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Hybrid Pre-coded ST-BC MIMO-CDMA System with Semi-blind Channel EstimationLiao, Chong-Zhih 30 August 2011 (has links)
In this thesis, a novel pre-coded direct-sequence code division multiple access (DS-CDMA) associated with the multiple-input multiple-output (MIMO) antennas, along with Alamouti¡¦s space-time block code (ST-BC) is considered. In the transmitter, the idea of hybrid pre-coded is exploited; it can be employed to counteract the inter-symbol interference (ISI) introduced by the channel fading duo to multipath propagation, and can be used to exacting the full information of channel impulse response (CIR) in the receiver for semi-blind channel estimation. Under this transceiver framework, we develop a semi-blind adaptive MIMO-CDMA receiver, based on the linearly constrained constant modulus (LCCM) criterion, for symbol recovery. Furthermore, to reduce the complexity of receiver design, the framework of the generalized sidelobe canceller (GSC) associated with the recursive least-squares (RLS) algorithm is adopted, and the gradient approach is applied to track the desired user¡¦s amplitude, simultaneously, and is named as the GSC-CM-IQRD-RLS algorithm. Via computer simulations, the superior performance and the advantages of proposed scheme is verified; it outperforms the conventional LCMV-based algorithm, and slightly better than the convention CM-GSC-RLS receiver, with the paid of spectral efficient.
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Novel Blind ST-BC MIMO-CDMA Receiver with Adaptive Constant Modulus-GSC-RLS Algorithm in Multipath ChannelCheng, Ming-Kai 18 August 2009 (has links)
In this thesis, we present a new hybrid pre-coded direct-sequence code division multiple access (DS-CDMA) system framework that use the multiple-input multiple-output (MIMO) antennas along with Alamouti¡¦s space-time block code (ST-BC). In the transmitter, the idea of hybrid pre-coded is exploited. It not only used to counteract the inter-symbol interference (ISI) introduced by the channel fading duo to multipath propagation but also very useful for exacting the phase of channel by appropriate design, which is not adopted in the conventional blind receiver. Under this structure, we propose a new blind adaptive MIMO-CDMA receiver based on the linearly constrained constant modulus (LCCM) criterion. To reduce the complexity of receiver design, framework of the generalized sidelobe canceller (GSC) associated with the recursive least square (RLS) algorithm is adopted for implementing the LCCM MIMO-CDMA receiver, and use gradient method to track the desired user¡¦s amplitude, simultaneously. Via computer simulations, advantages of the proposed scheme will be verified. Compared to the conventional blind Capon receiver, we will show that the performance of the proposed scheme is more robust against inaccuracies in the acquisition of the desired user¡¦s timing.
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