基于物理干扰模型的分布式传输调度算法

Distributed link scheduling algorithm with a physical interference model

传统上对无线多跳网络中传输调度问题的研究是基于协议干扰模型的。该模型对问题的分析比较简单,通常会使调度算法的性能较差。该文提出了一种基于物理干扰模型的分布式调度算法来提高网络吞吐量。物理干扰模型反映了接收节点的信干噪比(SINR),是对现实场景中干扰的一种更精确的抽象。该文将传输调度问题建模为整数线性规划(ILP)问题,然后将其松弛为一般的线性规划(LP)问题,提出一种分布式算法来求解LP问题的最优解,进而计算传输调度问题的最优解。在该分布式算法中,每个节点只需要本地的信道信息便可以计算出最优的传输概率,从而实现最优调度。仿真结果表明:该算法可以很快收敛到最优解,并且吞吐量性能与中心式算法接近。

Traditional studies of link scheduling in wireless multi-hop networks have been based on the protocol interference model. This model facilitates problem analysis, but usually gives poor performance because of its simplicity. This paper presents a distributed link scheduling algorithm with a physical interference model to increase network throughput. The physical interference model reflects the aggregated signal to interference and noise ratio （SINR）, which is a more accurate abstraction of the real conditions. This paper formulates the link scheduling problem as an integer linear programming （ILP） problem, and relaxes it to a linear programming （LP） problem. The optimal LP solution is given with a distributed algorithm to compute the optimal solution. In the distributed algorithm, each node can compute the optimal transmission probability using only local channel information for the optimal scheduling. Simulations show that the algorithm quickly converges to the optimal solution and provides good throughput performance compared with a centralized algorithm.