悬挂式单轨交通智能巡检车车地无线通信方案研究

由于悬挂式单轨结构特殊,对轨道梁健康状态的巡检需借助于智能巡检车,因此智能巡检车的运行状态和巡检数据的可靠、实时、稳定回传是实际工程实施中面临的难题.通过采用边缘计算和数据压缩技术降低数据传输带宽,对比自建、租用和共享3种车地无线通信方案,提出结合LTE-M和WLAN的车地无线通信方案.即在非运营时段,利用正线上的LT...     

Improvements on Analytical Models for IEEE 802.11e EDCF Differential Services

Zhu introduced typical analytical models to simulate the 802. 11e EDCF channel access protocol. But our analysis indicates that there are some inaccurate derivations in his presentation. This paper intends to improve analytical model with some corrections. Furthermore, for the probability of the channel being busy pb in Zhu＇s model, different points and analysis method are proposed. When the network is under saturation condition, the new results about the probabilities of collision and channel busy, transmission probabilities, successful transmission probabilities, throughput and MAC layer latency are presented.