Applied Research On Differential Space-Time Coding Technology

Space-time coding technology is based on multi-elements antenna array and has strong points of both time processing and space processing. It can satisfy the requirements of high data rate transmission in the future radio mobile system without the increase of the transmitting power and the spread of the frequency. And it can greatly improve the quality of communication services and system capacity under fading channels.Differential space-time coding is suitable for the future 3G\4G mobile communication under rapid fading channels. Compared with other space-time coding technologies, it can obtain well performance without perfect channel state information (CSI). In this dissertation, we look forward to improve the performance of the differential space-time system by concatenating it with an outer code and using iterative soft-decision decoding algorithm. After detailed analyses and simulations, some positive results are obtained and summarized as follow:Firstly, the different space-time encoding technologies were briefly introduced.Secondly, the encoding and decoding principle of three different bland space-time modulations is presented. Then several existing schemes of bland space-time codes are analyzed and compared, the essence of coding and the connection between these existing schemes is disclosed and the simulation results are given.Lastly, the system structure of the serially concatenated differential space-time codes is presented. The iterative soft-decision decoding algorithm for the system was introduced. The simulation result of the differential space-time modulation concatenated with LDPC code is given, then the advantages and limitations of the algorithm are pointed out.