Blind estimation method for large frequency bias in ground digital television system and apparatus thereof

Abstract

The invention discloses a large frequency hemiopia estimation method, which is carried out according to circular correlation property of receiving data without using auxiliary data, of a digital television terrestrial broadcasting transmission system receiver and a device thereof, belonging to the processing field of digital information. The invention adopts a digital intermediate signal which is subjected to A / D sampling to be multiplied by a local carrier signal so as to carry out digital down conversion and then forms filtering by a square root raising cosine (SRRC) filter. A complex signal output by the SRRC filter is delayed for Tau sampling points and subjected to conjugation-obtaining, and the delayed and conjugated complex signal is subjected to re-multiplication with the original signal before being delayed. The result of re-multiplication is divided into p branches for summarizing, the results of the p branches are subjected to FFT of p point, and then the estimation value of the frequency offset is obtained. The invention is applicable to the frame structures of two modes: single carrier and multi-carrier, can carry out blind estimation on the frequency offset under the state without any auxiliary information, and has the advantages of large scale of frequency offset estimation, good noise immunity, being suitable for hardware realization and the like.

Description

technical field [0001] The invention relates to a large frequency offset blind estimation method and a device thereof in a terrestrial digital television system, and belongs to the field of digital information transmission. Background technique [0002] The development of the TV industry and business has always been centered on the improvement of viewing quality and service capabilities. As a new generation of TV technology, digital TV has greatly improved its viewing quality; at the same time, the adoption of digital technology has created more opportunities for other services. Expansion capacity. The development of digital TV will be of great significance to the development of the entire electronic information industry. [0003] Digital TV terrestrial broadcasting system is an important part of broadcasting TV system. It cooperates with satellite digital TV broadcasting system, cable digital TV broadcasting system and other auxiliary systems to provide comprehensive audi...

AI Technical Summary

Problems solved by technology

The European Code Orthogonal Frequency Division Multiplexing (COFDM for short) system adds a special structure in the time domain - a cyclic prefix, and uses coarse and fine synchronization estimation to ensure a larger capture range and Optimize the tracking performance, but the Inter-Symbol Interference (ISI) introduced by the multipath channel will destroy this special structure and affect the performance of carrier estimation

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