Multiple access interferecnce (MAI) is a major factor limiting the performance of direct-sequence code-division multiple access (DS-CDMA) systems. Since the amount of MAI is dependent on the correlation among user signals, one way to reduce it is to reduce such correlation. In mobile multiuser communication, each user experiences a different time-varying channel response. This user-dependent characteristic in channel variation can be exploited to assist the separation of different user signals, in addition to the capability provided by the spreading codes. As the correlation among different user channels are expected to decrease with increase in time span, enhanced decorrelation among different users' signals can be effected by spacing out the chips of one modulated symbol in time. Thus we consider chip-interleaving DS-CDMA (CI-DS-CDMA) in this study. We investigate its performance through theoretical analysis and computer simulation. Employing only a slightly modified rake receiver structure, CI-DS-CDMA is shown to attain significant performance gain over conventional DS-CDMA, in multiple access communication over single- and multi-path fading channels, without complicated multiuser detection. CI-DS-CDMA also has a lower demand for short-term power control than conventional DS-CDMA, especially in one-path Rayleigh fading. Results of the theoretical analysis and the computer simulation agree well with each other.
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Yu-Nan LIN, David W. LIN, "Multiple Access over Fading Multipath Channels Employing Chip-Interleaving Code-Division Direct-Sequence Spread Spectrum" in IEICE TRANSACTIONS on Communications,
vol. E86-B, no. 1, pp. 114-121, January 2003, doi: .
Abstract: Multiple access interferecnce (MAI) is a major factor limiting the performance of direct-sequence code-division multiple access (DS-CDMA) systems. Since the amount of MAI is dependent on the correlation among user signals, one way to reduce it is to reduce such correlation. In mobile multiuser communication, each user experiences a different time-varying channel response. This user-dependent characteristic in channel variation can be exploited to assist the separation of different user signals, in addition to the capability provided by the spreading codes. As the correlation among different user channels are expected to decrease with increase in time span, enhanced decorrelation among different users' signals can be effected by spacing out the chips of one modulated symbol in time. Thus we consider chip-interleaving DS-CDMA (CI-DS-CDMA) in this study. We investigate its performance through theoretical analysis and computer simulation. Employing only a slightly modified rake receiver structure, CI-DS-CDMA is shown to attain significant performance gain over conventional DS-CDMA, in multiple access communication over single- and multi-path fading channels, without complicated multiuser detection. CI-DS-CDMA also has a lower demand for short-term power control than conventional DS-CDMA, especially in one-path Rayleigh fading. Results of the theoretical analysis and the computer simulation agree well with each other.
URL: https://global.ieice.org/en_transactions/communications/10.1587/e86-b_1_114/_p
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@ARTICLE{e86-b_1_114,
author={Yu-Nan LIN, David W. LIN, },
journal={IEICE TRANSACTIONS on Communications},
title={Multiple Access over Fading Multipath Channels Employing Chip-Interleaving Code-Division Direct-Sequence Spread Spectrum},
year={2003},
volume={E86-B},
number={1},
pages={114-121},
abstract={Multiple access interferecnce (MAI) is a major factor limiting the performance of direct-sequence code-division multiple access (DS-CDMA) systems. Since the amount of MAI is dependent on the correlation among user signals, one way to reduce it is to reduce such correlation. In mobile multiuser communication, each user experiences a different time-varying channel response. This user-dependent characteristic in channel variation can be exploited to assist the separation of different user signals, in addition to the capability provided by the spreading codes. As the correlation among different user channels are expected to decrease with increase in time span, enhanced decorrelation among different users' signals can be effected by spacing out the chips of one modulated symbol in time. Thus we consider chip-interleaving DS-CDMA (CI-DS-CDMA) in this study. We investigate its performance through theoretical analysis and computer simulation. Employing only a slightly modified rake receiver structure, CI-DS-CDMA is shown to attain significant performance gain over conventional DS-CDMA, in multiple access communication over single- and multi-path fading channels, without complicated multiuser detection. CI-DS-CDMA also has a lower demand for short-term power control than conventional DS-CDMA, especially in one-path Rayleigh fading. Results of the theoretical analysis and the computer simulation agree well with each other.},
keywords={},
doi={},
ISSN={},
month={January},}
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TY - JOUR
TI - Multiple Access over Fading Multipath Channels Employing Chip-Interleaving Code-Division Direct-Sequence Spread Spectrum
T2 - IEICE TRANSACTIONS on Communications
SP - 114
EP - 121
AU - Yu-Nan LIN
AU - David W. LIN
PY - 2003
DO -
JO - IEICE TRANSACTIONS on Communications
SN -
VL - E86-B
IS - 1
JA - IEICE TRANSACTIONS on Communications
Y1 - January 2003
AB - Multiple access interferecnce (MAI) is a major factor limiting the performance of direct-sequence code-division multiple access (DS-CDMA) systems. Since the amount of MAI is dependent on the correlation among user signals, one way to reduce it is to reduce such correlation. In mobile multiuser communication, each user experiences a different time-varying channel response. This user-dependent characteristic in channel variation can be exploited to assist the separation of different user signals, in addition to the capability provided by the spreading codes. As the correlation among different user channels are expected to decrease with increase in time span, enhanced decorrelation among different users' signals can be effected by spacing out the chips of one modulated symbol in time. Thus we consider chip-interleaving DS-CDMA (CI-DS-CDMA) in this study. We investigate its performance through theoretical analysis and computer simulation. Employing only a slightly modified rake receiver structure, CI-DS-CDMA is shown to attain significant performance gain over conventional DS-CDMA, in multiple access communication over single- and multi-path fading channels, without complicated multiuser detection. CI-DS-CDMA also has a lower demand for short-term power control than conventional DS-CDMA, especially in one-path Rayleigh fading. Results of the theoretical analysis and the computer simulation agree well with each other.
ER -