Share Email Print
cover

Proceedings Paper

Dual-side backward coupler waveguide orthomode transducer for the 3 mm band
Author(s): Alessandro Navarrini; Renzo Nesti
Format Member Price Non-Member Price
PDF $14.40 $18.00
cover GOOD NEWS! Your organization subscribes to the SPIE Digital Library. You may be able to download this paper for free. Check Access

Paper Abstract

We describe the design, construction, and characterization results of a waveguide Orthomode Transducer (OMT) for the 3 mm band (84-116 GHz.) The OMT is based on a symmetric backward coupling structure and has a square waveguide input port (2.54 mm × 2.54 mm) and two single-mode waveguide outputs: a standard WR10 rectangular waveguide (2.54 mm × 1.27 mm,) and an oval waveguide with full-radius corners. The reverse coupling structure is located in the common square waveguide arm and splits one polarization signal in two opposite rectangular waveguide sidearms using broadband -3 dB E-plane branch-line hybrid couplers. The device was optimized using a commercial 3D electromagnetic simulator. The OMT consists of two mechanical blocks fabricated in split-block configuration using conventional CNC milling machine. From 84 to 116 GHz the measured input reflection coefficient was less than -17 dB, the isolation between the outputs was less than -50 dB, the cross polarization was less than -30 dB, and the transmission was larger than -0.35 dB at room temperature for both polarization channels. The device is suitable for scaling to higher frequency.

Paper Details

Date Published: 21 July 2008
PDF: 12 pages
Proc. SPIE 7020, Millimeter and Submillimeter Detectors and Instrumentation for Astronomy IV, 70202M (21 July 2008); doi: 10.1117/12.791198
Show Author Affiliations
Alessandro Navarrini, INAF, Cagliari Astronomy Observatory (Italy)
Renzo Nesti, INAF, Arcetri Astrophysical Observatory (Italy)


Published in SPIE Proceedings Vol. 7020:
Millimeter and Submillimeter Detectors and Instrumentation for Astronomy IV
William D. Duncan; Wayne S. Holland; Stafford Withington; Jonas Zmuidzinas, Editor(s)

© SPIE. Terms of Use
Back to Top