Efficient numerical–analytical tool for time domain obstacles detection

The aim of this work is to implement a mixed approach able to provide an efficient time domain solution of the electromagnetic (EM) coupling between an antenna and an obstacle distant few meters away. The idea is to divide the problem into a small number of less complex sub-problems exploiting the advantage of solving some of them by analytical models and the others by numerical codes. To this end, the electric field radiated by the antenna just close to the object has been sampled in time and spatial domains by means of a small number of plane waves; for each plane wave impinging on the object, the scattering problem has been solved by a commercial code; finally, the total echo has been obtained as analytical summation of all the scattering contributions at the antenna position. The resulting echo has been compared with that coming from a full-wave numerical solution, whereas the voltage signal received at the antenna port has been compared with that measured by experimental investigations. The positive results obtained demonstrate the possibility of using the tool to effectively study obstacle detection problems, for example as support to the design of an EM obstacles detector to improve visually impaired mobility