Analysis of Sub-Millimeter Wave Four-Port Quasi-Optical Circulator

In radar system, one of the most important devices is ferrite circulator. The circulator based on quasi-optical techniques at sub-millimeter wave frequencies own better performance than their waveguide equivalents This paper demonstrates state-of-the-art performance for four-port quasi-optical circulator with the Faraday rotation angle, the ellipticity and the insertion loss of the circulator when it operating at 500 GHz and 900 GHz, respectively. Following that some results of circulator when operating at those frequencies are given. An exact method based on matrix theory and Fourier-transformation techniques is employed in this paper to analyses QOFR.