Study and Characterization of TM sub ono Cylindrical Resonant Cavity Combiners
Abstract
In this investigation the TMono cylindrical resonant cavity combiner is studied and characterized with the objective of improving the understanding of the design parameters of this microwave circuit. The study portion of the investigation involves presenting the fundamental theory of the cylindrical resonant cavity and coaxial diode circuits which make up a cylindrical resonant cavity combiner, the general modelling of two-port resonant cavities, and the equivalent circuit impedance relations of the Kurokawa combiner model (2) which has been widely used by researchers in this area. The objective of using this model was to examine its applicability to higher-order TMono mode combiners. The characterization section includes the passive two-port measurement of impedance transmission coefficient on a TM020 test combiner under various circuit conditions. A correlation between the measured and calculated impedance at a single coaxial line is presented and the results demonstrate that the Kurokawa model generally replicates the measured response. However, it is shown that there exists a relationship between the coupling coefficient at the cavity/ coaxial line interface and the number of coaxial lines which must be included in the Kurokawa model. The results of the transmission measurements indicate that to achieve maximum combining efficiency, a high unloaded cavity Q must be maintained (i.e. through the use of small coaxial lines) and that the microwave absorber characteristic impedance must be minimized without causing instability in operation with IMPATT diodes.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 1981
- Accession Number
- ADA100491
Entities
People
- Donald L. Allen
Organizations
- Wright Laboratory