New Approach to Wave Oriented Radio Propagation Modeling Based on Extended FDTD Methods

Predicting the signal level and coverage area of radio frequency communication channels between base stations, vehicles and warfighters is a challenging problem. The channel may involve radio frequency interactions with hills, foliage, and buildings.The paths may involve long distances over hilly terrain or shorter distances involving interaction with urban building features. Some propagation paths may simultaneously involve hills, foliage, and urban areas. Existing methods for making physics-basedpredictions of radio propagation are limited to single classes of interactions, such as urban, terrain, or indoor. And even though physics-based, require approximations and assumptions that limit accuracy. In this effort it is proposed to extend theFinite Difference Time Domain (FDTD) method to allow full wave calculation of long distance radio propagation over irregular terrain. Remcom has already developed a commercial quality radio propagation prediction model based on high frequency ray methods.Future plans include extending the capabilities of this software to include more accurate propagation prediction over irregular terrain including area coverage, and to mixed paths. The proposed effort should result in the most accurate irregular-terrainpropagation model available. At present there is no commercial software network planning tool that will accurately predict radio propagation over irregular terrain, or over paths that simultaneously involve irregular terrain and urban features, or urbanfeatures and indoor locations, or any combination of these. The market for such a software product is large, including both commercial and DoD applications.