Using super low power devices, researchers from the University of Washington just broke a long-held distance record by wirelessly transmitting data up to 1.74 miles (2.8 km)! Their latest version uses 1,000 times LESS power than other current technologies reaching this distance.

Perhaps the people happiest about this breakthrough are those invested in small sensor technologies used in the medical, agricultural, military, wearable consumer tech, and other industries. This basically means sensors can be made smaller and cheaper without batteries and people won’t have to carry a receiver so close to collect data but can instead monitor many more devices remotely.

The UW team’s long-range backscatter system uses reflected radio signals to send data at extremely low power and low cost. They successfully transmitted signals throughout a 4,800-square-foot house, a 41-room office area, and a one-acre vegetable farm. The system is detailed in a paper to be presented Sept. 13 at UbiComp 2017.

“Until now, devices that can communicate over long distances have consumed a lot of power. The tradeoff in a low-power device that consumes microwatts of power is that its communication range is short,” said Shyam Gollakota, lead faculty and associate professor in the Paul G. Allen School of Computer Science & Engineering. “Now we’ve shown that we can offer both, which will be pretty game-changing for a lot of different industries and applications.”

The advantage of reflected (“backscattered”) radio signals is the sensors need almost no power and can get it through thin cheap, flexible printed batteries or ambient sources. The disadvantage is the receiver’s difficulty distinguishing the extremely weak reflections from the original signal and other noise.

The system has three components:
1. a source that emits a radio signal,
2. sensors that encode information in reflections of that signal
3. and an inexpensive off-the-shelf receiver that decodes the information.

“It’s like trying to listen to a conversation happening on the other side of a thick wall — you might hear some faint voices but you can’t quite make out the words,” said Mehrdad Hessar, an Allen School doctoral student. “With our new technology, we can essentially decode those words even when the conversation itself is hard to hear.”

These young electrical engineers exemplify the entrepreneurial spirit. Instead of trying to solve a problem from within its paradigm, they started from scratch and came up with a breakthrough solution. They created a business around their invention called Jeeva Wireless that will sell product next year.

These high-tech transmitters provide the tools to embed micro monitors in countless everyday objects. As with all advancements of technology, we must be cautious of the effects to our innate rights. With smaller and smaller sensors communicating data across vaster distances in their own encrypted language, our privacy may be at risk.