Callisto développe des récepteurs radiofréquences cryogéniques pour les télécommunications spatiales et la radioastronomie. Nous recherchons un stagiaire pour participer à la modification d'un banc de test utilisé en interne afin de valider les performances des refroidisseurs cryogéniques utilisés par Callisto.
Le but est d'automatiser les cycles de test de charges thermiques lors de la validation des refroidisseurs.
Le stage démarrera par une phase d'étude puis se poursuivra avec la réalisation du système de contrôle automatique des cycles.
• Compréhension du fonctionnement du banc de test de refroidisseurs cryogéniques de Callisto
• Finalisation du cahier des charges interne
• Choix des composants d'automatisation
• Développement logiciel (NI Labview) du système de contrôle et de mesure automatique du banc
• Test et validation
Callisto is seeking to recruit an engineer to take charge of sales of RF products for SATCOM applications. The ideal candidate should be qualified to degree level in a relevant engineering subject and have at least three years experience in the SATCOMs industry, of which one year in a sales or marketing role. Reporting to the CEO he/she will be responsible for the commercialisation of RF products for ground stations which Callisto has been developing over the past five years.
Working as a consultant system engineer on the design and implementation of a complex space system project for one of Europe's flagship space projects for the 21st century. The European Polar System - Second Generation (EPS-SG) is a challenging programme requiring the best engineers Europe can muster. The System Engineering team will handle the complex task of stitching together major functional elements and ensuring end-to-end performance with large volumes of data flow. Working to established standards and procedures (ECSS) and using advanced tools for management of complex systems (DOORS), consultants will be responsible for defining and controlling interfaces between functional elements, verifying that high level system requirements are flowed down and implemented correctly, system design integrity is maintained and optimised throughout the development process.
The profile of candidate we are seeking is as follows:
• University degree in the domain of engineering, science, or equivalent.
• At least 5 years of experience in the field of engineering of space and/or ground system.
• Experience of large space systems (space and/or ground segment).
• Experience of interface management and definition.
• Familiarity with mechanisms and tools for detailed interface definition.
• Demonstrated capability to prepare and manage IRD and ICD.
Additionally, experience in the following would be considered an advantage:
• Experience in the area of Low-Earth Orbiting satellites (LEO).
• Experience in CORE design tool (from Vitech).
• Experience with DOORs.
The tasks and responsibilities of the successful candidate to be undertaken during the EPS-SG Phase C/D will typically include the following:
• Coordination and definition of technical interfaces with the external partners and service providers • Organise/hold meetings and workshops with external and major internal interface partners to establish interface details/agreements
• Maintain Interface Requirement Documents (IRDs) for all system interfaces (using DOORs).
• Identify the mechanisms to be used for detailed ICD definition (eg use of XML etc)
• Generate and maintain the system Interface Control Documents (ICD).
• Provide support to general system engineering activities:
• Analysis and trade off activities
• Preparation and maintenance of system technical specification ,documentation of system design and justification , ad hoc internal reviews , support to progress meetings, support IV&V activities
The Ka Band Cryo Feed Critical Design has been accepted by ESA and Callisto will start the manufacture of this receiver early in 2016.
The G/T of ESA DSA can be improved by 2.9dB at Ka Band.
The X Band Cryo Feed Preliminary Design has also been accepted by ESA and Callisto will start the detailed design of this receiver early in 2016.
The G/T of ESA DSA can be improved by 1.6dB at X Band.
Callisto is pleased to announce the successful delivery of a new cryogenic test Dewar system for testing of various types of small components including RF, optical, and electronics. This system is cryogen-free (no liquids), operates under high vacuum and uses a GM-type refrigerator (cryocooler). It can cool components down to 30K.
One of the main features of this system is the capability of automatic thermal cycling between +60°C down to below 40K within a very short time frame, typically less than 1h30.
This system is compatible with clean room ISO5 and includes 5 large ports located on the sides and on the top of the enclosure that can receive a variety of hermetic connections to reach the components under test. Two additional small ports are available on the bottom plate, which can also be used for a variety of electrical feedthroughs.
The Dewar mechanical design is very flexible. For instance it is possible to open only the lid of the Dewar, or the entire Dewar housing to access the components, as required by the test setup.
Callisto is pleased to announce that it has been awarded a contract by Morehead State University, Kentucky, USA to supply an X Band Cryo Compact Low Noise Amplifier (LNA). The equipment is to be installed on the existing 21m radio telescope at Morehead State and will used for receiving telemetry from the Lunar IceCube spacecraft which is due to be launched in 2018.
Lunar IceCube is a 6U CubeSat spacecraft designed to prospect for water in solid, liquid, and vapor forms from a low-perigee, highly inclined lunar orbit. It was selected through NASA's NestSTEP program. The program is a partnership between Morehead State University, NASA Goddard Spaceflight Center, JPL, the Busek Company, Vermont Tech, and Kentucky Space LLC. Lunar IceCube will be deployed during lunar trajectory by the Space Launch System and use an innovative RF Ion engine to achieve lunar capture and the final orbit to investigate the distribution of water on the lunar surface. Lunar IceCube will include a compact version of a Broadband InfraRed Compact High Resolution Spectrometer developed by GSFC.
Callisto is pleased to announce that it has been awarded a contract by
Thales Alenia Space, Toulouse to supply Low Noise Amplifiers (LNAs)
operating in the 25.5 to 27 GHz Band for the Meteosat Third Generation
(MTG) project. The LNAs will be installed in four antennas making up
the Missions Data Acquisition ground stations for MTG. The order
comprises the LNAs as well redundancy switching components and
associated Controller/Power Supply units.
In order to improve the G/T of ESA Deep Space Antennas (DSA) by 2dB, a new cryogenic receiver will be developed in collaboration with the University of Cantabria.
Callisto is pleased to announce that the manufacture of the prototype of a new "Compact", zero maintenance cryogenic receiver including the Caltech designed QRFH feed has started!
This new RF receiver is being developed to meet the VGOS specification for VLBI. It could also be used for more general radio astronomy applications.
The design is focused on low maintenance, very low power consumption with Noise Temperature performance that meets the VGOS requirements. This is a state-of-the-art piece of equipment for telescopes all over the world but with particular interest for those operated in remote locations where energy costs are high and maintenance logistics is particularly complex and expensive.
The preliminary design work, de-risking activities and detailed design work completed in 2014 have produced good results with the completion of resistance and leak tests on a large vacuum window and cryogenic and RF tests that showed correct operations of the QRFH feed and LNAs at cryogenic temperatures.
The expected performance of the compact QRFH cryogenic receiver is confirmed but more importantly the de-risking work showed that the receiver can be operated at a better noise temperature than initially expected.
At the end of 2014 Callisto has delivered three additional X Band Compact maintenance free cryo LNAs.
These LNAs have 18K of Noise temperature between 8 and 8.5GHz.
To learn more on Maintenance free Cryo LNA follow this link