Title :
On channel parameter estimation in a space-time bit-interleaved-coded modulation system for multipath DS-CDMA uplink with receive diversity
Author :
Guenach, Mamoun ; Wymeersch, Henk ; Moeneclaey, Marc
Author_Institution :
Dept. of Telecommun. & Inf. Process., Ghent Univ., Gent, Belgium
Abstract :
In this paper, we consider iterative space-time multiuser detection and channel parameter estimation in a bit-interleaved coded modulation scheme for asynchronous direct-sequence code division multiple access (DS-CDMA) transmission over frequency selective, slowly fading channels. Accurate estimation of the channel parameters is critical as it has great impact on the overall BER performance. We present an iterative space-time multiuser (STMU) turbo detection and estimation scheme, based on space alternating generalized expectation maximization (SAGE) algorithm. This algorithm operates on the coded symbols by exchanging soft information between the detector and the estimator. We show through computer simulations that the proposed low complexity STMU receiver considerably outperforms conventional estimation schemes and achieves excellent performance, both in terms of BER and estimation error variance. Finally, we will consider different mapping strategies and investigate their impact on the performance and complexity of the estimator.
Keywords :
channel estimation; code division multiple access; diversity reception; error statistics; fading channels; interleaved codes; modulation coding; multipath channels; multiuser detection; radio links; space-time codes; spread spectrum communication; BER performance; asynchronous direct-sequence code division multiple access; channel parameter estimation; computer simulations; estimation error variance; fading channels; frequency selective channels; information exchange; iterative space-time multiuser detection; mapping strategy; multipath DS-CDMA uplink; receive diversity; space-time bit-interleaved-coded modulation system; Bit error rate; Fading; Frequency conversion; Frequency estimation; Interleaved codes; Iterative algorithms; Modulation coding; Multiaccess communication; Multiuser detection; Parameter estimation; Code-aided; estimation; iterative processing; synchronization;
Journal_Title :
Vehicular Technology, IEEE Transactions on
DOI :
10.1109/TVT.2005.853458