Encoding method and decoding method of a turbo code

Abstract

The invention discloses a coding method and a decoding method of a Turbo code. In the coding method, on the one hand, the externally input information bit x(k) directly performs low-order modulation, and at this time, the output information bit is recorded as x''(k ); at the same time, the information bit x(k) is sent to the first sub-encoder; the first sub-encoder first receives the information bit x(k), and outputs the check bit y(k); at the same time, at the end of x(k) Add the return-to-zero bit, so that the first sub-encoder is in the zero state after encoding; record x(k) and the return-to-zero bit as x'(k); use the interleaver to scramble the order of x'(k) and send it later To the second sub-encoder, output the parity bit z(k); directly perform high-order modulation on the parity bit y(k) and z(k), and combine them into one symbol yz(k) to output simultaneously; put x'' After (k) and yz(k) are alternately switched by the multiplexing module mux, x''(k) and yz(k) are alternately output to obtain a data stream Rx(k), which is a 1 / 2 code rate. The invention realizes the good error correction capability of the Turbo code under the short code condition; and realizes better performance than the existing 1 / 3 code rate by using the 1 / 2 code rate. The invention is applicable to the field of digital communication.

Description

technical field [0001] The present invention relates to the field of digital communication, more specifically, relate to a kind of encoding method and decoding method of Turbo code. Background technique [0002] The Turbo code in the prior art is a high-performance error-correcting code that is very close to the Shannon limit, and the difference between its bit error rate curve and the theoretical limit can be less than 0.01dB. Existing Turbo codes are suitable for long frames containing thousands or more symbols in the data of each frame. In short frames with only dozens of symbols in each frame, especially in narrowband communication or fast frequency hopping communication, the error correction capability or coding gain of existing Turbo codes will decrease sharply. Compared with ordinary error-correcting codes, such as RS codes and convolutional codes, the existing Turbo codes have little improvement in their error-correcting capabilities in the case of complex operation...

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