Study On Space-Time Coding Technology In Block Fading Channel

Because of the time variation, the transmission characteristics of wireless channel changes continuously with time. However, when there is no relative movement between the base station and the mobile station, the channel keeps unchanged for a certain period of time. And all the continuous symbols during this period suffer from the same fading, which is called Block Fading Model.Multiple Input Multiple Output (MIMO) technology is a great breakthrough in wireless mobile communications, and it has become a key technology for the new generation of mobile communication systems. The Bell Lab Layered Space-Time Code (BLAST) is just based on this technology. With the properties of higher data rate and better link reliability, BLAST has now been interested by researchers all over the world. This paper studies on the structure of V-BLAST and Turbo-BLAST including their corresponding detection algorithm based on the Block Fading Model.As the represent of the BLAST structure at present, V-BLAST, with largest data transmission capabilities, has been adopted by 3GPP standard etc. and is also quite interested by researchers. This paper analyzes of the original detection algorithm of V-BLAST, and proposes an improved iterative detection algorithm by using the QR decomposition scheme. Our new algorithm improves the detection performance of the V-BLAST system.In D-BLAST, the transmission data has been seriously affected because of the boundary wastage. V-BLAST overcomes this defect, but it still does not utilize the technology of transmit diversity. Turbo-BLAST makes use of the iterative detection technology of Turbo and improves the space-time structure of D-BLAST along with transmission rate and bit error rate. This paper improves the space-time structure and detection model of Turbo-BLAST. The simulation results show that the new scheme has good performance.