A Broadband Ka-Band Waveguide Magic-T With Compact Inner Ridge Matching

In this letter, a broadband waveguide magic-T with compact size is presented. A grounded suspended stripline has been used to obtain broadband isolation characteristics and increase power capacity. The inner ridge-matching structure is used to achieve broadband matching. The method and design process of the demonstrated magic-T are described in detail. The measured 15-dB bandwidth is about 30.3%, almost for waveguide BJ-320 waveguide operating bandwidth. The measured isolation between sum and deference ports is above 37.5 dB; 20-dB measured isolation is achieved between collinear ports. The measured and simulated results are in good agreement. It has advantages in high-power applications.