Low Loss Lumped Element Isolator Using Gyrator Circuit With Two Asymmetrical Electrodes

The equations of the insertion loss and the isolation bandwidth of low loss two-port isolator were derived from equivalent circuit using perturbation theory. The equations show that the insertion loss gets lower in proportion to the ratio of inductors of two electrodes, while the isolation bandwidth gets narrower nearly in the proportion to the ratio. A 3.2 times 2.5 times 1.4mm³ cellular phone isolator which volume was 44% of the conventional products was realized using two electrodes of asymmetrical structure that inductance of one was much larger than that of the another