Study of the invariants of the time-reversal operator for a dielectric cylinder using separate transmit and receive arrays: theory and experiments

In this paper, the DORT method applies to scattering analysis with arrays of transceivers. A large dielectric cylinder is observed by separate transmit and receive arrays with microwaves. First, the decomposition of the scattered field into normal modes and projected harmonics is used to determine the theoretical time-reversal invariants of the Time Reversal Operator. In a second part, we experimentally study the time reversal invariants for various dielectric cylinders. A good agreement is shown between theory and experimental results. The DORT method is finally used in an inverse problem to determine the different parameters of the cylinder, especially permittivity, diameter or location.