Characterization Techniques of Millimeter-Wave Orthomode Transducers (OMTs)
We report on advanced techniques for the accurate characterization of millimeter-wave Orthomode Transducers (OMTs) enabling the derivation of the fundamental parameters of such devices, i.e., the insertion loss, the return loss, the cross-polarization, and the isolation. These techniques include sta...
| Main Authors: | , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2021-07-01
|
| Series: | Electronics |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2079-9292/10/15/1844 |
| _version_ | 1797525685341782016 |
|---|---|
| author | Alessandro Navarrini Renzo Nesti |
| author_facet | Alessandro Navarrini Renzo Nesti |
| author_sort | Alessandro Navarrini |
| collection | DOAJ |
| description | We report on advanced techniques for the accurate characterization of millimeter-wave Orthomode Transducers (OMTs) enabling the derivation of the fundamental parameters of such devices, i.e., the insertion loss, the return loss, the cross-polarization, and the isolation. These techniques include standard frequency-domain and time-domain VNA (Vector Network Analyzer) measurement methods, which can be applied to remove the effects of the waveguide transitions necessary to access the OMT ports and excite the desired modes. After reviewing the definition of the OMT parameters, we discuss the test equipment, the VNA calibration procedures as well as the VNA time-domain time-gating method for application in OMT characterization. We present simplified equations that relate the calibrated VNA measured quantities with the OMT S-parameters, illustrate various characterization methods, and examine various OMT experimental test setups. The advantages and disadvantages of each of the OMT characterization procedures are presented and compared among them. We provide a list of waveguide components required in the OMT test setups (adapters, loads, quarter-wave and longer waveguide sections, feed-horn, etc.), discuss the error terms introduced by such components and examine their impact on the measured values. Furthermore, we identify strategies to mitigate or remove the effects of the measured errors, to derive the desired OMT parameters. Different OMT configurations, with a distinct orientation of the waveguide input and outputs, are discussed. Although the presented techniques refer to the characterization of a specific configuration of a W-band OMT, the described methods can be applied to other OMT configurations and frequency ranges (from microwave to THz frequencies), therefore having a general validity. |
| first_indexed | 2024-03-10T09:17:25Z |
| format | Article |
| id | doaj.art-f31b2f3caeb1481bbec40051da6fba21 |
| institution | Directory Open Access Journal |
| issn | 2079-9292 |
| language | English |
| last_indexed | 2024-03-10T09:17:25Z |
| publishDate | 2021-07-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Electronics |
| spelling | doaj.art-f31b2f3caeb1481bbec40051da6fba212023-11-22T05:31:47ZengMDPI AGElectronics2079-92922021-07-011015184410.3390/electronics10151844Characterization Techniques of Millimeter-Wave Orthomode Transducers (OMTs)Alessandro Navarrini0Renzo Nesti1INAF (National Institute for Astrophysics), Astronomical Observatory of Cagliari, 09047 Selargius, ItalyINAF (National Institute for Astrophysics), Astrophysical Observatory of Arcetri, 50125 Firenze, ItalyWe report on advanced techniques for the accurate characterization of millimeter-wave Orthomode Transducers (OMTs) enabling the derivation of the fundamental parameters of such devices, i.e., the insertion loss, the return loss, the cross-polarization, and the isolation. These techniques include standard frequency-domain and time-domain VNA (Vector Network Analyzer) measurement methods, which can be applied to remove the effects of the waveguide transitions necessary to access the OMT ports and excite the desired modes. After reviewing the definition of the OMT parameters, we discuss the test equipment, the VNA calibration procedures as well as the VNA time-domain time-gating method for application in OMT characterization. We present simplified equations that relate the calibrated VNA measured quantities with the OMT S-parameters, illustrate various characterization methods, and examine various OMT experimental test setups. The advantages and disadvantages of each of the OMT characterization procedures are presented and compared among them. We provide a list of waveguide components required in the OMT test setups (adapters, loads, quarter-wave and longer waveguide sections, feed-horn, etc.), discuss the error terms introduced by such components and examine their impact on the measured values. Furthermore, we identify strategies to mitigate or remove the effects of the measured errors, to derive the desired OMT parameters. Different OMT configurations, with a distinct orientation of the waveguide input and outputs, are discussed. Although the presented techniques refer to the characterization of a specific configuration of a W-band OMT, the described methods can be applied to other OMT configurations and frequency ranges (from microwave to THz frequencies), therefore having a general validity.https://www.mdpi.com/2079-9292/10/15/1844orthomode transducervector network analyzers-parameterscharacterization techniquestime domainfrequency domain |
| spellingShingle | Alessandro Navarrini Renzo Nesti Characterization Techniques of Millimeter-Wave Orthomode Transducers (OMTs) Electronics orthomode transducer vector network analyzer s-parameters characterization techniques time domain frequency domain |
| title | Characterization Techniques of Millimeter-Wave Orthomode Transducers (OMTs) |
| title_full | Characterization Techniques of Millimeter-Wave Orthomode Transducers (OMTs) |
| title_fullStr | Characterization Techniques of Millimeter-Wave Orthomode Transducers (OMTs) |
| title_full_unstemmed | Characterization Techniques of Millimeter-Wave Orthomode Transducers (OMTs) |
| title_short | Characterization Techniques of Millimeter-Wave Orthomode Transducers (OMTs) |
| title_sort | characterization techniques of millimeter wave orthomode transducers omts |
| topic | orthomode transducer vector network analyzer s-parameters characterization techniques time domain frequency domain |
| url | https://www.mdpi.com/2079-9292/10/15/1844 |
| work_keys_str_mv | AT alessandronavarrini characterizationtechniquesofmillimeterwaveorthomodetransducersomts AT renzonesti characterizationtechniquesofmillimeterwaveorthomodetransducersomts |