Bit Loading Algorithms for Cooperative OFDM Systems

<p>Abstract</p> <p>We investigate the resource allocation problem for an OFDM cooperative network with a single source-destination pair and multiple relays. Assuming knowledge of the instantaneous channel gains for all links in the entire network, we propose several bit and power a...

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Bibliographic Details
Main Authors: Gui Bo, Cimini LeonardJ
Format: Article
Language:English
Published: SpringerOpen 2008-01-01
Series:EURASIP Journal on Wireless Communications and Networking
Online Access:http://jwcn.eurasipjournals.com/content/2008/476797
Description
Summary:<p>Abstract</p> <p>We investigate the resource allocation problem for an OFDM cooperative network with a single source-destination pair and multiple relays. Assuming knowledge of the instantaneous channel gains for all links in the entire network, we propose several bit and power allocation schemes aiming at minimizing the total transmission power under a target rate constraint. First, an optimal and efficient bit loading algorithm is proposed when the relay node uses the same subchannel to relay the information transmitted by the source node. To further improve the performance gain, subchannel permutation, in which the subchannels are reallocated at relay nodes, is considered. An optimal subchannel permutation algorithm is first proposed and then an efficient suboptimal algorithm is considered to achieve a better complexity-performance tradeoff. A distributed bit loading algorithm is also proposed for ad hoc networks. Simulation results show that significant performance gains can be achieved by the proposed bit loading algorithms, especially when subchannel permutation is employed.</p>
ISSN:1687-1472
1687-1499