TY - JOUR
T1 - Blind channel estimation and detection for space-time coded CDMA in ISI channels
AU - Sun, Wei
AU - Li, Hongbin
PY - 2007/1
Y1 - 2007/1
N2 - In order to accommodate high data-rate applications, there is a significant interest in extending space-time (ST) coding, originally proposed for frequency-nonselective channels assumed known to the receiver, to unknown ISI (inter-symbol interference) channels. In this paper, we consider the problem of blind channel identification and linear multiuser receiver design for ST-coded CDMA (code-division multiple-access) systems operating in frequency-selective fading channels. We investigate the identifiability conditions and present a subspace-based blind channel estimator for such systems. To assess the performance of the proposed and other potential estimators, we derive an unconditional Cramér-Rao bound (CRB) which, similarly to the proposed blind channel estimator, does not assume the knowledge of the transmitted information symbols. We discuss various linear multiuser detection schemes that can be used in conjunction with the proposed channel estimator for symbol demodulation in ST-coded CDMA systems. Numerical examples are presented to illustrate the performance of the proposed channel estimator and linear detectors in multipath Rayleigh fading channels.
AB - In order to accommodate high data-rate applications, there is a significant interest in extending space-time (ST) coding, originally proposed for frequency-nonselective channels assumed known to the receiver, to unknown ISI (inter-symbol interference) channels. In this paper, we consider the problem of blind channel identification and linear multiuser receiver design for ST-coded CDMA (code-division multiple-access) systems operating in frequency-selective fading channels. We investigate the identifiability conditions and present a subspace-based blind channel estimator for such systems. To assess the performance of the proposed and other potential estimators, we derive an unconditional Cramér-Rao bound (CRB) which, similarly to the proposed blind channel estimator, does not assume the knowledge of the transmitted information symbols. We discuss various linear multiuser detection schemes that can be used in conjunction with the proposed channel estimator for symbol demodulation in ST-coded CDMA systems. Numerical examples are presented to illustrate the performance of the proposed channel estimator and linear detectors in multipath Rayleigh fading channels.
KW - Blind channel identification
KW - Cramér-Rao bound
KW - Multiuser detection
KW - Space-time coding
KW - Transmit diversity
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U2 - 10.1016/j.dsp.2004.04.004
DO - 10.1016/j.dsp.2004.04.004
M3 - Article
AN - SCOPUS:37849186252
SN - 1051-2004
VL - 17
SP - 280
EP - 296
JO - Digital Signal Processing: A Review Journal
JF - Digital Signal Processing: A Review Journal
IS - 1
ER -