%0 Book Section %1 statphys23_0489 %A Takeda, K. %A Uda, S. %A Hatabu, A. %A Kabashima, Y. %B Abstract Book of the XXIII IUPAP International Conference on Statistical Physics %C Genova, Italy %D 2007 %E Pietronero, Luciano %E Loreto, Vittorio %E Zapperi, Stefano %K adaptive cdma matrix mimo random replica statphys23 tap topic-11 trick %T Statistical Mechanical Analysis of Random Vector Channel %U http://st23.statphys23.org/webservices/abstract/preview_pop.php?ID_PAPER=489 %X We investigate the performance of random vector channel in telecommunication systems, especially code division multiple access (CDMA) and multiple-input multiple-output (MIMO) schemes, which are core technologies used in modern wireless communication. Tanaka showed that the replica method of statistical mechanics enables accurate assessment of the communication performance of a basic CDMA model in which users' signature sequences are generated independently of each other in large system limit (EPL 54 (2001) 540). However, his scheme relies on the assumption of statistical independence among users' sequences and cannot be applied to systems of correlated sequences, which generally arise in optimizing communication performance. To examine such cases, we provide two approaches for handling correlated sequences based on the adaptive TAP approach proposed by Opper and Winther and random matrix theory. By these, we found that CDMA systems can be characterized by the eigenvalue spectrum of a cross-correlation matrix composed of signature sequences used in the communication. The utility of these approaches is shown by analyzing a system where generation of signature sequences is designed for enhancing orthogonality of the sequences, summary of which is shown in the figure below. We also investigate an advanced model of MIMO systems, which will be reported as well. (Part of the contents of this presentation was published in EPL 76 (2006) 1193.)

@incollection{statphys23_0489, abstract = {We investigate the performance of random vector channel in telecommunication systems, especially code division multiple access (CDMA) and multiple-input multiple-output (MIMO) schemes, which are core technologies used in modern wireless communication. Tanaka showed that the replica method of statistical mechanics enables accurate assessment of the communication performance of a basic CDMA model in which users' signature sequences are generated independently of each other in large system limit (EPL {\bf 54} (2001) 540). However, his scheme relies on the assumption of statistical independence among users' sequences and cannot be applied to systems of correlated sequences, which generally arise in optimizing communication performance. To examine such cases, we provide two approaches for handling correlated sequences based on the adaptive TAP approach proposed by Opper and Winther and random matrix theory. By these, we found that CDMA systems can be characterized by the eigenvalue spectrum of a cross-correlation matrix composed of signature sequences used in the communication. The utility of these approaches is shown by analyzing a system where generation of signature sequences is designed for enhancing orthogonality of the sequences, summary of which is shown in the figure below. We also investigate an advanced model of MIMO systems, which will be reported as well. (Part of the contents of this presentation was published in EPL {\bf 76} (2006) 1193.)}, added-at = {2007-06-20T10:16:09.000+0200}, address = {Genova, Italy}, author = {Takeda, K. and Uda, S. and Hatabu, A. and Kabashima, Y.}, biburl = {https://www.bibsonomy.org/bibtex/2a922f2d7b08bd64c59022a8ccb3862e5/statphys23}, booktitle = {Abstract Book of the XXIII IUPAP International Conference on Statistical Physics}, editor = {Pietronero, Luciano and Loreto, Vittorio and Zapperi, Stefano}, interhash = {eac1c79b543c9a44fb287c6d51a147fd}, intrahash = {a922f2d7b08bd64c59022a8ccb3862e5}, keywords = {adaptive cdma matrix mimo random replica statphys23 tap topic-11 trick}, month = {9-13 July}, timestamp = {2007-06-20T10:16:21.000+0200}, title = {Statistical Mechanical Analysis of Random Vector Channel}, url = {http://st23.statphys23.org/webservices/abstract/preview_pop.php?ID_PAPER=489}, year = 2007 }