Another First: Isro enters X-band telemetry & command regime with Aditya-L1
Another First: Isro enters X-band telemetry & command regime with Aditya-L1
First Earth-Bound Manoeuvre Completed, Spacecraft In 245km x 22,459km Orbit
In this season of firsts, here’s another milestone relating to India’s first solar space observatory mission — Aditya-L1.
In a first, Isro is using the high throughput X-band frequency for telemetry and command functions for Aditya-L1, graduating from the S-band telemetry and command regime, in line with global standards for missions beyond the Earth’s sphere of influence.
So far, Isro has used X-band only for payload data downloading and used S-band for telemetry and command (monitoring of the satellite, communicating with it and issuing commands for tasks). Compared to S-band, which operates with 2-2.5GHz, X band functions with 8-8.5GHz.
The advantage of using X-band is that it allows for more clear communication with satellites that are far away. In the case of Aditya-L1, which completed the first of the five Earth-bound manoeuvres at 11.40am Sunday, the distance is 1.5 million-km.
After completing the first Earth-bound manoeuvre, Isro said: “The satellite is healthy and operating nominally. The new orbit attained is 245km x 22,459km and the second Earth-bound manoeuvre is scheduled for 3am on September 5.”
Telemetry Infrastructure
Aditya’s operations are being carried out by multiple tracking stations operated by Isro Telemetry, Tracking and Command Network (Istrac), headquartered in Bengaluru. It also includes a temporary station at Fiji Islands.
The main antenna supporting operations is the 18m antenna in Byalalu, some 30km from Bengaluru. Commissioned in 2021, the antenna was put in place using funds for the Aditya-L1 mission, which was designed to have X band telemetry.
It is equipped with auto-tracking features in both the bands and is remotely operable from Istrac network control centre and is CCSDS (Consultative Committee for Space Data Systems) compliant facilitating interoperability and cross-support among different space agencies.
Isro chairman S Somanath says: “We have used this even with Chandrayaan-3.” The antenna at Byalalu, developed by ECIL (Electronics Corporation of India Limited) with some key systems coming from BARC (Bhabha Atomic Research Centre), can operate in both S and X bands.
Isro has adopted the strategy of building stations that can use both bands as other missions — like remote sensing, communication satellite and commercial launches — use S band. Aside from the Byalalu antenna, Isro has at least two smaller antennas that can operate in both S and X bands.
The new infrastructure will also provide opportunities for Space PSU NewSpace India Limited (NSIL) to commercialise it in the future.
Aditya-L1 is scheduled to perform its second Earth-bound manoeuvre at 3am on September 5.
The next newsletter will discuss Aditya’s next op and a lot more about Chandrayaan-3’s life ending — at least temporarily for now — on Moon and how its lander Vikram performed a “short hop”.
Stay tuned!