Evaluation of Analog Joint Source-Channel Coding Systems for Multiple Access Channels

© 2015 IEEE. This version of the article has been accepted for publication, after peer review. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works. The Version of Record is available online at: https://doi.org/10.1109/TCOMM.2015.2427164[Abstract]: We address the evaluation of low-complexity analog Joint Source Channel Coding (JSCC) methods for the transmission of discrete-time analog symbols over Multiple-Input Multiple-Output (MIMO) Multiple Access Channels (MAC). Analog JSCC is employed to encode the source information at each transmitter prior to be directly input to the MAC access scheme. Three channel access methods are considered to ensure the receiver is able to recover the user information: Code Division Multiple Access (CDMA), linear MMSE access codes and opportunistic access. CDMA allows the orthogonal transmission of the user data requiring only Channel State Information (CSI) at reception. On the other hand, linear MMSE access codes exploit CSI knowledge at transmission and exhibit better performance. Finally, opportunistic access also exploits CSI at transmission and allocates all MAC resources to the user with the strongest channel. This latter access scheme exhibits the best performance in terms of sum distortion although it may lead to unfair rate distributions among users.This work has been funded by Xunta de Galicia, Ministerio de Economía y Competitividad of Spain, and FEDER funds of the European Union under grants 2012/287, TEC2010-19545-C04-01, CSD2008-00010 and TEC2013-47141-C4-1-R. This work has also been supported in part by NSF Award CIF- 0915800 and by the Air Force Research Laboratory under agreement number FA9550-12-1-0086.Xunta de Galicia; CN 2012/287United States. National Science Foundation; CIF- 0915800United States. Air Force Research Laboratory; FA9550-12-1-008

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