Soft Information Based Distributed Space-Time Trellis Code Relay Transmission Method

Abstract

Provided is a distributed space-time trellis code relay transmission method based on soft information. The method mainly solves the problems that an existing relay cooperation technology is low in coding gain and spectral efficiency, and error propagation influences frame error rate performance. The method comprises the steps that (1) source node coded modulation is carried out; (2) a source node broadcasts messages; (3) relay node soft decoding is carried out; (4) soft coded modulation of a relay node is carried out; (5) the relay node calculates the equivalent average value and the equivalent noise variance of soft signals and sends the equivalent average value and equivalent noise variance signals to a destination node; (6) the source node and the relay node send signals to the destination node at the same time; (7) the destination node carries out decoding. Distributed space-time trellis coding is adopted in the method, and the method has the advantage of being high in coding gain and spectral efficiency. A soft information coding and decoding method is adopted by a relay, the error propagation can be effectively restrained, the frame error rate performance can be improved, and the method is made to be suitable for real wireless communication scenes better.

Description

technical field [0001] The invention belongs to the field of communication technology, and further relates to a soft information-based distributed space-time lattice code relay transmission method in the field of space-time coding technology and relay cooperative communication technology. The present invention uses the relay transmission and encoding and decoding method combining the soft information forwarding protocol and the distributed space-time grid code for the relay cooperative communication network, which can reduce the impact of error propagation on the performance of the distributed space-time grid code and improve the performance of the distributed space-time grid code. Frame Error Rate Performance of Following Cooperative Communication Networks. Background technique [0002] Using relay nodes to help mobile users forward data can obtain additional diversity gain and improve the bit error performance of the receiving end, which is one of the effective means to im...

AI Technical Summary

Problems solved by technology

The shortcomings of this method are: firstly, the space-time block code cannot provide coding gain, and the error correction performance is not as good as that of the space-time trellis code; secondly, when a single relay cooperates, the source and the relay send a space-time code word time-sharing , the spectral efficiency is low

However, the disadvantage of this method is that if the relay decodes incorrectly and re-encodes and forwards the incorrectly decoded signal, it will cause error propagation and seriously affect the performance of the network frame error rate.

Therefore, this method is not practical in actual communication with poor relay decoding conditions.

Images