Study of a Fabry-Perot cavity in the microwave frequency range by the boundary element method

In order to describe very closely the operation of a quasi-optical multidiode oscillator using a Fabry-Perot cavity, each component must be modeled. The description of such a cavity by the boundary element method (BEM) is presented. The difficulties of adapting classical models to this practical case are discussed and justify the use of a more complete and flexible method such as the three-dimensional BEM. Two levels of approach are described. The first, which has been called zero order, is quite classical. The second is the second order approach. The evolution of the computed results as a function of the number and the distribution of the meshes is given. They are compared to analytical results and to measurements.>