3 × 2 channel waveguide gyroscope couplers: Theory

Gyroscope couplers with three input ports and two output ports which can be implemented in a planar geometry are studied theoretically. Using a local normal mode description in the approximation of coupled mode theory, analytic output power expressions are obtained for the 3 × 2 branching waveguide coupler and the 3 × 2 directional waveguide coupler. When optimized, these devices behave identically to each other and to the three-dimensional 3 × 3 coupler [1] from which they are derived.