Collaborative Communication Used In Wireless Communications Technology Research

With the rapid development of wireless communication, MIMO technology was put forward to solve many problems of wireless communication, but it has many constraints. Cooperative communication overcomes the physical limitation of MIMO acting as the virtual multiple antenna system, which can achieve performance and technical requirements. This paper is divided into two aspects, cooperative communication is applicated in deep space communications and LTE system, and we respectively study and analyze coding and channel estimation techniques.Deep space communication has the special transmission environment. Because of long distance transmission the transmission error rate is high. Power consumption and long transmission delay are also key problems to the deep space communication. Channel coding is an effective method to improve performance. Fountain code can achieve reliable and efficient transmission without retransmission system, which is suitable for application in deep space. In this paper we analyze the cooperative communication technology of fountain code in the deep space and introduce the coding process of fountain codes in deep space transmission models based on collaborative distributed fountain coding. Then simulations of the fountain codes are performed under the model of two sources and one relay node. The results show that fountain codes are a good properties code.In LTE-Advanced, to improve the performance of users which are on the edge of the cell, CoMP technologie is put forward. CoMP technology is the special case of collaborative communication technology, which can improve the throughput of coverage and the performance of entire system. The channel's information estimation is very important in CoMP system. Therefore, this article mainly discusses the design of CoMP downlink reference signals including DM-RS and CSI-RS pattern. Several design patterns and the adaptive pilot patterns are put forward.