The Radio Group develops systems that efficiently receive and transform electromagnetic waves from the Universe to electronical signals suitable for computer processing.
Most signals we receive from the Universe are very weak. To detect these signals we develop large fields of small antennas, that together, have a better receiption of signals. The design of the antenna takes into account the building location and the strong interfering signals of, for example, satellites, airplanes and mobile phones. Beam forming (electronically aiming the antenna beam) and calibration of the system are also part of the design.
Low noise amplifiers
The broadband low noise amplifier is the first amplifier after the antenna. High demands are set for this amplifier, which the Radio Group designs and tests. ASTRON has extensive facilities at its disposal to carefully characterise and analyse the amplifier.
The receiver translates the received signal to a different frequency band so it can be digitized. The challenge of making a good receiver lies in the broadband of the system and the desired dynamic reach. Components used in this broadband receiver are amplifiers, mixers and filters.
Building and testing
The low noise amplifiers and other components are built and tested in the Radio Lab. It's even possbile to connect chips to a print with gold threads, this way we can test if the chips meet the demands. Other characteristics, such as noise number and linearity, are carefully measured with noise measure equipment and spectrum analyzers. When the complete circuit works, the prototypes can be measured outside on our test field.
After all the verifications and measurements, all evidence is judged by a team of experts. When everyone is happy and there are no other obstacles, a new instrument can be built. This offers radio astronomers the chance to use a new instrument and make new discoveries.