基于马尔科夫链的60GHz点对点通信移动性优化

Improved 60 GHz peer to peer communications of mobile devices based on Markov chain

由于60 GHz通信在空气中可能会有高达20 dB的信号衰减,因此通信的范围和质量都可能受到影响.为此,IEEE802.11ad标准引入了能够定向增强信号和控制信号传播方向的波束成形技术来提高通信质量.然而,设备位置移动对波束成形的影响较大,它可能会导致通信质量下降甚至中断.为保证通信通畅,文中针对IEEE 802.11ad定义的点对点场景提出了波束成形优化算法.该算法基于马尔科夫链模型预测下一时刻设备的位置,并且提前调整相应的波束方向.该算法利用动态设备的相对位置和波束转动角度信息,代替了原波束成形方法中的波束扫描等过程.在仿真实验中,通过信息交互次数验证了该算法的有效性,提高了波束成形过程的效率,并且使该过程中的能量消耗降低了60%.

Since 60 GHz communications may have signal attenuation up to 20 dB,the working distance and qual-ity of the communications will be suffered .The beamforming technology has been introduced to improve the dis-tance and quality of the communications by making a beam propagate in a certain direction with increased signal strength .Meanwhile , the mobility of the device may also cause communication interruption according to the peer to peer communication according to the IEEE 802.11ad standard.In order to ensure the communication , we pro-pose an algorithm to improve the process of beamforming by predicting the next location of the mobile device based on Markov Chain .This algorithm provides both the location and beam rotation angle of the mobile device . Moreover , it takes the place of sector level sweep part of beamforming .Simulation shows the number of ex-changed messages between two devices has been decreased about 60% compared with the beamforming in the standard .