Current communication with satellites at long distances or with spaceships is fundamentally based on radiofrequency communication and free space laser communication with conventional wavelengths below 1600 nm.
We are proposing a new regime of communication based on high-energy laser operating at Short-Wave InfraRed (SWIR) wavelengths to achieve a more stable connection, high-speed data rate, and to provide optical data link with satellites in the deep space. Our proposed innovative SWIR laser solution is based on Ho:YAG (Holmium doped Yttrium Aluminum Garnet) thin disks emitting laser radiation around 2100 nm. This new wavelength together with the thin disk solution provides an enhanced range of use. It is lightweight and compact, allowing the system to be easily transported or carried on a smaller satellite. The SWIR laser operates in the water window for propagation in the atmosphere, requires less energy than standard systems, and allows both day and night operation thanks to lower solar irradiance in this wavelength region. The system does not require a clouds free sky to establish communication as it penetrates most clouds.
Our solution upgrades the standard lasers by providing the new wavelength, tunability, and improved mechanical properties that result in greater vibration stability and beam pointing. Better propagation through the atmosphere will result in advanced performance in communication with the satellites in the Earth’s orbit and long-distance missions.
Thanks to the operation in the 2100 nm wavelength region, the SWIR laser system is eye-safe which is an important feature when compared to the Nd:YAG lasers. We will build the core of the innovative SWIR laser running at tens of Watts and compare it with the standard lasers for communication. Though the commercially available detectors work currently up to 2500nm in the GHz bandwidth range, their sensitivity is limited. Commercially available detectors still need to be developed further.
