Broadband offset quad-ridged waveguide orthomode transducer

Villiers, Dirk I. L. de; Meyer, P.; Palmer, K.D.

doi:10.1049/el:20092887

Cited by 22 publications

(17 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Orthomode transducers (OMTs) are one of key components in both radio astronomy and telecommunication systems. Different OMT technologies were reported, such as the coupled waveguide, the planar, the finline, and the quardruple‐ridged waveguide (QRWG) OMTs. For radio astronomy applications, the OMTs with low cross‐polarization, low ohmic loss, and good impedance matching over a wide band are needed.…”

Section: Introductionmentioning

confidence: 99%

Compact wideband bowtie dipole orthomode transducer

Fan

Zhu

Yang

et al. 2019

Micro & Optical Tech Letters

View full text Add to dashboard Cite

A compact wideband orthomode transducer (OMT) with an octave bandwidth is proposed for a 0.56‐1.12 GHz receiver system in the five hundred meter aperture spherical radio telescope. The OMT operates in a cryostat at a temperature of 70 K and therefore it is critical to minimize its dimension while insuring good electrical properties. The complete OMT comprises 2 bowtie dipoles orthogonally arranged in a circular waveguide. Because of the innovative structure, competing modes, TM01 TE21, and TE01, have been effectively suppressed, and the bandwidth of the dominate mode TE11 has achieved to 2.08:1. The final optimized OMT has a length of 300 mm, shorter than a half of the popular quardruple‐ridged waveguide OMT. Measurements at room temperature agree well with simulation results, with a reflection coefficient below −10 dB for both polarizations and cross‐coupling levels of −30.5 dB over the whole required frequency range.

show abstract

Section: Introductionmentioning

confidence: 99%

Compact wideband bowtie dipole orthomode transducer

Fan

Zhu

Yang

et al. 2019

Micro & Optical Tech Letters

View full text Add to dashboard Cite

show abstract

“…Quadruple-ridge coaxial waveguide feed structures and OMTs have also been reported [15], [16]. Previously published quadruple-ridge OMTs [6], [17] and horn antennas [18], [19] based on a square waveguide geometry have ridges that are perpendicular to the opposing outer waveguide walls. The proposed OMT, shown in Fig.…”

Section: Introductionmentioning

confidence: 99%

Wideband Diagonal Quadruple-Ridge Orthomode Transducer for Circular Polarization Detection

Coutts

2011

IEEE Trans. Antennas Propagat.

View full text Add to dashboard Cite

A novel diagonal quadruple-ridge OMT with a compact geometry is proposed for detecting circularly polarized signals when used in conjunction with a 90 degree phase shifter. X-Band OMT prototypes, covering 8 GHz-12 GHz, have been fabricated and tested, and exceed specifications by a wide margin, with no evidence of trapped-mode resonances in the operating bandwidth. In addition to having good reflection and transmission performance, measured results show that the fabricated OMT performs well in separating orthogonal circularly polarized signal components. The OMT design is discussed in detail, focusing on impedance matching as well as the methods used to avoid in-band trapped-mode resonances. Since the OMT design focuses on performance, manufacturability and ease of tuning, the new design would be well suited to array applications. Furthermore, the new OMT design is amenable to multiple-pixel feeds as a result of its narrow geometry.

show abstract

“…By offsetting the pairs of orthogonal ridges in the direction of propagation, the OMT can be designed in such a way that the unwanted higher order even mode, causing the trapped mode resonance, is evanescent everywhere in the structure. This type of OMT is somewhat longer than the standard symmetric QRWG OMT, but it is very simple to design and construct and has similar performance [16]. The unwanted and desired modes will be described in detail in this paper, and a more detailed design procedure will be outlined than that presented in [16].…”

Section: Introductionmentioning

confidence: 99%

“…This type of OMT is somewhat longer than the standard symmetric QRWG OMT, but it is very simple to design and construct and has similar performance [16]. The unwanted and desired modes will be described in detail in this paper, and a more detailed design procedure will be outlined than that presented in [16]. A prototype OMT was designed and constructed to operate in the S-band between 2.4 and 4.0 GHz, and the simulated and measured results are presented.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Design of a wideband orthomode transducer

2009

View full text Add to dashboard Cite

The design of an offset ridge quad-ridged waveguide (QRWG) orthomode transducer (OMT) is presented. By offsetting one of the ridges in the direction of propagation, a much wider single mode operating bandwidth can be achieved than that achievable in a traditional symmetric QRWG OMT's. This wide single mode operating bandwidth ensures that no higher order modes are excited at the feeds of the OMT, which in turn eliminates unwanted resonances often observed in traditional QRWG OMT's. The performance of the OMT is similar to that of traditional types, with reflections below -20 dB and cross coupling below -40 dB across most of the desired 1.7:1 bandwidth.

show abstract

Broadband offset quad-ridged waveguide orthomode transducer

Cited by 22 publications

References 10 publications

Compact wideband bowtie dipole orthomode transducer

Compact wideband bowtie dipole orthomode transducer

Wideband Diagonal Quadruple-Ridge Orthomode Transducer for Circular Polarization Detection

Design of a wideband orthomode transducer

Contact Info

Product

Resources

About