Design of X-band Moreno cross-guide coupler based on superformula curves

摘要

This article deals with the design of Moreno cross-guide couplers based on supershapesfor X-band applications. Crossed-waveguide couplers are mainly useddue to their compact structures. In these couplers, cross-aperture structuresare usually employed to offer flat coupling and high isolation. In the presentarticle, the possible shapes for apertures and metal inserts that can be derivedby the superfomula curves are explored and the effects of variations of superformulaparameters are investigated on the performance of Moreno coupler.Finally, the proposed Moreno coupler is validated through fabrication andmeasurement. The experimental validation shows an excellent agreement withthe simulated results. In the frequency range from 8 to 12.5 GHz, the measuredcoupling value changes from 18.8 to 20.8 dB and the directivity is better than38 dB and 29 dB from 8 to 11 GHz and 11 to 12.5 GHz, respectively. Theresults are valuable for the design and evaluation of broadband high directivewaveguide couplers.