This has happened to anyone with a cell phone; calls were lost or dropped because the service was suddenly unavailable. Or worse, the location pin ends up in a navigation app. Researchers at UBC Okanagan are looking for ways to improve cell phone communication and geolocation capabilities by investigating “smart” surfaces that can send signals from the tower to customers to improve communications. A smart surface involves placing clear reflective elements on windows or panels in buildings in a dense urban environment.

Dr. Anas Chaaban says the goal is to improve wireless service for millions of Canadians. She said there are currently more than 12,000 wireless antenna towers. Still, the lack of cellular communication is a common problem.

An associate professor in UBC’s Okanagan School of Engineering, Dr. “The increasing use of mobile technology worldwide requires research that uncovers potential new approaches within our existing infrastructure,” says Chaaban. Despite cell towers being placed on the roofs of major cities and handling the data and phone traffic of millions of Canadians every day, gaps in service still remain.

Dr. Chaaban and his team at UBCO’s Communication Theory Lab have developed transmission schemes that will include reconfigurable smart surfaces (smart surfaces) to act as reflectors in existing wireless networks in urban centers.

A reconfigurable smart surface (RIS) is a panel of many individual reflective elements, each of which can manipulate the input signal and reflect it. This change can be controlled by an electrical signal that allows the RIS to improve communication or generate signals useful for locating users on the network.

To improve accuracy, the researchers developed a new localization system in which RIS can operate as a satellite. By making the surface smart, it can transmit signals to cell phones, which can then use those signals to generate an accurate location estimate, he says. Accurate location estimation is useful not only for location services, but also for improving tower-to-phone transmission with optimized location-aware transmission schemes using RIS.

“Users never expect a call to drop, and they also expect lightning-fast data rates,” he says. “But to achieve this goal, networks need to be constantly updated.”

The researchers tested their theory using multiple modular RISs that allow simultaneous localization of multiple users with low complexity for each RIS. They also developed and tested RIS-enabled transmission schemes that outperform existing schemes.

“We simulated the proposed localization protocol and demonstrated its effectiveness using an urban microcell street canyon scenario,” he explains. “The protocol works for several users at the same time. You can exchange data, find users and enjoy a reliable connection even in areas with intermittent service.”