Analysis and optimization of a Ka-band directional coupler

An analysis and optimization procedure is described for the design of branch-waveguide directional coupler which gives results showing a significant improvement over previous researchers' theory. A Ka-band 10dB directional Coupler is designed based on theories synthesized by former researchers; however, it is impossible to utilize the certificated models directly, because some of them can not be realized by present fabrication technology. Simulations and optimizations were carried out, and finally a model satisfied our needs is obtained. Measurement results show its good performance over the frequency band of 24GHz to 34GHz.