Researchers have announced an advance that could double the capacity of fiber-optic circuits, potentially opening the way for networks to carry more data over long distances while significantly reducing their cost.

Writing in the journal Science on Thursday, electrical engineers at the University of California, San Diego proposed a way to extend the range that beams of laser light in fiber-optic glass wires can travel and, in theory, achieve that dramatic improvement.

One way to understand the challenge of sending data through fiber-optic circuits is to imagine a person shouting to someone else down a long corridor. As the listener moves farther away, the words become fainter and more difficult to discern as they echo off the walls.

A similar challenge confronts the designers of networks that carry data. Beams of laser light packed densely in fiber-optic glass wires need to be both amplified and recreated at regular intervals to send them thousands of miles. The process of converting the optical ones from light to electricity and then back again is a significant part of the cost of these networks. The process also limits how much data they can carry.