Performance Trade-Offs of an Optical Wireless Communication Network Deployed in an Aircraft Cockpit

In this article, we explore the performance of optical wireless technology for ensuring audio communications inside an aircraft cockpit. One advantage is that, unlike radio frequencies, opaque objects block optical signals and, therefore, signals cannot pass through walls. This can reduce security risks against eavesdropping and hacking of the physical layer, which is one of the main concerns in the aviation environment. However, optical wireless technology faces some issues, including range limitation and sensitivity to blockages. To study the achievable performances, we propose a modeling of the channels for the uplink and the downlink between the headsets of the four pilots of an Airbus A350 and the access point at the cockpit ceiling. A ray-tracing approach associated with a Monte-Carlo method takes into account the 3D geometric model of the cockpit, the presence of the pilots and their movements. We show that using spatial diversity for headset transceivers can improve performance. Using IEEE 802.11 medium access control mechanism to ensure multi-user communication, the approach highlights the trade-offs between power and delay for a successful communication, linked to the maximum achievable data rate for a given performance level.