A DTO and DFO estimation algorithm of broadband frequency-hopping pulse signal

By measuring the DTO (differential time offset) and DFO (differential frequency offset) from two satellites, the emitter´s position can be estimated by dual LEO-satellites location system. But it is difficult for broadband frequency-hopping pulse signal, because the pulses of different frequency points can´t be accumulated due to doppler varying with carrier frequency. On the other hand, the parameter estimation accuracy of single frequency pulses can´t satisfy the final request of location system. An algorithm is proposed for DTO and DFO estimation of broadband frequency-hopping pulse signal, by utilizing the DFO and location estimate of single frequency pulses to correct additional phase and compensate differential doppler of other frequency points. By adopting the proposed algorithm, the parameter estimation and location accuracy can be greatly improved without increasing the observation interval. By Monte-Carlo simulations, the proposed algorithm is proved.