Interference Path Loss Measurements of Beechcraft B300 Aircraft at 4 GHz Wireless Avionics Intra-Communication Band

Wireless Avionics Intra-Communication (WAIC) devices operate between 4,200 MHz and 4,400 MHz. This is the same frequency band as aircraft radio altimeters. In this paper, to investigate the coexistence conditions, the radio altimeter interference path loss (IPL) due to an assumed WAIC device is investigated. Firstly, an overview of the Beechcraft B300, a medium sized turboprop aircraft, is given. Then, the radio altimeter IPL measurement set-up is discussed. The measurement set-up and procedures are based on the RTCA DO-307A procedure. Finally, the IPL values are calculated using the measurement results. The minimum IPL value with the transmitting antenna inside of the cabin is 72.8 dB. This is not significantly small compared with that of the Airbus A321 (74.4 dB). In addition, the median IPL value with the transmitting antenna inside of the cabin is 90.9 dB.