A COMPUTATIONALLY EFFICIENT APPROACH TO MICROWAVE CIRCUIT MODELING OFCOMPLEX HIGH-TEMPERATURE SUPERCONDUCTOR CIRCUITS

A computationally efficient approach to modeling complex high temperat ure superconductor (HTS) microwave circuits is described which combine s two-dimensional electromagnetic solutions of microwave transmission lines, incorporating a phenomenological description of HTS behavior, w ith conventional commercially available microwave-circuit computer-aid ed-design software. Internal inductance effects are known to have a su bstantial impact on the design and implementation of narrowband HTS ci rcuits. Phase velocities and characteristic impedances can be well mod eled using a phenomenological description of HTS superconductivity alo ng with a generalized approximate boundary condition and a two dimensi onal electromagnetic solution to the waveguiding structure. Resultant parameterized design equations can then be incorporated into standard commercially available microwave-circuit computer-aided-design softwar e. The test case examined in detail was the superconducting channelize d receiver delivered by the Naval Research Laboratory to Phase II of t he High Temperature Superconducting Space Experiment. Excellent agreem ent was obtained between measurements made on the demultiplexer and th is HTS microwave circuit modeling approach.