TAMPA, Fla. — Canada’s Kepler Communications announced May 14 that it has successfully demonstrated optical data links between a prototype satellite in low Earth orbit (LEO) and a partner’s ground station for the first time.
Mina Mitry, Kepler’s CEO, said data was transferred using an optical ground station operated by French technology firm Cailabs at rates meeting standards set by the U.S. Space Development Agency, which is building a network of satellites connected by inter-satellite laser terminals to enhance space-based communications.
The demonstration marks another milestone in Kepler’s plans to build a high-capacity relay network, following tests last year that moved terabytes of data across two LEO pathfinders using optical inter-satellite links.
“We demonstrated tracking and data transfer through both near-horizon, where atmospheric effects are most severe, and high elevations, where tracking rates are the highest,” Mitry said via email.
“Demonstrating space-to-ground links using SDA standard derisks most of the elements (pointing, atmospherics) for our operational constellation and use of optical feeder links.”
Currently, satellites predominantly rely on radio frequency (RF) links for data transfer, but these systems face physical and regulatory constraints that limit their ability to meet the rapidly growing data demands of space infrastructure.
Available RF spectrum cannot adequately support data rates reaching into the tens of gigabits per second, according to Kepler.
While moving to extremely high frequencies could provide additional bandwidth, the company notes this approach introduces further technological maturity challenges due to the limited availability of commercial components.
At these higher frequencies, RF systems are also susceptible to the atmospheric and cloud interference issues faced by optical communications.
In contrast, Kepler says optical-to-ground systems offer virtually unlimited bandwidth. Optical beams can also be focused far more tightly than RF signals, making them more energy efficient.
Mitry added that successfully achieving space-to-ground optical communications paves the way for future tests involving space-to-air and cross-plane optical links.
