Circular waveguide-to-microstrip transitions

A new circular waveguide-to-microstrip transition consisting of a microstrip probe inserted in a circular waveguide has been developed. Experimental results show that the transition has an insertion loss of less than 0.05 dB, and a return loss greater than 20 dB in the frequency range 8.72 – 10.66 GHz. This design can easily be scaled to other frequencies.