Layered cooperative transmission implementing method for wireless network

Abstract

Hierarchical modulation technique (HMT) based on code cooperation protocol is adopted in radio communication network to transmit radio signal in cooperation. When transmitting data for associated terminal in cooperation, a mobile terminal multiplexes own and associated data symbols in low order modulation to high order modulation to carry out synergetic transmission. Modulating own data (or data of associated terminal) to bit position in high reliability (or low reliability), the mobile meets QoS requirements of different terminals by adjusting diversity factors of transmission reliability of bit in different positions in HMT. Making compromise between technical implementation and QoS requirement, the method obtains diversity gains in both of space and time so as to improve transmission performance of each terminal effectively. When network can implement synchronization of symbols accurately, the method obtains larger diversity gains by using scheme of combining space with time.

Description

Technical field [0001] The present invention relates to a method for implementing coordinated transmission in a wireless network, specifically, to a method for implementing layered coordinated transmission of wireless signals in which layered modulation technology is applied to a coordinated network, and belongs to the field of wireless communication technology. Background technique [0002] MIMO (Multiple-Input Multiple-Out-put) technology is a technology that uses multiple transmitting antennas and multiple receiving antennas for wireless transmission. Its main feature is to transform the multipath propagation environment into a factor beneficial to users: using MIMO channels to provide The spatial multiplexing gain is used to increase the capacity of the channel, while the spatial diversity gain provided by the MIMO channel is used to effectively eliminate the effects of multipath and time-varying fading of the wireless channel, improve the reliability of signal transmission, ...

AI Technical Summary

Problems solved by technology

[0029] Although in the fast-fading wireless channel environment, the above-mentioned space-time coding coordination technical scheme can obtain the diversity gain in space and time at the same time, but this scheme requires that each symbol transmitted by the two mobile terminals A and B must be strictly synchronized

Because space-time codes are very sensitive to inter-symbol asynchrony, it will lead to a sharp drop in performance, and in practical cooperative networks, such precise synchronization between symbols is difficult to achieve, especially in TDMA systems

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