Low Complexity Adaptive Hybrid MIMO Wireless System Based on QR Decomposition

• Main Authors: Chun-Kai Chen, 陳雋鎧
• Other Authors: 林丁丙
• Format: Others
• Language: en_US
• Published: 2008
• Online Access: http://ndltd.ncl.edu.tw/handle/ytcmgf

碩士 === 國立臺北科技大學 === 電腦與通訊研究所 === 96 === Adaptive hybrid Multiple-Input Multiple-Output (MIMO) system is a scheme of multi-antenna wireless communication. The receiver can feedback limited data to transmitter. Then, the transmitter utilizes different codes, power, and antenna allocation maximize the throughput under the different channel situation. Traditional adaptive systems enhance the throughput of the system by increasing the modulation orders. For the MIMO scheme, multi-antenna can provide the diversity gain and spatial multiplexing gain. An example of a pure diversity scheme is the SBTC while pure multiplexing scheme, like VBLAST, is concerned to get with spatial multiplexing gain. Their benefits can be revealed when working at the high SNR and low SNR separately. In this thesis, we utilize the hybrid source reallocation scheme to adapt the channel state instead of adjusting the modulation levels. Although hybrid schemes can enhance the performance effectively, receiver must increase the complexity significantly with multi-decoding algorithms. By using the QR decomposition, we can employ all decoder schemes into SIC algorithm. Furthermore, combining the characteristics of STBC codes such that the complexity of the receivers can be reduced.