Location-Aware Cooperative Communications utilizing Linear Network Coding

Abstract

Cooperative communication can be used to reduce the transmit power of distant mobile units, compared to conventional direct transmission, given the same quality-of-service. However, imposing the constraint of having orthogonal transmission for the source and relays leads to large delay in TDMA systems. For a network of N mobile units, the transmission delay would be N(N +1)/2. In this work, we propose a location-aware cooperation-based scheme that aims to reduce transmit power of distant mobile units while maintaining a low transmission delay. The scheme utilizes a linear network coding protocol, where each mobile unit applies linear network coding to a set of transmit symbols that it has received previously. At the base station, multiuser detection is used to decouple the transmit symbols. Both decode-and-forward and amplify-and-forward cooperative protocols are considered. We show that our proposed scheme achieves a comparable bit-error-rate performance with the conventional cooperation-based TDMA scheme while requiring a delay of (2N - 1) time slots, a substantial reduction in the transmission delay.

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Document Details

Document Type
Technical Report
Publication Date
Jan 01, 2008
Accession Number
ADA487735

Entities

People

  • Ahmed S. Ibrahim
  • Hung-quoc Lai
  • K. J. Liu

Tags

DTIC Thesaurus Topics

  • Coding
  • Computer Programming
  • Computer Simulations
  • Cooperation
  • Cross Correlation
  • Decoding
  • Detection
  • Frequency Diversity
  • Multiple Access
  • Networks
  • Power Spectra
  • Probability Density Functions
  • Random Variables
  • Simulations
  • Symbols
  • Time Division Multiple Access
  • Wireless Networks

Fields of Study

  • Computer science

Readers

  • Computer Networking
  • Radio communications and signal processing.