For the past 2 years, Celestia Callisto has been working on an entirely new design. We are delighted to announce that an important space agency in Asia contracted with us to create a customized system for a new radio telescope. This design has come to fruition in the form of the first unit of a new, rotating cryogenic platform equipped with cartridges for the RF component.
Designed to be installed just after the primary signal entry, the unit’s table will actually rotate 180° to align one of the two cartridges in front of the waveguide entry.
In practice, a heavy-duty frame supports a drive ring which is adjustable along x, y and z axes. This drive ring, attached to an electric motor supports the disc-shaped cryostat. A laser telemetry system ensures accurate positioning (to a resolution of 30µm!). Instead of requiring more complicated higher-loss systems like beam waveguide based on dichroic mirrors, the rotating platform will allow the end user to position the appropriate receiver in front of the signal and thus optimize signal reception. While certain radio telescopes such as ALMA are indeed already equipped with a cartridge system, the Celestia-Callisto design is the first to simplify the front-end architecture by adding a rotating platform. This also has the very distinct advantage of reducing the amount of space required in the antenna hub, where extra surface is often in short supply!
This unit has two slots for RF cartridges, but future units could be designed for more. Each cartridge will have three thermal stages – the very top cooled to 15K, the median to 100k and the lowest, which is outside of the cryostat, will be at room temperature. Cryogenic cooling of these components reduces tremendously the additive thermal noise that physically results from every high-loss RF component exposed to a given physical temperature and thus improves the quality of the signal received. The system’s physical temperature is directly correlated with the amount of noise. Simply put, the colder the better.
Validation and testing of this rotating cryogenic cartridge system are progressing smoothly. Our engineers are confident that we will be able to push this technology to the limits, and maybe even beyond! We are extremely proud of this new achievement and look forward to its implementation.