Not OP, so I'm guessing purely on my knowledge of how most of the industry works, but there's likely some sort of FPGA with custom IP at the center, connected to a powerful optical transmitter/receiver.

Associated reading can be found here: https://www.esa.int/Enabling_Support/Space_Engineering_Techn...

https://ntrs.nasa.gov/api/citations/20150009433/downloads/20...

https://www.fierceelectronics.com/electronics/fpga-enables-h...