Lumped Element Model of a Transdirectional Coupled Line Coupler

Transdirectional coupled line couplers have gained a lot of attention due to their isolation between the input and output ports as compared with other traditional directional couplers. A novel fully lumped element model for the transdirectional coupler with generic equations for a given coupling coefficient is presented. Capacitors are used to represent the coupling mechanism between the two coupled lines. A lumped element transdirectional coupler design with 3 dB coupling will be presented and results given.