MIMO-OFDM multiple access with variable amount of collision

Authors

Samuli Visuri and Helmut Bölcskei

Reference

Proc. of IEEE International Conference on Communications (ICC), Paris, France, pp. 286-291, June 2004

DOI: 10.1109/ICC.2004.1312496

[BibTeX, LaTeX, and HTML Reference]

Abstract

We consider frequency-selective Multiple-Input Multiple-Output (MIMO) multiple access fading channels with perfect channel knowledge in the receiver and no channel state information in the transmitters. Assuming that each of the users employs Orthogonal Frequency Division Multiplexing (OFDM), we introduce a multiple access scheme which allows to gradually vary the amount of user collision in signal space by assigning different subsets of the available OFDM tones to different users. The corresponding multiple access schemes range from FDMA (each OFDM tone is assigned to at most one user) to CDMA (each OFDM tone is assigned to all the users). We quantify the effect of signal space collision between the users by computing ergodic capacity regions for joint and single user decoding. In the case of joint decoding, we prove that irrespectively of the spatial receive fading correlation, the ergodic capacity region obtained by a fully collision-based scheme is an outer bound to any other OFDM-based multiple-access strategy, where the users collide only on subsets of the available tones. For single user decoding, we find that the amount of collision maximizing the capacity region depends critically on the number of transmit and receive antennas and the users' receive fading correlation.

Keywords

MIMO, OFDM, multiple access


Download this document:

 

Copyright Notice: © 2004 IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE.

This material is presented to ensure timely dissemination of scholarly and technical work. Copyright and all rights therein are retained by authors or by other copyright holders. All persons copying this information are expected to adhere to the terms and constraints invoked by each author's copyright. In most cases, these works may not be reposted without the explicit permission of the copyright holder.