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: High Capacity Downlink Transmission with MIMO Interference Subspace Rejection in Multicellular CDMA Networks | EURASIP Journal on Applied Signal Processing 2004 5 707-726 2004 Hindawi Publishing Corporation High Capacity Downlink Transmission with MIMO Interference Subspace Rejection in Multicellular CDMA Networks Henrik Hansen INRS-Telecommunications Universite du Quebec Place Bonaventure 800 de la Gauchetiere Quest Suite 6900 Montreal Quebec Canada H5A 1K6 Email Sofiene Affes INRS-Telecommunications Universite du Quebec Place Bonaventure 800 de la Gauchetiere Quest Suite 6900 Montreal Quebec Canada H5A 1K6 Email affes@ Paul Mermelstein INRS-Telecommunications Universite du Quebec Place Bonaventure 800 de la Gauchetiere Quest Suite 6900 Montreal Quebec Canada H5A 1K6 Email mermel@ Received 31 December 2002 Revised 18 September 2003 We proposed recently a new technique for multiuser detection in CDMA networks denoted by interference subspace rejection ISR and evaluated its performance on the uplink. This paper extends its application to the downlink DL . On the DL the information about the interference is sparse for example spreading factor SF and modulation of interferers may not be known which makes the task much more challenging. We present three new ISR variants which require no prior knowledge of interfering users. The new solutions are applicable to MIMO systems and can accommodate any modulation coding SF and connection type. We propose a new code allocation scheme denoted by DACCA which significantly reduces the complexity of our solution at the receiving mobile. We present estimates of user capacities and data rates attainable under practically reasonable conditions regarding interferences identified and suppressed in a multicellular interference-limited system. We show that the system capacity increases linearly with the number of antennas despite the existence of interference. Our new DL multiuser receiver consistently provides an Erlang capacity gain of at least 3 dB over the single-user .
