Major upgrade of international LOFAR telescope approved

News | February 6, 2023

The ILT Board has approved the order for the LOFAR2.0 upgrade of all 52 stations plus 2 additional stations of the International LOFAR Telescope (ILT), plus spare parts. A total investment of 10 million euros goes to orders from the Dutch companies Neways, Major Electronics, Variass and Batenburg Industrial Electronics.

The International LOFAR Telescope (ILT) consists of several stations with dozens of LBA (low band) and HBA (high band) antennas and is currently the largest radio telescope in the world, operating at the lowest frequencies observable from Earth . The ILT consists of a total of tens of thousands of antennas that jointly observe the universe and is a collaboration between ten countries: the Netherlands (38 stations), Germany (six stations), Poland (three stations), France, Ireland, Latvia, Sweden and the United Kingdom (one station each), with new stations coming soon in Italy and Bulgaria. 

Lofar 2k18 Screengrabs 23

At the time of construction, the system offered the ability to observe at any time from either the LBA or the HBA antennas (observing the LBA antennas at a frequency ranging from 10 to 80 MHz; observing the HBA antennas at a frequency ranging from 110 to 240 MHz). The LOFAR2.0 upgrade allows the telescope to use all LBA and HBA antennas simultaneously, increasing the field of view and sensitivity of the stations. A new digital processing board will replace the existing boards to handle the larger amount of data that LOFAR2.0 will produce. Finally, at the Dutch LOFAR stations, the distributed clock system will be replaced by a central clock signal distributed via a White Rabbit optical fiber network.

Most hardware manufactured by Dutch companies

An important part of the LOFAR2.0 upgrade is a hardware upgrade of all LOFAR stations. The majority of these hardware upgrades will be ordered from the Dutch companies Neways (Leeuwarden), Major Electronics (Hoogeveen), Variass (Veendam) and Batenburg Industrial Electronics (Neede).

Neways will introduce the new digital processing boards UniBoard2 produce. This board uses the latest generation of FPGAs (Field-Programmable Gate Arrays) and makes the LOFAR radio telescope suitable for processing more data and doing it faster. The Uni board2 forms the heart of the LOFAR2.0 telescope and carries out very complex processes.

Major Electronics will produce three modules for the new LOFAR2.0 system. The company from Hoogeveen will be responsible for the production of the CCD (Cabinet Clock Distribution) Module, the LMP (LOFAR Mid-Plane) printed circuit board and the APSPU (Antenna Processing Subrack Power Unit) Module. 

This new system also requires above average quality of the Printed Circuit Board Assemblies (PCBAs). Therefore, the latest AOI (Automated Optical Inspection) device will be used to check each PCBA for the quality of parts assembly. In addition, these PCBAs will undergo extensive testing before they are finally installed and commissioned.

For Major Electronics, the manufacture of these PCBAs is an opportunity to show that even complicated modules can be produced by a local manufacturer. By using high-tech SMD (Surface Mount Device) machines and Selective Wave Soldering technology, the quality of these modules will be as high as possible.

Variass will manufacture the receiver modules (RCU2) for the telescope, 6,000 in total. The LBA and HBA antennas each have a different type of receiver: RCU2L and RCU2H respectively. The RCUs amplify the antenna signals and allow astronomers to select specific frequency ranges.

After the amplification and filtering of the analog signal, the signal is digitized by the analog-to-digital converter (ADC) and sent to the Uniboard2 sent for further signal processing via the LMP module. Each RCU2 module separately processes three antenna signals.

Batenburg Industrial Electronics is responsible for the manufacture of the APSCT modules (Antenna Processor Subrack Clock distribution and Translator). These modules distribute the highly accurate and stable drive clock to the various modules within the drive subrack. Batenburg Industrial Electronics was also involved in the development of the APSCT module by manufacturing the first prototypes and will produce more than 200 modules for LOFAR2.0.

Production and delivery of the modules is expected at the end of 2023 and will also take place in the first half of 2024.