Research On Beamforming Technology Based On IEEE 802.11ay Sensing

With the development of wireless communication technology,wireless devices such as smart phones are rapidly popularized,and spectral resources are becoming increasingly scarce.In order to solve this problem,Wi Fi standards such as IEEE 802.11ad/ay began to focus on the use of unlicensed,high-bandwidth,high-frequency millimeter wave(mm Wave)for communication.The mm Wave has some shortcomings such as large path loss and small coverage,and requires beamforming to generate high-gain directional narrow beams for communication.Besides,wireless sensing technology is becoming more and more mature.It can realize more new application services such as behavior recognition with wireless sensing technology.It will be a new trend of next generation wireless communication to introduce Wi Fi sensing into Wi Fi communication system.However,it has not yet supported Wi Fi sensing in the existing communication standards.In addition,Wi Fi sensing needs to receive the reflected waves from the target object for detection,which will take serious electromagnetic wave attenuation.Wi Fi sensing also needs to use beamforming technology to concentrate energy and directional beams to aim at the target object to achieve better Wi Fi sensing performance.It is visible that beamforming is very important both in mm Wave communication and Wi Fi sensing.Based on the IEEE 802.11 ay standard,this thesis focuses on the two aspects of Wi Fi communication and sensing joint beam training and sensingassisted communication beamforming.First of all,this thesis presents a Wi Fi sensing scenario,and proposes a Wi Fi communication and sensing joint beam training scheme based on IEEE 802.11 ay standard.This solution realizes the beam training of sensing and communication by adding a sensing beam training field to the original communication beam training frame in the A-BFT phase.It reuses the original communication frame,eliminating the need to allocate time slot resources for sensing beam training,and has better compatibility with the original old equipment.Then this thesis gives an analogy communication beam training method and staged sensing beam training,and combines the characteristics of sensing to propose an adaptive method of sensing beam training.The simulation results show that the latter is much lower than the former two sensing beam training costs.Then,this thesis discusses how to use sensing the STA location information service and communication beamforming obtained by sensing.Based on the STA location information obtained by the system through sensing,this thesis proposes a beam training scheme based on geometric models and KNN and the improved algorithms.It uses the sensing information to reduce the beam training range.The simulation results show that the above solution has a significant reduction in beam training overhead compared with the IEEE 802.11 ay traditional beam training scheme.Finally,this thesis uses the position information obtained by sensing to transform the beam tracking problem into the motion trajectory problem of the STA,and realizes the trajectory tracking of STA using the Kalman filter algorithm.The simulation results show that the position error of STA is reduced after the Kalman filter algorithm is used,and the beam tracking can be better realized.