By Topic

Limited-Feedback-Based Adaptive Power Allocation and Subcarrier Pairing for OFDM DF Relay Networks With Diversity

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

2 Author(s)
Yong Liu ; Dept. of Electron. Eng., Shanghai Jiao Tong Univ., Shanghai, China ; Wen Chen

A limited-feedback-based dynamic resource allocation algorithm is proposed for a relay cooperative network with orthogonal frequency-division-multiplexing (OFDM) modulation. A communication model where one source node communicates with one destination node assisted by one half-duplex decode-and-forward (DF) relay is considered in this paper. We first consider the selective DF scheme, in which some relay subcarriers will keep idle if they do not have the advantage of forwarding the received symbols. Furthermore, we consider the enhanced DF scheme where the idle subcarriers are used to transmit new messages at the source. We aim to maximize the system's instantaneous rate by jointly optimizing power allocation and subcarrier pairing on each subcarrier based on the Lloyd algorithm. Both sum and individual power constraints are considered. The joint optimization turns out to be a mixed integer programming problem. We then transform it into a convex optimization by continuous relaxation and achieve the solution in the dual domain. The performance of the proposed joint resource allocation algorithm is verified by simulations. We find that the proposed scheme outperforms the existing methods in various channel conditions. We also observe that only a few feedback bits can achieve most of the performance gain of the perfect channel-state-information (CSI)-based resource allocation algorithm at different levels of signal-to-noise ratio (SNR).

Published in:

Vehicular Technology, IEEE Transactions on  (Volume:61 ,  Issue: 6 )