@This paper proposes a new opportunistic scheduling scheme for hybrid network coding and cooperative relaying techniques in bidirectional communication networks. For 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 a higher throughput performance than CoR. However, the disadvantage of NC is that asymmetric traffic ratio conditions might cause a significant decrease in the total 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, the authors propose an opportunistic scheduling scheme for hybrid NC and CoR, assuming a three-node model including a single relaying node, in which the transmission protocol offering the best throughput performance can be adaptively selected by the scheduler in every transmission frame based on instantaneous channel state information. In the proposed scheduling scheme, a schedulerfs parameters can be adjusted to provide a tradeoff between the throughput and the bidirectional traffic ratio. In addition, this scheduling scheme is efficient without increasing the computational complexity compared to conventional algorithms. Computer simulation results reveal that the proposed scheduling scheme not only achieves higher throughput than conventional scheduling schemes but is also robust against asymmetric traffic ratio conditions. By adjusting the scheduler's parameters, in certain cases, it is possible to simultaneously maximize the throughput of NC and guarantee the offered traffic ratio.
@In summary, this paper proposes a novel adaptive resource scheduling robust to asymmetric bidirectional traffic assuming a three-node multihop network. The proposed idea of scheduling is flexible and believed to play an essential role in the further deployment of wireless distributed networks in the near future. |
Lin Shan
Hidekazu Murata
Sonia AISSA
Susumu Yoshida
