Research Of The Spatial Multiplexing Issue In 60GHz Wireless Communication System

60GHz millimeter-wave wireless communication is a cutting-edge breakthrough technology in the field of short-range high-speed wireless transmission. With the rapid development of the multimedia technology and data storage technology, new applications require higher data transmission rate with Gbps level, and this demand will continue to rise in the near future.60GHz wireless communication technology brings possibilities to this demand and becomes the preferred technology to achieve short-range wireless communications with extremely low latency and high rate. It will bring us a new experience of transmission with very high speed, thus changing the way we live.In this paper, the spatial multiplexing issue in 60GHz wireless communication system is deeply studied based on the transmission characteristics of 60GHz signal and the related technologies, including the antenna array, the wireless personal area network and the existing channel access mechanism. Specific work involves the following aspects:First, a switching beamforming based 60GHz WPAN transmission model is established after serious research of the technical basis of spatial multiplexing in 60GHz communication system. And in order to solve the NLOS transmission problem of 60GHz links, a within network anti-blocking cooperative transmission model is designed based on the above network model. Second, for the purpose of spatial multiplexing, a STDMA based multi-user access mechanism is proposed, which is based on and also an improvement of the multi-user access mechanism in IEEE 802.15.3c standard. Third, a space-time multiplexing based link scheduling scheme is proposed. It takes full use of the high spatial multiplexing degree brought by 60GHz directional communication. Through simulations and analysis, it verifies that the proposed scheme can effectively enhance system throughput under the premise of ensuring a certain degree of fairness, thus further enhancing data transmission rate to meet the requirement of future supper high speed wireless applications. Fourth, on the basis of the above scheme, a space-time multiplexing based cooperative transmission scheme is proposed. This adaptive cooperation link scheduling algorithm can automatically detect link transmission situations and quickly switch to the cooperation mode if the LOS path of a certain link is blocked. In the cooperation mode, the optimal cooperative node will be selected. Meanwhile, concurrent transmission is conducted by link scheduling, thus achieving high system throughput at the same time when solving the NLOS transmission problem of 60GHz communication. At last, a within network multi-hop concurrent transmission scheme is proposed and analyzed under the premise that the system can provide accurate position information of nodes in the network. Higher data transmission rate is expected.