The Internet of Things push is real, and a newly developed ultra-low-power Wi-Fi radio developed by Standford researchers might just put a little more oomph behind the proliferation of connected devices.
Already in the wireless world, the IoT is taking over. U.S. wireless carrier AT&T already has more than 30 million connected devices on its network and rival Verizon has increased its IoT revenues to more than $200 million. By 2020, Gartner has forecasted more than 20.8 billion connected devices will be in use worldwide.
But while the IoT has been growing rapidly, limitations for devices still exist in two main areas: connectivity and battery life. Or at least, they did exist.
In a paper presented at the November Association for Computing Machinery’s SenSys Conference, Stanford researchers unveiled a new ultra-low-power Wi-Fi radio – dubbed HitchHike – that piggybacks on ambient radio waves to transmit packets. The system also has the potential to glean electromagnetic energy from surrounding radio waves to power itself, researchers said.
According to the researchers, led by Associate Professor of Electrical Engineering and Computer Science Sachin Katti and Postdoctoral Researcher Pengyu Zhang, HitchHike is a “low power backscatter system that can be deployed entirely using commodity Wi-Fi infrastructure.” Unlike traditional backscatter systems, Katti and Zhang said HitchHike eliminates the need for specialized hardware to generate radio signals, instead using commodity Wi-Fi radios as both a radio signal source and receiver for decoding backscattered signals.
The system works by reflecting existing Wi-Fi transmissions and, using a new technique called “codeword translation,” embeds its own information on the standard packets. Codeword translation simply involves trading the originally transmitted 802.11b codeword for another valid codeword, the researchers said.
Experiments have shown HitchHike can hit throughput speeds of up to 300 kbps at a range of up to 34 meters and 200 kbps at a range of up to 54 meters, the researchers noted.
Zhang observed the HitchHike system uses only micro-watts of energy, allowing it to run on a coin-sized battery for potentially more than a decade.
“HitchHike could lead to widespread adoption in the Internet of Things,” Katti said. “Sensors could be deployed anywhere we can put a coin battery that has existing Wi-Fi. The technology could potentially even operate without batteries. That would be a big development in this field.”
According to researchers the HitchHike system could become available for incorporation in connected devices within three to five years.