Analysis and design of W-band branch-guide coupler

In this paper, a method of analysis and design of branch waveguide coupler is discussed for power allocation, compound and monitoring. This method called even-odd mode which gives any coupling ratio and any number of branch-guide with perfectly match, high isolation and low insertion loss. The expression is deduced in the paper and according to the method, an 8dB coupler in W band is easily designed with perfect simulation, while the measuring results is a bit off the simulation for some reasons. This kind of method is effective for designing the branch waveguide coupler.