Peer-to-peer VHF propagation path loss in the airport surface area

As recently noted, the wireless channel in the very high frequency (VHF) band has not been thoroughly quantitatively characterized for airport surface areas. For future services such as VHF Data Communications, channel characteristics are needed to enable system optimization. Given the narrow bandwidth of VHF communications (25 kHz), channel dispersion is not significant, but propagation path loss is vitally important. This paper serves as a companion paper to our prior work in the area of VHF propagation path loss modeling on the airport surface area (ASA). We made path loss measurements in the aeronautical VHF band at Clevel and Hopkins International Airport (CLE) in June 2011. The non-mobile transmitter used a continuous wave (sinusoidal) signal and a mobile receiver moved about the airport surface area in a prescribed path. Both transmitter and receiver were located in vans, enabling “peer-to-peer” propagation path loss estimation via basic link budget analysis. We obtained path loss data for both line-of-sight (LOS) and non-line-of-sight (NLOS) conditions, from which we derived the log-distance path loss models. The propagation path loss exponents were found to be approximately 4 for NLOS regions and 2.9 for LOS regions in Cleveland.