By Topic

Effect of mismatched SNR on the performance of log-MAP turbo detector

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
$31 $13
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

1 Author(s)
Khalighi, M.-A. ; Signal Process. Dept., Ecole Nat. Superieure de Telecommun., Paris, France

The effect of signal-to-noise ratio (SNR) mismatch on the bit error rate (BER) performance of log-MAP turbo detector is studied. It is shown that the sensitivity to the mismatched SNR depends on the channel loss and the encoder memory length. In particular, the sensitivity is more important for a "difficult-to-equalize" channel or, in other words, a high-loss channel. In fact, by affecting the equalizer and the decoder, a mismatched SNR (with an offset with respect to the true SNR) affects the convergence of the turbo detector. Using the asymptotic analysis tool of extrinsic information transfer (EXIT) charts, the effect of a positive or a negative SNR offset on the convergence of the log-MAP turbo detector is studied. When no information is available at the receiver on SNR, an online estimation of SNR is necessary in order to not lose the advantage of the log-MAP turbo detector over other suboptimal turbo detectors. In this view, a relatively simple SNR estimation method is proposed, which offers satisfying results.

Published in:

Vehicular Technology, IEEE Transactions on  (Volume:52 ,  Issue: 5 )