Uniform and ununiform modulated constellation mapping based nonisoprotective mixed automatic retransmission inquiry method

Abstract

A unequal protection hybrid automatic retransfer request method based on equality and un-equality constellation diagram mapping, it is used in MQAM communication system with which the stage numbers is M and M=2, the modulation mapping of sending end and the resolving mapping of receiving end adopt constellation diagrams that have same distribution, in the first transmission and anterior m/2-1 time retransmission, adopts equality constellation diagram, at the m/2 time and the latter retransmission adopts un-equality constellation diagram, provides higher error protection for two most significant bit in the modification symbol; the bits un-equality protection in the modification symbol of sending end reset; uses m/2 reset and opposite reset rules, at different retransmission time adopts circularly in turn, achieves alternative protecting the bits in modulation symbol; the bits in modulation symbol of receiving end reset oppositely. Reset oppositely the bits according to the reset rules of sending end, recover it into bits sequence soft value before sending end bits resetting. It promotes the signals S/N of combining soft value after demodulating and resolving mapping at receiving end, reduces efficiently grouping retransmission time, makes the output of system maximum.

Description

Technical field [0001] The present invention relates to a wireless packet data transmission technology, in particular to a hybrid automatic repeat request (HARP) based on constellation diagram distribution adjustment and bit unequal error protection rearrangement in modulation symbols in a quadrature amplitude modulation (QAM, Quadrature Amplitude Modulation) communication system HARQ, Hybrid Automatic Repeat reQuest) transmission technology. Background technique [0002] In data communication, forward error correction and automatic retransmission request are two basic error control technologies. The automatic repeat request (ARQ, Automatic Repeat reQuest) technology is exchanged for the improvement of reliability at the cost of reducing the throughput rate, while the previous Forward Error Correction (FEC, Forward Error Correction) technology reduces the frequency of ARQ retransmissions by correcting some of the most frequently occurring error patterns, and maintains a cert...

AI Technical Summary

Problems solved by technology

However, this method requires both the transmitting and receiving ends to store all the additional constellation diagrams due to retransmission. In order to obtain better performance, 16QAM needs to use 4 different uniform constellation diagrams, and 64QAM needs to use 6 different uniform constellation diagrams. It greatly increases the storage capacity of the sending end and the receiving end, and it is also not conducive to the further use of symbol-level merging at the receiving end

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