Researchers have discovered a cost-effective, low-energy method that allows numerous devices—like industrial machines and laboratory equipment—to seamlessly exchange data by utilizing previously unused high-frequency signals. This innovation is an upgraded form of a device that facilitates wireless data transmission, often referred to as a tag.
Researchers have discovered a cost-effective, low-energy method that allows numerous devices—like industrial machines and laboratory equipment—to seamlessly exchange data by utilizing previously unused high-frequency signals.
This new technology could quickly make real-time monitoring inexpensive and efficient in industrial environments. For example, it could track the status of manufacturing robots or identify gas leaks in refineries without the need for energy-intensive signal transmitters. The researchers indicated that with some engineering advancements, this technology could be utilized in extensive applications such as smart cities and farming.
Essentially, this technology is an enhanced version of a tag used in wireless communication systems. The new tag can enable data transmission across a vast network of devices using a technique known as backscattering. This process involves a central reader sending a signal to a sensor tag to collect information, after which the tag reflects the ambient signal directly back to the reader. While backscattering is already employed in simple systems like contactless payment and building entry cards, it has only been feasible at low frequencies until now.
The limitation of low frequencies creates issues when many devices attempt to communicate simultaneously. The introduction of additional signals increases the chances of them interfering with one another and becoming muddled. Moreover, traditional backscatter systems often experience slow communication speeds, as lower frequency signals restrict the volume of data that can be transmitted back and forth at once.
Developed by researchers from Princeton, Rice University, and Brown University, the new tag is a pioneering advancement that employs backscattering in the sub-terahertz range, which falls under a high-frequency segment of the radio spectrum. This range supports fast data transmission across wide bandwidths. As a result, it may become feasible to enable signal transmission for dense networks of devices using passive tags, significantly conserving power and reducing infrastructure needs compared to conventional wireless systems.
“I strongly believe this technology will be applicable in a variety of fascinating contexts,” stated Yasaman Ghasempour, an assistant professor of electrical and computer engineering at Princeton and the principal investigator of the study. “Contrary to conventional thinking, this research demonstrates that low-power, scalable communication is achievable in the sub-terahertz range.”
The findings were published on Oct. 9 in Nature Communications.
Utilizing backscattering at elevated frequencies presents challenges, as the signals tend to fade as they travel and require high precision to cover long distances. “The reader must create a narrow, focused beam directed at the tag’s exact location, and the low-power tag must replicate this without consuming energy. That’s where the challenge lies,” explained Ghasempour.
Conventional backscatter tags send signals back to their source using basic antennas that typically emit energy in all directions, leading to a minimal amount of that energy reaching the reader. Although some sophisticated tags are capable of directing their signals, their ability is limited, and they are confined to a narrow frequency range. Ghasempour noted that realizing sub-terahertz backscattering necessitated a complete rethinking of the tag’s design. “Using an outdated hardware approach and simply scaling it up would not suffice,” she remarked.
To overcome these limitations, the researchers developed an entirely new antenna design. These innovative antennas enable the signal direction to adjust automatically based on frequency variations. This functionality allows the tag to guide the signal for prolonged communication ranges while minimizing interference from other signals. Essentially, each tag’s interference impact is constrained both spatially and spectrally.
Ghasempour expressed hopes that others will study this paper and enhance the technology for advanced applications. If a method to amplify signals in the system at low costs can be devised, this technology could facilitate sensor networks throughout cities to monitor air quality or vehicular flow.
Tags could also be affixed to traffic signs for detection by autonomous vehicles, allowing them to communicate directives like “stop” or “yield,” even in circumstances where visibility is compromised by fog or snow. In agriculture, this technology might enable extensive networks of soil sensors within fields or forests, delivering real-time insights into moisture levels or temperature.
According to Ghasempour, the development of low-power data modulators within these systems is an exciting field of research, and this innovation is an important step toward reducing costs and power usage across the entire wireless infrastructure.
