A new approach to analytical calculation of microstrip directional couplers with full structure symmetry
Keywords:directional coupler, microstrip directional coupler
A new approach to analytical calculation of directional couplers that have two symmetry planes, which is based on using input impedances of co-phase (symmetrical) and opposite-phase (asymmetrical) partial two-poles is suggested. Examples of using such approach for calculations of directional couplers on the basis of a coupled lines segment with three directivity types are discussed.
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