Infrastructures and Equipment
Basic equipment for all RAEGE Core Site is:
- 1 radio telescope of VGOS specifications (13.2 m antenna diameter; operation with frequencies ³ 45 GHz and up to 90 GHz; fast slewing speed)
- 1 permanent GNSS station
- 1 gravimeter
- Maser clock
- 1 Seismograph/accelerograph
Radioastronomers detect very weak signals emitted by objects very far from Earth. Instruments used in land-based radio astronomy are large antennas or antenna networks equipped with the most sensitive receivers available, i.e., the noise they produce should be minimal to avoid its overlap to the signals received. Usually radio astronomy receivers are cooled to very low temperatures since some of the electronic devices used to amplify or mix radio signals add less noise if they are cooled.
In the frequency range of 500 MHz to 50 GHz, the components most often used at the entrance of these receptors are amplifiers with high electron mobility transistors (High Electron Mobility Transistors - HEMTs). These devices can be cooled to cryogenic temperatures (~15 Kelvin = -258° Celsius) for minimal noise. Once the weak radio astronomy signal is amplified, it is relatively immune to noise added in later processes.