System and method for adjusting frequency offset of communication signals

Abstract

The invention provides a system for adjusting frequency offset of communication signals, which comprises a signal reception unit, a synchronization unit, a frequency offset estimation unit, a frequency offset configuration unit, a synchronous down-sampling unit, a frequency offset compensation unit and a signal selection unit. The signal reception unit is used for receiving digital sampling signals; the synchronization unit is used for carrying out timing synchronization on the received digital sampling signals; the frequency offset estimation unit is used for estimating frequency offset of the digital sampling singles after timing synchronization; the frequency offset configuration unit is used for configuring frequency offset values for compensating frequency offset of multiple branches according to estimation values of the frequency offset; the synchronous down-sampling unit is used for carrying out synchronous down-sampling on the digital sampling signals after the timing synchronization to obtain sampling baseband signals; the frequency offset compensation unit is used for compensating the frequency offset of the multiple branches according to the frequency offset values and the baseband signals of synchronous down-sampling; and the signal selection unit is used for selecting an optimal signal from the signals after frequency offset compensation. A method for adjusting the frequency offset of the communication signals, provided by the utility model, can effectively reduce frequency offset influence of the system, and improve receiver performance and communication quality of the system.

Description

technical field [0001] The invention relates to the field of mobile communication signal processing, in particular to a communication signal frequency offset adjustment system and method. Background technique [0002] Because there is a certain movement in the mobile user terminal while sending the message signal, the base station is in a state of motion relative to the user terminal, and when the receiver is in a state of motion at a certain rate relative to the transmitter, the frequency of the received signal will shift ( Doppler shift phenomenon). When the frequency offset is too large, the communication quality will be degraded. In order to eliminate the adverse effect caused by Doppler frequency shift, the automatic frequency control (AFC) algorithm is used in the communication system to correct the signal frequency deviation in real time and improve the communication quality. [0003] However, the AFC technology cannot effectively reduce the frequency offset caused ...

AI Technical Summary

Problems solved by technology

[0003] However, the AFC technology is not able to effectively reduce the frequency offset caused by the Doppler frequency shift effect in all cases, and the communication quality cannot be guaranteed

When the mobile speed of the user terminal is not large, the correction effect of AFC technology on the resulting Doppler frequency shift is not obvious, and sometimes even side effects occur, which reduces the performance of receiving demodulation

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