Operating an In-Cabin Femto-Cellular System Within a Given LTE Cellular Network

An onboard mobile communication system can be operated when the height of an aircraft is above 3000 m and the maximum equivalent isotropic radiated power outside an aircraft is below -13 dBm for 200 kHz bandwidth in a 1800 MHz system based on the Electronic Communications Committee reports. However, in order to provide seamless connectivity for aircraft passengers, the onboard communication system should be in operation in every phase of the flight. Therefore, in this paper, the compatibility of an in-cabin long term evolution (LTE) 1800 MHz femto cellular system with the current terrestrial LTE 1800 systems are investigated when an aircraft is stationary on the ground. Edinburgh Airport in Scotland and the existing LTE cells that provide network coverage at the airport are modeled through a simulation platform. Three Airbus A321 aircraft are modeled, while stationary, in the parked position on the apron and an in-cabin LTE femto cellular system is deployed within each aircraft. Signal-to-noise-plus-interference ratio and power leakage from the in-cabin evolved NodeBs in the downlink direction are considered as performance metrics to investigate the coexistence of the terrestrial and in-cabin systems. The simulation results show that the in-cabin LTE 1800 MHz femto cellular system can be operated without causing any significant interference to the existing terrestrial LTE 1800 MHz system while the aircraft is parked on the apron. However, it may be advisable to only operate the system when the aircraft doors are closed, in order to mitigate any possible interference effect on the users who are boarding the aircraft through the passenger boarding bridge. According to the results shown for a linear apron concept, the legislation governing the onboard mobile communication systems should be revised, in order to pave the way to the goal of seamless mobile connectivity in the next generation of communication systems.