Design and test of a broadband rectangular waveguide TE ₁₀ –TE ₂₀ mode converter

Abstract

A broadband rectangular waveguide TE 10-TE 20 mode converter with high mode purity and conversion efficiency is designed, fabricated and measured in this Letter. Based on the broadband characteristic of ridged twist waveguide and its characteristic of polarisation direction torsion of electromagnetic wave, this mode converter achieves broadband and high-efficiency TE 10-TE 20 mode conversion. Simulation results reveal that the return loss of the proposed mode converter is >20 dB and insertion loss is <0.04 dB in whole Ka-band. Two prototype TE 20 mode converters were fabricated. Back-to-back millimeter-wave measurements by vector network analyser were performed to verify the design. The measured performances show return loss of the proposed mode converter is >20 dB and insertion loss is <0.1 dB in whole Ka-band, the corresponding mode conversion efficiency is >97.7%.

A compact rectangular waveguide TE10 to TE20 mode converter with coplanar and codirectional configuration

“…Table 1 provides comparisons with previous works. The converters in [3,4,6,9,11] don't possess coplanar and codirectional configuration. The converters in [5,8,12] suffer from difficult fabrication process because of bend waveguides or dielectric rods.…”

“…Thus, many kinds of mode converters are required to realize the excitation and extraction of higher order modes. Among these, rectangular TE 10 to TE 20 mode converter is basic and has been utilized as an intermediate employed in various applications, such as TE 01 and TE 21 launchers [1][2][3][4][5][6].…”

“…The existing TE 10 to TE 20 mode converters can in general be divided into the following types: (1) the "jog converter" composed of two oppositely oriented 45°bends, with a circular TE 01 -mode bend to realize mode coupling [1,7,8], (2) the right-angled H-plane converter composed of an overmoded waveguide and a standard one with one port short-circuited to realize mode excitation with lateral wall coupling [2,3,9,10], (3) the converter with input and output ports in different planes, utilizing a coupling aperture to realize mode conversion [4,11], (4) the converter utilizing power division and 180°phase difference between two paths by different path length or opposite transition structure [5,6], (5) the converter utilizing periodic dielectric rod arrays in a waveguide to realize unique dispersion property and mode conversion [12,13].…”

Design of a Slotted Waveguide Antenna Based on TE20 Mode in Ku-Band Suitable for Direct Metal Laser Sintering

“…To be able to work with TE20 mode propagation and to make measurements, a TE10 to TE20 mode converter needed to be developed. Waveguide mode converters have already been developed for many microwave applications [17,18]. The TE10 to TE20 mode converter in the present study was developed and designed based on the work reported in [19], considering the central frequency to be 15 GHz.…”