The future of cellular data may lie in “bending” light beams through the air to power 6G wireless networks at incredibly high speeds, eliminating the need for line-of-sight between transmitter and receiver. In a new study published March 30 in the journal Nature’s Communications Engineering, researchers describe how they developed a transmitter that can dynamically tune the waves needed to support future 6G signals.

The most advanced cellular communications standard is 5G. 6G is expected to be thousands of times faster and available by 2030, according to trade body GSMA. Unlike 5G, which operates mostly in the sub-6 gigahertz (GHz) bands of the electromagnetic spectrum, 6G is expected to operate in the sub-terahertz (THz) range between 100 GHz and 300 GHz, with THz bands just below infrared. The closer this radiation is to visible light, the more strongly the signals are blocked by physical objects. The main problem with high-frequency 5G and future 6G is that signals need a line of sight between transmitter and receiver.

But in experiments, scientists have shown that you can effectively “bend” high-frequency signals around obstacles such as buildings.

“This is the world’s first curved data channel and a major milestone in realizing 6G’s vision of high data speeds and high reliability,” said Edward Knightley, co-author of the study and professor of electrical and computer engineering at Rice University.

Photons, or particles of light, that make up THz radiation in this region of the electromagnetic spectrum generally travel in straight lines unless space and time are distorted by the massive gravitational forces exerted by black holes. But researchers have found that self-accelerating light beams, first demonstrated in a 2007 study, create special configurations of electromagnetic waves that can bend or twist to one side as they travel through space.

By designing transmitters with patterns that vary the strength, intensity and timing of signals carrying data, the researchers created waves that work together to create a signal that remains intact even when its path to the receiver is partially blocked. They discovered that by mixing data in an unobstructed pattern, it was possible to create a beam of light that adapts to any object in its path. So while the photons are still traveling in a straight line, the THz signal is actually bending around the object.

We’re getting closer to the future of 6G

Although bending light without the power of a black hole is not a new research, what is important about this research is that it can turn 6G networks into a practical reality.

Millimeter wave (mmWave) 5G currently offers the fastest network bandwidth, occupying the higher 5G radio frequencies of the electromagnetic spectrum from 24 GHz to 100 GHz to deliver theoretical maximum download speeds of 10 to 50 gigabits (billion bits) per second. THz beams are above mmWave between 100 GHz and 10,000 GHz (10 THz); This is necessary to deliver data speeds of one terabit per second, which is almost 5,000 times the average 5G speed in the US.

“We want more data per second,” said Daniel Mittleman, a professor at the Brown School of Engineering. “If you want to do this, you need more bandwidth, and that bandwidth is not available using traditional frequency bands.”

However, due to the high frequencies at which they operate, 5G mmWave and future 6G signals require a line of sight between the transmitter and receiver. But thanks to practical signal transmission along a curved path, future 6G networks will not need buildings covered with receivers and transmitters.

However, for signal distortion to work, the receiver must be within the immediate field of the transmitter. Using high-frequency THz beams, this means a distance of approximately 33 feet (10 meters); This isn’t suitable for citywide 6G but could be practical for next-generation Wi-Fi networks.

“One of the big questions everyone asks us is how much you can bend and how far you can go,” Mittleman said. “We’ve made a rough estimate of these, but we haven’t quantified them yet, so we’re hoping to map them.”

While the degradation of THz signals is promising for future 6G networks, the use of THz spectrum is still in its infancy. Scientists said that thanks to this research, we are one step closer to realizing cellular wireless networks with unprecedented speed.