GMV has been awarded the contract to develop the SKA telescopes’ Timescales

The SKA Observatory will be the largest radio-astronomy facility on Earth, with two telescope arrays currently under construction in remote areas of Western Australia and South Africa The Timescale is the “heartbeat” of each telescope, generating highly stable time and frequency signals from atomic clocks, which are distributed to the remote antennas over optical fibre for synchronisation

GMV has been awarded a contract to develop the Timescales for the SKA Observatory’s (SKAO’s) two ground-breaking telescopes. The SKAO is an intergovernmental organisation with its Global Headquarters in the UK, at the historic site of Jodrell Bank Observatory near Manchester. The SKAO’s mission is to build and operate cutting-edge radio telescopes to transform our understanding of the Universe, and to deliver benefits to society through global collaboration and innovation.

The SKA telescopes will cover two different frequency ranges. SKA-Mid, an array of 197 traditional dish antennas, is being built in South Africa’s Karoo region, while SKA-Low, an array of 131,072 smaller tree-like antennas, is being built in Western Australia, on Wajarri Yamaji Country. For each telescope, the individual dishes and antennas work together as a huge array, with signals being digitally combined. The arrays will both be spread across large distances, with the most distant antennas being separated by 150km in South Africa, and 74km in Australia.

Using cutting-edge technology, including some of the fastest supercomputers in the world, they will make it possible to study the Universe in exquisite detail, revealing the environments around black holes, tracking the journeys of gravitational waves, and enabling a host of other ambitious science investigations.

Due to the sheer volume of data that will have to be transported, processed, stored, and distributed to end users around the globe, the SKA project is considered by many the ultimate Big Data challenge. An average of 8 terabits per second of data will be transferred over hundreds of kilometres from the telescopes. This is around 65,000 times faster than the estimated average home broadband speed in 2023.

Because signals from space reach each antenna at a slightly different time, the signals must first be aligned. This is achieved thanks to highly precise atomic clocks that timestamp the arrival of each signal. Each SKA telescope (SKA-Mid and SKA-Low) operates a central clock system called the Timescale. Each Timescale is composed of three ultra-stable clocks called hydrogen masers, plus ancillary hardware, and software.

The signals produced by the masers are continuously compared with one another to identify inaccuracies and are also compared and aligned via satellite with UTC time kept by the International Bureau of Weights and Measures (BIPM).

To support SKAO’s mission, under this contract GMV will design, manufacture, install and commission an operational Timescale for time distribution at the two SKA telescope sites. The project will run from February 2024 until October 2027. GMV will deploy the operational SKA-Mid timescale in South Africa in February 2026 and the SKA-Low timescale in Australia in June 2026. The deployment is followed by a period of monitoring and support.

Ricardo Píriz, Head of the Time and Frequency Division at GMV, UK said: “GMV has been collaborating with the international time metrology community for over 20 years. We maintain our own atomic timescale, which is aligned to UTC within a few nanoseconds, and is used operationally to monitor the accuracy of the time disseminated by GPS and Galileo, among other purposes. The SKA Timescales project is a game changer for GMV and an excellent opportunity for us to take our expertise in time and frequency generation and distribution to the next level. We are thrilled to work together with SKAO to deliver an excellent clock system for the SKA telescopes.”

Jill Hammond, SKA-Low Project Manager for Synchronisation, Timing and Networks said: “The SKA timescale is a fundamental component of the telescope system, and our requirements are very demanding. Given the importance of precise time within the telescopes, it was critical that we implement, manage, operate, and maintain our own timescale; we cannot do that with an “off the shelf” solution, so GMV’s timescale is customised for our unique requirements. We are looking forward to collaborating with GMV in realising this ambitious project and in delivering a first-of-a-kind solution.”

For more information visit: www.gmv.com