传感器网络中提高吞吐量的机会波束调度算法

Opportunistic Beamforming Scheduling Algorithm for Improving the SNR and Communication Rate of Wireless Sensor Networks

无线传播环境会影响传感器网络的信息传输质量,为了提高通信时信噪比和系统的通信速率,该文采用一种机会调度算法来有效地调度信道状态较好的传感器节点。中心节点采用多天线阵列,传感器节点采用单天线以节省功率和体积,通信分为两个阶段,导频阶段,多天线阵列随机生成酉波束;波束选择阶段,传感器节点接收导频信息后根据预设的阈值判断是否进入通信状态进而选择相应的随机波束。实验表明,机会调度算法可以有效地提高系统的通信速率。

Wireless broadcast environment always affects the transmission quality in wireless sensor networks. In order to improve the SNR and communication rate, an opportunistic scheduling algorithm is adopted to schedule the sensor nodes which are in the good channel states. Multiple antennas are equipped at central node, the other nodes are equipped with single antenna to save energy and volume, which is a multiple input and single output multi-user system. The communication is divided into two stages: at first, the random unitary beamforming is generated by multi-antennas at the pilot stage;secondly, after receiving the pilot information, the sensor node determines whether to enter the communication state according to the preset threshold and then selects the corresponding random beam. The properly truncated threshold is given by Monte Carlo method through communication rate comparison under different situations. The results shows that the SNR and communication rate are both improved by the opportunistic scheduling.