A Study Of Millimeter Wave Channel Modeling Indoor Environments Based On Ray Tracing Method

With the increasing use of wireless devices and developments of mobile communications,frequency resource shortage has become a challenging problem.One possible solution is to move frequency up into millimeter wave(mmWave)bands,which can offer wider bandwidth than lower frequency bands to achieve higher data rates.These features make mm Wave communication a key technology for 5G wireless communications to realize high data rate short-range communications.Before designing and implementing the mm Wave communication systems,it is of vital importance to study the mm Wave channel characteristics through channel modeling and measurement.Based on geometrical optic(GO)and uniform theory of diffraction(UTD),ray tracing method uses computer simulation to approximate the radio wave propagation,provides an accurate and efficient method to modeling the wireless channel.The thesis overviewed the research background about the next generation communication system at home and aboard,illustrated the principles of ray tracing algorithm,introduced its application in channel modeling and conducted ray tracing based 60 GHz indoor channel model.When modeling the 5G mm Wave channel,channel characteristics including the azimuth and elevation angle in angular domain,high resolution delay domain properties,and small-scale fading properties should take into consideration.This paper investigated the 60 GHz indoor channel by means of ray tracing algorithm,given intuitive and reliable analysis about the multipath components and channel characteristics in delay and angular domain,and conducted a deterministic channel model.The main contributions of this paper are illustrated as follows:Firstly,a lab office was chosen as a typical implementation scenario of mm Wave communication,the size and structure of buildings and objects in this scenario was measured precisely.The 3D environment model was sketched up in equal proportion with the real room to sustain the following propagation simulation.Secondly,conducted the ray tracing based simulation,compared the simulation results with space-alternating generalized expectation-maximization(SAGE)estimation results from channel measurement.The validity of ray tracing model was certificated by the good agreement of power delay profile and power angular profile between simulation results,measurement results and estimation results.Thirdly,compared the calculation complexity of ray tracing algorithm under this scenario to determine the reasonable calculation accuracy for conducting multi position simulation,and analyzed the statistical properties of delay spread and angular spread of 60 GHz indoor channel.Finally,clustered the.multipath components by K-means algorithm,adopted the angular cluster extended Saleh-Valenzuela(S-V)model to setup a deterministic channel model and analyzed the channel characteristics.