A tiny, bendable antenna capable of 5G and Wi-Fi connectivity has been developed by scientists, and rather than being made for phones or a smartwatch, it’s for smart clothing. The 2-port multiple-input-multiple-output (MIMO) antenna is integrated into a textile and has been designed for use close to the human body. It is small and low profile enough that it can be hidden in the pocket of a shirt. How small? The antenna is just 24 x 24mm.
The research states the antenna can be fabricated on different materials, including denim, cotton, felt, and even silk. The version tested was made using denim, can be flexed horizontally and vertically without an impact on performance, and has sufficient gain to make it powerful enough for normal use, while remaining safe for use right next to the body. Its ability to use dual-band Sub-6 5G and Wi-Fi frequencies — 3.5GHz 5G and 5.2GHz Wi-Fi — set it apart from other recent single-band wearable antennas, and others without MIMO connectivity. The paper explains why this is important:
“With the growth of 5G and 6G networks, the entire nature of communication will be based on MIMO antennas which provide reliable communication due to their low path losses, high channel capacities, high data rate, and increased communication range without extra input power requirements.”
Connected clothing has potential uses by the military and in space exploration, but more relevantly to us is the use in health and sport. The dual-band antenna means sensors inside clothing can collect and send health data without the need for a smartphone or smartwatch, reducing the need to carry additional devices and increasing versatility. Additionally, an antenna inside smart clothing could be used to add connectivity to other wearables, and pave the way for true smart clothing with integrated flexible screens.
Crucially the antenna’s Specific Absorption Rate (SAR) has also been assessed, which shows how much power is absorbed by the human body and whether it’s unsafe. The low-power nature means it falls well below the minimum acceptable levels, according to the research team, and is considered harmless. On the subject of power, the paper does not go into detail about how the antenna is powered, another essential piece of the puzzle to create smart clothing. While an exciting development, the antenna is still a research project and not set to be released for use inside clothing, but it’s a step in the right direction.
Connected clothing, or smart clothes, have yet to hit the mainstream. Perhaps the best known example is Google’s Project Jacquard and subsequent Levi’s Trucker and Sherpa denim jackets, and a connected backpack from Saint Laurent. Increasing functionality through the use of antennas may help bring more products to life in the future.
