By Topic

Multi-user adaptive receivers for a multiple-access system based on random permutations on time-varying frequency-selective channels with unknown delays and coefficients

Sign In

Cookies must be enabled to login.After enabling cookies , please use refresh or reload or ctrl+f5 on the browser for the login options.

Formats Non-Member Member
$33 $33
Learn how you can qualify for the best price for this item!
Become an IEEE Member or Subscribe to
IEEE Xplore for exclusive pricing!
close button

puzzle piece

IEEE membership options for an individual and IEEE Xplore subscriptions for an organization offer the most affordable access to essential journal articles, conference papers, standards, eBooks, and eLearning courses.

Learn more about:

IEEE membership

IEEE Xplore subscriptions

2 Author(s)
M. Coulon ; IRIT Lab., Univ. of Toulouse, Toulouse, France ; D. Roviras

This study deals with a multiple-access transmission scheme based on random permutations, which allows one to obtain both spectrum spreading and time spreading. In particular, one is interested by the multi-user detection when the transmission is achieved in the context of asynchronous frequency-selective and time-varying channels. For this detection, it is assumed that the channel coefficients and delays are unknown at the receiver side. Instead, only rough estimates of the minimum and maximum delays are available. However, it is supposed that the transmitter sends pilot signals, that is, training bit sequences, which allow the receiver to perform an LMS (least-mean-square)-type detection. This study provides theoretical performance results. Moreover, this random permutation-based transmission scheme is compared with the DS-CDMA system, for which a similar LMS receiver is defined, under the same assumptions. It is then shown that, for time-varying channels, the permutation-based system presents lower bit-error rates than the DS-CDMA system, since the former provides time diversity.

Published in:

IET Communications  (Volume:6 ,  Issue: 11 )