A broadband 180° hybrid ring coupler using a microstrip-to-slotline inverter

13 Aug 2015

A new broadband 180° hybrid ring coupler with a Chebyshev return loss response, implemented in microstrip line, and a phase inverter using microstripto- slotline transitions, is presented. The transitions were constructed using via short circuits and optimized radial slot stubs. The manufactured prototype was found to operate over a 118% bandwidth in the frequency range 0.72-2.8 GHz.