Research On Channel Model Of Millimeter Wave In Special Environment Of City Scene

The explosive growth of the mobile communication business has led to a boom in research on mobile communication technology of Fifth Generation(5G).The abundant spectrum resources contained in the above 24 GHz frequency band can effectively alleviate the current situation of spectrum resource strain,and the channel characteristic of this frequency band is one of the concerns of 5G technology.This paper studies the transmission characteristics of 28 GHz broadband signals in urban special environment.Main work contents include:(1)The channel characteristics of 28 GHz broadband signals in Urban Microcell(UMi)scenario.At present,most of the researches on high frequency wireless channel characteristics in the UMi scene only consider the simple street environment.Due to the complexity of environment in the actual UMi scenario,this paper selects the UMi scene with the existing street environment and open environment,and analyzes the small scale characteristics of the 28 GHz broadband signal in the special environment.In addition,according to the measured multipath angle data multi-path signal is divided in the two ends respectively.Through the comparison of the measurement results in the street environment and the open environment,it is found that the open environment is more obvious under the condition of NLOS.Under the condition of LOS,the multi-path effect is smaller.By analyzing the clustering results of multipath signals,we find that the results of clustering are carried out separately by using the angle of one end,and the actual angle power spectrum is more consistent.(2)The building loss characteristics of 28 GHz signals in Urban Microcell(UMa)scene.Firstly,based on the free space,the paper studied the relationship between the building loss and the elevation angle between the building block and measurement point in the case of the simple building block in UMa scene.It is found that the loss of buildings decreases with the decrease of elevation Angle.In addition,the paper measures the loss of buildings caused by several buildings in the area of high-rises and the distance between 250～500 m.The measured values of each shadow path are analyzed by combining the specific propagation environment.In this study,the variation of the additional loss of buildings at different distances was given,and the differences between the 30 m and 49 m height of the two base stations were shown.