WiFi Directional Channel Modeling Research And Implementation

Radio channel modeling plays an important role in wireless communication technology evolution and the wireless communications industry chain, which provides the validation of new technologies and new propagation scenery as well as reduce the cost of measurement vendors. A radio channel simulating platform or channel emulator is often developed to reproduce the actual propagation fading under various propagations.The focus of radio channel modeling varies from time-frequency characteristics to the propagation characteristics of time domain, frequency domain and spacial domain. The research of multi-antenna systems shows:The statistical property of received signal in spatial domain affects the spacial correlation; Rich scattering environment of indoor propagation leads clustering phenomenon in both angle domain and delay domain. The delay of each multipath component of the intra-cluster shows exponential attenuation characteristic.IEEE 802.11n and IEEE 802.11 ac standard is commonly used in indoor wireless local area network, the related channel models based on Kronecker model,TGac and TGn,provide six typical scenarios and multi-cluster phenomena modeling in multi-antenna systems. The current radio channel emulator due to the limited hardware constraints, supports limited multipath number, while the multipath number in TGac channel model under 80MHz bandwidth exceeds the hardware ability. Our channel model has been redesigned to meet the hardware channel model proposed conditions without affecting system performance under the premise.Firstly the paper indicates the role of radio channel modeling and R&D in the field of radio channel emulator, and then describes the basics of wireless channel modeling, then there is an overview of the IEEE 802.11 standard TGn and TGac modeling.During the development of the radio channel emulator, due to the hardware limited conditions, the standard of TGac model is to be simplified, and we build a link level simulating platform to verify TGac simplified model by Bit Error Rate. The verification shows BER curves of simplified channel model fit the curves of the original channel model well.