Helical coupler from rectangular-to-circular waveguide.
Abstract
The very-large-array (VLA) radio telescope utilizes a low-loss TE-01 circular waveguide transmission system. During the design of this system a coupler was developed which couples directly from a standard millimeter rectangular waveguide to the TE-01 mode in highly overmoded circular waveguide. In contrast to previous couplers which used periodically spaced groups of coupling holes, this design wraps the rectangular waveguide in a helix around the circular waveguide to give a continuous array of coupling apertures for maximum coupling and a compact mechanical configuration. In particular, couplers have been designed and fabricated which couple from WR-28 (26.5-40 GHz) and WR-22 (33-50 GHz) rectangular waveguides to the TE-01 mode in 20- and 60-mm-diam circular waveguide.
- Publication:
-
IEEE Transactions on Microwave Theory Techniques
- Pub Date:
- November 1976
- DOI:
- 10.1109/TMTT.1976.1128972
- Bibcode:
- 1976ITMTT..24..847P
- Keywords:
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- Antenna Couplers;
- Helical Antennas;
- Radio Telescopes;
- Rectangular Waveguides;
- Transmission Efficiency;
- Waveguides;
- Antenna Arrays;
- Antenna Design;
- Cross Sections;
- Directional Antennas;
- Microwave Coupling;
- Propagation Modes;
- Very Large Array (Vla);
- Electronics and Electrical Engineering