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- Rahiminejad, Sofia, 1987, et al.
(författare)
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AMC pin waveguide flange for screw redundant millimeter and submillimeter measurements
- 2016
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Ingår i: 87th ARFTG Microwave Measurement Conference: Measurements for Emerging Communications Technologies, ARFTG 2016. - 9781509013081 ; , s. 7501946-
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Konferensbidrag (refereegranskat)abstract
- Measurements with waveguide flanges at frequencies above 100GHz have a considerable issue with leakage due to problems with achieving good electrical contact between the opposite flanges. The higher the frequency, the higher is the requirement for full contact. However, by using an artificial magnetic conducting (AMC) flange on one side of the interface, full electric contact is not needed between the two joining flanges. The AMC is realized as a pin-surface, and the leakage is stopped by a parallel-plate stopband like in gap waveguides. This paper describes how these AMC pin waveguide flanges can be used for screw redundant measurements.
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| 2. |
- Rahiminejad, Sofia, 1987, et al.
(författare)
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Design of micromachined ridge gap waveguides for millimeter-wave applications
- 2011
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Ingår i: Procedia Eng.. - : Elsevier BV. ; 25, s. 519-522
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Konferensbidrag (refereegranskat)abstract
- The ridge gap waveguide is a new transmission line for millimeter-wave applications. Traditionally, rectangular waveguides are used for those applications due to their low loss. However their fabrication requires precision machining, very good electrical contact and alignment between two joining mechanical parts. Ridge gap waveguides can obtain similar performance without requiring conductive sidewalls and this provides more freedom during the fabrication and assembly process as the structure is no longer sensitive to small gaps between the side walls and the upper lid. The ridge gap waveguide has already been validated for 10-20 GHz using conventional fabrication methods. The ridge gap waveguide prototypes presented in this paper are designed to work in the frequency region between 210 and 340 GHz, and fabricated using MEMS technology. MEMS technology provides fabrication precision of the structures and thus opens the path for high-frequency components.
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| 3. |
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| 4. |
- Rahiminejad, Sofia, 1987, et al.
(författare)
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Micromachined Ridge Gap Waveguide and Resonator for Millimeter-Wave Applications
- 2012
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Ingår i: Sensors and Actuators, A: Physical. - : Elsevier BV. - 0924-4247 .- 1873-3069. ; 186, s. 264-269
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Tidskriftsartikel (refereegranskat)abstract
- The ridge gap waveguide is a fundamentally new high-frequency waveguide. It does not need any electrical contact between the split blocks which gives it an advantage compared to the rectangular waveguide which is the standard today. These waveguides are conventionally fabricated by milling, although above 100 GHz milling is not adequate anymore. MEMS technology on the other hand, can offer high-precision fabrication and thus opens the path for new types of high-frequency components. In this paper both a ridge gap waveguide and a ridge gap resonator have been fabricated for the frequencies 220–325 GHz using MEMS technology. Support packages have been designed to enable device measurements. Simulations show that the reflection coefficient for the ridge gap waveguide is below −15 dB between 240 and 340 GHz. Two resonance peaks were measured at the frequencies 234 GHz and 284 GHz for the ridge gap resonator with unloaded Q-values of 336 and 527 respectively. Both the waveguide and resonator have the potential to obtain similar performances as the rectangular waveguide without strict requirement on electrical contact, allowing simplified fabrication and assembly technique.
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| 5. |
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| 6. |
- Rahiminejad, Sofia, 1987, et al.
(författare)
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Polymer Gap Adapter for Contactless, Robust, and Fast Measurements at 220-325 GHz
- 2016
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Ingår i: Journal of Microelectromechanical Systems. - : Institute of Electrical and Electronics Engineers (IEEE). - 1057-7157 .- 1941-0158. ; 25:1, s. 160-169
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Tidskriftsartikel (refereegranskat)abstract
- Radiation leakages are a considerable problem when measuring waveguide structures at high frequencies. In order to maintain good electrical contact, flanges need to be tightly and evenly screwed to the device under test. This can be a time-consuming operation, especially with repeated measurements. We present a metamaterial-based adapter, which prohibits leakage even in the presence of gaps at the interconnects. This so-called gap adapter has been fabricated from a metallized polymer (SU8). The reflection coefficient is below -20 dB throughout the band for a 50-mu m gap on both sides of the gap adapter. In comparison, a conventional waveguide with a 50-mu m gap on both sides has a reflection coefficient of -10 dB. The gap adapter can be used to perform fast measurements, since the normal flange screws are redundant. We compare the SU8 gap adapter with a Si version and to a smooth metal waveguide reference disc. The SU8 gap adapter performed better than the Si version and much better than the waveguide disc in all test cases. SU8 gap adapters were used to measure on a waveguide component. The SU8 gap adapters with 50-mu m gaps performed comparable with the waveguide component with the flange screws carefully tightened. The polymer also makes the gap adapter mechanically robust and easy to mass fabricate. [2015-0113]
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