Indoor location is expected to change the marketplace radically and we heard a lot about it during
Location Business Summit 2012 from both platform players like Google and vendors providing solutions to achieve indoor positioning.
Steve Gray, CTO from
CSR presented a nice overview of the technical alternatives for indoor positioning. He presented two major solutions, wifi and cellular signal footprinting and
pedestrian dead reckoning.
For the signal fingerprinting method, one option is to use an enterprise class wifi and positioning center from vendors like
Cisco, which uses angle of arrival, time of arrival or signal strength etc to calculate position. A cheaper alternative is given as using the existing wifi and cellular signals in the environment. After fingerprinting the environment, position is determined by interpolating the finger print data from database. After the initial finger printing, database is fed with the data from users to allow the system to adapt to the radio changes in the environment.
Apple’s blockage on the
RSSI API preventing the applications to see the wifi signal strength level around is given as the major blocking issue for this method. Most consider that Apple is saving it for themselves for their own indoor positioning solution.
Many criticized
Google about their indoor positioning quality saying that their data is based on the cars driving around the buildings which is not good for deep buildings like malls and airports. It looked like most (except Google) ignore
Google’sMap Floor Plan Marker, which enables Google to have the indoor radio fingerprint by volunteered users. Someone mentioned that Google is also biking indoors too.
Sensewhere says fingerprinting is expensive and labor-intensive while sensor-based positioning can impact the power consumption radically. They say their “
dynamic crowd sourcing” system is the solution which is completely fed by the people walking in the building with no need of initial fingerprinting of the building. Though they did not provide any technical details, they were so confident about their solution.
CSR talked about
PDR which is using kinematics to estimate indoor positioning as an alternative solution to the problem. It is said that micro-electro-mechanical systems (MEMS) made it possible to determine accelaration and velocity of device. The problem with this method is the error accumulating over time / steps, introducing the need of synchronization with some known source / location from time to time.
CSR also mentioned about the recent BlueTooth v4 protocol, which can push some information (like coupon) to the phone or wake up an application. They say this interface is supported by most of the upcoming phones, including recent ones like iPhone 4s.
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