| 1. |
- Andersdotter, Amelia, et al.
(författare)
-
Godtyckligt regelverk hotar friheten på nätet
- 2013
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Ingår i: Dagens Nyheter. - 1101-2447. ; :2013-09-03
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Tidskriftsartikel (populärvet., debatt m.m.)abstract
- Reglerna som möjliggör stängning av hemsidor på internet präglas av godtycke och otydlighet. Men det behöver inte vara särskilt svårt att skapa ett nytt och rättssäkert regelverk. Här har Sveriges EU-kommissionär Cecilia Malmström en viktig roll. Frågan är om hon tar sitt ansvar, skriver politiker och nätdebattörer.
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| 2. |
- Belitsky, Victor, 1955, et al.
(författare)
-
A new 3 mm band receiver for the Onsala 20 m antenna
- 2015
-
Ingår i: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 580
-
Tidskriftsartikel (refereegranskat)abstract
- A new receiver for the Onsala 20 m antenna with the possibility of being equipped with 3 mm and 4 mm bands has been built and the 3 mm channel has been commissioned during the Spring 2014. For single-dish operation, the receiver uses an innovative on-source/off-source optical switch. In combination with additional optical components and within the same optical layout, the switch provides two calibration loads (for the 3 mm and 4 mm channels), sideband rejection measurement, and tuning possibilities. The optical layout of the receiver employs all cold (4 K) offset elliptical mirrors for both channels, whereas the on-off switch employs flat mirrors only. The 3 mm channel employs a sideband separation (2SB) dual polarization receiver with orthomode transducer (OMT), 4-8 GHz intermediate frequency (IF), x? 2pol x? upper and lower sidebands (USB? +? LSB). The cryostat has four optical windows made of high density polyethylene (HDPE) with anti-reflection corrugations, two for the signal and two for each frequency band cold load. The cryostat uses a two-stage cryocooler produced by Sumitomo HI? RDK? 408D2 with anti-vibration suspension of the cold-head to minimize impact of the vibrations on the receiver stability. The local oscillator (LO) system is based on a Gunn oscillator with aphase lock loop (PLL) and four mechanical tuners for broadband operation, providing independently tunable LO power for each polarization. This paper provides a technical description of the receiver and its technology and could be useful for instrumentation engineers and observers using the Onsala 20 m telescope.
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| 3. |
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| 4. |
- Belitsky, Victor, 1955, et al.
(författare)
-
ALMA Band 2 Cold Cartridge Assembly Design
- 2022
-
Ingår i: 32nd International Symposium of Space Terahertz Technology, ISSTT 2022.
-
Konferensbidrag (refereegranskat)abstract
- As part of the ALMA development, we present the design of the ALMA Band 2 Cold Cartridge Assembly (CCA). The Band 2 is the last band that completes the suit of the 10 receiver channels of ALMA. The originally planned ALMA Band 2 receiver cartridge should cover the RF band of 67 - -90 GHz. The recent progress in technology, optics, OMT design and mm-wave amplifiers, however allowed to implement receiver that has an extended RF band up to 116 GHz. Furthermore, the Band 2 receiver pursues 2SB layout and provides 4-18 GHz IF band for two sidebands in a dual-polarization configuration. Here, we describe the design of the Band 2 CCA that includes optics, amplifier assembly, internal RF transport, mechanics and cryogenics. The downconverter part and performances are described elsewhere.
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| 5. |
- Belitsky, Victor, 1955, et al.
(författare)
-
ALMA Band 5 receiver cartridge: Design, performance, and commissioning
- 2018
-
Ingår i: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 611
-
Tidskriftsartikel (refereegranskat)abstract
- We describe the design, performance, and commissioning results for the new ALMA Band 5 receiver channel, 163-211 GHz, which is in the final stage of full deployment and expected to be available for observations in 2018. This manuscript provides the description of the new ALMA Band 5 receiver cartridge and serves as a reference for observers using the ALMA Band 5 receiver for observations. At the time of writing this paper, the ALMA Band 5 Production Consortium consisting of NOVA Instrumentation group, based in Groningen, NL, and GARD in Sweden have produced and delivered to ALMA Observatory over 60 receiver cartridges. All 60 cartridges fulfil the new more stringent specifications for Band 5 and demonstrate excellent noise temperatures, typically below 45 K single sideband (SSB) at 4 K detector physical temperature and below 35 K SSB at 3.5 K (typical for operation at the ALMA Frontend), providing the average sideband rejection better than 15 dB, and the integrated cross-polarization level better than -25 dB. The 70 warm cartridge assemblies, hosting Band 5 local oscillator and DC bias electronics, have been produced and delivered to ALMA by NRAO. The commissioning results confirm the excellent performance of the receivers.
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| 6. |
- Belitsky, Victor, 1955, et al.
(författare)
-
Design and performance of ALMA band 5 receiver cartridge
- 2010
-
Ingår i: 35th International Conference on Infrared Millimeter and Terahertz Waves (IRMMW-THz), 2010. - 9781424466559 ; , s. 1-2
-
Konferensbidrag (refereegranskat)abstract
- ALMA, Atacama Large Millimetre Array, covers the frequency band from 30 GHz to 960 GHz in ten separate frequency bands. We present here the design and performance of the ALMA Band 5 receiver cartridge that covers 163–211 GHz. The Band 5 receiver shows the state-of-the-art performance with the noise temperature below 65K (SSB) and sideband rejection above 12 dB over 80% of the RF band.
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| 7. |
- Belitsky, Victor, 1955, et al.
(författare)
-
Facility Heterodyne Receiver for the Atacama Pathfinder Experiment Telescope
- 2007
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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
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Konferensbidrag (refereegranskat)
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| 8. |
- Belitsky, Victor, 1955, et al.
(författare)
-
Prototype ALMA Band 5 Cartridge:Design and Performance
- 2009
-
Ingår i: Proceedings of the 20TH INTERNATIONAL SYMPOSIUM ON SPACE TERAHERTZ TECHNOLOGY, Charlottesville, VA, USA, April 20-22, 2009, s. 2-5.
-
Konferensbidrag (refereegranskat)abstract
- The Atacama Large Millimeter/submillimeterArray (ALMA), an international astronomy facility, is apartnership of East Asia, Europe and North America incooperation with the Republic of Chile and aims to build aninterferometer radio telescope consisting of more than 60antennas. The instrument is under construction at the Llano deChajnantor, about 50 km east of San Pedro de Atacama, Chile.This work presents a part of ALMA frontend, the development,design and performance of one of the frequency channels of theALMA receiver, the Band 5 prototype cartridge for 163 – 211GHz frequency band.
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| 9. |
- Belitsky, Victor, 1955, et al.
(författare)
-
SEPIA - A new single pixel receiver at the APEX telescope
- 2018
-
Ingår i: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 612
-
Tidskriftsartikel (refereegranskat)abstract
- Context. We describe the new Swedish-ESO PI Instrument for APEX (SEPIA) receiver, which was designed and built by the Group for Advanced Receiver Development (GARD), at Onsala Space Observatory (OSO) in collaboration with ESO. It was installed and commissioned at the APEX telescope during 2015 with an ALMA Band 5 receiver channel and updated with a new frequency channel (ALMA Band 9) in February 2016. Aim. This manuscript aims to provide, for observers who use the SEPIA receiver, a reference in terms of the hardware description, optics and performance as well as the commissioning results. Methods. Out of three available receiver cartridge positions in SEPIA, the two current frequency channels, corresponding to ALMA Band 5, the RF band 158-211 GHz, and Band 9, the RF band 600-722 GHz, provide state-of-the-art dual polarization receivers. The Band 5 frequency channel uses 2SB SIS mixers with an average SSB noise temperature around 45 K with IF (intermediate frequency) band 4-8 GHz for each sideband providing total 4 × 4 GHz IF band. The Band 9 frequency channel uses DSB SIS mixers with a noise temperature of 75-125 K with IF band 4-12 GHz for each polarization. Results. Both current SEPIA receiver channels are available to all APEX observers.
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| 10. |
- Belitsky, Victor, 1955, et al.
(författare)
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Terahertz Instrumentation For Radio Astronomy
- 2009
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Ingår i: International Symposium on Terahertz Science and Technology between Japan and Sweden. ; , s. 28-29
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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.
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| 11. |
- Billade, Bhushan, 1982, et al.
(författare)
-
ALMA band 5 cartridge performance
- 2010
-
Ingår i: 21st International Symposium on Space Terahertz Technology 2010, ISSTT 2010; Oxford; United Kingdom; 23 March 2010 through 25 March 2010. - 9781617823626 ; , s. 112-
-
Konferensbidrag (refereegranskat)abstract
- Work presented here concerns the design and performance of the ALMA Band 5 cold cartridge, one of the 10 frequency channels of ALMA project, a radio interferometer under construction at Atacama Desert in Chile. The Band 5 cartridge is a dual polarization receiver with the polarization separation performed by orthomode transducer (OMT) [1]. For each polarization, Band 5 receiver employs sideband rejection (2SB) scheme based on quadrature layout, with SIS mixers covering 163-211 GHz with 4-8 GHz IF. The LO injection circuitry is integrated with mixer chip and is implemented on the same substrate, resulting in a compact 2SB assembly. Amongst the other ALMA bands, the ALMA Band 5 being the lowest frequency band that uses all cold optics, has the largest mirror. Consequently, ALMA Band 5 mirror along with its support structure leaves very little room for placing OMT, mixers and IF subsystems. The constraints put by the size of cold optics and limited cartridge space, required of us to revise the original 2SB design and adopt a design where all the components like OMT, mixer, IF hybrid, isolators and IF amplifier are directly connected to each other without using any co-ax cables in-between. The IF subsystem uses the space between 4 K and 15 K stage of the cartridge and is thermally connected to 4 K stage. Avoiding co-ax cabling required use of custom designed IF hybrid, furthermore, due to limited cooling capacity at 4 K stage, resistive bias circuitry for the mixers is moved to 15 K stage and the IF hybrid along with an integrated bias-T is implemented using superconducting micro-strip lines. The E-probes for both LO and RF waveguide-to-microstrip transitions are placed perpendicular to the wave direction (back-piece configuration). The RF choke at the end of the probes provides a virtual ground for the RF/LO signal, and the choke is DC grounded to the chassis. The on-chip LO injection is done using a microstrip line directional coupler with slot-line branches in the ground plane. The isolated port of the LO coupler is terminated by floating wideband elliptical termination. The mixer employs two SIS junctions with junction area of 3 μm2 each, in twin junction configuration, followed by a quarter wave transformer to couple it to the signal probe. A quarter-wave high impedance line on an extra layer of SiO2 is used to extract the IF by separating from RF [2]. At the conference, we plan to present details of the cartridge design and results of the experimental characterization of the ALMA Band 5 cold cartridge.
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| 12. |
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| 13. |
- Billade, Bhushan, 1982, et al.
(författare)
-
Performance of the First ALMA Band 5 Production Cartridge
- 2012
-
Ingår i: IEEE Transactions on Terahertz Science and Technology. - 2156-342X .- 2156-3446. ; 2:2, s. 208-214
-
Tidskriftsartikel (refereegranskat)abstract
- We present performance of the first ALMA Band 5 production cartridge, covering frequencies from 163 GHz to 211 GHz. ALMA Band 5 is a dual polarization, sideband separation (2SB) receiver based on all Niobium (Nb) Superconductor-Insulator-Superconductor (SIS) tunnel junction mixers, providing 16 GHz of instantaneous RF bandwidth for astronomy observations. The 2SB mixer for each polarization employs a quadrature configuration. The sideband separation occurs at the output of the IF hybrid that has integrated bias-T for biasing the mixers, and is produced using superconducting thin film technology.Experimental verification of the Band 5 cold cartridge performed together with warm cartridge assembly, confirms that the system noise temperature is below 45 K over most of the RF band, which is less than five photon noise (5 hf/k). This is to our knowledge, the best results reported at these frequencies. The measurement of the sideband rejection indicates that the sideband rejection better than 10 dB over 90% of the observational band.
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| 14. |
- Billade, Bhushan, 1982, et al.
(författare)
-
Performance of the first ALMA Band 5 production cartridge
- 2011
-
Ingår i: Proceedings of the 22nd International Symposium on Space Terahertz Technology, April 26-28th, 2011 - Tucson, Arizona, USA. ; , s. 56-56
-
Konferensbidrag (refereegranskat)abstract
- We present performance of the first ALMA Band 5 production cartridge, covering RF frequencies from 163 GHz to 211 GHz. ALMA Band 5 is a dual polarization, sideband separation (2SB) receiver based on all Niobium (Nb) SuperconductorInsulator-Superconductor (SIS) tunnel junction mixer, providing 16 GHz of instantaneous RF bandwidth for the astronomy observations. The 2SB mixer for each polarization employs a quadrature layout. The sideband separation occurs at the output of the IF hybrid that has integrated bias-T for biasing the mixers, and is produced using superconducting thin film technology. Experimental verification of the Band 5 cold cartridge performed together with warm cartridge assembly, confirms the system noise temperature below 45 K, less than five quantum noise (5 hf/k) over most of the RF band, which is to our knowledge, the best results at these frequencies. The measurement of the sideband rejection indicates that the sideband rejection better than 10 dB over 90% of the observational band.
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| 15. |
- Ermakov, Andrey, 1960, et al.
(författare)
-
Broken-step Phenomenon in SIS Mixers
- 2016
-
Ingår i: 27th International Symposium on Space Terahertz Technology, ISSTT 2016, Nanjing, China.
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Konferensbidrag (refereegranskat)abstract
- In this paper, we discuss a “broken step” phenomenonin an SIS mixer. This phenomena was observed in the production version of the SIS mixers, designed for the 159-211 GHz RF band,being used for the construction of the ALMA Band 5 receiver The broken step typically appears at LO frequencies above 180 GHz and manifests itself as a sharp onset in the DC current at the middle of the quasiparticle step. Correspondingly, this affects the mixer IF response in a way that is similar to the Josephson step but is however of a different nature. Such behaviour affects the SIS mixer dynamic range and complicates the tuning of the 2SB mixer to optimize its performance, for both the receiver noise as well as the sideband rejection. In this paper, we describe results of a few experiments which were performed to understand this undesirable phenomenon.
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| 16. |
- Lapkin, Igor, 1963, et al.
(författare)
-
Dual Band MM-Wave Receiver for Onsala 20 m Antenna
- 2014
-
Ingår i: Proceedings of the TWENTY-FIFTH INTERNATIONAL SYMPOSIUM ON SPACE TERAHERTZ TECHNOLOGY, April 27-30, 2014, Moscow, Russia. ; , s. 132-
-
Konferensbidrag (refereegranskat)abstract
- We present the design and the first light results for the new dual band receiver (4 mm and 3 mm bands) for Onsala Observatory 20 m antenna. For single dish operation, the receiver uses innovative on-source/off-source optical switch. Within the same optical layout, the switch, in combination with additional optical components, provides 2 calibration loads and sideband measurements possibilities. The optics layout of the receiver uses offset elliptical cold mirrors for both channels whereas the on-off switch employs flat mirrors only. The 3 mm channel employs 2SB dual polarization receiver with OMT, 4-8 GHz IF, x 2pol x (USB+LSB). The cryostat has 4 optical widows made of HDPE with anti-reflection corrugations, two for the signal and two for each frequency band cold load. The cryostat employs a two stage cryocooler RDK 408D2 and uses anti-vibration suspension of the cold-head to minimize impact of the vibrations on the receiver stability. The LO system is based on Gunn oscillator with PLL and two mechanical tuners for broadband operation, providing independently tunable LO power for each polarization. At the conference, we will present details on the receiver optics, cryostat design and the result of the first on-sky observations.
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| 17. |
- Lapkin, Igor, 1963, et al.
(författare)
-
New optics for SEPIA- Heterodyne facility instrument for the APEX telescope
- 2019
-
Ingår i: ISSTT 2019 - 30th International Symposium on Space Terahertz Technology, Proceedings Book. ; , s. 150-154
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Konferensbidrag (refereegranskat)abstract
- The design of SEPIA (Swedish ESO PI Instrument for APEX) was driven by the idea of using ALMA receiver cartridges on the APEX telescope. SEPIA was installed at the guest position of the Naismith cabin A, APEX telescope in early 2015. The SEPIA cryostat and optics was designed to accommodate up to 3 ALMA cartridges. In 2017, the APEX facility instrument SHeFI was decommissioned and SEPIA was accepted as its successor. Moving SEPIA from its PI into Facility Instrument position brought additional constrains due to the severe limitations of the available space. That had led to the necessity of complete redesigning of the SEPIA tertiary optics. During February-March 2019, the new tertiary optics was installed in the APEX Cabin A and SEPIA was placed at its final Facility Instrument position. Here, we present the details of the optical design, layout of the optical component placement, the beam alignment technique, the results of the alignment and SEPIA technical commissioning results at the APEX telescope.
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| 18. |
- Lapkin, Igor, 1963, et al.
(författare)
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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.
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| 19. |
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| 20. |
- Meledin, Denis, 1974, et al.
(författare)
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A 1mM SIS receiver utilizing different intermediate frequency (IF) configurations
- 2019
-
Ingår i: ISSTT 2019 - 30th International Symposium on Space Terahertz Technology, Proceedings Book. ; , s. 164-167
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Konferensbidrag (refereegranskat)abstract
- We present experimental studies of the noise performance of a prototype heterodyne SIS receiver operating at wavelengths of about 1mm. The receiver employs different 4-12GHz intermediate frequency amplification chain configurations: a standalone low noise amplifier (LNA), the LNA cascading with a cryogenic isolator, and a low noise balanced amplifier. From our experiments and measurements, we could conclude that the latter configuration demonstrates the best broadband noise performance. In fact, the receiver equipped with the balanced LNA does not have noticeable noise degradation caused by the IF hybrids of the balanced LNA scheme. Moreover, our results indicate that even broader IF bandwidth of the receivers could be prospectively reached using balanced LNAs in the IF amplification chain.
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| 21. |
- Meledin, Denis, 1974, et al.
(författare)
-
APEX Band T2: A 1.25 – 1.39 THz Waveguide Balanced HEB Receiver
- 2008
-
Ingår i: 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. 162-166
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Konferensbidrag (refereegranskat)abstract
- A waveguide 1.25 - 1.39 THz Hot Electron Bolometer (HEB) balanced receiver was successfully developed, characterized and installed at the Atacama Pathfinder EXperiment (APEX) telescope. The receiver employs a quadrature balanced scheme using a waveguide 90-degree 3 dB RF hybrid, HEB mixers and a 180-degree IF hybrid. The HEB mixers are based on ultrathin NbN film deposited on crystalline quartz with a MgO buffer layer. Integrated into the multi-channel APEX facility receiver (SHeFI), the results presented here demonstrate exceptional performance; a receiver noise temperature of 1000 K measured at the telescope at the center of the receiver IF band 2-4 GHz, and at an LO frequency of 1294 GHz. Stability of the receiver is in line with the SIS mixer bands of the SHeFI, and gives a spectroscopic Allan time of more than 200 s at 1382 GHz with a noise bandwidth of 1 MHz.
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| 22. |
- Meledin, Denis, 1974, et al.
(författare)
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SEPIA345: A 345 GHz dual polarization heterodyne receiver channel for SEPIA at the APEX telescope
- 2022
-
Ingår i: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 668
-
Tidskriftsartikel (refereegranskat)abstract
- Context. We describe the new SEPIA345 heterodyne receiver channel installed at the Atacama Pathfinder EXperiment (APEX) telescope, including details of its configuration, characteristics, and test results on sky. SEPIA345 is designed and built to be a part of the Swedish ESO PI Instrument for the APEX telescope (SEPIA). This new receiver channel is suitable for very high-resolution spectroscopy and covers the frequency range 272- 376 GHz. It utilizes a dual polarization sideband separating (2SB) receiver architecture, employing superconductor-isolator-superconductor mixers (SIS), and provides an intermediate frequency (IF) band of 4- 12 GHz for each sideband and polarization, thus covering a total instantaneous IF bandwidth of 4 ÃÂ - 8 = 32 GHz. Aims. This paper provides a description of the new receiver in terms of its hardware design, performance, and commissioning results. Methods. The methods of design, construction, and testing of the new receiver are presented. Results. The achieved receiver performance in terms of noise temperature, sideband rejection, stability, and other parameters are described. Conclusions. SEPIA345 is a commissioned APEX facility instrument with state-of-the-art wideband IF performance. It has been available on the APEX telescope for science observations since July 2021.
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| 23. |
- Meledin, Denis, 1974, et al.
(författare)
-
SEPIA345: a dual polarization 2SB cartridge receiver for APEX telescope: Design and Performance
- 2023
-
Ingår i: Proceedings of the 32nd IEEE International Symposium on Space THz Technology.
-
Konferensbidrag (refereegranskat)abstract
- A new receiver channel covering the 271-377 GHz frequency band has been installed into the SEPIA receiver at the APEX telescope. The receiver channel was designed and built in an ALMA-compatible cartridge layout. The receiver has a dual polarization layout with OMT and employs 2SB SIS mixers featuring an extended 4-12 GHz IF band, providing 32 GHz instantaneous IF bandwidth for two polarizations and two sidebands.
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| 24. |
- Meledin, Denis, 1974, et al.
(författare)
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SEPIA345: a dual polarization 2SB cartridge receiver for APEX telescope: Design and Performance
- 2022
-
Ingår i: 32nd International Symposium of Space Terahertz Technology, ISSTT 2022.
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Konferensbidrag (refereegranskat)abstract
- A new receiver channel covering the 271-377 GHz frequency band has been installed into the SEPIA receiver at the APEX telescope. The receiver channel was designed and built in an ALMA-compatible cartridge layout. The receiver has a dual polarization layout with OMT and employs 2SB SIS mixers featuring an extended 4-12 GHz IF band, providing 32 GHz instantaneous IF bandwidth for two polarizations and two sidebands.
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| 25. |
- Nyström, Olle, 1979, et al.
(författare)
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Integrated Setup for THz Receiver Characterization
- 2010
-
Ingår i: 21st International Symposium on Space Terahertz Technology 2010, ISSTT 2010; Oxford; United Kingdom; 23 March 2010 through 25 March 2010. - 9781617823626 ; , s. P6-4
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Konferensbidrag (refereegranskat)abstract
- A highly versatile measurement setup has been built that allows complete characterization of the ALMA Band 5 cartridge. The measurement setup includes all necessary hardware and largely achieves automatic measurements for the system noise and sideband rejection with in-built optimization procedures. The measurement setup additionally comprises measurements of the receiver saturation, phase and amplitude stability, as well as optical beam characterization.
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| 26. |
- Nyström, Olle, 1979, et al.
(författare)
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Optics Design and Verificatgion for the APEX Swedish Heterodyne Facility Instrument (SHeFI)
- 2009
-
Ingår i: Journal of Infrared, Millimeter, and Terahertz Waves. - : Springer Science and Business Media LLC. - 1866-6892 .- 1866-6906. ; 30:7, s. 746-761
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Tidskriftsartikel (refereegranskat)abstract
- In this paper, we present the design and verification of the optics of the Swedish Heterodyne Facility Instrument (SHeFI) receiver installed in the Atacama Pathfinder EXperiment (APEX) telescope during spring 2008. SHeFI is located in the Nasmyth instrumentation Cabin A (NCA). The receiver has been designed to have 6 frequency channels, of which four receiver channels have been built, and characterized: 211-275 GHz(Band 1), 275-370 GHz (Band 2), 385-500 GHz (Band 3), and 1250-1390 GHz (Band T2). Bands 1, 2, and T2 are installed at the telescope and are currently in operation. The optical design is driven by the requirement of frequency independent illumination of the secondary with -12 dB edge taper for each frequency channel and the limitation (beam clearance through the Nasmyth tube and the elevation encoder) imposed by the receiver position in the NCA. This paper describes the design approach, optimization, and verification of the optical system, coupling each individual receiving beam to the common optics of the telescope.
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| 27. |
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| 28. |
- Risacher, C., et al.
(författare)
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A 279-381 GHz SIS Receiver for the APEX Telescope
- 2006
-
Ingår i: Proceedings of the 16th International Symposium on Space Terahertz Technology, Chalmers University of Technology, Gothenburg, Sweden, May 2-4, 2005. ; , s. 432-437
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)
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| 29. |
- Strandberg, Magnus, 1975, et al.
(författare)
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Setup for Measurement and Characterization of Cryogenic Low-Noise Receivers
- 2024
-
Ingår i: 2024 4th URSI Atlantic Radio Science Meeting, AT-RASC 2024.
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Konferensbidrag (refereegranskat)abstract
- In mm-wave and THz radio astronomy receivers, key components such as mixers, hybrids etc., needs to be fully characterized individually to ensure they fulfill requirement and specifications of various types. In this paper, we present details of a new measurement setup, built in the labs of the Group for Advanced Receiver Development (GARD) and a new underlaying software back-end for measuring, characterization and monitor any of the receiver's components. This software, called GMS GARD Measurement System, does allow several frontend graphical user interfaces (GUI) being written in different programming languages to connect and interact with the measurement setup simultaneously.
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| 30. |
-
Traces of Transnational Relations in the Eighteenth Century
- 2015
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Samlingsverk (redaktörskap) (refereegranskat)abstract
- Contents:Introduction - Mathias Persson and Annie MattssonCarrot and Stick: The Nordic Foreign Policy of Sir Robert Walpole - Phillip SargeantCompetition and Cooperation: Swedish Consuls in North Africa andSweden’s Position in the World, 1791–1802 - Fredrik KämpeCommunities, Limits and the Ability to Cross Borders: Two Swedes’Experiences in Constantinople during the Eighteenth Century - Karin BernerJohan Leven Ekelund – Equerry, Traveller and Writer - Anna BackmanThe Roast Charade: Travelling Recipes and their Alteration in the LongEighteenth Century - Helga MüllneritschBringing Into the Light, or Increasing Darkness With Darkness: Jacob Wilde’s Rewriting of Samuel Pufendorf’s Account of Swedish Ancient History - Tim BerndtssonL’Amour Raisonnable: Précieuse Perspectives on Love –Hedvig Charlotta Nordenflycht and the French Seventeenth-Century Salon - Vera Sundin
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- Vassilev, Vessen, 1969, et al.
(författare)
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A Swedish heterodyne facility instrument for the APEX telescope
- 2008
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Ingår i: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 490:3, s. 1157-1163
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Tidskriftsartikel (refereegranskat)abstract
- In March 2008, the APEX facility instrument was installed on the telescope at the site of Lliano Chajnantor in northern Chile. The main objective of the paper is to introduce the new instrument to the radio astronomical community. It describes the hardware configuration and presents some initial results from the on-sky commissioning.The heterodyne instrument covers frequencies between 211 GHz and 1390 GHz divided into four bands. The first threebands are sideband-separating mixers operating in a single sideband mode and based on superconductor-insulator-superconductor (SIS) tunnel junctions. The fourth band is a hot-electron bolometer, waveguide balanced mixer. All bands are integrated in a closedcycle temperature-stabilized cryostat and are cooled to 4 K.We present results from noise temperature, sideband separation ratios, beam, and stability measurements performed on the telescope as a part of the receiver technical commissioning. Examples of broad extragalactic lines are also included.
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