PROJECT TITLE :

Modified coupled line trans-directional coupler with arbitrary power divisions and its application to a 180° hybrid

ABSTRACT:

A modified trans-directional (TRD) coupler for designing compact coupled line a hundred and eighty° hybrid with non-interspersed input/output ports is proposed. The modified TRD coupler which is composed of a coupled line and three different shunt capacitors features the characteristic of arbitrary power division and dc blocking. Style equations for the changed TRD coupler are derived using the ABCD matrix. Based on the modified TRD coupler and combined with the coupled line contra-directional (CTD) coupler, a novel coupled line a hundred and eighty° hybrid is made. It inherits the characteristics of the changed TRD coupler together with arbitrary power division and dc blocking. Moreover, the input and output ports of the 180° hybrid are non-interspersed. Within the topology of the proposed 180° hybrid, no bond wires, via holes or multilayer structures are required. The configuration of the one hundred eighty° hybrid is analysed and the design equations are derived. Using the design equations, the coupling coefficients of the CTD and therefore the modified TRD coupler will be flexibly chosen in line with different fabrication conditions. As an example to validate the feature of the proposed one hundred eighty° hybrids, 2 prototypes with 3 and half dozen dB coupling coefficients are devised. The measured results are in smart agreement with the simulated ones.