| 1. |
- Belitsky, Victor, 1955, et al.
(författare)
-
Facility Heterodyne Receiver for the Atacama Pathfinder Experiment Telescope
- 2007
-
Ingår i: Proceedings of Joint 32nd International Conference on Infrared Millimeter Waves and 15th International conference on Terahertz Electronics, Sept 3-7, 2007, City Hall, Cardiff, Wales, UK. ; , s. 326-328
-
Konferensbidrag (refereegranskat)
|
|
| 2. |
- Belitsky, Victor, 1955, et al.
(författare)
-
Heterodyne Single-Pixel Facility Instrumentation for APEX Telescope
- 2006
-
Ingår i: in "Millimeter and Submillimeter Detectors for Astronomy III", eds. J. Zmuidzinas, W.S. Holland, S. Withington, W.D. Duncan, Proceedings of SPIE. ; 6275, s. 15-
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)
|
|
| 3. |
- Belitsky, Victor, 1955, et al.
(författare)
-
Terahertz Instrumentation For Radio Astronomy
- 2009
-
Ingår i: International Symposium on Terahertz Science and Technology between Japan and Sweden. ; , s. 28-29
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Radio Astronomy was always a frontrunner in the demand on terahertz technology. Millimetre and sub-millimetre wave receivers operate at ground-based observatories for more than 20 years with real Terahertz instruments making its way to ground-based [1] and space-based observatories, e.g., Herschel HIFI, during last years.In this talk, we will look at the key requirements to the radio astronomy and environmental science terahertz receivers using heterodyne technology. The most promising and established technologies for high-resolution spectroscopy instrumentation will be discussed. Using results of the Group for Advanced Receiver Development for Onsala Space Observatory 20 m telescope, for Atacama Pathfinder Experiment (APEX) telescope and ALMA Project Band 5, we will illustrate the trends and achievements in the terahertz instrumentation for radio astronomy.
|
|
| 4. |
- Billade, Bhushan, 1982, et al.
(författare)
-
ALMA Band 5 (163-211 GHz) Sideband Separating Mixer Design
- 2008
-
Ingår i: in Proceedings of The 19th International Symposium on Space Terahertz Technology, Groningen, 28-30 April 2008, ed. W. Wild, Space Research Organization of the Netherlands (SRON). ; part I, s. 250-252
-
Konferensbidrag (refereegranskat)
|
|
| 5. |
- Billade, Bhushan, 1982, et al.
(författare)
-
ALMA Band 5 (163-211 GHz) sideband separation mixer design
- 2008
-
Ingår i: Proceedings of the 19th International Symposium on Space Terahertz Technology, ISSTT 2008. ; , s. 231-233
-
Konferensbidrag (refereegranskat)abstract
- We present the design of ALMA Band 5 sideband separation mixer based on Niobium superconducting SIS junctions and first experimental results for the double side band mixer. In this mixer the LO injection circuitry is integrated on the mixer substrate using a microstrip line directional coupler with slot-line branches in the ground plane. The isolated port of the LO coupler is terminated by a wideband floating elliptical termination. The mixer employs two SIS junctions with junction area of 3 ?m2 each, in twin junction configuration, followed by a quarter wave transformer to couple it to the RF probe. First measurements of the DSB mixer show promising results with noise temperature around 35K over the entire band.
|
|
| 6. |
- Dochev, Dimitar Milkov, 1981, et al.
(författare)
-
Superconducting IF biasing circuit for low-noise cryogenic applications
- 2010
-
Ingår i: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 234:4
-
Konferensbidrag (refereegranskat)abstract
- A planar superconducting circuit designed for use in low-noise cryogenic applications is presented. The circuit is a bias-T combined with a 4–8 GHz impedance matching circuitry, which employs entirely planar design with a novel layout. The proposed and tested circuitry is intended to be used with a SIS mixer and incorporates a double section transformer based on microstrip line technology with a total impedance transformation of 5:1 within the frequency band. One of the transformer sections employs a three-line coupled line, which also serves as a DC block capacitor. The microstrip lines were manufactured using superconducting Nb metallization, which provides a conduction loss-free solution at the operation temperature of 4 K. S-parameter measurements at 4 K temperature were performed and found to be in a good agreement with the simulations. The device measured return loss is better than −10 dB within the frequency band. Furthermore, the circuit was tested as a part of 385 – 500 GHz double sideband heterodyne SIS receiver demonstrating a flat noise temperature response of 80 – 90 K over the entire IF band of 4 – 8 GHz.
|
|
| 7. |
- Lapkin, Igor, 1963, et al.
(författare)
-
Optics Design and Verification for the APEX Swedish Heterodyne Facility Instrument (SHeFI)
- 2008
-
Ingår i: In Proceedings of The 19th International Symposium on Space Terahertz Technology, Groningen, 28-30 April, 2008, ed. W. Wild, Space Research Organization of the Netherlands (SRON). ; Part I, s. 351-357
-
Konferensbidrag (refereegranskat)abstract
- We present the design and verification of the receiver optics for the Single-Pixel HeterodyneFacility Instrument (SHFI) of the APEX telescope [1]. The SHFI is designed to cover thefrequency band 211 – 1390 GHz in 6 receiver channels. Four of the receiver channels have beendesigned, installed and characterized: 211-275 GHz (Band 1); 275-370 GHz (Band 2); 385-500 GHz (Band 3); 1250-1390 GHz (Band T2). The first three bands employ 2SB SIS mixertechnology and Band T2 employs HEB mixers in a waveguide balanced mixer configuration.The entire optics design was driven by the receiver position in the telescope Nasmyth cabin“A” (Fig.1) and the aperture limit of Ø150 mm, introduced by the elevation encoder inside theNasmyth tube A. This layout and the telescope geometry (~ 6 m distance from the focal plane tothe Cabin A) lead us to choose a single-pixel configuration and required using intermediateoptics with long focal distances. The common optics path, coupling the receivers to theCassegrain sub-reflector, consists of the three offset ellipsoidal mirrors, M3, M6, M8s, and threeflat mirrors, F4, F5, and F7s. The combination M3 and M6 via flat F4, F5, creates a Gaussiantelescope, providing frequency-independent re-imaging of the antenna focal plane from theCassegrain cabin into the Nasmyth cabin A. Switching between channels is achieved by theprecision rotating of the active mirror M8s. The mirror M8s in combination with each channelactive mirror M10 provides re-imaging of the secondary onto the feed horn aperture of theselected channel. Such a configuration provides frequency independent illumination of thesecondary with the edge taper -12dB. The angular position of the flat mirrors F9 is adjustable andgives additional possibility of fine-tuning of the beam alignment from the common optics toevery receiver channels.Verification of the optical designthrough measurements is essential inorder to align the beams from thecryostat windows to the commonoptics to minimize loss in thequasioptical guiding system. In orderto verify the design of the cold optics(corrugated horn + M10) in terms ofGaussian beam parameters, a newwideband vector field measurementsystem was developed [2]. Vectorfield measurements were performedfor band 1, 2, and 3, and scalarmeasurements were employed for theTHz band.
|
|
| 8. |
- Monje, Raquel, 1979, et al.
(författare)
-
A 0.5 THz Sideband Separation SIS Mixer for APEX Telescope
- 2008
-
Ingår i: In Proceedings of The 19th International Symposium on Space Terahertz Technology, Groningen, 28-30 April, 2008, ed. W. Wild, Space Research Organization of the Netherlands (SRON). ; Part II, s. 439-443
-
Konferensbidrag (refereegranskat)abstract
- We present the design and the experimental results of a fixed-tuned sideband-separating superconductor-insulator-superconductor (SIS) mixer for 385 - 500 GHz. The sideband separation is achieved using a quadrature scheme, where two separate DSB mixer blocks are combined with an intermediate waveguide component containing the LO waveguide distribution circuitry and RF waveguide hybrid. The intermediate waveguide piece is fabricated by using copper micromachining, which gives dimensions’ accuracy better than 1 μm. The RF signal coming from the waveguide hybrid is coupled to the SIS junctions through an E-probe with integrated bias-T. We implemented an on-chip LO injection solution, where the LO coupler is integrated onto the mixer chip and fabricated together with the SIS junction and the tuning circuitry. The on-chip LO coupler is made as a combination of superconducting microstrip lines and slot-lines (branches), which gives almost a lossless solution. With the fabrication accuracy better than 0.5 μm by using optical lithography, the circuitry is proven to give a good performance following the simulations expectations.
|
|
| 9. |
- Monje, Raquel, 1979, et al.
(författare)
-
A 385-500 GHz SIS Mixer for APEX Telescope
- 2006
-
Ingår i: in "Millimeter and Submillimeter Detectors for Astronomy III", eds. J. Zmuidzinas, W.S. Holland, S. Withington, W.D. Duncan, Proceedings of SPIE. ; 6275, s. 19-
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)
|
|
| 10. |
|
|
