A Statistical Spatio-Temporal Radio Channel Model for Large Indoor Environments at 60 and 70 GHz

Millimeter-wave radios operating at unlicensed 60 GHz and licensed 70 GHz bands are attractive solutions to realize short-range backhaul links for flexible wireless network deployment. We present a measurement-based spatio-temporal statistical channel model for short-range millimeter-wave links in large office rooms, shopping mall, and station scenarios. Channel sounding in these scenarios at 60 and 70 GHz revealed that spatio-temporal channel characteristics of the two frequencies are similar, making it possible to use an identical channel model framework to cover the radio frequencies and scenarios. The sounding also revealed dominance of a line-of-sight and specular propagation paths over diffuse scattering because of weak reverberation of propagating energy in the scenarios. The main difference between 60 and 70 GHz channels lies in power levels of the specular propagation paths and diffuse scattering which affect their visibility over the noise level in the measurements, and the speed of power decay as the propagation delay increases. Having defined the channel model framework, a set of model parameters has been derived for each scenario at the two radio frequencies. After specifying the implementation recipe of the proposed channel model, channel model outputs are compared with the measurements to show validity of the channel model framework and implementation. Validity was demonstrated through objective parameters, i. e., pathloss and root-mean-square delay spread, which were not used as defining parameters of the channel model.