The system created by King Abdullah University of Science and Technology is able to modulate the sunlight that passes through it, implanting polarity changes to encode data
The system, for now, can transmit data at a speed of 16 kilobits per second
(sustainabilityenvironment.com) – What if sunlight replaced current Wi-Fi technology? What if a “simple” window was enough to replace home routers? This possibility is being worked on by a group of scientists from King Abdullah University of Science and Technology (KAUST), Saudi Arabia. The researchers have created a “smart glass” that can polarize sunlight and offer a low-energy alternative to traditional Wi-Fi.
A luminous path for wireless communications
A luminous path for wireless communications
The manipulation of LED lights as a communication tool has garnered considerable attention in recent years. The vast majority of work in this field focuses on the modulation of light intensity but a second pathway that employs the direction of polarization as a vector of information is also slowly making its way. Changes in intensity or polarity can have the same function as 1 and 0 in the binary code; and just the camera of a smartphone to detect and decode them. But if the former can also be perceived by the human eye (and not be too pleasant), the latter are practically invisible.
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It is exactly at this level that Saudi research fits in but with a big and fundamental difference: the light used is not artificial but natural. Professor Basem Shihada, head of the group, explains how the idea came about. “I was just hoping to use a cell phone camera to record an encoded stream of light, try to decode the video and retrieve the data; that’s when I thought, ‘Why not do the same with sunlight? It would be much easier’. So we started exploring sunlight as a carrier of information“.
Liquid crystals and sunlight for KAUST smart glass
To take advantage of the sun, the team designed a two-part communication system. “There is a light modulator that can be incorporated into a glass surface and a receiver in the room,” explains researcher Osama Amin. “The modulator is an array of our smart glass elements known as Dual-cell Liquid Crystal Shutters (DLS)”. The matrix of the liquid crystal shutter acts as a filter to encode the signals in the light that passes through the glass. To operate it requires only 1 watt of power, where traditional Wi-Fi routers use between 5 and 20 watts. Calculations indicate that in its current form the smart Glass could transmit data at a speed of 16 kilobits per second, but scientists obviously want to increase capacity. “We are now ordering the necessary hardware for the implementation of a test bench prototype,” said Professor Shihada. “We would like to increase the speed of data from kilobits to mega and gigabits per second“.
