Opportunistic Scheduling for Hybrid Network Coding and Cooperative Relaying Techniques in Wireless Networks

Lin SHAN  Hidekazu MURATA  Sonia AISSA  Susumu YOSHIDA  

IEICE TRANSACTIONS on Communications   Vol.E95-B    No.5    pp.1751-1760
Publication Date: 2012/05/01
Online ISSN: 1745-1345
DOI: 10.1587/transcom.E95.B.1751
Print ISSN: 0916-8516
Type of Manuscript: PAPER
Category: Wireless Communication Technologies
cooperative relaying,  network coding,  opportunistic scheduling,  asymmetric traffic,  

Full Text: FreePDF

With the purpose of improving the performance of next generation wireless networks, cooperative relaying (CoR) and network coding (NC) are promising techniques. The number of time slots required for NC in bidirectional transmission is less than that required for CoR, and hence, NC can achieve higher throughput performance than CoR. However, the disadvantage of NC is that asymmetric traffic ratio conditions might cause a significant decrease in the bidirectional throughput. In contrast, CoR is robust to asymmetric traffic ratio conditions. In this paper, in order to improve the throughput of NC even under asymmetric traffic ratio conditions, we propose an opportunistic scheduling scheme for hybrid NC and CoR. In the proposed scheduling scheme, the transmission protocol with best throughput performance can be adaptively selected based on instantaneous channel state information. Computer simulation results reveal that the proposed scheduling scheme not only achieve higher throughput than the conventional scheduling scheme but is also robust against asymmetric traffic ratio conditions. By adjusting the scheduler's parameter, the proposed scheduling scheme can provide a tradeoff between the throughput and the traffic ratio. Moreover, in certain cases, maximizing the throughput of NC and guaranteeing the offered traffic ratio can be achieved at the same time.