Skip to main content

Bit Loading Algorithms for Cooperative OFDM Systems

Abstract

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.

Publisher note

To access the full article, please see PDF

Author information

Affiliations

Authors

Corresponding author

Correspondence to Bo Gui.

Rights and permissions

Open Access This article is distributed under the terms of the Creative Commons Attribution 2.0 International License (https://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Reprints and Permissions

About this article

Cite this article

Gui, B., Cimini, L.J. Bit Loading Algorithms for Cooperative OFDM Systems. J Wireless Com Network 2008, 476797 (2007). https://doi.org/10.1155/2008/476797

Download citation

Keywords

  • Power Allocation
  • Relay Node
  • Resource Allocation Problem
  • OFDM System
  • Power Allocation Scheme