Omnidirectional Small-Scale Fading Models in an Airport Environment at Millimeter-Wave Frequency Bands: 73 and 81 GHz

This paper presents omnidirectional small-scale fading measurements and analysis at millimeter-wave (mmWave) frequency bands −73 and 81 GHz −in an airport environment. More than 825 power delay profiles (PDPs) were measured at each mm Wave band in an outdoor airport and an indoor campus environment in Boise. These measurements yielded small-scale omnidirectional models and angular power profiles for both line-of-sight (LOS) and non-line-of-sight (NLOS) scenarios. Various angular combinations of PDPs were obtained by controlling the beam directions of the transmitter (TX) and receiver (RX) antennas using a gimbal. A linear track was employed at each receiver to move the antenna in half-wavelength increments. Measured data indicate that small-scale fading of received signal amplitudes follow both a Ricean and a log-normal distribution in the outdoor airport LOS and NLOS scenarios at 73 and 81 GHz bands. Results reveal that the cumulative distribution function curve is a Ricean distribution with K-factor ranging from 3 – 13 dB, and 21 – 27 dB and a log-normal distribution bounded by σ = 0.2 dB and σ = 0.35 dB for the LOS 81 GHz outdoor channel. Similar results can be seen at each band for the indoor campus environment. The indoor measurements show that the measured LOS curve is bounded by the Ricean distribution of K factor ranging from 8 to 13 dB, and log-normal distribution with σ = 0.2 to 0.25 dB, respectively in the indoor 73 GHz channel. The angular power profile results depict that main lobe power over all directions is higher at 81 GHz channel in comparison to the 73 GHz channel in both LOS and NLOS scenarios, as expected