Blind Adaptive Space-Time Receiving and Transmitting Diversities For Multiuser DS-CDMA Systems
نویسندگان
چکیده
Blind adaptive space-time processing techniques are developed for both uplink reception and downlink transmission in multiuser TDD DS-CDMA systems to overcome multipath fading effect and multiple access interference. The system consists of a spacetime array, a decorrelator, and a weight-adapter. For uplink reception, a hybrid combination of constant modulus algorithm and decisiondirected algorithm approach is employed for blind adaptation. For multi-input-multi-output channel estimation, minimum mean squared error estimation is made using respread sequences of the decision symbols as references. For downlink multiuser transmission, the generalized zero-forcing approach is developed for pre-equalization and pre-interference-cancellation.
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