Double-layer lengthened LDPC (Low Density Parity Check) code-based relay transmission method

Abstract

The invention discloses a double-layer lengthened LDPC (Low Density Parity Check) code-based relay transmission method, which mainly solves the problems of local optimization of a double-layer lengthened LDPC code and high complexity existing in the prior art. The method is implemented through the following steps: (1) broadcasting a message by a source node; (2) decoding by a relay node; (3) coding by the relay node; (4) modulating by the relay node; (5) forwarding by the relay node; (6) decoding by a destination node. According to the method, an integral optimization method is adopted during design of the double-layer lengthened low-density parity check code, and the transmission rates in two links of a full duplex relay channel can be kept maximum simultaneously; a double-layer gaussian approximate density evolution algorithm is adopted during optimization of the double-layer lengthened low-density parity check code, so that the method has the advantage of low decoding complexity and is suitable for an actual wireless communication system.

Description

technical field [0001] The present invention belongs to the technical field of communication, and further relates to a relay transmission method based on double-layer extended low-density parity-check (Low-Density Parity-Check, LDPC) code in the technical field of wireless communication. The invention can be used in a single-source single-relay network, and realizes a transmission method for relay nodes decoding and forwarding check messages based on double-layer extended low-density parity check codes. Background technique [0002] Low-density parity-check codes are a kind of special linear block codes based on sparse check matrix proposed by Gallager in 1962. Low-density parity-check codes not only have good performance close to the Shannon limit, but also have low decoding complexity, high throughput, and flexible structure. They are research hotspots in the field of channel coding in recent years. Optical fiber communication, terrestrial and satellite digital multimedia...

AI Technical Summary

Problems solved by technology

The disadvantage of this method is that in the process of expanding the parity check matrix corresponding to a part of the codeword to the parity check matrix corresponding to the complete codeword, since this method uses a simple row-column decomposition, it does not achieve the optimum of the two-part matrix. Combination, in the actual communication system, the lowest error probability of information transmission cannot be achieved

The disadvantages of this method are: firstly, the density evolution algorithm used in this method is very complicated to implement, and it is difficult to realize in the actual communication system; secondly, the optimization algorithm used in this method only applies The two links to the destination are optimized separately, without considering the overall optimization of the double-layer extended low-density parity check code, and the transmission rate of the two links cannot be maximized simultaneously in the full-duplex channel.

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