Analysis and scheduling of practical network coding in OFDMA relay networks
Author(s)
Author(s)
Xu, Y.
Lui, J. C. S.
Date Issued
2009
Publisher
Elsevier
Journal
Computer Networks
Volume
53
Issue
12
Start page
2120
End page
2139
Abstract
Network coding has become a prominent approach to improve throughput of wireless networks. However, most of work in the literature concentrates mainly on 802.11-like random access networks. New technologies such as OFDMA (orthogonal frequency division multiple access), offer new opportunities for employing network coding. This paper considers how to apply the practical network coding scheme in OFDMA relay networks via cross-layer optimization. Specifically, we aim to explore the following questions: (1) When and how can wireless nodes select relay paths in the presence of network coding? (2) How can an OFDMA relay system assign network resource such as subcarrier and power for all the transmitting nodes? (3) What are the impacts of OFDMA system parameters on the network coding gain? To answer these questions, two efficient coding-aware relay strategies are presented to select forwarding paths with fixed and dynamic power allocation. In order to exploit the network capacity in slow frequency selective fading channels, we formulate optimization frameworks and propose channel-aware coding-aware resource allocation algorithms for an arbitrary traffic pattern. Our studies show that the network coding (i.e. XOR) gain depends on the nodes’ powers, traffic patterns etc. Especially, OFDMA relay network with dynamic power possesses both coding gain and power gain. Extensive simulations are performed to verify our analysis and demonstrate the throughput improvement of our proposals in the presence of XOR coding.
SFU Affiliated Publication
No
Availability at SFU Library
No database links found.