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Advanced designs for non-imaging submillimeter-wave Winston cone concentrators



Andrew O. Nelson, Erich N. Grossman


We describe the design and simulation of several non-imaging concentrators designed to couple submillimeter wavelength radiation from free space into highly overmoded, rectangular, WR-10 waveguide. Previous designs are altered to improve the uniformity of efficiency rather than the efficiency itself. The concentrators are intended for use as adapters between instruments using overmoded WR-10 waveguide as input or output and sources propagating through free space. Previous simulation and measurement have shown that the angular response is primarily determined by the Winston cone and is well predicted by geometric optics theory while the efficiencies are primarily determined by the transition section. Additionally, previous work has shown insensitivity to polarization, orientation and beam size. Several separate concentrator designs are studied, all of which use a Winston cone (also known as a compound parabolic concentrator) with an input diameter ranging from 4 mm to 16 mm, and "throat" diameters of less than 0.5 mm to 4 mm as the initial interface. The use of various length adiabatic circular-to-rectangular transition sections is investigated, along with the effect of an additional, 25 mm waveguide section designed to model the internal waveguide of the power meter. Adapters without a transition section and a rectangular Winston cone throat aperture and double cone configurations are also studied. Adapters are analyzed in simulation for consistent efficiency across the opening aperture.
Proceedings of SPIE


compound parabolic concentrator (CPC), concentrator, overmoded waveguide, power meter, submillimeter-wave, terahertz (THz), Winston cone, PM4, Thomas Keating power meter, metrology


Nelson, A. and Grossman, E. (2014), Advanced designs for non-imaging submillimeter-wave Winston cone concentrators, Proceedings of SPIE, [online], (Accessed April 12, 2024)
Created May 21, 2014, Updated November 10, 2018