| 1. |
- Abele, H., et al.
(author)
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Particle physics at the European Spallation Source
- 2023
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In: Physics reports. - : Elsevier. - 0370-1573 .- 1873-6270. ; 1023, s. 1-84
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Research review (peer-reviewed)abstract
- Presently under construction in Lund, Sweden, the European Spallation Source (ESS) will be the world’s brightest neutron source. As such, it has the potential for a particle physics program with a unique reach and which is complementary to that available at other facilities. This paper describes proposed particle physics activities for the ESS. These encompass the exploitation of both the neutrons and neutrinos produced at the ESS for high precision (sensitivity) measurements (searches).
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| 2. |
- Burgman, A., et al.
(author)
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The ESSnuSB Design Study: Overview and Future Prospects
- 2023
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In: Universe. - : MDPI. - 2218-1997. ; 9:8
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Research review (peer-reviewed)abstract
- ESSnuSB is a design study for an experiment to measure the CP violation in the leptonic sector at the second neutrino oscillation maximum using a neutrino beam driven by the uniquely powerful ESS linear accelerator. The reduced impact of systematic errors on sensitivity at the second maximum allows for a very precise measurement of the CP violating parameter. This review describes the fundamental advantages of measurement at the second maximum, the necessary upgrades to the ESS linac in order to produce a neutrino beam, the near and far detector complexes, and the expected physics reach of the proposed ESSnuSB experiment, concluding with the near future developments aimed at the project realization.
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| 3. |
- Burgman, A., et al.
(author)
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The European Spallation Source neutrino super-beam conceptual design report
- 2022
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In: The European Physical Journal Special Topics. - : Springer Nature. - 1951-6355 .- 1951-6401. ; 231:21, s. 3779-3955
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Research review (peer-reviewed)abstract
- A design study, named ESSνSB for European Spallation Source neutrino Super Beam, has been carried out during the years 2018–2022 of how the 5 MW proton linear accelerator of the European Spallation Source under construction in Lund, Sweden, can be used to produce the world’s most intense long-baseline neutrino beam. The high beam intensity will allow for measuring the neutrino oscillations near the second oscillation maximum at which the CP violation signal is close to three times higher than at the first maximum, where other experiments measure. This will enable CP violation discovery in the leptonic sector for a wider range of values of the CP violating phase δCPδCP and, in particular, a higher precision measurement of δCPδCP. The present Conceptual Design Report describes the results of the design study of the required upgrade of the ESS linac, of the accumulator ring used to compress the linac pulses from 2.86 ms to 1.2 μs, and of the target station, where the 5 MW proton beam is used to produce the intense neutrino beam. It also presents the design of the near detector, which is used to monitor the neutrino beam as well as to measure neutrino cross sections, and of the large underground far detector located 360 km from ESS, where the magnitude of the oscillation appearance of νe from νμ is measured. The physics performance of the ESSνSB research facility has been evaluated demonstrating that after 10 years of data-taking, leptonic CP violation can be detected with more than 5 standard deviation significance over 70% of the range of values that the CP violation phase angle δCPδCP can take and that δCPδCP can be measured with a standard error less than 8° irrespective of the measured value of δCPδCP. These results demonstrate the uniquely high physics performance of the proposed ESSνSBESSνSB research facility.
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| 4. |
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| 5. |
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| 6. |
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| 7. |
- Aziz, Imran, et al.
(author)
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28 GHz Circular Polarized Fan-out Antenna Array with Wide-angle Beam-steering
- 2022
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In: International Journal of RF and Microwave Computer-Aided Engineering. - : Hindawi Publishing Corporation. - 1096-4290 .- 1099-047X. ; 32:3
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Journal article (peer-reviewed)abstract
- The article presents 28 GHz circular polarized antenna arrays designed in an embedded wafer level ball grid array (eWLB) package for 5G applications. The antenna arrays are realized on a re-distribution layer (RDL) in the fan-out region of the chip package. Two separate but identical arrays perform RX and TX operations where a crossed dipole is used as a building block of the array. These 4-element arrays have <−10 dB impedance bandwidth covering 25.3–29.8 GHz (4.5 GHz bandwidth) while presenting 10 dBi maximum realized gain. The measurement results show <3 dB axial ratio in the band 26–29.5 GHz, and the main beam can be steered in ±50° in the azimuth plane when array elements are fed by appropriate phases from the chip. The radio frequency module provides 31 dBm maximum equivalent isotropic radiated power (EIRP).
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| 8. |
- Aziz, Imran, et al.
(author)
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28 GHz compact dipole antenna array integrated in fan-out eWLB package
- 2022
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In: International journal of microwave and wireless technologies. - : Cambridges Institutes Press. - 1759-0795 .- 1759-0787. ; 14:10, s. 1369-1377
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Journal article (peer-reviewed)abstract
- In this paper, we present a 28 GHz antenna array in package which covers the n257 and n258 frequency bands designated for 5G applications. The dipole antenna array is placed on one of the two re-distribution layers in the fan-out eWLB (embedded Wafer Level Ball Grid Array) package. For TX and RX, separate but identical antenna arrays are placed on each side of the die. The paper presents a novel horn-shaped heatsink which not only dissipates the heat, but also improves the radiation performance. The four-elements dipole array has the impedance bandwidth of almost 6 GHz (24–30 GHz) and shows a maximum realized gain of 9.5 dBi. Beam-steering in ± 35 deg is achieved in the azimuth plane (H-plane) by providing different phases to the dipoles through the chip. The measurements nicely agree with the simulation results.
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| 9. |
- Aziz, Imran, et al.
(author)
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60 GHz compact broadband antenna arrays with wide-angle beam steering
- 2019
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In: The Journal of Engineering. - : INST ENGINEERING TECHNOLOGY-IET. - 2051-3305. ; :8, s. 5407-5414
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Journal article (peer-reviewed)abstract
- Highly integrated multilayered printed circuit board-based patch antenna arrays are proposed in this study for 60 GHz wireless communications. Electromagnetic coupling between two stacked patches is used to achieve the broadband performance. Different structures of single element antennas, two-element antenna arrays and four-element antenna arrays are presented. The two compact four-element antenna arrays show < -10 dB impedance bandwidth of 13 and 14.6% with 12 dBi peak gain. The arrays have the 3 dB gain bandwidth of 9 and 13%. A single column, four-element sub-array is used to design 4 x 16 antenna array. This array delivers 20.8 dBi peak gain with 13% impedance and gain bandwidth. Furthermore, a two-element series fed array is used to realise a 2 x 16 phased antenna array. This array is fed through a 16 x channel radio frequency IC to achieve the beam steering in +/- 50 degrees range.
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| 10. |
- Aziz, Imran, et al.
(author)
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60 GHz RF module with beam-steering optimization algorithm for high data rate access and backhaul communications
- 2022
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In: EURASIP Journal on Wireless Communications and Networking. - : Springer Nature. - 1687-1472 .- 1687-1499. ; 2022:1
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Journal article (peer-reviewed)abstract
- This paper presents an 802.11ad-based radio frequency module for high data rate fixed wireless access and backhaul communications. The transceiver chip is manufactured in SiGe BiCMOS technology covering 57-71 GHz, providing 16 RX and 16 TX paths with combined output power of more than 20 dBm. The chip is packaged using embedded wafer-level BGA technology of the size 12.6 x 12.6 x 0.8 mm (3) and employs advanced dielectric materials with 2 metallic redistribution layers. The package integrates the transceiver chip with RX and TX high gain PCB antenna arrays, allowing effective isotropic radiated power (EIRP) of more than 40 dBm. Beam steering is achieved in +/- 50(o) by the transceiver through providing appropriate weights to the antenna arrays. The paper presents generation of beamforming lookup table along with optimization of the power distribution to the array. This optimization results in flattening of the EIRP over the whole beam-steering range and frequency bandwidth. The module allows for data rates up to 10 Gbps by employing full- channel 128 QAM and half-channel 256 QAM single-carrier modulation.
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| 11. |
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| 12. |
- Aziz, Imran, et al.
(author)
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Broadband Fan-out Phased Antenna Array at 28 GHz for 5G Applications
- 2020
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In: Proceedings of the 50th European Microwave Conference. - 9782874870590 - 9782874870583 - 9781728170398 ; , s. 212-215
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Conference paper (peer-reviewed)abstract
- In this paper we present a 28 GHz antenna in package (AiP) design for 5G applications. The antenna array is placed in the fan-out region of the eWLB (enhanced Wafer Level Ball Grid Array) package. Separate antenna arrays are used for TX and RX, which are placed on one of the two re-distribution layers (RDL) inside the package. The heatsink required for the chip operation is also used as a horn antenna to improve the design performance. The 4-element dipole array has the impedance bandwidth of almost 6 GHz (24 GHz-30 GHz) and gives a maximum gain of 9.5 dBi. Beam-steering in ± 35 deg is achieved in the azimuthal plane (H-plane) by providing different phases to the dipoles through the chip.
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| 13. |
- Aziz, Imran, et al.
(author)
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Connected Slots Antenna Array Feeding the High Gain Lens for Wide-angle Beam-steering Applications
- 2022
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In: International journal of microwave and wireless technologies. - 1759-0795 .- 1759-0787. ; 14:1, s. 77-85
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Journal article (peer-reviewed)abstract
- This paper presents a 60 GHz connected slots linear-phased array feeding a high-gain semi-symmetric lens antenna. This design provides high gain, broadband, and beam-steering capabilities for gigabit rate access and backhaul communications. The connected slots antenna array (CSAA) is excited at 16× equidistant points which not only yields spatial power combining but also allows the progressive phase changes to steer the beam in ±45° in azimuth plane. To characterize the CSAA-fed lens antenna, four different power splitters are fabricated which steer the main beam in 0, 15, 30, and 45°. The lens is designed in a way to overcome the scan loss and get comparatively higher gain when beam is steered away from the broadside. The measured results show 25.4 dBi maximum gain with 3 dB gain bandwidth covering the full band 57–66 GHz whereas 3 dB beam-steering range is ±45° for all frequencies. Besides, the half power beamwidth is 6 and 10° in elevation (E-plane) and azimuth plane (H-plane), respectively.
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| 14. |
- Aziz, Imran, et al.
(author)
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Effects of proton irradiation on 60 GHz CMOS transceiver chip for multi-Gbps communication in high-energy physics experiments
- 2019
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In: The Journal of Engineering. - : INST ENGINEERING TECHNOLOGY-IET. - 2051-3305. ; :8, s. 5391-5396
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Journal article (peer-reviewed)abstract
- This article presents the experimental results of 17 MeV proton irradiation on a 60 GHz low power, half-duplex transceiver (TRX) chip implemented in 65 nm CMOS technology. It supports short range point-to-point data rate up to 6 Gbps by employing on-off keying (OOK). To investigate the irradiation hardness for high-energy physics (HEP) applications, two TRX chips were irradiated with total ionising doses (TID) of 74 and 42 kGy and fluence of 1.4 x 10(14)N(eq)/cm(2) and 0.8 x 10(14)N(eq)/cm(2) for RX and TX modes, respectively. The chips were characterised by pre- and post-irradiation analogue voltage measurements on different circuit blocks as well as through the analysis of wireless transmission parameters like bit error rate (BER), eye diagram, jitter etc. Post-irradiation measurements have shown certain reduction in performance but both TRX chips have been found operational through over the air measurements at 5 Gbps. Moreover, very small shift in the carrier frequency was observed after the irradiation.
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| 15. |
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| 16. |
- Aziz, Imran, et al.
(author)
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High Gain Compact 57-66 GHz Antenna Array for Backhaul & Access Communications
- 2018
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In: 12th European Conference on Antennas and Propagation (EuCAP 2018). - : Institution of Engineering and Technology. - 9781785618161
-
Conference paper (peer-reviewed)abstract
- Highly integrated multilayered patch antenna arrays are proposed in this paper for 60 GHz wireless communications. Electromagnetic coupling between two stacked patches is used for improving the broadband performance. Three different structures of single column 4-element arrays are presented with center and corporate feeding networks. Maximum gain of 12.2 dBi and <-10 dB return loss in the entire unlicensed frequency band 57-66 GHz is measured. Furthermore, a compact 4×16 antenna array (41 mm x 13 mm) is presented with 18.7 dBi maximum gain, 8 GHz (5765) bandwidth and 7° HPBW (half power beam width) in H plane.
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| 17. |
- Aziz, Imran
(author)
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Ultra-wideband Millimeter-wave Antenna Arrays and Front-end Systems : For high data rate 5G and high energy physics applications
- 2021
-
Doctoral thesis (other academic/artistic)abstract
- The demand for wireless data communications is rapidly increasing due to several factors including increased internet access, increasingly growing number of mobile users and services, implementation of the Internet of Things (IoT), high-definition (HD) video streaming and video calling. To meet the bandwidth requirement of new and emerging applications, it is necessary to move from the existing microwave bands towards millimeter-wave bands. This thesis presents different antenna arrays at 60 GHz and 28 GHz that are integrated with the front-end RFIC to steer the beam in ≈ ±50° in the azimuth plane. The 5G antenna arrays at 28 GHz are designed to provide broadband high data rate services to the end users. In order to transport this high-volume data to the core network, a fixed wireless access (FWA) link demands the implementation of a broadband, high gain and steerable narrow-beam array. The 60 GHz antenna arrays, presented in this thesis, are good candidates for both FWA as well as backhaul communications. The two proposed arrays at 60 GHz (57-66 GHz) are i) a stacked patches array and ii) a connected slots array feeding a high gain lens antenna. The 2×16 stacked patches antenna array shows more than 20 dBi realized gain. The array is integrated with the front-end RFIC and the resulting module shows > 40 dBm measured effective isotropic radiated power (EIRP). The other 60 GHz antenna array is designed as linear connected slots with sixteen equidistant feeding points. The latest is then used as a feeder of a high gain dielectric lens. Peak measured gain of 25.4 dBi is achieved with this antenna. Moreover, instead of experiencing scan loss, the lens is designed to get higher gain when the beam is steered away from the broadside direction.Furthermore, two compact antenna arrays are designed at 28 GHz (24.25 - 29.50 GHz). A linear polarized (LP) and a circular polarized (CP) array are realized in the fan-out embedded wafer level ball-grid-array (eWLB) package. In comparison with the PCB arrays, this antenna in package (AiP) solution is not only cost-effective but it also reduces the integration losses because of shorter feed lines and no geometrical discontinuity. The LP array is realized as a dipole antenna array feeding a novel horn-shaped heatsink. The RF module gives 34 dBm peak EIRP with beam-steering in ±35°. Besides, the CP antenna array is realized with the help of crossed dipoles and the RF module provides 31 dBm peak EIRP with beam-steering in ±50°.The data demands are not limited to the telecom industry as the upgradation of accelerators and experiments at the large hadron collider (LHC) at CERN will result in increased event rate thus demanding higher data rate front-end readout systems. This work thus investigates the feasibility of 60 GHz wireless links for the data readout at CERN. For this purpose, the 60 GHz wireless chips are irradiated with 17 MeV protons [dose 7.4 Mrad (RX) & 4.2 Mrad (TX)] and 200 MeV electrons [dose 270 Mrad (RX) & 314 Mrad (TX)] in different episodes. The chips have been found operational in the post-irradiation investigations with some performance degradation. The encouraging results motivate to move forward and investigate the realization of wireless links in such a complex environment.
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| 18. |
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| 19. |
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| 20. |
- Bhattacharyya, Anirban, et al.
(author)
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ESS RF Source and Spoke Cavity Test Plan
- 2015
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Reports (other academic/artistic)abstract
- This report describes the test plan for the first high power RF source, ESS prototype double spoke cavity and ESS prototype cryomodule at the FREIA Laboratory.
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| 21. |
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| 22. |
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| 23. |
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| 24. |
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| 25. |
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| 26. |
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| 27. |
- Dancila, Dragos, et al.
(author)
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A compact 10 kW solid-state RF power amplifier at 352 MHz
- 2017
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In: Journal of Physics, Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 874
-
Journal article (peer-reviewed)abstract
- A compact 10 kW RF power amplifier at 352 MHz was developed at FREIA for the European Spallation Source, ESS. The specifications of ESS for the conception of amplifiers are related to its pulsed operation: 3.5 ms pulse length and a duty cycle of 5%. The realized amplifier is composed of eight kilowatt level modules, combined using a planar Gysel 8-way combiner. The combiner has a low insertion loss of only 0.2 dB, measured at 10 kW peak power. Each module is built around a commercially available LDMOS transistor in a single-ended architecture. During the final tests, a total output peak power of 10.5 kW was measured.
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| 28. |
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| 29. |
- Dancila, Dragos
(author)
-
A microfabricated sensor and a method of detecting a component in bodily fluid
- 2015
-
Patent (pop. science, debate, etc.)abstract
- The invention relates to a microfabricated sensor (1 ) for detecting a component in bodily fluid, comprising; an inlet means (2) for receiving a sample of bodily fluid, a fluid cavity (6) connected to the inlet means for receiving the sample of bodily fluid from the inlet means, and an RF resonant cavity (13), delimited by walls (14). At least one of the walls forms a separating wall (15), separating the fluid cavity from the RF resonant cavity, wherein the separating wall is configured such that the dielectric properties of the bodily fluid in the fluid cavity provide an influence on the electromagnetic properties of the RF resonant cavity.
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| 30. |
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| 31. |
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| 32. |
- Dancila, Dragos, et al.
(author)
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Antennas on Paper Using Ink-Jet Printing of Nano-Silver Particles for Wireless Sensor Networks in Train Environment
- 2016
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In: Microwave and optical technology letters (Print). - : Wiley. - 0895-2477 .- 1098-2760. ; 58:4, s. 754-759
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Journal article (peer-reviewed)abstract
- This paper presents the design, manufacturing and measurements of antennas on paper, realized using ink-jetprinting of conductive inks based on nano-silver particles (nSPs). The extraction of the substrate characteristicssuch as the dielectric constant and dielectric loss is performed using a printed ring resonator technique. Thecharacterization of the nSPs conductive inks assesses different parameters as sintering time and temperature.Two antennas are realized corresponding to the most common needs for Wireless Sensor Networks (WSN) inTrains Environment. The first one is a patch antenna characterized by a broadside radiation pattern and suitedfor operation on metallic structures. The second one is a quasi-yagi antenna, with an end fire radiation patternand higher directivity, without requiring a metallic ground plane. Both antennas present a good matching (S11 < -20 dB and S11 < -30 dB, respectively) and acceptable efficiency (55 % and 45 %, respectively) for the papersubstrate used at the center frequency of 2.4 GHz, corresponding to the first channel of the IEEE 802.15.4 band.
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| 33. |
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| 34. |
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| 35. |
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| 36. |
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| 37. |
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| 38. |
- Dancila, Dragos, et al.
(author)
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Differential Microstrip Patch Antenna as Feeder of a Hyper-Hemispherical Lens for F-Band MIMO Radars
- 2016
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In: 2016 GLOBAL SYMPOSIUM ON MILLIMETER WAVES (GSMM) & ESA WORKSHOP ON MILLIMETRE-WAVE TECHNOLOGY AND APPLICATIONS. - 9781509013487 - 9781509013494 ; , s. 103-106
-
Conference paper (peer-reviewed)abstract
- In this paper, a novel differential microstrip patch antenna (DMPA) is designed and used to feed a lens antenna for short range F-band MIMO radars. The DMPA is fed differentially by a pair of coupled lines. The antenna is connected via a differential impedance matching network to the differential output of the modules, eliminating this way the need of a balun in the RF frontend. The simulated antenna gain is about 8 dBi and bandwidth (S11 < -10 dB) is between 125 - 137 GHz. Preliminary experimental measurements are shown using Transmit/Receive modules in 0.13 μm SiGe:C BiCMOS technology, hybrid connected using wirebonding to off chip DMPAs. It is shown by the transmission link evaluation that the gain is increased by about 15 dBi adding a 10 mm radius 3D printed polyamide lens in the near field of the DMPA.
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| 39. |
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| 40. |
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| 41. |
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| 42. |
- Dancila, Dragos, et al.
(author)
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Leaky Wave Antenna at 300 GHz in Silicon Micromachined Waveguide Technology
- 2019
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In: 2019 44th International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz). - : IEEE. - 9781538682852 - 9781538682869
-
Conference paper (peer-reviewed)abstract
- A leaky wave antenna composed of eight slots in a gold metallised silicon micromachined waveguide was designed, fabricated and measured at 300 GHz. The measured results are in good agreement with the simulations.
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| 43. |
- Dancila, Dragos, et al.
(author)
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Low Phase Noise Oscillator at 60 GHz Stabilized bya Substrate Integrated Cavity Resonator in LTCC
- 2014
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In: IEEE Microwave and Wireless Components Letters. - 1531-1309 .- 1558-1764. ; 24:12, s. 887-889
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Journal article (peer-reviewed)abstract
- In this letter, we report a low phase noise oscillatorexhibiting state-of-the-art phase noise characteristics at 60 GHz.The oscillator is stabilized by an off-chip substrate integratedwaveguide (SIW) cavity resonator, manufactured in LTCC technology.The area on top of the cavity resonator is used to flip-chipmount the MMIC, realized in SiGe technology. Measured oscillatorsdiscussed in this paper operate at frequencies of 59.91,59.97, and 59.98 GHz. The measured phase noise at 1 MHzoffset is 115.76 dBc/Hz, 115.92 dBc/Hz and 116.41 dBc/Hz,respectively. To our knowledge, the present hybrid oscillator hasthe lowest phase noise and highest figure of merit of integratedoscillators at V-band. The simulations are in very good agreementwith the measured oscillation frequencies.
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| 44. |
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| 45. |
- Dancila, Dragos, et al.
(author)
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Micromachined Cavity Resonator Sensors for on Chip Material Characterisation in the 220–330 GHz band
- 2017
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In: Proceedings of the 47th European Microwave Conference, Nuremberg, October 8-13, 2017. - : Institute of Electrical and Electronics Engineers (IEEE). - 9782874870477 - 9781538639641 ; , s. 938-941
-
Conference paper (peer-reviewed)abstract
- A silicon micromachined waveguide on-chip sensor for J-band (220-325 GHz) is presented. The sensor is based on a micromachined cavity resonator provided with an aperture in the top side of a hollow waveguide for sensing purposes. The waveguide is realized by microfabrication in a silicon wafer, goldmetallized and assembled by thermocompression bonding. The sensor is used for measuring the complex relative permittivity of different materials. Preliminary measurements of several dielectric materials are performed, demonstrating the potential of the sensor and methodology.
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| 46. |
- Dancila, Dragos, et al.
(author)
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Millimeter wave silicon micromachined waveguide probe as an aid for skin diagnosis - results of measurements on phantom material with varied water content
- 2014
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In: Skin research and technology. - : Wiley. - 0909-752X .- 1600-0846. ; 20:1, s. 116-123
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Journal article (peer-reviewed)abstract
- BackgroundMore than 2 million cases of skin cancer are diagnosed annually in the United States, which makes it the most common form of cancer in that country. Early detection of cancer usually results in less extensive treatment and better outcome for the patient. Millimeter wave silicon micromachined waveguide probe is foreseen as an aid for skin diagnosis, which is currently based on visual inspection followed by biopsy, in cases where the macroscopical picture raises suspicion of malignancy.AimsDemonstration of the discrimination potential of tissues of different water content using a novel micromachined silicon waveguide probe. Secondarily, the silicon probe miniaturization till an inspection area of 600 x 200 m2, representing a drastic reduction by 96.3% of the probing area, in comparison with a conventional WR-10 waveguide. The high planar resolution is required for histology and early-state skin-cancer detection.Material and methodsTo evaluate the probe three phantoms with different water contents, i.e. 50%, 75% and 95%, mimicking dielectric properties of human skin were characterized in the frequency range of 95-105GHz. The complex permittivity values of the skin are obtained from the variation in frequency and amplitude of the reflection coefficient (S11), measured with a Vector Network Analyzer (VNA), by comparison with finite elements simulations of the measurement set-up, using the commercially available software, HFSS. The expected frequency variation is calculated with HFSS and is based on extrapolated complex permittivities, using one relaxation Debye model from permittivity measurements obtained using the Agilent probe.ResultsMillimeter wave reflection measurements were performed using the probe in the frequency range of 95-105GHz with three phantoms materials and air. Intermediate measurement results are in good agreement with HFSS simulations, based on the extrapolated complex permittivity. The resonance frequency lowers, from the idle situation when it is probing air, respectively by 0.7, 1.2 and 4.26GHz when a phantom material of 50%, 75% and 95% water content is measured.DiscussionThe results of the measurements in our laboratory set-up with three different phantoms indicate that the probe may be able to discriminate between normal and pathological skin tissue, improving the spatial resolution in histology and on skin measurements, due to the highly reduced area of probing.ConclusionThe probe has the potential to discriminate between normal and pathological skin tissue. Further, improved information, compared to the optical histological inspection can be obtained, i.e. the complex permittivity characterization is obtained with a high resolution, due to the highly reduced measurement area of the probe tip.
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| 47. |
- Dancila, Dragos
(author)
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MM-wave integrated RF-MEMS tunable cavity resonators, filters and ultra-low phase-noise oscillators
- 2011
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Doctoral thesis (other academic/artistic)abstract
- Within the Microelectronics Industry, the core research is focused on the realization of the Moore's law, which states that circuit density doubles every 24 months, shaping the framework of the More of Moore paradigm. However, Moore's law is expected to end, as devices are reaching limitations inherent to the approach of the atomical dimensions. Alternative research paths emerged, forming the new More than Moore paradigm. This consists in using the microfabrication technological knowhow towards the realization of alternative devices and applications, among others the miniaturization and integration of Radio Frequency (RF) devices by Micro Electromechanical Systems (MEMS), i.e. RF-MEMS. The RF-MEMS devices offer high performance, tuning by movable parts and open new perspectives at extra high frequency i.e. 30 to 300 GHz. In this thesis, cavity resonators' design and characterization are introduced, as a preliminary discussion. Their integration in the bulk of High Resistivity Silicon (HR-Si) wafers by micromachining techniques is realized at 60 and 75 GHz. Further, the tuning performance induced by internal volumes of perturbation is thoroughly investigated. Furthermore, the integration of a voltage controlled tuning system for air filled cavity resonators is realized at 60 GHz, using a MEMS based Faraday cage. Additionally, a new miniaturization concept is demonstrated using High Impedance Surfaces (HIS). A seven-pole Chebyshev bandpass filter is realized in Low Temperature Co-fired Ceramic (LTCC). Finally, ultra-low phase-noise oscillators at 60 GHz are realized using cavity resonators integrated in HR-Si and LTCC. These oscillators improve the state of the art for integrated oscillators in the frequency band from 40 to 80 GHz, demonstrating the highest factor of merit, to our best knowledge and to date, FoM = -199 dBcHz @ 1MHz offset from the carrier frequency, fosc = 59.98 GHz.
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| 48. |
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| 49. |
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| 50. |
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