Title :
Blind code timing and carrier offset estimation for DS-CDMA systems
Author :
Amleh, Khaled ; Li, Hongbin
Author_Institution :
Dept. of Electr. & Comput. Eng., Stevens Inst. of Technol., Hoboken, NJ, USA
Abstract :
In this paper we consider the problem of joint carrier offset and code timing estimation for CDMA (code division multiple access) systems. In contrast to most existing schemes which require multi-dimensional search over the parameter space, we propose a blind estimator that solves the joint estimation problem algebraically. By exploiting the noise subspace of the covariance matrix of the received data, the multiuser estimation is decoupled into parallel estimations of individual users, which makes computations efficient. The proposed estimator is non-iterative and near- far resistant. It can deal with frequency-selective and time-varying channels. The performance of the proposed scheme is illustrated by some computer simulations.
Keywords :
channel coding; channel estimation; code division multiple access; covariance matrices; spread spectrum communication; time-varying channels; timing; DS-CDMA systems; blind code timing; blind estimator; carrier offset estimation; code division multiple access; covariance matrix; frequency-selective channels; joint estimation problem; multidimensional search; multiuser estimation; parallel estimations; time-varying channels; Baseband; Frequency estimation; Frequency synchronization; Maximum likelihood estimation; Multiaccess communication; Multiple access interference; Space technology; Time-varying channels; Timing; Yield estimation;
Conference_Titel :
Multimedia and Expo, 2003. ICME '03. Proceedings. 2003 International Conference on
Print_ISBN :
0-7803-7965-9
DOI :
10.1109/ICME.2003.1221693