can obtain assistant information, the limited code-phase search algorithm has the problem of peak degradation, and the complexity is still high. Therefore, we propose an assisted GPS signal acquisition algorithm based on joint code-frequency search algorithm. The grid of frequency is modified and the code-phase search of the algorithm is realized in the time domain, the problems of the joint code-frequency search algorithm and the limited code-phase search algorithm is resolved. Simulation results show that the complexity of the proposed assisted GPS signal acquisition is reduced, moreover, the acquisition performance is improved as well.