Design study of a fundamental mode input coupler for a 372-GHz gyro-TWA I : rectangular-to-circular coupling methods

Garner, Jason R. and Zhang, Liang and Donaldson, Craig R. and Cross, Adrian W. and He, Wenlong (2016) Design study of a fundamental mode input coupler for a 372-GHz gyro-TWA I : rectangular-to-circular coupling methods. IEEE Transactions on Electron Devices, 63 (1). pp. 497-503. ISSN 0018-9383 (https://doi.org/10.1109/TED.2015.2501028)

[thumbnail of Garner-etal-IEEE-TED-2015-Design-study-of-a-fundamental-mode-input-coupler-for-a]
Preview
Text. Filename: Garner_etal_IEEE_TED_2015_Design_study_of_a_fundamental_mode_input_coupler_for_a.pdf
Accepted Author Manuscript

Download (3MB)| Preview

Abstract

The design of two fundamental mode rectangular-to-circular waveguide input couplers for a low-terahertz gyrotron-traveling wave amplifier (gyro-TWA) is presented. A T-junction input coupler with a Bragg reflector and a multiple-hole directional coupler were optimized for operation between 360 and 384 GHz, the proposed gyro-TWA bandwidth. The T-junction coupler and the multiple-hole coupler achieved the respective bandwidths of 10% and 35%. The benefits and potential limitations of the low-terahertz wave coupler topologies are discussed alongside the challenging manufacturing methods of the submillimeter-wave components.