Interference suppression method for multi-user MIMO collaborative relay system

Abstract

The invention discloses an interference suppression method for a multi-user MIMO collaborative relay system, mainly solving the problem that each user has multiple antennas in a common-channel multi-user relay system. The interference suppression method comprises the steps that: a user determines a beamforming vector by adopting a signal space alignment method, and sends out a signal after weighting the signal with the beamforming vector in a multiple-access time slot; a relay constructs a precoding matrix based on an orthogonal projection principle, and amplifies and sends the received signal after precoding; the user receives the signal and suppresses interference signals between user pairs by adopting a decoding vector, and conducts a maximum likelihood detection to obtain the needed signal. According to the invention, a network transmission rate and a resource utilization rate are improved, diversity gains of multiple antennas are achieved, channel fading resisting capability of the system is enhanced, and a bit error ratio is decreased. Further, the interference suppression method of the invention can be applied in a transmission mode under centralized management and control of a wireless ad hoc network and base station, wherein data can be exchanged directly through user-relay-user mode.

Description

technical field [0001] The invention belongs to the technical field of communication, and relates to a signal space alignment method, in particular to an interference suppression method for a multi-user MIMO cooperative relay system, which can be used for wireless communication. Background technique [0002] In real life, real-time and reliable two-way communication is often required, such as real-time file interaction between users, video calls and dedicated monitoring systems. Two-way communication requires that both ends of the communication can send and receive signals at the same time. Due to the geographical distance or the poor quality of the direct transmission channel, users who expect to achieve two-way communication cannot form a network to achieve reliable communication. At this time, relay assistance can be used to complete two-way communication . Relays are generally divided into two modes, namely decoding and forwarding type DF and amplification and forwardin...

AI Technical Summary

Problems solved by technology

The disadvantage of this patent application is: under the same time-frequency resources, the relay can only realize the information exchange between two users, and cannot realize the two-way information transmission of multiple user pairs, which reduces the network transmission rate and system capacity

The disadvantage of this patent application is that this method is only applicable to the scenario where the user configures a single antenna, but not applicable to the scenario where the user configures multiple antennas, so that the potential diversity gain cannot be obtained, and the system's ability to resist channel fading is weak

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