HitchHike sees Stanford engineers take low power IoT to new level
hitchhike , a new low-power technology developed by Stanford engineers
The HitchHike concept: HitchHike enables backscatter communication between commodity 802.11b WiFi radios

HitchHike sees Stanford engineers take low power IoT to new level

They’re calling it ‘the missing link’ of the Internet of Things. This is HitchHike, the first self-sufficient WiFi system to enable the transmission of data using just microwatts of energy. 

While many futurists have predicted a world not far from now in which every device – across industry, smart cities and consumer technology – taps into and communicates via an interconnected Internet of Things, putting that vision in place is easier said than done.

To bring about this connected, automated future, IoT developers and engineers are going to need to find a way to power it all. Low-power solutions such as LPWA are making headway and working towards solving the problem, and now a group of Stanford engineers have taken the concept one step further.

The team at Stanford was led by Sachin Katti, an associate professor of electrical engineering and computer science, and Pengyu Zhang, a postdoctoral researcher. The group has developed HitchHike, a tiny, ultra-low-energy wireless radio system.

The video below features an off-the-shelf Intel WiFi transmitter ( the black box on right) and an Apple MacBook Pro on the left, acting as the WiFi receiver. In the middle is a prototype of the HitchHike device. It’s connected to a heart rate sensor. HitchHike samples the heart rate data and piggybacks it on the WiFi signal from the Intel WiFi router. The Apple laptop receives, extracts and displays the piggybacked signal in real-time.

Read more: Sierra Wireless announces LPWA solutions for global IoT market

“HitchHike is the first self-sufficient WiFi system that enables data transmission using just microwatts of energy – almost zero,” Zhang said. “Better yet, it can be used as-is with existing WiFi without modification or additional equipment. You can use it right now with a cell phone and your off-the-shelf WiFi router.”

Hitchhike could boost the adoption of IoT technology

According to a research paper presented at the Association for Computing Machinery’s SenSys Conference, HitchHike technology is so low-power that it could be driven for a decade or more by a tiny battery. Devices could even harness energy from radio waves to power themselves indefinitely.

The team’s HitchHike transmitters have a range of up to 50 metres and can transmit around 300 kilobits of date per second.

“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 WiFi. The technology could potentially even operate without batteries. That would be a big development in this field.”


The Stanford team’s technology has been named ‘HitchHike’ because it essentially jumps on board incoming radio waves, translates incoming signals and retransmits its own data on a different WiFi channel. So HitchHike projects WiFi signals out with a slightly different message to when they came in, a type of signal called backscatter.

Read more: IoTUK seeks partners for UK LPWAN and experimentation testbeds

To send out a meaningful message and communicate with other devices, the HitchHike team has developed a system they call Codeword Translation.

“HitchHike opens the doors for widespread deployment of low-power WiFi communication using widely available WiFi infrastructure and, for the first time, truly empower the Internet of Things,” Zhang said.