Scientists at the University of California, San Diego, have managed to break the “capacity limits” of fiber optic networks. They increased the power of optic signals by almost 20 times the base level. Researchers managed to send the information a record-breaking 7,400 miles without the need of costly electronic regenerators to boost up the signals. The scientists developed wideband “frequency combs” that essentially keeps signal distortions and interference predictable so that it could be reversed successfully when the signal reached its destination.
Source: https://thehackernews.com/2015/06/optical-fiber.html

