Graduate students, Spencer Liverman and Qiwie Wang, demonstrate the WiFO prototype system as Thinh Nguyen, associate professor, looks on.
A new invention at Oregon State promises to increase the bandwidth of WiFi systems ten times by using LED lights to transmit information. The technology can integrate with existing WiFi systems to alleviate bandwidth problems in crowded locations such as airport terminals or coffee shops, and in homes where several people have multiple WiFi devices.
Recent advances in LED technology have made it possible to modulate the LED light more rapidly, which opened up the possibility of using light for wireless transmission in a free space optical communication system.
“Using light to transmit signals is an old technology that dates back when the Roman soldiers communicated with each other using a simple flash code with mirrors,” said Thinh Nguyen, associate professor of electrical and computer engineering and lead researcher for the project.
The system uses inexpensive components to send data at 100 Megabits per second (Mbps). Although some current WiFi systems have similar bandwidth it has to be divided by the number of devices, so each user might be receiving just 5 to 10 Mbps, whereas the hybrid system could deliver 50-100 Mbps to each user. In a home where phones, tablets, computers, gaming systems, and televisions may all be connected to the internet, increased bandwidth would eliminate problems like video streaming that stalls and buffers.
The prototype, called WiFO, uses LEDs that are beyond the visual spectrum for humans and creates an invisible cone of light about a meter square in which the data can be received. To work around the issue of a small area of effect, Nguyen and collaborators created a hybrid system that can switch between several LED transmitters installed on a ceiling, and the existing WiFi system.
The receivers are small photodiodes which cost less than a dollar each and could be connected through a USB port. “We believe that if this technology takes off, the next generation of laptops would include a photodiode receiver,” Nguyen said.
The idea for the system developed during conversations between Nguyen and colleague Alan Wang, assistant professor of electrical and computer engineering, who is collaborating on the project. Nguyen’s and Wang’s graduate students were able to build the first prototype in just eight months and the group has secured a provisional patent and has published paper in the 17th ACM International Conference on Modeling, Analysis and Simulation of Wireless and Mobile Systems that was runner up for Best Short Paper Award.
“I wanted all of my student to contribute to this project, because I think it’s going to be big,” Nguyen said.
To turn the invention into a marketable product, Nguyen is interested in finding a company to work with him to further develop and license the technology.