Codeless Doppler Orbit Determination Method Based on Non-Cooperative Navigation Satellite Signals

Abstract

The invention discloses a codeless Doppler orbit determination method based on non-cooperative navigation satellite signals. Navigation satellite signals are converted into digital intermediate frequency signals via the radio frequency front-end of a receiver, continuous carrier signals are obtained after performing code elimination processing on the intermediate frequency signals, and initial frequency of the carrier signals is estimated; the frequency value acts as the initial value of phase locked loop tracking, reinsertion of carrier is performed and Doppler frequency shift of each navigational star signal is extracted through measurement; then a navigational star corresponding to certain frequency shift is searched by adopting a matching algorithm based on the Doppler frequency shift characteristics; and a high-precision measurement model is established, and high-precision orbit parameters are estimated by adopting a Kalman filter through combination of an orbit dynamical model. High-precision orbit determination can be realized by utilizing the encrypted navigation signals transmitted by a satellite navigation system under the situation that plain code signals are not available.

Description

technical field [0001] The invention belongs to the technical field of satellite navigation, and in particular relates to a codeless Doppler orbit determination method based on non-cooperative navigation satellite signals. Background technique [0002] The precise measurement of satellite orbit is the basis of satellite application. At present, the orbit determination method used at home and abroad mainly relies on the ground-based measurement and control network, and combines the on-board transponder to obtain the distance measurement and speed measurement information, and then precisely corrects the orbit and adds the note. However, this orbit determination method is not only difficult to survive in harsh environments. , and the orbit determination accuracy is on the order of 100 meters to 10 meters, and the accuracy gradually decreases with the on-board orbit prediction, and sometimes it is difficult to meet the accuracy requirements. [0003] The DORIS orbit determinati...

AI Technical Summary

Problems solved by technology

However, the GPS satellite navigation system is controlled by the foreign military. In harsh environments, the clear signal is at risk of being shut down. In this way, the satellite pseudo-range and pseudo-range rate cannot be obtained through ordinary receivers, and positioning and orbit determination cannot be achieved.

my country's Beidou system is currently a regional navigation system, which cannot yet achieve full orbital coverage

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