Having your phone know where you are and what you're doing
is one of the creepiest (but most
useful) aspects of modern smartphones.
From Google Now to location-based notifications on iOS, you probably
take advantage of it every single day.
But we're still
using 1970s technology to make that happen, and when the tech finally
catches up with the 21st century, it'll change how you use your phone,
for the better. Mostly.
At the moment, your phone uses
two main methods to work out where you are – the Global Positioning
System (GPS) and Wi-Fi. GPS, as you're probably aware, is a system that
uses a global network of satellites to work out where you are.
The status quo
There's
a constellation of 24 American military satellites (up until 2000, the
rest of us couldn't really use it) that are spread out around the entire
world. When your phone wants to know where it precisely is, it tries to
acquire the signal beamed out by at least four of the satellites. It
then decodes that using some fancy maths invented by Einstein, and can
thereby work out where it is in the world, down to an accuracy of around
5 meters.
It's an incredibly clever system, and
absolutely perfect for applications like sat-nav. But for smartphones,
GPS actually kinda sucks. It's hugely battery-intensive to have on all
the time, clouds or slightly-too-high buildings can foil it, and it
doesn't work indoors.
To
try and get around this problem your phone uses an alternative system:
Wi-Fi location. Thanks to a couple of vast databases that
cross-reference Wi-Fi network data with geographical location, your
smartphone can normally work out where you are in the world in under a
second. It does so by looking at what Wi-Fi networks you can see, and
cross-referencing the network names with where they are on a map.
The
data for these databases is collected either through "wardriving" (cars
with Wi-Fi antennas driving around, collecting the data) or, more
commonly, by using every smartphone on a given platform. So, when you
have GPS and Wi-Fi switched on, it's quite possibly gathering data about
nearby Wi-Fi hotspots and phoning it home.
It's far less
accurate, but because it's using a fairly low-power sensor (the phone's
Wi-Fi chip) rather than trying to communicate with satellites in outer
space, it's a good option when you only need to know roughly where you
are.
Of course, there's one other, even less accurate
location-finding method that your phone can use: cellular triangulation,
which is the thing referenced in early episodes of 24, with Jack Bauer
hunched over a laptop trying to track the baddies.
Cellular
triangulation can work out where you are to within a couple hundred
metres (or, sometimes, a couple hundred kilometres) by looking at which
cell towers your phone is communicating with, and basically putting you
in the rough nearby area. It's not a particularly useful tool (unless
you're Jack Bauer), but it is somewhat handy for determining initial
location, before GPS gets on with the job.
The space race
The
most immediate and subtle change to location technology that you'll
probably see is the switch away from GPS, towards other satellite-based
systems. GLONASS (Global Navigation Satellite System) is the Russian
version of GPS, and it too uses 24 satellites to give global coverage.
It
doesn't really offer any advantages over GPS in and of itself, but
having access to two systems doubles your chances of getting a signal
quickly.
Which explains why Apple's included a GLONASS
chip in every iPhone since the 4S, and most Android manufacturers have
followed suit. (Well, that, and the fact that Russia has a 25% import
tax on any non-GLONASS-enabled handsets these days, so most
manufacturers find it worthwhile to stick the extra chip in.)
Europe's
challenge to GPS dominance is a system named Galileo. It works on
exactly the same principle as GPS and GLONASS, a bunch of satellites
orbiting Earth, but offers a few advantages. It has much better accuracy
with altitude, and a function that'll turn your phone into a rescue
beacon that can summon Mountain Rescue or the Coast Guard with the push
of a button, even if you're out of mobile phone reception.
Unfortunately, since Galileo is an EU project, it's running quite a long
way behind schedule and over budget, and isn't quite reality yet.
It's not all about the astronauts
But
even with this new host of satellite systems on the market, your phone
still can't accurately work out where you are indoors. That's a problem,
because indoor location services would open up a whole host of
possibilities. When you're out shopping, you'd be able to navigate round
a giant supermarket to find things or the Tescos app could give you a
route, based on your shopping list, to get in and out as fast as
possible.
Or, when you're at home, smart thermostats and
lighting systems could use your phone's location to work out where you
are in the house, adjusting lighting and temperature accordingly. The
possibilities are huge, and just like with most new tech, it's
impossible to predict what developers will do with it. After all, no-one
would've predicted that opening the iPhone up to apps would lead, seven
years later, to the existence of Flappy Bird.
A magnet and a seismometer walk into a bar…
Thankfully,
a bunch of clever start-ups and established R&D labs are already
working on making indoor location technology work better, with a whole
laundry-list of different approaches.
One of the more
mature technologies for indoor location tracking is our good old friend,
Wi-Fi. With the installation of antennas around a shop (or anywhere
else, for that matter), a far more accurate Wi-Fi grid can be built up,
which allows phones to be tracked to an accuracy of around a metre.
That's good enough for most purposes, like finding items on shelves.
It's
also good enough for shops to be able to track customers in store,
which is what the technology is currently (and very quietly) used for. A
whole host of firms offer "in-store analytics" for retail chains, which
basically amounts to tracking unsuspecting customers' phones using
Wi-Fi, looking at the path they take around the store and what products
they pause over, and then feeds that information to the stores.
However,
far less sinister technologies also exist, and also require far less
hardware than Wi-Fi solutions, which require dozens of antennas for just
one building. IndoorAtlas is a US-based company that maps buildings
based on their 'magnetic fingerprint'.
Basically, they
use the fact that minor variations in steel structures give buildings a
unique magnetic field, which can be used to geo-locate a phone with
accuracy of a metre or two, without needing to install any new
transmitters.
Even better, most phones already have
magnetometers already installed, and they use very little battery power.
Once the initial mapping of a building has been done, there's little to
stop magnetic location becoming the new standard (unless we all choose
to live in mud huts, of course).
Another slightly quirky
location concept is the Open Positioning System, which wants to use
existing low-frequency sources of seismic noise, things like power
station turbines, for example, to triangulate location, without needing
an expensive satellite system and without being hindered in the
slightest by cities. The idea, developed by a Royal College of Arts
student, is still in beta testing at the moment.
With so
many different options, however, the most promising solution of all
could be some kind of hybrid. BAE Systems, a British engineering firm,
has a research project that uses a whole mix of electromagnetic signals
from TV broadcasts, to Wi-Fi and cell towers to work out your location.
The theory is that whie one single system might not offer universal
coverage or great accuracy, bundling them all together probably will.
AlterGeo
is a company that already uses this approach for positioning: it uses
Wi-Fi, WiMAX, GSM, LTE, IP addresses and network environment based
location algorithms to serve location requests. It's not hard to imagine
adding in magnetic and seismic data, in addition to the hundreds of
location satellites already floating overhead, to work out exactly where
you are, indoors or outdoors, with zero effort.
While
that might have privacy advocates running for the tinfoil and blackout
blinds, being able to work out your location should vastly improve our
smartphones in the future. The current generation of smartphones, like
the iPhone 5S and Moto X, put "contextual computing" at the forefront of your handset.
They
pride themselves on being able to offer relevant information, whether
that's the current weather, train times or football scores, and better
location information will drastically improve how well they can do that.
The end result? Prepare to be even more attached to your smartphone –
but don't worry if you lose the damn thing, you'll know exactly where to
find it.
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