By Topic

Constellation design for decode-and-forward relay networks with adaptive modulation

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 $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

2 Author(s)
Dawei Zhao ; Communication Research Center, Harbin Institute of Technology, Harbin, P. R. China ; Honglin Zhao

In this paper, we consider constellation design for decode-and-forward relay networks with adaptive modulation, which improves the diversity combining gain by averaging over all transmission branches the bit reliability variations brought by multilevel modulation formats. A novel bit-error-rate expression for maximal ratio combining of M-ary Quadrature Amplitude Modulation (M-QAM) signals with different modulation levels is derived based on log-likelihood ratios and employed as the metric to optimize the respective constellation schemes for source and relay nodes. A heuristic algorithm with very low computational complexity is proposed as a suboptimal solution to this problem and its concept is demonstrated by analyzing the combining process of 8QAM and 64QAM signals. Computer simulations under AWGN and Rayleigh fading channels show that our proposed constellation scheme improves the diversity combining gain effectively at the expense of only a marginal implementation complexity increase.

Published in:

2012 IEEE 23rd International Symposium on Personal, Indoor and Mobile Radio Communications - (PIMRC)

Date of Conference:

9-12 Sept. 2012