| 1. |
- Alfonso Alos, Esperanza, 1979, et al.
(författare)
-
Gap waveguide components for millimeter-wave systems. Couplers, filters, antennas, MMIC packaging
- 2012
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Ingår i: IEEE Antennas and Propagation Society, AP-S International Symposium (Digest). - 1522-3965. - 9784885522703 ; , s. 243-246
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Konferensbidrag (refereegranskat)abstract
- Design of passive components (couplers, filters and antennas) and MMIC packaging validation intended for RF front ends for microwave links at 38 GHz using gap waveguide technology have been shown. The use of this technology allows all-in-one integration of receiver, transmitter, and diplexer including the antenna into one mechanical unit. These initial designs and studies have been made at the microwave band for validation and measurement purposes, and for comparison with existing technology. They represent the first step towards the application of gap waveguides to millimeter-wave systems, where gap waveguides could have a large potential.
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| 2. |
- Algaba Brazalez, Astrid, 1983, et al.
(författare)
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Evaluation of losses of the ridge gap waveguide at 100 GHz
- 2013
-
Ingår i: IEEE Antennas and Propagation Society, AP-S International Symposium (Digest). - 1522-3965. - 9781467353175 ; , s. 1456-1457
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Konferensbidrag (refereegranskat)abstract
- An evaluation of losses of the Ridge Gap Waveguide (r-GAP) at 100 GHz has been developed in terms of Quality Factor. For this aim, an r-GAP resonator has been designed, simulated and measured. The feeding to the circuit is provided via a transition from Micostrip-to-Ridge Gap Waveguide based in electromagnetic coupling in order to ensure compatibility with the available probe stations.
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| 3. |
- Algaba Brazalez, Astrid, 1983, et al.
(författare)
-
Improving microstrip filters with gap waveguide packaging
- 2011
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Ingår i: Proceedings of the 5th European Conference on Antennas and Propagation, EUCAP 2011. Rome, 11-15 April 2011. - 9781457702501 ; , s. 1080-1084
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Konferensbidrag (refereegranskat)abstract
- A study is presented of the performance of microstrip filters packaged with Perfect Magnetic Conductor (PMC) and realization of the PMC using a lid of nails. A 3rd order parallel coupled-line bandpass filter is designed and packaged with a lid of nails at the Ku-band. The study shows the PMC packaging technique is very efficient in improving the filter characteristics including the insertion loss in the bandpass region.
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| 4. |
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| 5. |
- Pucci, Elena, 1982
(författare)
-
Characterization of losses in ridge, groove and microstrip gap waveguides
- 2011
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The gap waveguide is a new technology that recently has been presented as an attractive candidate for applications at millimeter and sub millimeter waves. The waveguide is generated in the gap between a smooth upper metal plate and a ridge (or a groove) in a textured lower metal plate. Thedifference compared to standard technologies, such as waveguides and microstrip transmission lines, is that the gap waveguide can be made of only metal and can support propagating TEM or TE/TM modes without need of metal contact between the assembled blocks. This is possible because the ridge is surrounded by an artificial magnetic conductor (AMC) that creates a parallel plate cut-off region and forces the field to be confined soley alongthe ridge. The AMC can simply be realized with a textured surface of metal pins, but other realizations are also possible. This thesis is focused on two main tasks. Firstly, to present an experimental study of losses in ridge and groove gap waveguides, and secondly to show thedesign, experimental validation and loss study of a new type of gap waveguide, called microstrip gap waveguide, for low frequency applications. The losses are determined by studying the unloaded Q-factor of resonators madein gap waveguide technology. The Q-factor is known to be a measure of the loss in a resonant circuit, and it can therefore also be used to determine loss per length unit of waveguide resonators. In this thesis different resonator designs are presented for ridge, groove and microstrip gap waveguides. The Q-factor is directly calculated from the simulated or measured transmission coefficient of the resonators. The attenuation per length unit can be easilyobtained from the Q-factor for TEM-type waveguides, and the ridge and microstrip gap waveguides are quasi-TEM. The simulation results have been validated by measurements. The obtained Q-factors approach values of 4200 for the ridge gap resonator and 6000 for the groove gap resonator, compared to an ideally realized rectangular waveguide that has a Q of 8000. The ideally realized rectangular waveguide has no air gaps between joining metal parts and this cannot easily be achieved at high frequency. Any gap, even ifit is very small, destroys performance of the rectangular waveguide, and its Q-factor. The advantage of the gap waveguides is that the AMC pin surface totally removes any leakage from gaps between the two metal plates. We alsopropose a new geometry made in microstrip gap waveguide, using a textured surface with mushroom-type electromagnetic bandgap (EBG) structure, to create the parallel-plate cut-off. This circuit represents a compact, low lossand already packaged solution, that can suppress cavity modes and radiations generated when packaging standard microstrip lines.Keywords: Gap waveguides, Artificial Magnetic Conductors, Mushroom-Type EBG, Losses, Quality Factor, Waveguide Resonators, Packaging of Microwave Components, Microstrip Lines.
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| 6. |
- Pucci, Elena, 1982, et al.
(författare)
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Contactless non-leaking waveguide flange realized by bed of nails for millimeter wave applications
- 2012
-
Ingår i: Proceedings of 6th European Conference on Antennas and Propagation, EuCAP 2012. Prague, 26-30 March 2012. - 9781457709180 ; , s. 3533-3536
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Konferensbidrag (refereegranskat)abstract
- Waveguide flanges are typically used to connect and measure high frequency circuits. When good conductive contact is not provided between the joining flange surfaces, currents will flow between them, and thereby causing leakage and losses affecting the circuit performance. This work presents a non-leaking contactless waveguide flange made with bed of nails. The flange does not need any contact when connected to another smooth flange, since the pins surface and the smooth surface together form a stopband suppressing any current and wave propagation between the two joining surfaces of the flanges.
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| 7. |
- Pucci, Elena, 1982, et al.
(författare)
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Design of a Dual-Mode Horn Element for Microstrip Gap Waveguide Fed Array
- 2013
-
Ingår i: 7th European Conference on Antennas and Propagation, EuCAP 2013, Gothenburg, Sweden, 8-12 April 2013. - 9781467321877 ; , s. 3086-3089
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Konferensbidrag (refereegranskat)abstract
- The low loss microstrip gap waveguide provides an easy and suitable solution to be used as feed network for antennas at high frequency. This paper presents the design of a slot coupled dual-mode horn element fed by microstrip gap waveguide for array applications at 60 GHz. The directive dual mode horn is used to reduce the grating lobes which are generated when the slot array elements have a distance bigger than lambda. Simulation results of the proposed design are presented in terms of return loss and grating lobe level.
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| 8. |
- Pucci, Elena, 1982, et al.
(författare)
-
Design of a four-element horn antenna array fed by inverted microstrip gap waveguide
- 2013
-
Ingår i: IEEE Antennas and Propagation Society, AP-S International Symposium (Digest). - 1522-3965. - 9781467353175 ; , s. 1226-1227
-
Konferensbidrag (refereegranskat)abstract
- The paper presents the design of a four-element slot coupled dual-mode horn array with microstrip gap waveguide as feed network. We present simulated results for return loss for the feed network both with and without the radiating horn array. We also compare results for two ways to generate the stopband of the parallel-plate modes: the ideal Perfect Magnetic Conductor used during the initial design, and the real bed of nails used in the practical realization. The study is performed at 60 GHz obtaining about 10% bandwidth.
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| 9. |
- Pucci, Elena, 1982, et al.
(författare)
-
Enhancing the efficiency of compact patch antennas composed of split ring resonators by using lumped capacitors
- 2012
-
Ingår i: IEEE Antennas and Wireless Propagation Letters. - 1548-5757 .- 1536-1225. ; 11, s. 1362-1365
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Tidskriftsartikel (refereegranskat)abstract
- A new type of small patch antenna with low profile and enhanced radiation efficiency is proposed in this letter. The antenna is realized with a double layer of low-permittivity material (polypropylene, εr = 2.2). The lower layer is used for the feeding of the antenna, and split ring resonators (SRRs) are printed on top of the upper layer acting as radiating elements. The compactness is provided by shorting the rings to the ground plane with two metal pins. Although this antenna presented initially a dual band of operation, it has been demonstrated how the use of a lumped capacitor in the inner ring can increase the total radiation efficiency of the antenna performing a single-band response. Therefore, when the two original operation frequency bands coincide, a manufactured prototype of the antenna demonstrated a measured radiation efficiency of 73% that can be provided at the operation frequency of 1.29 GHz.
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| 10. |
- Pucci, Elena, 1982, et al.
(författare)
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Evaluation of losses in microstrip gap waveguide for slot antennas applications
- 2012
-
Ingår i: IEEE Antennas and Propagation Society, AP-S International Symposium (Digest). - 1522-3965. - 9781467304627 ; , s. 1-2
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Konferensbidrag (refereegranskat)abstract
- The new microstrip gap waveguide supports a quasi-TEM mode in the air by the use of artificial magnetic conductors which force the field to travel in the air rather than in the substrate. This paper presents an evaluation of losses by measuring the Q-factor of a resonator made in this technology, made using a mushroom-type EBG surface. Losses are crucial when using printed circuits to feed slot antennas, thereby motivating this work. Comparisons with standard microstrip lines will be provided, showing promising results.
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| 11. |
- Pucci, Elena, 1982
(författare)
-
Gap Waveguide Technology for Millimeter Wave Applications and Integration with Antennas
- 2013
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The increasing advance of short range wireless communications requiring high data rates and the lack of available spectrum have driven researchers and industry to move towards higher frequencies, in particular to the millimeter wave range. The opening of this wide portion of free spectrum has risen a large interest in developing mm-wave communication systems for commercial applications. Higher frequencies lead to smaller sizes of RF components including antennas, thus introducing a new trend of realizing single compact modules, where active, passive components and antennas are integrated in the same package/chip. However, the implementation of passivecomponents and interconnected transmission lines on these modules is difficult at millimeter waves with classical technologies, such as microstrip transmission lines and waveguides. Microstrip transmission lines suffer fromhigh dielectric and conductive losses and waveguides are difficult to combine with integrated circuits and need accurate assembly process to assure good electrical contacts when made in different blocks. Therefore, new technologies are needed in order to face the challenges of the next generation systems.The new gap waveguide technology has been recently introduced as a promising candidate to address some of the problems faced at millimeter waves with conventional technologies. The key idea behind this circuit is based on the possibility to guide the electromagnetic field along desired directions in the gap between metal plates and to avoid any propagation along undesired directions.In this way, any leakage occurring in between the split blocks of a circuit with poor quality metal contacts as well as unwanted radiations are avoided. This condition is achieved by surrounding a metal ridge/strip, or groove, with a so-called Artificial Magnetic Conductor (AMC). When this textured layer is placed below an upper metal lid, all parallel-plate modes will be in cut-off, thus letting the propagation only in the air gap between the ridge/strip and the upper plate.This thesis presents the development of the gap waveguide in terms of packaging capability, losses, and integration with antennas. The losses study is performed by calculating the unloaded Q-factors of resonators made in ridge and groove gap waveguides. Experimental validations show that the gap waveguide has very low losses, and in particular the groove gap waveguide has similar measured unloaded Q-factors as rectangular waveguides when they are made in different blocks. The advantage is that the AMC surface inthe gap waveguide can remove any leakage from the tiny gaps between two metal plates, which is a benefit at high frequency. The losses study is also provided for micromachined gap waveguides above 200 GHz. In addition, the idea of a contactless waveguide flange made by bedof nails is presented for high frequency measurements. This new design can avoid typical mismatch and unwanted radiations which can occur in standard waveguide flanges when they are not well tightened to the circuit under test.We also present the packaging capabilities of the gap waveguide for low frequency applications, since the metal pins become too thick, by introducing a compact periodic surface made of printed zigzag wires.In particular, this thesis analyzes the microstrip gap waveguide, which becomes attractive for both low and high frequency applications because made in printed technology, but still allowing propagation in the air, thus beinglow loss. We also propose a new geometry made in microstrip gap waveguide, using a textured surface with mushroom-type electromagnetic bandgap (EBG) structure, to create the parallel-plate cut-off. This circuit represents a compact, low loss and already packaged solution, that can suppress cavity modes and radiations generated when packaging standard microstrip lines.Finally, the microstrip gap waveguide is applied as low loss feed network for horn antenna array. This thesis shows the design and experimental validation of a sixteen-element planar dual-mode horn array excited by a microstrip gapwaveguide corporate feed network, which can be an advantageous solution for 60 GHz antenna applications.
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| 12. |
- Pucci, Elena, 1982, et al.
(författare)
-
Losses in ridge gap waveguide compared with rectangular waveguide and microstrip lines
- 2010
-
Ingår i: EuCAP 2010 Fourth European Conference on Antennas and Propagation, Barcelona, 12-16 April 2010. - 9781424464319
-
Konferensbidrag (refereegranskat)abstract
- A study and quantification of losses in ridge gap waveguide, compared to losses in ideal standard rectangular waveguide and microstrip transmission line is presented. The study is performed by evaluating the quality factor of resonators made of ridge gap waveguide, rectangular waveguide and microstrip line. Results will show that the ridge gap waveguide has a very low loss.
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| 13. |
- Pucci, Elena, 1982, et al.
(författare)
-
New low loss inverted microstrip line using gap waveguide technology for slot antenna applications
- 2011
-
Ingår i: Proceedings of the 5th European Conference on Antennas and Propagation, EUCAP 2011. Rome, 11-15 April 2011. - 9788882020743 ; , s. 979-982
-
Konferensbidrag (refereegranskat)abstract
- Recently, a new transmission line concept, called gap-waveguide, has been introduced. This technology generates a quasi-TEM mode in the gap between parallel metal plates and prohibits all other modes to propagate by making use of artificial magnetic conductors (AMCs) in the forms of e.g. lid of nails or mushrooms-type EBG surfaces. It has been shown how such geometry can replace standard microstrip lines and waveguides since it needs neither dielectric nor metal joints, being then an advantageous alternative that can be used for several applications at high frequency. This paper shows how the gap waveguide can also be realized in printed technology creating a new type of inverted microstrip line, called microstrip gap waveguide, which has low loss and large bandwidths can be achieved.
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| 14. |
- Pucci, Elena, 1982, et al.
(författare)
-
New Microstrip Gap Waveguide on Mushroom-Type EBG for Packaging of Microwave Components
- 2012
-
Ingår i: IEEE Microwave and Wireless Components Letters. - 1558-1764 .- 1531-1309. ; 22:3, s. 129-131
-
Tidskriftsartikel (refereegranskat)abstract
- The gap waveguide has been recently presented as a new transmission line technology using artificial magnetic conductors (AMCs) to allow the wave propagation only along a desired path. The first validation has been provided using a lid of metal pins as AMC for high frequency applications. In this letter, simulations and measurement results are presented for another version called microstrip gap waveguide, working as inverted microstrip line and realized using a mushroom-type EBG surface. The transmission line is surrounded by mushrooms which create a parallel plate stop band, suppressing cavity modes and unwanted radiations compared to standard packaged microstrip transmission lines. The field propagates in the air gap between the upper lid and the mushrooms layer, providing a low loss compact circuit made in printed technology.
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| 15. |
- Pucci, Elena, 1982, et al.
(författare)
-
Planar Dual-Mode Horn Array with Corporate-Feed Network in Inverted Microstrip Gap Waveguide
- 2014
-
Ingår i: IEEE Transactions on Antennas and Propagation. - 0018-926X .- 1558-2221. ; 62:7, s. 3534 - 3542
-
Tidskriftsartikel (refereegranskat)abstract
- The gap waveguide technology was recently introduced as an alternative to hollow waveguides and substrate integrated waveguides for millimeter-wave applications. This paper presents the design of a 4 x 4 planar dual-mode horn array with low loss corporate feed network realized by using an inverted microstrip gap waveguide. The dual-mode horns are compact and designed to reduce the power losses in grating lobes. It is because the diameters of the horn apertures are larger than two wavelengths to allow more space for the feed network and thereby lower conductive losses. The measurements show very good agreement with simulations, with 10% bandwidth of the return loss, 25 dBi realized gain and about 60% aperture efficiency.
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| 16. |
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| 17. |
- Pucci, Elena, 1982, et al.
(författare)
-
Study of Q-Factors of Ridge and Groove Gap Waveguide Resonators
- 2013
-
Ingår i: IET Microwaves, Antennas and Propagation. - : Institution of Engineering and Technology (IET). - 1751-8725 .- 1751-8733. ; 7:11, s. 900-908
-
Tidskriftsartikel (refereegranskat)abstract
- The gap waveguide technology for millimeter waves applications has been recently presented. The new structure is made by generating a parallel plate cut-off region between an artificial magnetic conductor (AMC) and a metallic plate. Propagating waves will be only allowed to follow a metal ridge or groove surrounded by the AMC. The gap waveguide can be made of only metal and does not need any contact between the metal joints compared to standard waveguides. In this study, a study of Q-factors of resonators made in ridge and groove gap waveguides are presented. The resonators are made of copper and the AMC used is a textured surface of metallic pins. Simulated and measured unloaded Qs are presented and compared with Q of a standard rectangular waveguide. High Q-factors are measured for the prototypes presented, approaching 90-96% of the simulated values. Furthermore, it is shown how the lid of pins can easily stop the leakage loss at the joints of the circuit, which is the typical cause of reduced Q-factor of standard waveguides at high frequency.
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| 18. |
- Quevedo Teruel, Oscar, et al.
(författare)
-
Compact loaded PIFA for multifrequency applications
- 2010
-
Ingår i: IEEE Transactions on Antennas and Propagation. - 0018-926X .- 1558-2221. ; 58:3, s. 656-664
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Tidskriftsartikel (refereegranskat)abstract
- A new multifrequency microstrip patch antenna is presented. The antenna can be considered a PIFA since it has a metallic wall on one of its sides. The different bands of operation are independent of each other, and different radiation patterns for each band can be achieved if desired. In addition, a circuital model is introduced to explain the operation of the antenna. This model presents some similarities with composite right left handed models presented in the literature. Some prototypes have been manufactured and measurements of return losses, efficiencies and radiation patterns, have been performed for a thorough characterization of the antenna as well as to validate the simulation results.
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| 19. |
- Quevedo Teruel, Oscar, et al.
(författare)
-
On the Increase of the Efficiency and Bandwidth of Compact PIFAs based on SRR by Making Use of Lumped Capacitors
- 2010
-
Ingår i: 2010 IEEE International Symposium on Antennas and Propagation, Toronto, July 11-17, 2010. - 1522-3965. - 9781424449675
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Konferensbidrag (refereegranskat)abstract
- In this communication, a new compact microstrip patch antenna based on shortcircuited SRRs is presented. This design, in its basic version, provides a dual band response. This initial configuration will be modified by making use of lumped elements (capacitors), in order to achieve a single band with large bandwidth or higher radiation efficiency.
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| 20. |
- Rahiminejad, Sofia, 1987, et al.
(författare)
-
100 GHz SOI gap waveguides
- 2013
-
Ingår i: 2013 Transducers and Eurosensors XXVII. - 9781467359818 ; , s. 510-513
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Konferensbidrag (refereegranskat)abstract
- Two gap waveguide technologies, groove and ridge, are presented here for F-band applications. Three different groove gap waveguide devices and four different ridge gap waveguide devices have been fabricated. All of them were micromachined to achieve the feature size required for the frequency band and fabricated in a single process using SOI wafers. The two types provide a more robust coupling to standard waveguides and high frequency probes. Measurements for most of the devices are shown in this paper, showing robust measurements and good agreement with simulations. More measurements need to be done but the initial ones show the promise both in the manufacturing technique and the coupling.
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| 21. |
- 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-
-
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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| 22. |
- Rahiminejad, Sofia, 1987, et al.
(författare)
-
Contactless pin-flange adapter for high-frequency measurements
- 2012
-
Ingår i: 23rd Micromechanics and Microsystems Europe Workshop, MME 2012, September 9 - 12, 2012, Ilmenau, Germany.
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Konferensbidrag (refereegranskat)abstract
- We present a first contactless pin-flange adapter for high-frequency measurements based on gap waveguide technology. Conventionally, standard (WR) flanges are used, these require good electrical contact and are sensitive to small gaps. The pin-flange adapter has been fabricated and demonstrated for the frequency range 220-325 GHz. It shows similar or better results than a standard flange or a choke flange without requiring electrical contact. The pin-flange adapter has a lower noise level compared to the other flanges, almost 10 dB lower.
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| 23. |
- Rahiminejad, Sofia, 1987, et al.
(författare)
-
Design of micromachined ridge gap waveguides for millimeter-wave applications
- 2011
-
Ingår i: Procedia Eng.. - : Elsevier BV. ; 25, s. 519-522
-
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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| 24. |
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| 25. |
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| 26. |
- Rahiminejad, Sofia, 1987, et al.
(författare)
-
MICORMACHINED MULTILAYER SU8 DOUBLE-SIDED PIN-FLANGE ADAPTER FOR 220-325 GHZ
- 2014
-
Ingår i: 25th Micromechanics and Microsystems Europe Workshop, MME 2014, Istanbul, Turkey, August 31 - September 3, 2014.
-
Konferensbidrag (refereegranskat)abstract
- We present the first double-sidedpin-flange adapter for 220 ? 325 GHz solely madeout of gold covered multilayered SU8. The processis based on exposing layers with different patternsrealizing openings through both layers and pinstructures in only one of the layers. Each processgives two layers which are then bonded back toback resulting in a four layer device. SU8 has thebenefit of being cheap and robust compared to Siand is useful for applications where the device willbe handled by hand and could be exposed to unevenforces. The multilayer SU8 double-sided pin-flangeadapter was successfully fabricated. Measurementsand evaluations will be presented at the conference.
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| 27. |
- Rahiminejad, Sofia, 1987, et al.
(författare)
-
Micromachined contactless pin-flange adapter for robust high-frequency measurements
- 2014
-
Ingår i: Journal of Micromechanics and Microengineering. - : IOP Publishing. - 1361-6439 .- 0960-1317. ; 24:8, s. Art. no. 084004-
-
Tidskriftsartikel (refereegranskat)abstract
- We present the first micromachined double-sided contactless WR03 pin-flange adapter for 220-325 GHz based on gap waveguide technology. The pin-flange adapter is used to avoid leakage at the interface of two waveguides even when a gap between them is present and can be fitted onto any standard WR03 waveguide flange. Tolerance measurements were performed with gaps ranging from 30-100 mu m. The performance of the micromachined pin flange has been compared to a milled pin flange, a choke flange and to standard waveguide connections. The micromachined pin flange is shown to have better performance than the standard connection and similar performance to the milled pin flange and choke flange. The benefits of micromachining over milling are the possibility to mass produce pin flanges and the better accuracy in the 2D design. Measurements were performed with and without screws fixing the flanges. The flanges have also been applied to measure two devices, a straight rectangular waveguide of 1.01 inch and a ridge gap resonator. In all cases, the micromachined pin flange performed flawlessly while the standard flange experienced significant losses at already small gaps.
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| 28. |
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| 29. |
- Rahiminejad, Sofia, 1987, et al.
(författare)
-
Micromachined gap waveguide devices for above 100 GHz
- 2014
-
Ingår i: Swedish Microwave Days March 11-12, 2014.
-
Konferensbidrag (refereegranskat)abstract
- Gap waveguide technology is a fundamentally new highfrequencywaveguide technology [1]. It does not need anyelectrical contact between the split blocks which gives it anadvantage, compared to the rectangular waveguide.Rectangular waveguides are often fabricated by milling.However there are issues with milling when constructingwaveguides above 100 GHz. MEMS technology can offerhigh-precision fabrication and thus enables the path for newtypes of high-frequency components. An overview of themicromachined gap waveguide devices that has beenfabricated for above 100 GHz are presented here.
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| 30. |
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| 31. |
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| 32. |
- Rahiminejad, Sofia, 1987, et al.
(författare)
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Micromachined Ridge Gap Waveguide and Resonator for Millimeter-Wave Applications
- 2012
-
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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| 33. |
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| 34. |
- Rahiminejad, Sofia, 1987, et al.
(författare)
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Pin-Flange Adapters for High Frequency Measurements
- 2015
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Ingår i: 18th International Conference on Solid-State Sensors, Actuators and Microsystems Transducers 2015 June 21-25, 2015.
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)
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| 35. |
- Rahiminejad, Sofia, 1987, et al.
(författare)
-
Polymer Gap Adapter for Contactless, Robust, and Fast Measurements at 220-325 GHz
- 2016
-
Ingår i: Journal of Microelectromechanical Systems. - : Institute of Electrical and Electronics Engineers (IEEE). - 1057-7157 .- 1941-0158. ; 25:1, s. 160-169
-
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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| 36. |
- Rahiminejad, Sofia, 1987, et al.
(författare)
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SU8 Ridge Gap Resonator
- 2013
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Ingår i: MEMSWAVE, 2013, Potsdam, Germany.
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Konferensbidrag (refereegranskat)
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| 37. |
- Rahiminejad, Sofia, 1987, et al.
(författare)
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SU8 ridge-gap waveguide resonator
- 2014
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Ingår i: International Journal of Microwave and Wireless Technologies. - : Cambridge University Press (CUP). - 1759-0787 .- 1759-0795. ; 6:5, s. 459-465
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Tidskriftsartikel (refereegranskat)abstract
- In this paper, we present the first ridge-gap waveguide resonator made with a polymer base. It is designed for the frequency range 220-325 GHz, and is fabricated solely using a Au coated two-layer SU8-based process. The design is based on previous work done with Si. The new process has advantages such as fewer and cheaper process steps. The SU8 ridge-gap waveguide resonator is made in order to obtain attenuation characteristics via the measured Q-factor of the resonator. The ridge-gap waveguide resonator has the same dimensions as the previous one fabricated in Si, and the same thickness of the Au coating. The SU8-based resonator shows an attenuation loss of 0.41 dB/mm at 282.2 GHz compared to the Si-based resonator with an attenuation loss of 0.043 dB/mm at 283.5 GHz. This makes the SU8 process a more cost-effective alternative to the Si process
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| 38. |
- Rajo, Eva, 1972, et al.
(författare)
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Suppression of Parallel Plate Modes in Low Frequency Microstrip Circuit Packages Using Lid of Printed Zigzag Wires
- 2013
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Ingår i: IEEE Microwave and Wireless Components Letters. - : Institute of Electrical and Electronics Engineers (IEEE). - 1558-1764 .- 1531-1309. ; 23:7, s. 359-361
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Tidskriftsartikel (refereegranskat)abstract
- This work deals with the suppression of parallel plate and cavity modes in shielded microstrip circuits operating at the lower microwave frequency range. The suppression is achieved by using a lid made of zigzag wires printed periodically on narrow slices of ungrounded circuit boards, located vertically side by side. This structure is very compact both in periodicity and height, it suppresses cavity modes over about an octave 2: 1 bandwidth, and it does not interfere with the packaged microstrip circuit.
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| 39. |
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| 40. |
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