为了探索高频段室内无线体域网通信的可行性,对 11 GHz室内无线体域网的传播特性进行了测量与研究.基于大量的测量数据,给出了11 GHz频段室内无线体域网的路径损耗、阴影效应与均方根时延扩展的统计特性.针对体对体通信时人体相对角度变化的场景,提出了一种具有相对角度影响的路径损耗模型,该模型利用了与身体角度相关的路径损耗指数、浮动截距以及身体角度因子修正相对角度变化引入的路径损耗.为了验证模型的适用性,对比分析了在小型空教室和大型会议室两种不同场景下相对角度变化对信道传播特性的影响.研究结果表明:在收发端距离固定的情况下,路径损耗指数、浮动截距和由相对角度引起的路径损耗(Path Loss caused by Relative Angle,PLRA)均与相对角度具有三角函数关系;在收发端相对角度固定时,PLRA与收发端距离无关,仅与相对角度有关.上述研究结果可以为11 GHz频段在未来室内无线体域网的使用提供理论基础与实践依据.
Abstract
To explore the feasibility of high-frequency indoor wireless body area network(WBAN)communications,this paper delves into the propagation characteristics of indoor WBAN at 11GHz.Based on the extensive measured data,the statistical properties of path loss,shadowing effects,and root mean square delay spread are presented.Given a scenario where the relative angle changes in body-to-body communications,a path loss model with the impact of the relative angle is proposed.This model compensates the impact of the relative angle change on the path loss by using the path loss exponent,the floating intercept,and the body angle factor.To validate the applicability of the model,a comparative analysis is conducted in a small empty classroom and a big conference room.The results show that when the distance between the transmitter and the receiver is fixed,all of the path loss exponent,the floating intercept and the path loss caused by the relative angle have a trigonometric function relationship with the relative angle;when the relative angle between the transmitter and the receiver is fixed,the above three are not related to the distance between the transmitter and the receiver,but only to the relative angle.These results can provide a theoretical foundation and practical basis for future application of the 11GHz frequency band in indoor WBANs.
关键词
高频段/体域网/室内场景/路径损耗/均方根时延/相对角度
Key words
high frequency band/wireless body area network(WBAN)/interior scenario/path loss/root mean square time delay/relative angle