Study Of Decoding Algorithm And Performance Of The Combination Of STBC And V-BLAST In MIMO System

Tremendous changes are taking place in the Telecommunication network. The mobile communication market will keep a rapid growing tendency in the coming several years. The communication systems, no matter GSM, CDMA or the coming 3G mobile communication network, have been existing a very high request in the aspects of providing high quality,high speed rate, high dependability. How to make best use of the resource of frequency is the key point in the research of wireless communication. The technology of Multiple Input Multiple Output system can improve the capacity of communication system and the ratio of frequency spectrum without increasing any more bandwidth. It is the key technology that must be adopted in the new generation of the wireless communication system.This article emphasislly researches the new MIMO that combines the merits of STBC and V-BLAST. The paper mainly researches two respects: system performance and decoding algorithm. The quality of MIMO system will be assessed from transmission rate and dependability. Good encode structure and decoding algorithm can improve system performance.In performance, STBC-VBLAST system is analyzed from tow respects: capacity and spatial multiplexing gain. The capacity is important index of a system. Here, the capacity of STBC-VBLAST, STBC and VBLAST system is compare and analyzed by simulation. Spatial multiplexing of STBC-VBLAST, STBC and VBLAST system is derivative. Through comparing with each other, we can arrive at a conclusion that the system that STBC combines with V-BLAST can compromise between speed and dependability.In decoding algorithm, decoding of STBC-VBLAST system is investigated. A kind of typical STBC-VBLAST systems which has four transmit antennas is decoded. Two kinds of detection algorithms based on ZF criterion and group interference inhibiting algorithms at receiver. Compare and analyze the performance of several kinds of algorithms. Finally, the new code scheme is proposed according to the needs of reality. To this system frame, two detection algorithms are derived. Studies have suggested that the space-time code structure has better performance than STBC and V-BLAST. The new algorithm has better capability and is valued in the practical application.