Design of 183GHz/325GHz dual-channel quasi-optical system

In this paper, the of design a183 GHz/325 GHz dual-channel quasi-optical system is presented. Given the input beam waist, one can design the reflectors in each channel and we can calculate the key parameters of output beam of each reflector by using the Gaussian beam theory. A three dimensional visual software SiMatrix based on diffracted Gaussian beam analysis method (DGBA) is used to simulate the dual-channel system to evaluate the RF performance of the system. The ideal far field can be calculated from the parameters of the output beam. A commercial simulation software GRASP (based on physical optics) is used as a third party tool to verify both the design and the accuracy of simulation result by SiMatrix. By comparing the far field simulated by SiMatrix and ideal far field with the prediction using GRASP, it is found that the design meets the requirement and that the simulation results from SiMatrix is in agreement with GRASP in the mainbeam of the farfield.