Google Confirms Barometer Intent: Faster GPS Locks
Yesterday we dove-in to the new sensor coming to the Samsung Galaxy Nexus, its barometer. Though there’s been one on the Motorola Xoom tablet since its release, the sensor will be new to Android smartphones. We speculated about all sorts of ways we might get some use out of it, but now we have some answers straight from the horse’s mouth, with Android compatibility chief Dan Morgill addressing the barometer on his Google+ page.
According to Morgill, the intended use for the barometer sensor will be speeding-up GPS acquisition. We had mentioned the ability to gauge altitude via barometric pressure, but focused on its use in estimating altitude independently of GPS, saving battery life. Instead, Morgill says, it’s to make initial GPS calculations go faster.
While it’s easy to keep-up with GPS satellites, an initial lock-on can take a smartphone’s GPS receiver a little while to make. Besides needing to wait to receive satellite constellation data from the GPS birds, the receiver needs to solve a complicated set of equations to figure out your location. One of those values it’s solving for is your altitude coordinate, and if you already have a pretty good guess what it’s near, you can speed up the rest of the equation-solving. Of course, you always could use the sensor for any of the uses we mentioned, given the proper app support, but this GPS-assist looks to be the primary motivation for the sensor’s inclusion.