Rapid Computation Algorithm for Radio Wave Propagation Characteristics on Airport Surface

This paper is concerned with an analysis of propagation characteristics on an airport surface by using the ray tracing method (RTM). The RTM is generally applied to an analysis of behaviors of electromagnetic waves in urban/suburban areas for such terrestrial broadcasting and cellular phone, and there were only few reports in a civil aviation research field. However, in aircraft surveillance systems in the airport, performance decrement arises due to the multipath interference. Therefore, it is important to investigate propagation characteristics in the airport. In this paper, we firstly propose an algorithm for rapid field computation based on the RTM. In the algorithm, we generate obstacles by triangular or rectangular faces, and we simplify the ray searching procedure by using the representative points of each obstacles´ face. That process enables us to compute electromagnetic fields as rapidly as possible. Next, we describe the computation method of electromagnetic field. Finally, we show ray distribution, delay profile and received powers as numerical examples. We discuss the computation time of the proposed method and the interferences of multipath which lead to the detection errors.