Dr. Nan Cen, assistant professor of computer science at Missouri S&T.

Household lights inspire bright ideas to fill broadband gaps

Mobile phones have become multipurpose devices over the past two decades, with capabilities including photo taking, location tracking, and surfing the internet. Have you ever wondered if your household lights could do more and become multipurpose devices as well? A Missouri University of Science and Technology computer scientist is working toward that.

Nan Cen is studying how to modulate visible light — turn it on and off faster than the human eye can detect — to transmit data over Wi-Fi. This method is faster than conventional data transmission technologies.

“An advantage of visible-light communication is the largely unregulated spectrum ranging from 375 terahertz to 750 terahertz, which would provide higher data-rate communication than current technologies,” said Cen, assistant professor of computer science at Missouri S&T, in a news release. “Another advantage is simplicity — using basic photo detectors to receive the data from standard room lights.”

Household lamps could be used in place of a router to transmit data. Visible-light communication also could be used for virtual reality, transportation, and drones.

One drawback is that visible-light communication has a short range. Household lights have a range of a few meters, whereas lasers could extend the range to several kilometers. Visible light also is easy to block, which could cause data transmission interruptions without anti-blocking solutions. 

Cen points out that not enough spectrum currently is available to handle the rapid growth in Internet of Things connected devices, and more technology is needed to process higher data rates with visible-light communication. But within the next 10 to 20 years, these devices could be equipped with light sensors, she says. 

That could help to fill high-speed broadband accessibility gaps, especially in rural areas. For example, lasers could be positioned in between light poles to serve as a light transmitter, and solar panels could be the receivers. 

More research and development is needed before visible-light communication infrastructure becomes a viable option. Few researchers in the U.S. focus on this topic, and Cen says more are needed to advance the sector. Greater industry interest and participation also is crucial to help develop compatible devices.

“We need to demonstrate that this is feasible technology that we definitely need,” Cen said.