Joint optimal positioning method of time-frequency difference for satellite search and rescue system

Satellite search and rescue positioning technology can provide effective means for mountain areas, deserts, oceans and other areas lacking communication infrastructure, which has attracted more attention recently. In this paper, we propose a joint time-frequency difference optimal location method for satellite search and rescue system to improve the performance of parameter estimation and location solution in the traditional passive dual satellite time-frequency difference location technology. Specifically, the fast Fourier transform is used to simplify the joint estimation of the time-frequency difference of the cross ambiguity function. Aiming at the burst low duty cycle transmission of search and rescue signals, a time-domain windowed comprehensive cross ambiguity function calculation model is proposed. Finally, a genetic algorithm is proposed to solve the positioning equation. Simulation results show that, compared with traditional methods, the proposed algorithm can improve the system fault tolerance and positioning accuracy, and reduce the computational complexity.