Full-wave analysis of a new microstrip-to-waveguide interconnect configuration

This paper presents a new interconnect configuration between microstripline and rectangular waveguide that yields a transition from one microstripline port to two waveguide ports. Most current transitions employ only one wave guide port. Electromagnetic coupling takes place through a slot in the narr ow wall of the rectangular waveguide that coincides with a slot in the grou nd plane of the dielectric slab. Introduction of an E-plane waveguide fin y ields additional control over the insertion loss level. The numerical metho d employed in the analysis, which makes use of Green's function expressions in a moment-method solution, is also described and numerical details are p resented. Measured results verify the accuracy of the numerical model and i llustrate that it is possible to obtain insertion loss levels of 0.25 dB wi th this configuration. Design data and a sensitivity analysis presented her e further characterize the interconnect.