Teng Joon Lim 8 Form 101 – Application for a Grant Part Ii 1 Recent Progress in Research 1.1 Multiuser Receiver Design
نویسنده
چکیده
The joint detection of multiple signal streams, usually transmitted using code division multiple access (CDMA), can give much better performance than conventional matched-filter methods. Receivers designed using this idea are generically known as multiuser detectors. Our work in this area has included the development of a recursive chip-rate detector that gives linear minimum mean squared error (MMSE) performance even in asynchronous channels [1, 2, 3]. The rigorous explanation of how a Kalman filter, and not the commonly used tapped delay line, gives LMMSE estimates is offered in [4]. CDMA detectors based on the least mean square (LMS) adaptive filter have also been studied. A strict convergence analysis, revealing some interesting and previously unknown results, is given in [5]. An adaptive infinite impulse response (IIR) filter for CDMA detection was introduced in [6]. This structure was suggested by the recursive form of the Kalman filter, which was shown in [4] to be optimal for a given delay in an asynchronous system. Various aspects of blind adaptive detection were investigated in [7, 8]. Multistage interference cancellation for CDMA is another area which we have successfully studied. Contributions include the matrix representation of linear multistage detectors [9, 10, 11]; implementation aspects of multistage ICs [12, 13, 14, 15]; and links between multistage non-linear IC and constrained maximum likelihood (ML) estimation [16].
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