Title :
A symbol-by-symbol multiuser detector with joint amplitude and delay estimation
Author :
Iltis, Ronald A. ; Mailaender, Laurence
Author_Institution :
Dept. of Electr. & Comput. Eng., California Univ., Santa Barbara, CA, USA
Abstract :
A multiuser detector is developed for code-division multiple access applications, in which the delays and amplitudes of the incoming waveforms are estimated recursively. The overall algorithm is an approximation to the symbol-by-symbol detector of K. Abend and B. Fritchman (1970), in which the likelihoods are computed using extended Kalman filter (EKF) innovations. The EKF provides, in addition to the likelihoods, joint estimates of the signal delays and amplitudes. The resulting algorithm is quite complex, due to the large number of possible composite symbols corresponding to the multiple users. However, it is shown that the likelihood computation and EKF updates can be expressed in terms of a set of cross-correlation functions, which need only be computed for a subset of the possible symbols. Thus, the algorithm may be practical for certain narrowband applications using programmable DSP device implementations
Keywords :
Kalman filters; code division multiple access; delays; filtering and prediction theory; parameter estimation; signal detection; CDMA; amplitude estimation; code-division multiple access; cross-correlation functions; delay estimation; extended Kalman filter; likelihood computation; narrowband applications; programmable DSP device; signal delays; symbol-by-symbol multiuser detector; Amplitude estimation; Approximation algorithms; Delay estimation; Detectors; Digital signal processing; Multiaccess communication; Narrowband; Propagation delay; Recursive estimation; Technological innovation;
Conference_Titel :
Signals, Systems and Computers, 1992. 1992 Conference Record of The Twenty-Sixth Asilomar Conference on
Conference_Location :
Pacific Grove, CA
Print_ISBN :
0-8186-3160-0
DOI :
10.1109/ACSSC.1992.269248
