Comparison of the millimeter wave path loss estimation model with outages

The millimeter wave is in an extremely high frequency band whose frequency and wavelength ranges are 30–300 GHz and 10–1 mm, respectively. Owing to the large distance loss and weak diffraction, a channel in the millimeter wave band experiences a propagation loss that is much worse than that of a low frequency band. When the path loss in the millimeter wave band is measured, it is observed that the data is confined within a certain range owing to limitations. If the original least square is applied to the measurement data without considering the limitations of certain values, the path loss exponent can be underestimated. Therefore, both censoring and truncation environments should be taken into account in the regression model. In this paper, the performance of the Tobit maximum likelihood estimation, Heckman two-stage model and truncation regression model are compared with the ray-tracing simulation.