| 1. |
- Stake, Jan, 1971, et al.
(författare)
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Terahertz technology and applications
- 2008
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Ingår i: International Symposium on Terahertz between Japan and Sweden.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- THz or submillimetre-wave sensing covers the frequency range from 300 GHz to 10 THz (wavelengths from 1 mm to 30 µm). With energy levels in the 1.2-40 meV range, terahertz interactions with matter involve intermolecular, rather than atomic transitions. This gives rise to some imaging and spectroscopy applications that are unique to this particular region of the electromagnetic spectrum. Many polar molecules in the low pressure gaseous state have strong, narrow band, vibrational and rotational emission or absorption modes that peak in this regime and are used as probes for quantum chemistry, astrophysical processes and the dynamics of planetary atmospheres, including the Earth. Still, the terahertz spectral region is by far the least explored portion of the electromagnetic spectrum. A great obstacle has been the absence of robust and reasonable inexpensive receiver components that can operate at room temperature. The talk will consist of two parts: a) room temperature technology for THz applications and b) terahertz applications in biology and medicine.At Chalmers, several key technologies are explored for future THz systems such as radiometers, radars, spectrometers and communication links for frequencies from approximately 100GHz to several THz. Transistors with 50 nm gate length based on the two dimensional electron gas can at present be used for frequencies up to and above 300 GHz for circuits such as amplifiers, frequency mixers, frequency multipliers, oscillators, and modulators. For even higher frequencies, submicron low noise Schottky diodes are used for heterodyne mixers. We are currently pursuing studies of high functionality THz mixers (SSB) and in-house fabrication of monolithically integrated Schottky diode circuits. Results and progress on single side band mixers at 340 GHz aimed for future climate research satellites such as the ESA PREMIER mission. Furthermore, single chip receivers (MMIC) up to 220 GHz for imaging applications will be presented.THz imaging and spectroscopy for biomedical applications is being targeted for the very first time, including assessment of protein conformational states, molecular binding and interaction, DNA hybridization, isomer identification, skin hydration level, drug delivery, wound healing, tumour identification and margin assessment, and cell processes. The submillimeter wave advanced technology group at Caltech, in conjunction with the group at Chalmers (J.Stake was visiting Caltech under a sabbatical), set up a very flexible exposure and monitoring system to be used to systematically investigate the interaction of THz radiation with cells.The talk will cover the latest results obtained from Chalmers on MMICs and Schottky diode mixers for terahertz frequencies (sensors), as well as results from initial investigations towards thermal and non-thermal effects of THz radiation on biological systems (Caltech/JPL-Chalmers).
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| 2. |
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| 3. |
- Anderberg, Martin, 1992, et al.
(författare)
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A 183-GHz Schottky diode receiver with 4 dB noise figure
- 2019
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Ingår i: IEEE MTT-S International Microwave Symposium Digest. - : IEEE. - 0149-645X. ; 2019-June, s. 172-175
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Konferensbidrag (refereegranskat)abstract
- Atmospheric science based on space-borne millimeter wave measurements require reliable and state-of-the art receivers. In particular, the water vapor line at 183.3 GHz motivates the development of sensitive mixers at this frequency. Traditional assembly techniques employed in the production of Schottky diode receivers involve flip-chip mounting and soldering of discrete dies, which prohibit the implementation of reliable and repeatable production processes. In this work, we present a subharmonic 183 GHz mixer implementing a repeatable assembly method using beamlead Schottky diodes. The mixer was integrated with a InP HEMT MMIC low noise intermediate frequency amplifier resulting in a record-low receiver noise temperature of 450 K at 1 mW of local oscillator power measured at room-temperature. The measured Allan time was 10 s and the third order local oscillator spurious power was less than -60 dBm. The proposed assembly method is of particular importance for space-borne missions but also applicable to a wide range of terahertz applications.
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| 4. |
- Auriacombe, Olivier, 1989, et al.
(författare)
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325 GHz and 650 GHz Dual-polarisation receivers Concept
- 2022
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Ingår i: 32nd International Symposium of Space Terahertz Technology, ISSTT 2022.
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Konferensbidrag (refereegranskat)abstract
- The integrated dual-polarisation receivers utilize a dual probe concept, efficiently integrating the antenna and MMIC package environment which allows for polarisation discrimination without the use of bulky and lossy external orthomode transducers. This concept increases the sensitivity of the instrument and reduces its size, enabling the development of future earth observation arrays. Omnisys Instruments AB (Sweden) and Chalmers University of Technology (Sweden) are working to demonstrate state-of-the-art dual polarisation capability with two integrated receiver modules at 325 GHz and 650 GHz.
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| 5. |
- Drakinskiy, Vladimir, 1977, et al.
(författare)
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Development of planar schottky diodes
- 2011
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Ingår i: 22nd International Symposium on Space Terahertz Technology 2011, ISSTT 2011; Tucson, AZ; United States; 25 April 2011 through 28 April 2011. ; , s. 64-
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Konferensbidrag (refereegranskat)abstract
- We present the development of an air-bridged planar Schottky diode process at Chalmers University of Technology for use in submillimeter wave mixer and multiplier circuits. As a first step evaluation has been targeted for heterodyne receivers (atmosphere sounders) operation at 340 GHz. The aim is to develop a reliable and repeatable discrete Schottky diode process, with good electrical and mechanical characteristics, which also can be scaled to smaller anodes and extended to integrated diode circuits for THz frequencies. Air-bridged Schottky structures were demonstrated in the late 1980's as a reliable, high quality alternative to whisker contacted diodes. This approach gives a mechanically stable structure and still low parasitic capacitances. The Chalmers diode process is based on electron beam lithography, with a beam spot less than 5 nm, which allows for precise anode and airdridge formation. Hence, this process module can also be utilized for submicron size anodes and. terahertz monolithic integrated circuits (TMICs). Several batches with different shapes of anodes have been fabricated and evaluated with respect to DC/RF-performance. Repeatability of the diode's characteristics indicates good control of the diode fabrication process. We will present the main fabrication route, optimization and repeatability of the diodes as well as RF results from mixer and multiplier measurements up to 340 GHz.
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| 6. |
- Drakinskiy, Vladimir, 1977, et al.
(författare)
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Development of planar THz Schottky diodes
- 2011
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Ingår i: 6th ESA Workshop on Millimetre-Wave Technology and Applications.
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Konferensbidrag (refereegranskat)abstract
- We present the technological development of the air bridge planar Schottky diode process at Chalmers University of Technology for the use as submillimeter wave mixer and multiplier. Our first evaluation is targeted for the heterodyne receivers (i.e. atmosphere sounders) operation at 340 GHz. The aim is to develop a reliable and repeatable Schottky diode process, with good electrical and mechanical characteristics. In addition, the scalability of the diode geometry for diode integration in THz circuits is also taken into account in this development.
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| 7. |
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| 8. |
- Drakinskiy, Vladimir, 1977, et al.
(författare)
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Reliability study of THz Schottky mixers and HBV frequency multipliers for space applications
- 2020
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Ingår i: Proceedings of the 31st Symposium on Space Terahertz Technology, ISSTT 2020. ; , s. 118-
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Konferensbidrag (refereegranskat)abstract
- We report status and current results of the preliminary reliability study on 300 GHz InP heterostructure barrier varactor diode multipliers and 1200 GHz GaAs Schottky diode mixers. Both types of diodes are monolithically integrated with circuits and were processed on 3" InP and GaAs wafers respectively using established III-V processing. We will present results on thermal step-stress tests up to 300oC, indicating the operational temperature limitations of the devices. Also, the analysis of the accelerated lifetime testing (1000h) will be discussed.
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| 9. |
- Drakinskiy, Vladimir, 1977, et al.
(författare)
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Status and Progress of Schottky Technology Development for SWI and ISMAR
- 2015
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Ingår i: 26th International Symposium on Space Terahertz Technology, ISSTT 2015; Cambridge; United States; 16 March 2015 through 18 March 2015. ; , s. P-6
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Konferensbidrag (refereegranskat)abstract
- We present the progress of the technological development of a full e-beam based monolithically integrated Schottky diode process applicable for sub-millimetre wave multipliers and mixers. The process has been employed in a number of demonstrators showing state-of-the-art performance.
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| 10. |
- Drakinskiy, Vladimir, 1977, et al.
(författare)
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Terahertz GaAs Schottky diode mixer and multiplier MIC’s based on e-beam technology
- 2013
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Ingår i: Conference Proceedings - International Conference on Indium Phosphide and Related Materials. - 1092-8669. - 9781467361316
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Konferensbidrag (refereegranskat)abstract
- We present the progress of the technological development of a full e-beam based monolithically integrated Schottky diode process applicable for sub-millimetre wave multipliers and mixers. Evaluation of the process has been done in a number of demonstrators showing state-of-the-art performance, including various multiplier circuits up to 200 GHz with a measured flange efficiency of above 35%, as well as heterodyne receiver front-end modules operating at 340 GHz and 557 GHz with a measured receiver DSB noise temperature of below 700 K and 1300 K respectively.
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| 11. |
- Emrich, Anders, 1962, et al.
(författare)
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Water Vapor Radiometer for ALMA
- 2009
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Ingår i: Proc. of 20th International Symposium on Space Terahertz Technology, Charlottesville, USA, 20-22 April, 2009. ; , s. 174-177
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Konferensbidrag (refereegranskat)abstract
- Radiometer for the ALMA project from scratch in 18 months and will deliver 50 units within the next 18 months. Theradiometer includes an Optical Relay, Mounting Frame as well as the Radiometer core module. The radiometer core include optics and calibration system as well as a schottky mixer based frontend and a filterbank back-end. These subsystems are supported by a thermal management subsystem, control and communication subsystem as well as a power subsystem. The system and subsystems will be described in the paper.
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| 12. |
- Emrich, Christina, et al.
(författare)
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Low Power Cryogenic Rad-hard LNAs for Space
- 2019
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Konferensbidrag (refereegranskat)abstract
- We present the design and implementation of a packaged cryogenic InP HEMT MMIC LNA for space borne applications. The particular module is part of the submillimetre wave instrument (SWI) band1 and band2 receiver channel development for the ESA Jupiter ICy moons Explorer mission (JUICE) programme. The main objective of the activity has been to develop a general connectorized rad-hard LNA package for space applications, and to qualify the cryogenic InP HEMT MMIC process at Chalmers University of Tehnology which today covers a frequency range up to the W-band with state-of-the-art performance in terms of noise, gain and power dissipation. The activity has currently moved from a pre-qualification phase to a lot acceptance test (LAT) phase and has up till now included various environmental tests e.g. vibration, total dose radiation tests up to 300kRad on die level, and thermal cycling both to hot and cold temperatures. The InP HEMT MMIC process can be operated at ultra low power with ultra low noise which makes it an excellent candidate for deep space missions and satellite communication links, but also for the next generation of radioastronomy telescopes based on cryogenic receivers e.g. HEB and SIS multipixel cameras.
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| 13. |
- Eriksson, Klas, 1983, et al.
(författare)
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InP DHBT Amplifier Modules Operating Between 150 and 300 GHz Using Membrane Technology
- 2015
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Ingår i: IEEE Transactions on Microwave Theory and Techniques. - 0018-9480 .- 1557-9670. ; 63:2, s. 433-440
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Tidskriftsartikel (refereegranskat)abstract
- In this paper, we present WR05 (140-220 GHz) and WR03 (220-325 GHz) five-stage amplifier modules with novel membrane microstrip-to-waveguide transitions. The modules use a 250-nm InP double heterojunction bipolar transistor (DHBT) technology and multilayer thin-film microstrip transmission lines. The waveguide transitions use E-plane probes on 3- μm-thin GaAs membrane substrate. Beam lead connectors integrated on the transition eliminate the need of highly reactive bond wires. In addition, process steps such as backside metallization, backside vias, and nonrectangular dicing of the integrated circuits (ICs) are not required. The WR05 amplifier module demonstrates a peak gain of 24 dB at 245 GHz and more than 10-dB gain from 155 to 270 GHz. The WR-03 module has 19-dB gain from 230 to 254 GHz with input and output return loss better than 10 dB from 225 to 330 GHz. The two modules were also characterized in terms of noise. The minimum noise figures were measured to 9.7 dB at 195 GHz and 10.8 dB at 240 GHz for the WR05 and WR03 modules, respectively. To the authors' best knowledge, these are the first published results on an InP DHBT amplifier modules operating at these high frequencies. It is also the first time that membrane technology is used for IC packaging, regardless of IC technology.
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| 14. |
- Hammar, Arvid, 1986, et al.
(författare)
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A 600 GHz Orthomode Transducer based on a Waveguide Integrated Wire Grid Polarizer
- 2012
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Ingår i: TWENTY-THIRD INTERNATIONAL SYMPOSIUM ON SPACE TERAHERTZ TECHNOLOGY (ISSTT2012).
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Konferensbidrag (refereegranskat)abstract
- Abstract — We present a new type of orthomode transducer (OMT), involving the integration of a quasi-optical component, namely a wire grid polarizer (WGP), with an E-plane probe transition, in a waveguide topology. The goal has been to create a lightweight and compact device for waveguide integration, capable of covering all frequency channels to be used by the FIRE instrument¤.The design consists of a metallic split block, in which a quadratic waveguide supporting the two fundamental modes of propagation (TE10 and TE01), is formed using regular CNC milling. Just as its quasi-optical counterpart, i.e. a free standing WGP, a waveguide integrated WGP insert is used to separate the two orthogonal TE modes, which are either reflected or transmitted (depending on polarization). A planar E-plane waveguide probe transition realized on a GaAs membrane is used inside a square waveguide to extract the reflected mode without affecting the transmitted mode. For a first proof of concept the OMT has been designed for the possibility of full characterization and therefore the transmitted mode is guided through a stepped impedance transformer to a standard rectangular waveguide interface, while a second E-plane probe transition to a rectangular waveguide, is used for the reflected mode. Simulations carried out using Ansoft HFSS show that the OMT design can be made relatively broadband (currently about ~14% with a return loss better than 15 dBs) and with cross-polarizations better than 30 dB. The probe and WGP can be manufactured using high precision photolithography or E-beam lithography making it scalable to both lower and higher frequency bands. Assembling an OMT of this type involves mounting of small membrane structures (
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| 15. |
- Hammar, Arvid, 1986, et al.
(författare)
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Low noise 874 GHz receivers for the international submillimetre airborne radiometer (ISMAR)
- 2018
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Ingår i: Review of Scientific Instruments. - : AIP Publishing. - 1089-7623 .- 0034-6748. ; 89:5
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Tidskriftsartikel (refereegranskat)abstract
- We report on the development of two 874 GHz receiver channels with orthogonal polarizations for the international submillimetre airborne radiometer. A spline horn antenna and dielectric lens, a Schottky diode mixer circuit, and an intermediate frequency (IF) low noise amplifier circuit were integrated in the same metallic split block housing. This resulted in a receiver mean double sideband (DSB) noise temperature of 3300 K (minimum 2770 K, maximum 3400 K), achieved at an operation temperature of 40 C and across a 10 GHz wide IF band. A minimum DSB noise temperature of 2260 K at 20 C was measured without the lens. Three different dielectric lens materials were tested and compared with respect to the radiation pattern and noise temperature. All three lenses were compliant in terms of radiation pattern, but one of the materials leads to a reduction in a noise temperature of approximately 200 K compared to the others. The loss in this lens was estimated to be 0.42 dB. The local oscillator chains have a power consumption of 24W and consist of custom-designed Schottky diode quadruplers (5% power efficiency in operation, 8%-9% peak), commercial heterostructure barrier varactor (HBV) triplers, and power amplifiers that are pumped by using a common dielectric resonator oscillator at 36.43 GHz. Measurements of the radiation pattern showed a symmetric main beam lobe with full width half maximum <5 and side lobe levels below 20 dB. The return loss of a prototype of the spline horn and lens was measured using a network analyzer and frequency extenders to be 750-1100 GHz. Time-domain analysis of the reflection coefficients shows that the reflections are below 25 dB and are dominated by the external waveguide interface.
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| 16. |
- Hammar, Arvid, 1986, et al.
(författare)
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THz smooth-walled spline horn antennas: Design, manufacturing and measurements
- 2016
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Ingår i: 2016 IEEE Antennas and Propagation Society International Symposium, APSURSI 2016, Fajardo, Puerto Rico, 26 June - 1 July 2016. - 1947-1491. - 9781509028863 ; , s. 1341-1342
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Konferensbidrag (refereegranskat)abstract
- We describe a versatile and cost-efficient method for producing smooth-walled spline horn antennas for applications in THz radiometry. Specifically, the development of four different horns for radiometer receiver applications at frequencies 120, 183, 340 and 874 GHz is presented. General methods for efficient optimization of the spline profiles have been developed which enable the horn designs to be tailored to each application. All four designs display high Gaussicity (typically ∼98%). Manufacturing methods based on numerical milling in splitblocks, lathing and drilling have been tested and compared. Milled splitblock horns with integrated receiver circuits (Shottky mixers in this case) allow for lower losses in the receiver system at the expense of higher cross-polarization levels. The radiation pattern of three designs at 183, 340 and 874 GHz have been measured using planar and rotational scanners.
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| 17. |
- Hanning, Johanna, 1981, et al.
(författare)
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A Broadband THz Waveguide-to-suspended Stripline Loop-probe Transition
- 2017
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Ingår i: IEEE MTT-S International Microwave Symposium Digest. - 0149-645X. - 9781509063604 ; , s. 1091-1094
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Konferensbidrag (refereegranskat)abstract
- We present a novel waveguide-to-suspended stripline loop-probe transition operating over the entire WR-1.0 waveguide band. The loop probe is designed for broadband response with simulated RL > 15 dB, and has an integrated DC return path, which can also be extended for biasing. The measured insertion loss for a back-to-back configuration is 1 – 2 dB in almost the entire frequency range of 750 – 1100 GHz.
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| 18. |
- Hanning, Johanna, 1981, et al.
(författare)
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Single Flange 2-port Design For THz Integrated Circuit S-parameter Characterization
- 2013
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Ingår i: International Conference on Infrared, Millimeter, and Terahertz Waves, IRMMW-THz. - 2162-2027 .- 2162-2035. ; , s. 1-2
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Konferensbidrag (refereegranskat)abstract
- A single flange 2-port TRL calibration and measurement setup for accurate THz S-parameter characterization of integrated membrane circuit devices is proposed. The proposed setup facilitates shorter access waveguides, which greatly improves the calibration uncertainty.
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| 19. |
- Hanning, Johanna, 1981, et al.
(författare)
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Single-Flange 2-Port TRL Calibration for Accurate THz S-Parameter Measurements of Waveguide Integrated Circuits
- 2014
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Ingår i: IEEE Transactions on Terahertz Science and Technology. - 2156-342X .- 2156-3446. ; 4:5, s. 582-587
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Tidskriftsartikel (refereegranskat)abstract
- This paper describes a single flange 2-port measurement setup for S-parameter characterization of waveguide integrated devices. The setup greatly reduces calibration and measurement uncertainty by eliminating vector network analyzer (VNA) extender cable movement and minimizing the effect of waveguide manufacturing tolerances. Change time of standards is also improved, reducing the influence of VNA drift on the uncertainty. A TRL calibration kit has been manufactured and measurements are demonstrated in WR-03 (220–325 GHz).
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| 20. |
- Jacob, Karl, et al.
(författare)
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Characterization of the 530-625 GHz receiver unit for the Jupiter mission JUICE/SWI
- 2015
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Ingår i: Proceedings of the 36th ESA Antenna Workshop on Antennas and RF Systems for Space Science.
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Konferensbidrag (refereegranskat)abstract
- The Submillimetre Wave Instrument (SWI) is being developed for the Jupiter Icy moons Explorer (JUICE) missionof the European Space Agency (ESA). In this paper we give an overview of the 530 GHz to 625 GHz receiver unit of SWI and present the first noise temperature measurements covering the complete receiver bandwidth at room temperature operation. In this context we will point out the difficulties with the highly variable local oscillator power within the bandwith, which needs a careful tuning of the multiplier bias voltages in order to optimize the noise temperature and to avoid damage of the mixers. In addition we show initial results at cold temperature operation. Furthermore we will present a first stability measurement showing the temperature dependence of the receiver gain at room temperature operation.
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| 21. |
- Jacob, Karl, et al.
(författare)
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Radiometric performance of the 530 to 625 GHz receiver unit of the submillimetre wave instrument on juice
- 2019
-
Ingår i: ISSTT 2019 - 30th International Symposium on Space Terahertz Technology, Proceedings Book. ; , s. 28-31
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Konferensbidrag (refereegranskat)abstract
- The upcoming Submillimeter Wave Instrument on the JUICE spacecraft is a passive radiometer/spectrometer instrument with two heterodyne receivers which are independently tunable in the frequency bands 530 to 625 GHz and 1080 to 1275 GHz. It will study Jupiter’s atmosphere as well as the atmospheres and surface properties of the Galilean moons. This work presents the results of first radiometric tests with a prototype of the 600 GHz receiver. In this context, the baseline ripples caused by the internal calibration target have been characterized using two conical prototypes with a linear and an exponential absorber coating profile. A significant reduction of the baseline ripple amplitude has been measured with the target having the exponential cone profile. The spectroscopic baseline has been characterized for various frequency steps when applying frequency switching as an alternative calibration mode. At some operating frequencies a very flat switching baseline has been measured for frequency throws up to 90 MHz, while at other frequencies significant spectral distortions are measured even with a step size of 22.5 MHz. The first radiometric tests of the sideband gain ratio with a passive Fourier Transform Spectroscopy method demonstrate the general applicability in the 530 to 625 GHz band.
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| 22. |
- Jayasankar, Divya, et al.
(författare)
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A 3.5-THz, ×6-Harmonic, Single-Ended Schottky Diode Mixer for Frequency Stabilization of Quantum-Cascade Lasers
- 2021
-
Ingår i: IEEE Transactions on Terahertz Science and Technology. - : IEEE Microwave Theory and Techniques Society. - 2156-342X .- 2156-3446. ; 11:6, s. 684-694
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Tidskriftsartikel (refereegranskat)abstract
- Efficient and compact frequency converters are essential for frequency stabilization of terahertz sources. In this article, we present a 3.5-THz, × 6-harmonic, integrated Schottky diode mixer operating at room temperature. The designed frequency converter is based on a single-ended, planar Schottky diode with a submicron anode contact area defined on a suspended 2-μ m ultra-thin gallium arsenide substrate. The dc-grounded anode pad was combined with the radio frequency E-plane probe, which resulted in an electrically compact circuit. At 200-MHz intermediate frequency, a mixer conversion loss of about 59 dB is measured resulting in a 40-dB signal-to-noise ratio for phase locking a 3.5-THz quantum-cascade laser. Using a quasi-static diode model combined with electromagnetic simulations, good agreement with the measured results was obtained. Harmonic frequency converters without the need of cryogenic cooling will help in the realization of highly sensitive space and air-borne heterodyne receivers.
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| 23. |
- Jayasankar, Divya, 1994, et al.
(författare)
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A 4.7-THz fundamental Schottky diode mixer
- 2022
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Ingår i: International Conference on Infrared, Millimeter, and Terahertz Waves, IRMMW-THz. - 2162-2027 .- 2162-2035. ; 2022-August
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Konferensbidrag (refereegranskat)abstract
- Fundamental mixers operating at ambient temperatures are essential for realising long-lifetime space missions aiming to measure gas spectra at terahertz frequencies. This paper presents the design and sensitivity analysis of a 4.7-THz fundamental mixer. At supra-THz frequencies, fabrication and assembly tolerances substantially affect the mixer performance, and it is essential to identify critical circuit parameters. This work presents the progress towards a room-temperature heterodyne supra-terahertz receiver.
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| 24. |
- Jayasankar, Divya, 1994, et al.
(författare)
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Design and Characterisation of a 3.5-THz Fundamental Schottky Mixer
- 2022
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Ingår i: 32nd International Symposium of Space Terahertz Technology, ISSTT 2022.
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Konferensbidrag (refereegranskat)abstract
- Mixers operating at ambient temperatures are essential for realisation of THz heterodyne receivers for long lifetime space missions. In this paper, we report the design, circuit and block fabrication, assembly and characterisation of a 3.5-THz fundamental Schottky diode mixer. Design of planar, integrated mixer circuit realised using a suspended stripline technology on a 2-µm GaAs substrate and video signal detection results are presented.
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| 25. |
- Jayasankar, Divya, et al.
(författare)
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Design and development of 3.5 THz Schottky-based fundamental mixer
- 2021
-
Ingår i: 2020 50th European Microwave Conference, EuMC 2020. - : Institute of Electrical and Electronics Engineers Inc.. - 9782874870590 ; , s. 595-598
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Konferensbidrag (refereegranskat)abstract
- Broadband Schottky diode mixers operating at room-temperature are crucial for terahertz heterodyne instrumentation in space-borne applications. In this paper, we present the design of a compact 3.5 THz fundamental single-ended Schottky diode mixer. The design is based on Schottky diodes with a sub-micron anode area, defined using nanolithography techniques, and integrated with suspended strip lines on an ultra-thin GaAs-membrane.
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| 26. |
- Jayasankar, Divya, 1994, et al.
(författare)
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Development of Supra-THz Schottky Diode Harmonic Mixers
- 2021
-
Ingår i: International Conference on Infrared, Millimeter, and Terahertz Waves, IRMMW-THz. - 2162-2027 .- 2162-2035. - 9781728194240 ; 2021-August
-
Konferensbidrag (refereegranskat)abstract
- In this paper, we report the development of single-ended, Schottky diode-based harmonic mixers operating at 3.5 THz and 4.7 THz, respectively. Both mixers utilize a sub-micron size Schottky diode fabricated with circuit elements on a suspended 2 um-thick GaAs stripline circuit and then assembled in a waveguide split-block. The diode is closely integrated with the RF-waveguide, resulting in an electrically small and compact circuit. For the 3.5-THz, x6-harmonic mixer, a conversion loss of about 60 dB was measured at an intermediate frequency (IF) of 200 MHz. The predicted mixer performance versus dc bias agrees well with the measurements. Based on these results, the preliminary design and simulation results of a 4.7-THz, x8-harmonic mixer, are presented.
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| 27. |
- Jayasankar, Divya, 1994, et al.
(författare)
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Effect of idler terminations on the conversion loss for THz Schottky diode harmonic mixers
- 2019
-
Ingår i: International Conference on Infrared, Millimeter, and Terahertz Waves, IRMMW-THz. - 2162-2027 .- 2162-2035. ; 2019-September
-
Konferensbidrag (refereegranskat)abstract
- Efficient and reliable frequency converters, preferably operating at room temperature, are critical components for frequency-stabilizing terahertz sources. In this work, we present the analysis of optimum configurations for Schottky diode-based x4, x6, and x8 harmonic mixers operating at 2.3 THz, 3.5 THz, and 4.7 THz respectively. Detailed large-signal analysis of the two basic single-ended Z- and Y-mixers was carried out using a standard Schottky-diode model. For each case, the conversion loss was minimized by finding optimal embedding impedances at RF, LO, and IF frequencies. The analysis shows that the Y-mixer has less conversion loss at a low LO pump power. However, the Z-mixer provides reduced loss with increasing harmonic index and pump power due to the associated power dissipation in idler circuits. The results provide preliminary design guidelines for room- temperature frequency converters and their use in phase-locked loop applications.
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| 28. |
- Karandikar, Yogesh, 1982, et al.
(författare)
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A 874 GHz Mixer Block Integrated Spline Horn and Lens Antenna for the ISMAR Instrument
- 2015
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Ingår i: 9th European Conference on Antennas and Propagation, EuCAP 2015, Lisbon, Portugal, 13-17 May 2015. - 9788890701856
-
Konferensbidrag (refereegranskat)abstract
- In this paper, we present the design of a 874 GHz mixer block-integrated antenna for the ISMAR Instrument. The spline horn antenna with a dielectric lens (Teflon) is used to fulfill the requirement of an on-axis Directivity exceeding 32 dBi. The well designed spline horn offers very high Gaussian Coupling, exceeding 97%. This property of spline horn further helps to achieve very rotationally symmetric beam even after the lens with very low cross-polarization (
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| 29. |
- Malko, Aleksandra, 1984, et al.
(författare)
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Heterogeneous Integration of Terahertz Diode Circuits
- 2016
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Ingår i: 2015 Asia-Pacific Microwave Conference. ; 1
-
Konferensbidrag (refereegranskat)abstract
- We present an overview of the research made on integrated diode circuits for terahertz applications. This includes progress on heterogeneous integration of heterostructure barrier varactor multipliers and Schottky diode mixers on silicon substrate. The described technology uses silicon-on-insulator (SOI) substrates, for which accurate and well defined substrate thickness for the microstrip circuitry is obtained.
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| 30. |
- Neumaier, Philipp, 1984, et al.
(författare)
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Molecular Spectroscopy With a Compact 557-GHz Heterodyne Receiver
- 2014
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Ingår i: IEEE Transactions on Terahertz Science and Technology. - 2156-342X .- 2156-3446. ; 4:4, s. 469-478
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Tidskriftsartikel (refereegranskat)abstract
- We report on a heterodyne terahertz spectrometer based on a fully integrated 557-GHz receiver and a digital fast Fourier transform spectrometer. The receiver consists of a chain of multipliers and power amplifiers, followed by a heterostructure barrier varactor tripler that subharmonically pumps a membrane GaAs Schottky diode mixer. All sub-components are newly developed and optimized with regard to the overall receiver performance such as noise temperature, power consumption, weight and physical size. The receiver works at room temperature, has a double sideband noise temperature as low as 2000 K at a maximum power consumption of 4.5 W with an Allan time of 10 s and a sideband gain ratio of 0.52. The performance of the spectrometer is demonstrated by absorption spectroscopy of H2O and CH3OH with an instantaneous bandwidth of 1.5 GHz and a resolution of 183 kHz. Several pressure broadening parameters of methanol absorption lines were determined, that agree with other published data. Using the experimentally determined molecular parameters the CH3OH absorption spectrum could be modeled with very high precision.
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| 31. |
- Neumaier, Philipp, 1984, et al.
(författare)
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Molecular spectroscopy with a compact 557 GHz heterodyne receiver
- 2013
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Ingår i: International Conference on Infrared, Millimeter, and Terahertz Waves, IRMMW-THz. - 2162-2027 .- 2162-2035.
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Konferensbidrag (refereegranskat)abstract
- In this work the results of spectroscopic and performance measurements with a compact heterodyne receiver in the frequency range between 520 and 590 GHz are presented.
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| 32. |
- Olsen, Arne, 1974, et al.
(författare)
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HBV Frequency Quintuplers
- 2005
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Ingår i: 16th International Symposium on Space Terahertz Technology.
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Konferensbidrag (refereegranskat)abstract
- A 500 GHz heterostructure-barrier-varactor quintupler has been designed and fabricated. The design consists of a mixture of waveguide and microstrip components for impedance matching. A InP based HBV diode is flip-chip mounted onto the quartz circuit, where beam-leads are used for ground connections to the waveguide block. Extensive back-side processing has been carried out in order to create these beam-leads. The multiplier is a frequency scaled version of a successful 100 GHz quintupler with a conversion efficiency of 11.4%.
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| 33. |
- Richter, Heiko, et al.
(författare)
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Frequency stabilization of 3.5-THz and 4.7-THz quantum-cascade lasers by a phase-locked loop
- 2022
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Ingår i: 32nd International Symposium of Space Terahertz Technology, ISSTT 2022.
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Konferensbidrag (refereegranskat)abstract
- We report on a phase-locked loop for quantum-cascade lasers operating at 3.5 and 4.7 THz. These frequencies are particularly relevant in atmospheric science and astronomy. The QCLs are locked to the multiplied output of a frequency synthesizer using a Schottky diode harmonic mixer. The resulting linewidths are in the order of a few Hz.
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| 34. |
- Richter, Heiko, et al.
(författare)
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Phase Locking of 3.5-THz and 4.7-THz Quantum-Cascade Lasers Using a Schottky Diode Harmonic Mixer
- 2021
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Ingår i: International Conference on Infrared, Millimeter, and Terahertz Waves, IRMMW-THz. - 2162-2027 .- 2162-2035. ; 46
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Konferensbidrag (refereegranskat)abstract
- High frequency accuracy and stability are important requirements for local oscillators in terahertz heterodyne spectrometers. We report on a phase-locked loop for quantum-cascade lasers (QCLs) operating at 3.5 and 4.7 THz, two very important frequencies in atmospheric science and astronomy. The QCLs are locked to the multiplied output of a frequency synthesizer using a Schottky diode harmonic mixer.
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| 35. |
- Richter, Heiko, et al.
(författare)
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Phase-Locking of Quantum-Cascade Lasers Operating Around 3.5 THz and 4.7 THz with a Schottky-Diode Harmonic Mixer
- 2024
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Ingår i: IEEE Transactions on Terahertz Science and Technology. - 2156-342X .- 2156-3446. ; 14:3, s. 346-353
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Tidskriftsartikel (refereegranskat)abstract
- Quantum-cascade lasers (QCLs) are critical components for high-resolution terahertz spectroscopy, especially in heterodyne spectrometers, where they serve as local oscillators. For this purpose, QCLs with stable frequencies and narrow linewidths are essential since their spectral properties limit the spectral resolution. We demonstrate the phase-locking of QCLs around 3.5 THz and 4.7 THz in mechanical cryocoolers. These frequencies are particularly interesting for atmospheric research because they correspond to the hydroxyl radical and the neutral oxygen atom. The phase-locked loop is based on frequency mixing of the QCLs at 3.5 and 4.7 THz with the sixth and eighth harmonic, respectively, generated by an amplifier-multiplier chain operating around 600 GHz, with a Schottky diode harmonic mixer. At both frequencies we achieved a linewidth of the intermediate frequency signal of less than 1 Hz. This is about seven orders of magnitude less than the linewidth of the free running QCL.
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| 36. |
- Sobis, Peter, 1978, et al.
(författare)
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300 GHz to 1.2 THz GaAs Schottky membrane TMIC’s for next generation space missions
- 2013
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Ingår i: 24th International Symposium on Space Terahertz Technology.
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Konferensbidrag (refereegranskat)abstract
- For future earth observation and planetary exploration missions (e.g. STEAMR, MetOp, GEOSOUNDER, SWI, FIRE, GEOSTAR), high performance room-temperature heterodyne receivers in the 50 GHz to 1.5 THz frequency range are needed. For frequencies up to 300 GHz, GaAs and InP HEMT technology has today become competitive, offering high sensitivity along with all the benefits of traditional MMIC designs, e.g. multifunctional chips and high repeatability. For frequencies let say above 300 GHz, GaAs Schottky diode technology can offer an unprecedented noise performance along with the versatility of working both as a source and detector. The long track record and high reliability of Schottky diode receiver technology makes it the natural choice for high-performance room-temperature space instrumentation operating in the THz range.To fully benefit from the performance that Schottky diode technology can offer, monolithically integrated circuit (MIC) membrane technology [1-3] is necessary. By monolithic integration of THz Schottky diodes on ultrathin substrates and using freestanding metal beam leads, low loss transmission line structures suitable for waveguide integration assembly (waveguide probes, DC and RF interconnects etc.) become possible. Terahertz Membrane Integrated Circuits (TMIC’s) have proven to operate well up to several THz overcoming many of the problems and limitations associated with hybrid technology (using discrete flip chip mounted diodes). Thereto the superior repeatability of TMIC technology opens up for the possibility of multichip integrated assemblies and system on chip solutions, which in turn can enable completely new instrument concepts. We will present on the progress of our GaAs Schottky technology based radiometer systems and the development of monolithically integrated multipliers and mixers based on the Chalmers diode membrane process. Specifically we will present ongoing work from the STEAMR instrument development operating at 340 GHz, as well as on the development of 664/1200 GHz receiver prototypes relevant to upcoming space missions.
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| 37. |
- Sobis, Peter, 1978, et al.
(författare)
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4.7 THz GaAs Schottky diode receiver components
- 2019
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Ingår i: ISSTT 2019 - 30th International Symposium on Space Terahertz Technology, Proceedings Book. ; , s. 133-
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Konferensbidrag (refereegranskat)
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| 38. |
- Sobis, Peter, 1978, et al.
(författare)
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A 110 GHz GaAs Schottky Diode Mixer on Quartz with planar LO feed
- 2005
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Ingår i: Gigahertz, Uppsala Sweden, November 8-9 2005.
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Konferensbidrag (refereegranskat)abstract
- A fixed-tuned 110 GHz subharmonically pumped GaAs schottky diodemixer design with planar LO feeding is presented. The designconsists of a shielded microstrip circuit on a 5 mil thick quartzsubstrate, mounted in a full height WR-08 RF waveguide split blockdesign. The UMS DBES105a diode series pair is used as a non-linearmixing element and substrate vias are used for the IF/DC groundreturn. The planar microstrip circuitry, waveguide interface anddiode chip have been modeled and simulated in HFSS. Simulatedresults are showing a conversion loss of 10 dB, with less than 7dBm LO power, with RF and LO bandwidths of more than 10%.Simulations will be verified with experimental results.
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| 39. |
- Sobis, Peter, 1978, et al.
(författare)
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A 170 GHz 45 degree Hybrid for Submillimeter Wave Sideband Separating Subharmonic Mixers
- 2008
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Ingår i: IEEE Microwave and Wireless Components Letters. - 1558-1764 .- 1531-1309. ; 18:10, s. 680-682
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Tidskriftsartikel (refereegranskat)abstract
- We present a 135/45 degree phase shifter hybrid intended to be used in subharmonic sideband separation mixer schemes at submillimeter-wave frequencies. The design consists of an increased height 90 degree 6-arm branch guide coupler with a three stub loaded differential line 45 degree phase shifter at the output. The device has been implemented at G-band in an E-plane WR-05 splitblock design with a center frequency of 170 GHz and 15% bandwidth. Measured S-parameter are in good agreement with simulations showing an isolation and return loss better than 20 dB and an amplitude and phase imbalance within 0.4 dB and 2 degree, respectively.
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| 40. |
- Sobis, Peter, 1978, et al.
(författare)
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A 340 GHz 2SB Schottky Receiver for the STEAMR Limb Sounder
- 2010
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Ingår i: The 35th International Conference on Infrared, Millimeter and THz Waves. - 9781424466573
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Konferensbidrag (refereegranskat)abstract
- A low VSWR sideband separating receiver topology employing subharmonic Schottky diode mixers has been implemented at 340 GHz as an integrated module housing mixers, commercial LNA's and waveguide hybrids. Image rejection levels of around 20 dB and a receiver SSB noise of 9000 K are measured.
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| 41. |
- Sobis, Peter, 1978, et al.
(författare)
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A Broadband, Low Noise, Integrated 340 GHz Schottky Diode Receiver
- 2012
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Ingår i: IEEE Microwave and Wireless Components Letters. - 1558-1764 .- 1531-1309. ; 22:7, s. 366-368
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Tidskriftsartikel (refereegranskat)abstract
- A 340 GHz subharmonic Schottky diode mixer and a multioctave (3–16 GHz) custom low noise amplifier (LNA) have been integrated to form a compact receiver front-end module, exhibiting ultra low noise with an exceptional flat response and broadband instantaneous frequency coverage. At room temperature, a receiver noise temperature of 870 K is measured at an LO drive of 1.2 mW at 170 GHz. The total dc power consumption of the LNA is below 120 mW. Measurements are in good agreement with simulations taking the mixer and LNA mismatch interaction into account.
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| 42. |
- Sobis, Peter, 1978, et al.
(författare)
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A Low VSWR 2SB Schottky Receiver
- 2011
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Ingår i: IEEE Transactions on Terahertz Science and Technology. - 2156-342X .- 2156-3446. ; 1:2, s. 403-411
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Tidskriftsartikel (refereegranskat)abstract
- A novel high performance waveguide integrated sideband separating (2SB) Schottky receiver operating in the 320 -360 GHz band is presented. The unique receiver design is based on a core of two subharmonic Schottky diode mixers with embedded LNA’s with a minimum noise figure of 1.8 dB, fed by LO and RF quadrature hybrids. At room temperature, a typical receiver SSB noise temperature of 3000 K is measured over most of the band reaching a minimum of 2700 K, with only 4 mW of LO power. The sideband ratio SBR is typically below 15 dB over the whole band and the measured LO input return loss is typically below 15 dB broadband. High performance sideband separating Schottky receivers can now for the first time be considered for submillimeter wave systems enabling new types of instrument concepts.
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| 43. |
- Sobis, Peter, 1978, et al.
(författare)
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A Low VSWR 340 GHz 2SB Schottky Receiver for Earth Observation Applications
- 2011
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Ingår i: 22nd International Symposium on Space Terahertz Technology 2011, ISSTT 2011. ; , s. 201-202
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Konferensbidrag (refereegranskat)abstract
- A waveguide integrated 2SB Schottky receiver operating in the 320-360 GHz band with a performance similar to state-of-the-art DSB Schottky mixers is demonstrated. The unique receiver topology utilizes a low RF and LO VSWR design leading to better mixer performance and superior response for the radiometer system in general. On average a 15 dB SBR is measured over the RF band and a LO return loss of 15 dB broadband.
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| 44. |
- Sobis, Peter, 1978, et al.
(författare)
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A Low VSWR 340 GHz 2SB Schottky Receiver for Earth Observation Applications
- 2011
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Ingår i: 6th ESA Workshop on Millimetre-Wave Technology and Applications and 4th Global Symposium on Millimeter Waves; 23rd 25th May, Espooo, Finland.
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Konferensbidrag (refereegranskat)abstract
- A state-of-the-art waveguide integrated 2SB Schottky receiver operating in the 320-360 GHz band is demonstrated. The unique receiver topology utilizes a low RF and LO VSWR design leading to better mixer performance and superior response for the radiometer system in general. Characterization of the receiver system will be presented.
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| 45. |
- Sobis, Peter, 1978
(författare)
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Advanced Schottky Diode Receiver Front-Ends for Terahertz Applications
- 2011
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis treats the development of high frequency circuits for increased functionality of terahertz receiver front-ends based on room temperature Schottky diode technology. This includes the study of novel circuit integration schemes, packaging concepts as well as new measurement and characterisation techniques.As the main result, a novel broadband waveguide integrated sideband separating (2SB) receiver topology for future Earth observation submillimetre wave instruments is proposed. The 2SB receiver topology has an inherent low RF and LO port voltage standing wave ratio (VSWR) and high sideband ratio (SBR). It is based on subharmonic (x2) Schottky diode double sideband (DSB) mixers with embedded IF low noise amplifiers (LNA's) and LO and RF 90 degree waveguide hybrids. Access to the IF IQ-paths makes it possible to implement phase and amplitude imbalance compensation schemes. Sideband separation is done in the analog domain by the use of an IF 90 degree hybrid or in the digital domain by using an IQ-correlator spectrometer. The use of embedded LNA's reduces the IF losses and leads to a low ripple and broadband response.Measured results on a prototype 2SB receiver operating in the 320 GHz to 360 GHz frequency range show an untuned SBR of 15 dB over the whole band and mixer noise consistent with the optimal performance of a DSB mixer. The LO return loss is measured to be approximately 15 dB (broadband) and the RF return loss is estimated to have similar performance. A 340 GHz DSB receiver with an embedded custom designed 3-15 GHz LNA has also been developed. By co-simulation of the mixer and LNA using a simple mixer noise model it is shown that accurate prediction of the receiver noise response is possible. The DSB receiver exhibits ultra low noise over the 12 GHz IF bandwidth, with a minimum input receiver noise temperature of 870 K (DSB).Two novel differential line phase shifters based on stepped impedance and coupled-line filter structures are proposed. The filters have a minimum lateral distribution making them well suited for use in submillimetre wave circuits. A method for TRL-calibration of terahertz monolithic integrated circuits (TMIC's) is also proposed and demonstrated. The method allows for embedded S-parameter characterisation of waveguide integrated TMIC devices and circuits.
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| 46. |
- Sobis, Peter, 1978, et al.
(författare)
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Compact 340 GHz Receiver Front-Ends
- 2009
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Ingår i: 20th International Symposium on Space Terahertz Technology. ; , s. 183-189
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Konferensbidrag (refereegranskat)abstract
- A compact 340 GHz room temperature receiver front-end has been developed consisting of a subharmonic Schottky diode mixer module with an integrated LNA. A novel sideband separation topology has been evaluated by using a pair of the developed mixers interconnected by external waveguide branch guide coupler hybrids for the LO and RF feedings and coaxial IF hybrids, measuring sideband suppression levels of 5 dB to 15 dB over the 315-365 GHz band.For efficient LO pumping of the sideband separating mixer, a novel high power LO chain based on a 5 x 34 GHz HBV quintupler (170 GHz LO source) has been developed with an ultra compact mechanical block housing, not much larger then a waveguide flange. We have also looked into a broadband medium LO power source consisting of a W-band active multiplier module, based on commercial MMIC chips from Hittite, followed by a medium power Schottky doubler from VDI.The demonstrated compact receiver front end has a considerably reduced size and weight owing to the high multiplication factor of the compact LO chain and mixer with integrated LNA. The novel sideband separating topology that uses 90 degree hybrids for both LO and RF resolves the standing wave issue of a previously proposed topology, in which a matched Y-junction was used as an RF hybrid and a branch guide coupler with a 45 degree differential line phase shifter at the output, was used for the LO feeding. The proposed topology improves both the sideband suppression and reduces the standing waves at the LO and RF ports.
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| 47. |
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| 48. |
- Sobis, Peter, 1978, et al.
(författare)
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Design of a Subharmonic 340 GHz GaAs Schottky Diode Mixer on Qaurtz with Integrated Planar LO-IF Duplexer
- 2006
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Ingår i: 4th ESA Workshop on Millimetre Wave Technology and Applications.
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Konferensbidrag (refereegranskat)abstract
- A fixed tuned 340 GHz sub-harmonically pumped GaAs schottky diode mixer design is presented. The design consists of a 50 µm thick quartz microstrip circuit mounted in a full height waveguide splitblock and uses a flip-chip mounted VDI SC1T2-D20 anti-parallel diode pair. The RF and LO waveguide to microstrip transitions are located at each end of the substrate and a planar LO-IF duplex filter has been integrated with the mixer circuitry, providing for the possibility of planar LO feeding in the future. A comparison of the coaxial with the lumped port method for EM modeling of the diode is presented, showing good agreement between the two methods. The diode parameters and IV characteristics have been matched with a standard diode model used in the harmonic balance analysis of the complete mixer circuit. Preliminary test results from a conceptually scaled 110 GHz mixer design using the UMS DBES105a schottky diode chip are presented showing a conversion loss of 10.8 dB with 3 dBm of LO power.
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| 49. |
- Sobis, Peter, 1978, et al.
(författare)
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Development of a Compact 340 GHz Receiver Front-End
- 2009
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Ingår i: 5th ESA Workshop on Millimetre Wave Technology and Applications. ; :WPP-300, s. 123-130
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Konferensbidrag (refereegranskat)abstract
- A compact 340 GHz roomtemperature receiver front-end module has been developed consisting of a subharmonic Schottky diode mixer module with an integrated LNA. A novel sideband separation topology has been evaluated by using a pair of the developed mixers interconnected by external waveguide branch guide coupler hybrids for the LO and RF feedings and coaxial IF hybrids, measuring sideband suppression levels of 5dB to 15dB over the 315-365 GHz band.For efficient LO pumping of the image rejection mixer, a novel high power LO chain based on a 5 x 34 GHz HBV quintupler (170 GHz LO source) has been developed with an ultra compact mechanical block housing, not much larger then a waveguide flange. The HBV LO source has been compared to a broadband medium power source consisting of a W-band active multiplier module, based on commercial MMIC chips from Hittite, followed by a medium power Schottky doubler from VDI.The demonstrated compact receiver front-end has considerably reduced size and weight owing to the high multiplication factor of the compact LO chain and mixer integrated LNA. The novel image rejection topology resolves the standing wave issue of a previously proposed topology, improving both the image rejection response and reducing the standing waves at the LO and RF ports.
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| 50. |
- Sobis, Peter, 1978, et al.
(författare)
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Discrete GaAs Schottky beamlead mixer diodes for space-borne receiver applications
- 2019
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- This paper presents the design and implementation of a anti-parallell GaAs Schottky beamlead mixer diode suitable for use in discrete diode type subharmonic mixer applications up to about 500 GHz. The particular chip has been developed for the MWI instrument 118 GHz receiver channel which is part of the METOP Second Generation weather and climate research satellite programme. The main objective of the activity has been to develop a fabrication route for “pick and place” type antiparallel diode chip structures employing beamlead interconnects as a part of an ESA supervised lot acceptance testing (LAT) program. This has included qualification of the Chalmers E-beam based GaAs Schottky diode membrane process and statistical on-wafer yield analysis, assembly methods for beamlead type diodes, and pre-qualification activities. The results so far include 96 hours of biased and 500 hours of unbiased high humidity high temperature tests conducted at 85 degrees C and 85 % relative humidity, high temperature tests, total dose tests of up to 2 MRad and bondpull strength tests on representative carriers. The MetOp 118 GHz receiver development is currently in a pre-LAT phase with final LAT program scheduled to the end of 2018.
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