Device and method for estimating and compensating sampling clock offset of handset television terminal

Abstract

The invention provides a device for estimating and compensating sampling clock offset of a handset television terminal, comprising the following modules of an over-sampling interpolation filter module, an FFT/descrambling module, a continuous pilot extraction module, a sampling clock offset estimation module and a sampling clock offset control module, wherein the over-sampling interpolation filter module completes the over-sampling interpolation, filtering and desampling extraction of the input data and adjusts the sampling clock offset according to the final sampling clock offset estimation result; the FFT/descrambling module carries out FFT operation and descrambling treatment; the continuous pilot extraction module extracts continuous pilot sub-carrier data from the descrambled data; the sampling block offset estimation module completes the estimation of the sampling clock offset; and the sampling clock offset control module obtains the final sampling clock offset estimation result according to the provided estimation results and supplies the results to the over-sampling interpolation filter module. Simultaneously, the invention provides a method for estimating and compensating sampling clock offset of a handset television terminal. The device and the method can simplify the treatment and ensure receiving performance.

Description

technical field [0001] The present invention relates to the field of Orthogonal Frequency Division Multiplex (OFDM) communication, in particular to a device and method for estimating and compensating the sampling clock deviation of China Mobile Multimedia Broadcasting (CMMB) system. Background technique [0002] Orthogonal frequency division multiplexing technology transmits data in parallel through a group of orthogonal subcarriers, which can effectively reduce the impact of wireless multipath propagation environment, and has been more and more widely used in the field of wireless broadband communication. [0003] Orthogonal frequency division multiplexing technology uses the characteristics of orthogonal subcarrier transmission to determine its sensitivity to frequency synchronization errors; in mobile communication systems, there is usually a certain gap between the local oscillator clock of the terminal receiver and the clock of the transmitting tower. Deviation, the dev...

AI Technical Summary

Problems solved by technology

[0004] At present, the China Mobile Multimedia Broadcasting CMMB standard adopts OFDM as the transmission technology of the physical layer. In order to reduce the cost of CMMB terminals and improve product competitiveness, passive crystals with low cost and poor frequency stability are usually required. As a receiving clock source, it will bring a large sampling clock deviation. At this time, it is necessary to estimate and compensate the sampling clock deviation to ensure the receiving performance.

[0005] At present, the commonly used sampling clock deviation estimation and compensation method is to estimate the sampling frequency deviation and then feed back to the sampling clock source to reduce the sampling clock deviation and achieve the purpose of compensation. This method cannot be applied to the case of passive crystal as the sampling clock source;

[0006] There is also a digital method to correct the phase rotation between symbols and subcarriers in the frequency domain by estimating the sampling frequency deviation. Since the phase compensation amounts of different subcarrier indexes are different, this method is more complicated to implement.

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