Ls And QR Decompostion Channel Estimation Alagorithms for Mimo-OFDM Systems

Telecommunications in the current information age is increasingly relying on the wireless link. This is because wireless communication has made possible a variety of services ranging from voice to data and now to multimedia. Consequently, demand for new wireless capacity is growing rapidly at a very alarming rate. In a bid to cope with challenges of increasing demand for higher data rate, better quality of service, and higher network capacity, there is a migration from Single Input Single Output (SISO) antenna technology to a more promising Multiple Input Multiple Output (MIMO) antenna technology. On the other hand, Orthogonal Frequency Division Multiplexing (OFDM) technique has emerged as a very popular multi-carrier modulation technique to combat the problems associated with physical properties of the wireless channels such as multipath fading, dispersion, and interference. The combination of MIMO technology with OFDM techniques, known as MIMO-OFDM Systems, a major challenge in SISO-OFDM and MIMO-OFDM system is estimation of accurate channel state information (CSI) in order to make possible coherent detection of the transmitted signal at the receiver end of the system. In this paper, we propose iterative channel estimation based on QR Decomposition for MIMO OFDM systems. The aim of this paper is to investigate the effectiveness of QRD (QR decomposition) to reduce the computational complexity of channel estimation algorithms in MIMO-OFDM system, and design high performance channel estimation for this system by using iterative technique.