This paper deals with the estimation of rapidly time-varying Rayleigh fading channels in synchronous multi-carrier direct-sequence code division multiple access (MC-DS-CDMA) systems. When the fading channel is approximated by an autoregressive (AR) process, it can be estimated by means of Kalman filtering for instance. Nevertheless, this requires the a priori estimation of the AR parameters. One standard solution consists in first fitting the AR process autocorrelation function to the Jakes one and then solving the resulting Yule-Walker equations (YWE). However, due to the band-limited nature of the Jakes Doppler spectrum, severely ill-conditioned ¥WE are unavoidable for all but very small AR model orders. Therefore, previous studies focused only on 1st and 2nd order AR models. To overcome the ill-conditioning problem, a very small positive bias can be added to the main diagonal of the autocorrelation matrix in the ¥WE. Even if the resulting process is not band-limited and corresponds to an AR process+noise model, the approximation can be of interest. Indeed, according to our simulation results, high-order AR models+noise yield significant results in terms of spectrum approximation and bit error rate (BER). However, to reduce the computational cost, a 5th order AR model can be considered.
1st Mosharaka International Conference on Mobile Computing and Wireless Communications (MIC-MCWC 2006)
Congress
2006 Global Congress on Mobile Computing and Wireless Communications (GC-MCWC 2006), 17-20 September 2006, Amman, Jordan
Pages
--1
Topics
Multicarrier Communication Systems Spread Spectrum for Fading Channels
ISSN
2227-331X
DOI
BibTeX
@inproceedings{178MCWC2006,
title={Estimation of MC-DS-CDMA fading channels based on Kalman filtering with high order autoregressive models},
author={Walid Hassasneh, and Ali A. Jamoos, and Eric Grivel, and Hanna I. Abdel Nour},
booktitle={2006 Global Congress on Mobile Computing and Wireless Communications (GC-MCWC 2006)},
year={2006},
pages={--1},
doi={}},
organization={Mosharaka for Research and Studies}
}