Admittedly this falls under the category of first-world problems, but wearable devices have a short battery life that in large part is due to the connectivity drain. It doesn’t matter whether that connection is via Bluetooth LE, Wi-Fi or, occasionally, GSM (Global System for Mobile Communications) — if you could scale back or reduce the power used while transmitting and receiving information, the wearable would have a longer battery life. It is practically a law of the universe, or at least mechanical engineering.
In truth, there are a lot of other related factors that drain a wearable's battery, but today we are looking at the solutions researchers are developing to address this particular problem.
For they are.
Why? Well, in the case of NASA, this research could allow astronauts to transmit images from space using less power — a scenario that clearly is more dire than having one's Fitbit run out of juice during a run.
For everyone else, though, it comes down to first-world numbers: As in, by 2020, the wearable market will be worth $80 billion, according to Juniper Research. As in, 76% of Americans plan to purchase a wearable device in the next six to 12 months, and longer battery life is a key feature they will be looking for, according to TE Conectivity.
So, yes, research is under way tackling this problem from many different angles.
A microchip that reflects wireless signals
NASA's Jet Propulsion Laboratory and the University of California at Los Angeles are collaborating on this issue. The project is headed up by Adrian Tang of NASA and UCLA's M.C. Frank Chang. Their approach is to develop a wireless silicon microchip for wearable devices that can transmit data by reflecting wireless signals instead of using regular transmitters and receivers.
It is the external transmitter that is expending energy instead.
The chip is also able to sense and suppress background reflections and winnow other objects in the room that are also sending signals, like the walls, floors and ceilings.
This allows the Wi-Fi signal to be transmitted without interference.
The chip transmits information up to three times faster than regular Wi-Fi, the researchers say. Specifically, at about 8 feet, the data transfer rate is 330 megabits per second — using thousand times less power than a regular Wi-Fi link.
There's still work to be done though; as the researchers noted, you still need a base station and Wi-Fi service for this to work — and they both must be powerful, or at least plugged in, to support the wearable's light footprint.
Streaming storage to a nearby phone
A Microsoft research project, called WearDrive, has developed a technique in which the wearable's storage operations — which are highly energy-intensive — are offloaded to the smartphone to which it is tethered using a Wi-Fi or Bluetooth connection.
WearDrive's researchers just presented a paper outlining the methodology at the USENIX Annual Technical Conference, where it was named one of the three best papers.
The wearable only does smaller, less energy-intensive tasks, giving it a better battery life.
Chipmakers look at the problem
Chipmakers, too, are working to address the problem — although, obviously, their solutions don’t have the imagination or panache that say, NASA's does.
Earlier this year Broadcom introduced a smartwatch reference design platform for wristband-style wearables and higher-end smartwatches that it billed as significantly lowering the power.
Broadcom did it by shrinking the circuit board size by about 40% and offloading some tasks from the applications processor on to less power-intensive parts of the system.
The chipmaker says the power consumption difference is significant: In a first-generation wearable, playing back an MP3 file would consume about 24 milliamps of juice. Using Broadcom's reference design, the wearable can do the same task at 15 milliamps, at close to double the music playback time.
More recently Rockchip, the semiconductor company in Fuzhou, China, released its own version of a low-power Wi-Fi chip.
Its design, the company says, significantly reduces power consumers of IoT smart devices by 85% — enough to power the same set of AAA batteries for 35 years.
And because the Rockchip RKi6000 uses so little energy, it can fit in small batteries — and conversely smaller wearables. However, based on its statements, the chipmaker appears to be targeting the chip for cameras, smart plugs, access controls and home appliances.