The original paper is in English. Non-English content has been machine-translated and may contain typographical errors or mistranslations. ex. Some numerals are expressed as "XNUMX".
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The original paper is in English. Non-English content has been machine-translated and may contain typographical errors or mistranslations. Copyrights notice
Une version modifiée de l'algorithme SAGE est présentée pour l'estimation conjointe des paramètres de retard-azimut-atténuation dans un système DS-CDMA multi-utilisateur. La modification introduite consiste à utiliser différentes longueurs d'intervalle de temps lors du calcul des corrélations temporelles pour optimiser les différents paramètres du canal. Cette modification a été proposée dans le but de réduire davantage le poids de calcul de l'algorithme en cas de réception d'ondes suffisamment résolubles. Plus précisément, nous avons constaté que des fenêtres à intervalles courts sont suffisantes pour estimer les retards et les angles d’azimut, ce qui est très efficace pour réduire la charge de calcul dans leurs processus d’optimisation. Quant à l'estimation des paramètres d'atténuation, une fenêtre temporelle plus longue, égale à la longueur du préambule, est considérée pour une estimation plus précise. Deux autres estimateurs sont également proposés. Le premier combine le SAGE modifié avec une estimation séquentielle des paramètres d'atténuation, adaptée aux canaux à variation lente. Un autre, similaire au premier, et principalement conçu pour atténuer l’influence des puissants interféreurs actuels. A travers un exemple numérique, les performances des trois schémas d'estimation présentés, en termes de résistance proche-éloignée, sont comparées. Et il est démontré que le deuxième estimateur combiné proposé surpasse le SAGE modifié dans des environnements avec des niveaux de MAI élevés.
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Youssef R. SENHAJI, Takaya YAMAZATO, Masaaki KATAYAMA, Akira OGAWA, "Joint Multi-Dimensional Channel Parameter Estimation Schemes for DS-CDMA Systems Using a Modified Version of the SAGE Algorithm" in IEICE TRANSACTIONS on Communications,
vol. E84-B, no. 3, pp. 511-519, March 2001, doi: .
Abstract: A modified version of the SAGE algorithm is presented for joint delay-azimuth-attenuation parameters' estimation in a multiuser DS-CDMA system. The introduced modification consists of using different time interval lengths when calculating the time correlations for optimizing the different channel parameters. This modification was proposed for the purpose of a further reduction in the algorithm's computational weight in case of receiving sufficiently resolvable waves. Specifically, we found that short interval windows are sufficient for estimating delays and azimuth angles, which is quite effective in reducing the computational burden in their optimization processes. As for the estimation of the attenuation parameters, a longer time window, equal to the preamble length, is considered for more accurate estimation. Also two other estimators are proposed. The first one combining the modified SAGE with a sequential estimation of the attenuation parameters, suitable for slowly varying channels. Another one, similar to the first, and primarily designed to alleviate the influence of present strong interferers. Through a numerical example, the performances of the three presented estimation schemes, in terms of their near-far resistance, are compared. And it is shown that the proposed second combined estimator outperforms the modified SAGE in environments with high MAI levels.
URL: https://global.ieice.org/en_transactions/communications/10.1587/e84-b_3_511/_p
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@ARTICLE{e84-b_3_511,
author={Youssef R. SENHAJI, Takaya YAMAZATO, Masaaki KATAYAMA, Akira OGAWA, },
journal={IEICE TRANSACTIONS on Communications},
title={Joint Multi-Dimensional Channel Parameter Estimation Schemes for DS-CDMA Systems Using a Modified Version of the SAGE Algorithm},
year={2001},
volume={E84-B},
number={3},
pages={511-519},
abstract={A modified version of the SAGE algorithm is presented for joint delay-azimuth-attenuation parameters' estimation in a multiuser DS-CDMA system. The introduced modification consists of using different time interval lengths when calculating the time correlations for optimizing the different channel parameters. This modification was proposed for the purpose of a further reduction in the algorithm's computational weight in case of receiving sufficiently resolvable waves. Specifically, we found that short interval windows are sufficient for estimating delays and azimuth angles, which is quite effective in reducing the computational burden in their optimization processes. As for the estimation of the attenuation parameters, a longer time window, equal to the preamble length, is considered for more accurate estimation. Also two other estimators are proposed. The first one combining the modified SAGE with a sequential estimation of the attenuation parameters, suitable for slowly varying channels. Another one, similar to the first, and primarily designed to alleviate the influence of present strong interferers. Through a numerical example, the performances of the three presented estimation schemes, in terms of their near-far resistance, are compared. And it is shown that the proposed second combined estimator outperforms the modified SAGE in environments with high MAI levels.},
keywords={},
doi={},
ISSN={},
month={March},}
Copier
TY - JOUR
TI - Joint Multi-Dimensional Channel Parameter Estimation Schemes for DS-CDMA Systems Using a Modified Version of the SAGE Algorithm
T2 - IEICE TRANSACTIONS on Communications
SP - 511
EP - 519
AU - Youssef R. SENHAJI
AU - Takaya YAMAZATO
AU - Masaaki KATAYAMA
AU - Akira OGAWA
PY - 2001
DO -
JO - IEICE TRANSACTIONS on Communications
SN -
VL - E84-B
IS - 3
JA - IEICE TRANSACTIONS on Communications
Y1 - March 2001
AB - A modified version of the SAGE algorithm is presented for joint delay-azimuth-attenuation parameters' estimation in a multiuser DS-CDMA system. The introduced modification consists of using different time interval lengths when calculating the time correlations for optimizing the different channel parameters. This modification was proposed for the purpose of a further reduction in the algorithm's computational weight in case of receiving sufficiently resolvable waves. Specifically, we found that short interval windows are sufficient for estimating delays and azimuth angles, which is quite effective in reducing the computational burden in their optimization processes. As for the estimation of the attenuation parameters, a longer time window, equal to the preamble length, is considered for more accurate estimation. Also two other estimators are proposed. The first one combining the modified SAGE with a sequential estimation of the attenuation parameters, suitable for slowly varying channels. Another one, similar to the first, and primarily designed to alleviate the influence of present strong interferers. Through a numerical example, the performances of the three presented estimation schemes, in terms of their near-far resistance, are compared. And it is shown that the proposed second combined estimator outperforms the modified SAGE in environments with high MAI levels.
ER -