Doppler compensation method for full arch satellite remote control

Abstract

The present invention provides a whole arc section satellite remote-control Doppler compensation method by calculating satellite orbit and using DDS to realize the compensation, wherein, the satellite orbits calculation method comprises that input data of earth station location coordinates (latitude, longitude and height), satellite transient Keplerian orbit 6 root number including major semi-axis, eccentricity, obliquity, right ascension of the ascending node and mean anomaly, and time point, earth station remote-control time period and time step, and remote-control signal carrier frequency, are used for performing geometry calculation to obtain accurate orbit location of the satellite within the remote-control time period, furthermore, a Doppler frequency bias value, a Doppler frequency first-order change rate and a Doppler frequency second-order change rate are obtained. The calculated Doppler corresponding data are transmitted to the DDS module to generate a frequency with a sign opposite to that of the Doppler frequency bias value and a same absolute value for modulating remote-control signals and generating Doppler frequency bias compensation. According to the present invention, after receiving remote-control signals, the satellite can realize capture of remote-control signal carriers by using a smaller phase-lock loop bandwidth, therefore, carrier capture time is shortened, carrier capture capability is improved, and interference to useful signals from the noise in the loop bandwidth is reduced.

Description

technical field [0001] The invention relates to a full-arc satellite remote control Doppler compensation method, which is mainly used for baseband processing of satellite remote control signals. Background technique [0002] When the ground station sends a remote control command signal to the satellite, due to the large radial velocity of the satellite relative to the ground station, the satellite will generate a large Doppler frequency shift in the signal when it receives the remote control signal. Due to the existence of Doppler frequency offset, the satellite needs to increase the loop bandwidth of the carrier phase-locked loop when processing the remote control signal. The increase will bring more noise to the remote control signal, reduce the signal-to-noise ratio, and degrade the communication quality. The existing Doppler compensation methods mainly use various algorithms to estimate the Doppler frequency offset. Due to the irregularity of the motion of the object us...

AI Technical Summary

Problems solved by technology

[0002] When the ground station sends a remote control command signal to the satellite, due to the relatively large radial velocity of the satellite relative to the ground station, the satellite will generate a large Doppler frequency shift in the signal when it receives the remote control signal

Due to the existence of Doppler frequency offset, the satellite needs to increase the loop bandwidth of the carrier phase-locked loop when processing the remote control signal. Increasing the size brings more noise to the remote control signal, reducing the signal-to-noise ratio and degrading the communication quality

The existing Doppler compensation methods mainly use various algorithms to estimate the Doppler frequency offset. Due to the irregularity of the motion of the object using Doppler compensation, these Doppler compensation methods often have low accuracy. The shortcomings of the carrier capture performance are limited

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