Research On Multi-user Interference Cooperative Transmission On MIMO Relay Channel

In recent years,the number of wireless communication users is increasing with the rapid development of wireless communication technology.Especially the rise of Mobile Internet making the number of users and the user demands for diversified services increased rapidly.However,the shortage of wireless resources poses a huge challenge to existing communication technologies and those network topology.How to use the limited wireless resources to improve the capacity of communication system has become a hot research issue.Recent research results have shown that Multiple-Input Multiple-Output(MIMO)can increase capacity without increasing the wireless resource or transmission power.As a new type of multiple access,Signal Space Alignment(SSA)technology can reduce the space dimensions occupied by signals through the multiple antennas at nodes,it can enchance the utilization of space resources.In recent years,there are so many research about the SSA technology have carried out by scholars,but most of them focus on the classical channel system with symmetric information flow.Its research results have limitations in practical application.Therefore,in this paper,We focuses on the multi-user MIMO multi-way relay(MU-MIMO MWR)system with asymmetric information flow.Combined with the existing signal alignment technology,A new transmission algorithm by applying a new signal alignment approach is proposed,Which can enhancing the system capacity further.Paper's main work are as follows:Firstly,this paper presents a multi-user MIMO wireless relay transmission scheme which based on round-robin programming by the transmission characteristics of asymmetric information flows.The scheme distributes the system Do F tuple and the relay resource reasonably by using transmission efficiency to realizes the efficient competition of the system resources.Secondly,the definition of the Do F region of the 4-user MIMO MWR channel is given.And then,the achievability of the Do F tuple which in the Do F region is proved through the algorithm design.At the same time,the antenna constraint condition of the algorithm is also analyzed.This algorithm performs the alignment of the signals by jointly designing the pre-processing matrice at the relay and the precoding matrices at all source nodes.It overcomes the limitations of traditional SSA technology which mainly used in the channel models with symmetric data streams.And on this basis,The algorithm is extended to the K users,which makes it possible to achieve the Do F tuples in the Do F region.Finally,the Do F upper bound and the sum-rate of the system are analyzed.It is proved that the algorithm not only expand the achievable range of the Do F upper bound but also reduce the number of antennas required by the system.At the same time,the channel model in this paper can be modeled into a variety of classical channel models by selecting the number of independent signal streams according to the actual communication scenarios,the simulation results show that our transmission algorithm covers the existing classical channel models and can realize the similar system performance as their respective algorithms,which is proved that the algorithm described in this paper has the flexibility and universality.