Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: A Soft Detector with Good Performance/Complexity Trade-Off for a MIMO System | EURASIP Journal on Applied Signal Processing 2004 9 1266-1274 2004 Hindawi Publishing Corporation A Soft Detector with Good Performance Complexity Trade-Off for a MIMO System Jianhua Liu Department of Electrical and Computer Engineering University of Florida . Box 116130 Gainesville FL 32611-6130 USA Email jhliu@dsp. Jian Li Department of Electrical and Computer Engineering University of Florida . Box 116130 Gainesville FL 32611-6130 USA Email li@ Received 30 May 2003 Revised 23 November 2003 We present a hybrid soft detector that has a good performance complexity trade-off fora multiple-input multiple-output MIMO wireless communication system with known channel information. The new soft detector combines the merits of a simple unstructured least-squares LS -based soft detector and a list sphere decoder LSD -based soft detector for data bit detection. The former is computationally much more efficient than the latter at the cost of poorer performance. The poor performance of the former occurs mainly when the channel matrix is ill-conditioned. Whenever this happens we use the LSD-based soft detector in the hybrid soft detector otherwise we use the LS-based one. Moreover we provide a tight radius for a sphere decoder a hard detector via using the output of an LS-based hard detector. These two hard detectors are needed to determine if LS or LSD should be used in the hybrid soft detector. As an application example we consider doubling the maximum data rate of the IEEE conformable wireless local area networks by a MIMO system with two transmit and two receive antennas. For this application the new soft detector is about 10 times faster than the LSD-based one and is about 10 times slower than the LS-based one. Yet the packet error rate due to using the new soft detector is quite close to that of using the LSD-based one. Keywords and phrases BLAST MIMO soft detector convolutional codes OFDM WLAN. 1. INTRODUCTION High transmission data rate
