Multiple-access interference-resistant acquisition for band-limited CDMA systems with random sequences
- 1 July 2000
- journal article
- Published by Institute of Electrical and Electronics Engineers (IEEE) in IEEE Journal on Selected Areas in Communications
- Vol. 18 (7) , 1203-1213
- https://doi.org/10.1109/49.857920
Abstract
The problem of estimating the propagation delay of a new user in a coded band-limited DS/CDMA system in the presence of multiple access interference (MAI) is considered. MAI-resistant acquisition schemes are developed for a general CDMA system without the constraint that the spreading sequences of the users repeat every symbol period. It is assumed that the spreading sequences and delays of the interfering users are known. However, knowledge of their amplitudes, which would need estimation, is not assumed, and their unreliable code-symbol estimates are not used. Under this scenario, acquisition schemes are derived based on the maximum-likelihood (ML) criterion. The performance of an approximation to the ML scheme is analyzed using Gaussian approximations and by assuming that the chip boundaries of the new user are known a priori. Simulations show that the analysis is reasonably accurate for parameters in the realm of practical interest.Keywords
This publication has 15 references indexed in Scilit:
- Synchronization of CDMA systems employing interference cancellationPublished by Institute of Electrical and Electronics Engineers (IEEE) ,2002
- The role of coding in CDMA systems with multiuser detectionPublished by Institute of Electrical and Electronics Engineers (IEEE) ,2002
- On chip-matched filtering and discrete sufficient statistics for asynchronous band-limited CDMA systemsIEEE Transactions on Communications, 2001
- Spectral efficiency of CDMA with random spreadingIEEE Transactions on Information Theory, 1999
- Maximum-likelihood synchronization of a single user for code-division multiple-access communication systemsIEEE Transactions on Communications, 1998
- Blind adaptive interference suppression for direct-sequence CDMAProceedings of the IEEE, 1998
- Blind adaptive interference suppression for the near-far resistant acquisition and demodulation of direct-sequence CDMA signalsIEEE Transactions on Signal Processing, 1997
- An efficient code-timing estimator for DS-CDMA signalsIEEE Transactions on Signal Processing, 1997
- A simple, accurate method to calculate spread-spectrum multiple-access error probabilitiesIEEE Transactions on Communications, 1992
- Near-far resistance of multiuser detectors in asynchronous channelsIEEE Transactions on Communications, 1990