A directivity enhancement technique of shunt-inductive loading is demonstrated for asymmetric coupled line backward-wave directional couplers. Through rigorous normal-mode analysis, the exact condition for isolation zero is derived. Experimental results for a 5dB coupler at 0.9GHz show as much as 33dB improvements in the directivity over its conventional counterpart.
All Science Journal Classification (ASJC) codes
- Electrical and Electronic Engineering