A Parallel CE-LOD-FDTD Model for Instrument Landing System Signal Disturbance Analyzing

Abstract

Before a new airport runway is built, the electromagnetic compatibility of the instrument landing system (ILS) must be fully taken into consideration. The electromagnetic compatibility requirements for airports are becoming more and more complex, so rather than using traditional ray-tracing (RT) simulation models, a more accurate approach such as the finite-difference time domain (FDTD) is needed. The application of FDTD to ILS signal modeling suffers from an intensively high computation burden. The computation burden is owing to: 1) the FDTD has to loop a large number of time steps and 2) for every step, a huge number of cells has to be updated. This paper solves the above-mentioned issues by twofold. First, this model allows a large Courant–Friedrich–Levy number for the FDTD to reduce the total time step. This is achieved by combining the locally one-dimension (LOD) FDTD and the complex-envelope (CE) technique. The combination of CE, LOD, and FDTD (CE-LOD-FDTD) makes the model update with larger time step and retain the same level of accuracy. Second, we propose a set of novel GPU-based acceleration algorithms to update the field in parallel for reducing the computation time. By comparing the measurement results, it is shown that the FDTD model is more accurate than the traditional RT-based method. Our GPU-based CE-LOD-FDTD model is 22 times faster than the conventional parallel FDTD model in a multicore machine.