The NorSat-TD demonstration microsatellite, crafted by Space Flight Laboratory (SFL) for the Norwegian Space Agency (NOSA), has achieved a groundbreaking milestone by successfully transferring data to a ground station using optical communications technology. This achievement marks a significant advancement, as it is the first instance of a Dutch-built laser communication device achieving such a feat and one of the initial accomplishments in the field by a microsatellite.
Optical, or laser, communications offer a superior alternative to traditional radio communications between satellites and ground stations. This technology facilitates faster and more secure transmission of larger datasets, which is crucial for a variety of low Earth orbit applications. These applications include Earth observation, telecommunications, atmospheric monitoring, maritime ship tracking, and space astronomy.
Dr. Robert E. Zee, Director of SFL, emphasized the significance of this achievement, stating, “The successful demonstration of satellite-to-ground communication by the 35-kg NorSat-TD microsatellite greatly expands the utility of affordable smaller satellites that are more cost-effective than traditional spacecraft to develop, launch, and operate.”
The success of optical satellite communications relies on two critical technologies. Firstly, precise attitude control is essential, especially for low-mass spacecraft like NorSat-TD. This allows the microsatellite to accurately and continuously point at the ground station as it passes overhead at a rapid speed of 7.5 km per second. SFL’s NorSat-TD incorporates advanced small satellite stability and pointing capabilities, honed through numerous operational missions.
The second crucial technology is a high-quality onboard laser terminal with a fine steering mirror, enabling the locking of an extremely narrow optical beam onto a ground station beacon. The Small Communication Active Terminal (SmallCAT) laser communication system aboard NorSat-TD was developed by a consortium led by TNO (The Netherlands Organization for Applied Scientific Research) of the Netherlands.
Tyler Jones, NOSA Senior Advisor, commended the success of the NorSat-TD optical communications demonstration, praising SFL’s DEFIANT bus’s pointing performance and acknowledging SFL’s flexibility and problem-solving in integrating the SmallCAT terminal into the NorSat-TD design.
Launched in April 2023, NorSat-TD, the sixth mission developed by SFL for Norway, was primarily designed for maritime ship tracking. In addition to this mission, the microsatellite carried experimental payloads for enhanced GPS positioning, spacecraft tracking by laser, iodine-fueled propulsion, and the SmallCAT terminal. The upcoming NorSat-4, currently under development at SFL for a 2024 launch, will feature a pioneering low-light imaging sensor.