Indoor Positioning System for Windows Phone 7

Question

I am looking at options for implementing Indoor Positioning System in a Windows Phone 7 app. This app is going to be used to guide users inside shopping malls, so location accuracy up to a few meters is very important. I googled a bit and came across Redpin - http://redpin.org which looks good but they don't have a ready client for Windows Phone 7 yet. Redpin only supports iOS and Android as of now.

Can anyone here help with this? Has anybody here implemented Indoor Positioning System on Windows Phone 7 app?

Answer 1

Windows Phone 7 does not provide enough information to be able to produce such a system without a very specific WiFi infrastructure.

To implement such a solution you would need to be able to access information about connected (or available) WiFi networks or access points and the signal strength of each. From these you could triangulate an approximate location.

However,
As the WP7 SDK does not provide information on an access point name or signal strength this becomes very difficult.

The only ways round this would be to identify a location by network name, assuming that each access point used a different name, so as to provide greater accuracy.
Or you had a proxy on the access points that could add additional location information to the request, so as to provide a greater level of accuracy without needing to create lots of uniquely named networks.
Either way would be a hack and be unlikely to produce the level of accuracy needed for your requirements. Unless you know you have the number of users with appropriate devices to justify creating such a system on WP7 at the moment I'd advise against this for now and hope that additional, required, functionality becomes available in a future version of the platform.

Answer 2

Here is a list of indoor positioning API providers. Most options are for Android, but this would be a good place to start to see if anything has recently become available for WP7: https://bitly.com/indoornavigation

Answer 3

Many of these systems use a "finger printing" technology... meaning what happens is a person needs to make a recording of the indoor space radio environment. That recording is then overlayed on the map to get the spaces unique radio fingerprint. In theory it would work great (and it does) the problem is however the signals change. The more users on any of the signal streams and the load will change the signal level or integrity.

If the signal changes more then 20% (in most cases) the recording needs to be redone. Depending on the size of the space that may be a very time intensive process.

The other problem is about 6 months ago apple took the ability away to read the rssi values seen on the phone... with out that reading the finger printing tech will not work on an apple device. That's why most of these API's are all android only... RedPin I don't think has updated their site to reflect that..

Answer 4

you can simply use RFID like NFC on windows phone:

http://rfidroundup.blogspot.com/2011/04/microsoft-to-bring-nfc-to-windows-phone.html

Or

if you can't wait for this OS version, you can use an Sound-Frequency indicator using build in Microphone. Peep sender and fourier analysis of noise detection. http://msdn.microsoft.com/en-us/library/ff431744%28v=vs.92%29.aspx

For more concept details, you need to share some details with me.