Instead of using microwaves to transmit data wirelessly, Facebook is considering using a built-in laser detector to offer connections with speeds up to 2.1Gbps.
The Facebook Connectivity Lab at Facebook.org believes that the laser approach could, along with the drone used by the company, help to link four billion people, especially those living in remote and rural areas.
The researchers have managed to describe a new technique they call free-space optical (FSO) communication. The new technology can overcome the data transmission limitations of microwaves by expanding the available spectrum to much larger sizes. They demonstrated that they could transmit data with speed 2Gbps using 100MHz bandwidth.
The Facebook team borrowed a technique used to collect sunlight, and applied it for data transmission.
The collector absorbs blue light and emits green light. Facebook notes that fast speeds are possible due to the passing of less than two nanoseconds between absorption and emission of light.
"Optical fibers absorb light coming from any direction in a large region, and the emitted light travels through the optical fiber, which channels it into a small, very fast photodetector.”
"The fact that these fluorescent optical fibers emit a different color than they absorb makes it possible to increase the brightness of the light entering the system," said Tobias Tiecke, project manager.
“This approach has been used in luminescent condensers to collect sunlight, where the speed of color conversion does not matter. We have shown that the same idea can be used to communicate at very high speeds. "
According to Tiecke, Facebook is trying to build a prototype of the concept to test it in reality and explore whether its use can be expanded as commercial product.
