New 3D-printed antenna can generate electrical energy from 5G alerts
Carriers are rolling out 5G networks around the world and promising to deliver lightning-fast data to devices of all shapes and sizes. So far, the speed figures from 5G were little more than smoke and mirrors. However, the architects of 5G technology may have inadvertently provided the key to the wireless power supply. A Georgia Tech team developed a small, 3D-printed antenna that can generate power from 5G waves. This technology has the potential to convert wireless data networks into a wireless power network.
5G comes in different flavors, each with their own advantages and disadvantages. There is low-band 5G that operates in the hundreds of megahertz range and offers good range at lower speeds. Mid-band signals on the order of a few gigahertz can provide much higher speeds in exchange for a slight reduction in range. Both are classified as sub-6 GHz; Once you get above 6 GHz, you are in the millimeter wave 5G range, which can go up to 40 GHz in the US. Verizon and AT&T started that because that spectrum was readily available and very, very fast. The problem? Very little range.
Some previous attempts to get power from wireless signals have focused on Wi-Fi, which, like mid-band 5G, is a few gigahertz, but millimeter waves (mmWave) is a whole different story. Millimeter waves (mmWave) 5G can transmit several gigabits per second due to their high frequency and power, which means that more energy is available for harvesting. This was also demonstrated, but these demos required a large rectifying antenna. The larger the antenna, the narrower its field of view, which makes it impractical for energy generation. The tiny maps developed by the Georgia Tech team solve this problem by adding a component called a Rotman Lens – the spiky shape in the center (above).
Rotman lenses are already widely used in 5G beamforming applications. You can reshape a single narrow beam into multiple simultaneous beams that cover a larger area. This is why the Georgia Tech antenna is so small and efficient – it uses 21 times more power than a standard rectified antenna of the same size.
However, we are still not talking about a large amount of power. The high-frequency mmWave signal generates around 6 microwatts of power at a distance of 180 meters from a 5G transmitter. That is also with unobstructed line of sight; mmWave signals are too high frequency to pass through walls, but that also makes them easier to use for wireless power.
A few microwatts are still enough to power sensors and simple IoT devices, so no batteries are required. The team believes that wireless power could become a transformative 5G technology. However, this is likely only true if carriers figure out how to charge for it.