Radio Astronomy Receivers System and Technology

1. The 100m dish of our Telescope concentrates the electromagnetic signal coming from celestial sources into one point: the primary focus. In this focus point, we are able to locate different receiving systems to get the collected signal amplified and sampled into digital data streams. Removing these receivers from the primary focus a secondary mirror reflects the waves into a secondary focus point where another bundle of receiver systems are permanently installed. The task of the Systems Group is to operate, control & monitor, maintain and repair these receiver systems.
2. The receivers used in radio astronomy are mostly heterodyne receivers where the incoming frequency band is converted into one or more lower frequency bands the so called intermediate frequency (IF). The down conversion is done with local oscillators which are all phase locked to our Maser Reference Frequency system. Only at low frequencies up to some GHz, we omit down conversion by sampling the radio signal at the original frequency. The signal power level at the input of radio astronomy receivers is commonly very low, of order of -100 to -150 dBm. This means that high sensitivity and low receiver noise is one of the first requirements of the receivers.