Method for measuring and compensating satellite communication link carrier frequency offset

Abstract

The invention relates to a method for measuring and compensating satellite communication link carrier frequency offset, which comprises the following steps: firstly, carrying out matched filtering and demodulation for baseband data, carrying out correlation operation for the baseband data and multiple orthogonal carriers, and taking the frequency value corresponding to the maximum correlation peak as a rough estimate value of carrier frequency offset; subdividing frequency points near the rough estimate value, re-setting the frequency parameters of the multiple orthogonal carriers, generatingnew orthogonal carriers and carrying out the correlation operation over again, and looping until the frequency value and phase corresponding to the maximum correlation peak which meet precision requirements are found to be used as the precise estimate value of the carrier frequency offset; and finally, utilizing a sine look-up table to generate two orthogonal single-carriers according to precise frequency offset information, multiplying baseband data stream by the two orthogonal single-carriers through a complex multiplier to obtain data stream after removing frequency offset. The method can meet the real-time requirements of receiving burst data in an MF-TDMA mode, takes less hardware resources, and has small additional delay and simple and convenient realization.

Description

technical field [0001] The invention relates to a method for calculating carrier frequency deviation of a satellite communication link, which is used for receiving data sent in MF-TDMA mode and removing the carrier frequency deviation in the communication link. Background technique [0002] Digital satellite communication systems are currently widely used at home and abroad, especially in Europe and the United States, where a large number of digital satellite communication systems are used as a supplement and extension of ground communication systems. Its users involve banking, transportation, entertainment, shopping, postal services, and live TV. In recent years, my country's satellite application business has developed rapidly, and many satellite communication systems have been built, especially interactive TV service systems and satellite TV live broadcast services are being vigorously promoted. As an important part of modern communication technology, satellite communicat...

AI Technical Summary

Problems solved by technology

This requires finding a method that can effectively capture burst data and estimate and compensate frequency offset without taking up too many resources and adding too much link delay

At present, the more commonly used method is to add a pseudo-random sequence to the head of the burst data at the sending end, and at the same time perform FFT operation on the demodulated data stream at the receiving end. This method has strong requirements for real-time data processing, and the algorithm High complexity, very difficult to implement

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