Performance of Avionics systems is dictated by the timely availability and usage of critical health parameters. Various sensors are extensively used to acquire and communicate the desired parameters. In today's scenario, sensors are hardwired. The number of sensors is growing due to automation which increases the accuracy of intended Aircraft functions. Sensors are distributed all over the Aircraft and they are connected through wired network for signal processing and communication. LRUs (Line Replaceable Unit) which are integrating various sensors also use a wired approach for communication.
The use of a wired network approach poses challenges in terms of cable routing, stray capacitances, noise, mechanical structure and added weight to the structure. The weight of cables contributes significantly to the overall weight of the aircraft. As the weight of Aircraft increases, the required fuel quantity also increases. The Key driver for Airline operational cost is fuel. Fuel quantity is a direct function of weight.
Use of wireless sensors in aircraft brings in tremendous advantages in terms of design optimization, flexibility in sensor configuration and weight optimization. Even though the avionics industry is trying to adopt wireless sensors, there are some points of concern in deploying wireless sensors and networks across the aircraft.
This paper describes the comparative performance of wired and wireless sensors, type of wireless sensors & interfaces, frequency performance, protocols, network topologies and qualification standards. This paper also discusses the constraints and challenges in deploying wireless sensor network across the aircraft.