Sony Computer Science Laboratory (Sony CSL) and Japan’s National Research and Development Corporation (JAXA) successfully conducted a demonstration experiment, that is, under simulated low-quality and error-prone complete transfer of a data file in the communication environment.
Completing data transmission in harsh and complex environments is the key to future stratospheric and low-Earth orbit optical communications, and Sony CSL and JAXA have laid the technical foundation for the commercialization of this technology. The experiment is part of JAXA’s Space Innovation Partnership (J-SPARC).
In order for free-space optical communications to be better applied to the stratosphere and beyond extreme altitudes, communications equipment must be small, energy-efficient, and capable of high-speed transmission. In addition, the long-distance between communication devices means that any change in their orientation may result in the sending device’s laser signal not being stably received by the receiving device.
Signal noise can also be present in the environment and in the receiving equipment, causing signal encoding errors. For this reason, the standard suite of Internet protocols (TCP/IP) cannot ensure a stable communication link between devices in such an environment.
The collaboration between Sony CSL and JAXA aims to establish an internet service based on optical communication between low-orbit satellites and drones, enabling communication in the stratosphere. The two sides simulated an experimental environment built on a Gigabit Ethernet line with the bit error rate of free-space optical communication.
In this low-quality environment, ordinary Internet communication cannot be accomplished. However, the experimental data was successfully transmitted at a speed of 446 Mbps without any damage. This result suggests that optical communication in free space also has the potential to achieve high-quality and high-speed communication similar to terrestrial Internet services.
This communication adopts a signal processing method that combines Sony CSL’s Forward Error Correction (FEC) and JAXA’s Delay/Disruption Tolerant Network (DTN). Laser reading technology. This successful demonstration experiment means that point-to-point optical Internet services in stratosphere or low-Earth orbit can achieve high speed, high bandwidth and low energy consumption.
This will be a new commercial opportunity for future communication services, such as small optical communication terminals installed on constellations of low-Earth orbit satellites, or drones for stratospheric communication. Sony CSL and JAXA plan to continue joint research and development to achieve high-quality space communication services.