Instead of phones becoming more multifunctional and replacing laptops, new computers at CES 2018 are embracing the best phone features.
Everyone seems to be insisting on installing cameras all over their homes these days, which seems incongruous with the ongoing privacy crisis — but that’s a post for another time. Today, we’re talking about enabling those cameras to send high-definition video signals wirelessly without killing their little batteries. A new technique makes beaming video out more than 99 percent more efficient, possibly making batteries unnecessary altogether. Cameras found in smart homes or wearables need to transmit HD video, but it takes a lot of power to process that video and then transmit the encoded data over wi-fi. Small devices leave little room for batteries, and they’ll have to be recharged frequently if they’re constantly streaming. Who’s got time for that? The idea behind this new system, created by a University of Washington team led by prolific researcher Shyam Gollakota, isn’t fundamentally different from some others that are out there right now. Devices with low data rates, like a digital thermometer or motion sensor, can something called backscatter to send a low-power signal consisting of a couple bytes. Backscatter is a way of sending a signal that requires very little power, because what’s actually transmitting the power is not the device that’s transmitting the data . A signal is sent out from one source, say a router or phone, and another antenna essentially reflects that signal, but modifies it. By having it blink on and off you could indicate 1s and 0s, for instance. UW’s system attaches the camera’s output directly to the output of the antenna, so the brightness of a pixel directly correlates to the length of the signal reflected. A short pulse means a dark pixel, a longer one is lighter, and the longest length indicates white. Some clever manipulation of the video data by the team reduced the number of pulses necessary to send a full video frame, from sharing some data between pixels to using a “zigzag” scan (left to right, then right to left) scan pattern. To get color, each pixel needs to have its color channels sent in succession, but this too can be optimized.