机载 PLC 信道传递函数建模与概率保证分析

Wiring can be made simpler and lighter by using power line communication (PLC) technology to replace some of the data cables used to connect avionics systems. According to airborne power line environment and avionics communication requirements, it is necessary to solve the problem of evaluating the real-time performance of PLC under the conditions of channel fading and interference. First of all, according to the wiring topology of the power lines in a certain aircraft, a modeling method of the PLC channel by transfer function is achieved in the form of a " bottom-up" construction with voltage ratio equations. Subsequently, the relationship between the transfer function, channel gain and instantaneous Shannon capacity is deduced. According to the effective capacity theory, by exploiting the relationship between the non-empty probability of the backlog queue and the quality of service (QoS) factor, It is possible to easily obtain the delay violation probability from the instantaneous Shannon capacity to evaluate the probabilistic guaranteeing of real-time performance. Simulation results verify the accuracy of our models and analysis to estimate the delay violation probabilities, and show the relationship between the delay limit and the violation probability under different channel transfer functions. They also demonstrate how the channel fading significantly affects the sustained real-time rate for airborne PLC systems under the probabilistic guaranteeing delay constraint.