Performance analysis of high speed downlink packet access system with space time coding on the rayleigh flat fading channel

Abstract

In recent years, in order to meet with the needs of the high data transmission many release of the next generation project standard reveals new technologies to improve data transmission capacity. Among them, multiple-input multiple-output (MIMO) system enhances the system capacity based on transmit and receive antenna diversity scheme. It offers a significant capacity gain over a traditional single-input single-output (SISO) system. Theoretically (4,4) MIMO system can give four times larger capacity than (1, 1) SISO system with no spectral resource increasing. MIMO systems generally fall into two categories, depending on the kind of gain they provide: spatial multiplexing methods yield capacity gain, while diversity methods yield link quality gain. This study selects a set of systems from each category, quantifying their gains analytically or via simulations, and shows how these improvements are dependent upon the specific block coding and the number of antennas. The capacity gain and the diversity gain are closely related with the number of antennas. The many reported cases recently studied are focused on the MIMO systems in which the number of receiving antennas is larger than that of transmit antennas. But the number of antennas in mobile terminal is rather limited in practical use. For example, the four antennas at the base station and the two antennas at the mobile terminal are more desirable requires. In this thesis, a basic concept of MIMO system, simple block codes (based on Orthogonal Space Time Block Code (OSTBC), Bell Labs Layered Space-Time Architecture (BLAST) and combining of them) and performance analysis of the High Speed Downlink Packet Access (HSDPA) used in Wideband Code Division Multiple Access (W-CDMA) system will be introduced. In conclusion it will be shown that the performance of HSDPA can be improves with MIMO systems. And furthermore, employing adaptive Space Time Block Code (STBC) can increases the overall throughput of the system.