Research On Physical-layer Network Coding Algorithm In MIMO Two-way Relay Channel

In recent years, wireless communication network system as in people's daily lives in popularity for people to bring a faster, more convenient life. However, due to the diversity and the complexity of wireless network transmission environment, making high-speed transmission of data in a wireless network environment is faced enormous difficulties.Multiple Input Multiple Output and Physical-layer Network Coding came into being in this situation. Under no circumstances additional bandwidth, MIMO effectively improve the spectrum utilization efficiency of the radio communication network system, and improves the data transfer rate. PNC promotes the network coding ideas in cable network to the wireless communication network system. It makes the relays be able to do some processing to the received packets. PNC solve the mutual signal interference in the wireless network and improve the network throughput.Pre-coding can improve the advantage of PNC. It can do some processing before sending the information at the sender by use the channel state information. It can be effectively suppressed signal interference and reduces the complexity of the system at the receiver.Pre-coding research in recent years can be divided into linear and non-linear. Various signal space align schemes can effectively suppress mutual interference, and reduce the demand of the relay antennas.This paper presents a physical-layer network coding scheme with eigen-direction alignment pre-coding for multi-user MIMO-Y two-way relay channel. EDA scheme is applicable to situations of n_T?n_R, and the rotation matrix can improve the ill-conditioned channel matrix. The reduced-dimension EDA scheme is for the situations of RT nn ?,making EDA scheme can be applied more prevalent in our daily life. Through the channel assignment matrix design makes EDA scheme for the multi-user MIMO-Y two-way relay channel. And the chain coding makes the data transmission becoming safe. Finally,simulation and analysis of the program, shows that the scheme improves the decoding performance and sum-rates, and it enhances the confidentiality of the information.