There is a bluetooth device out of sight in a room that is paired to my Android smartphone, and I can connect to it when I am close by. (It is a muted audio device.) Are there any methods to locate that device within the room with the use of the smartphone? Say, by dynamically measuring signal strength so that I can move the device around to see where it gets stronger.
Both App downloads, Android Studio( with Java), and other sorts of answers are welcome. (But AS is more appreciated.)
Not really, with a standard Bluetooth device and antenna, there's a lot of really big technical problems, and even physics is against you
You may or may not be aware of BLE and Bluetooth Beacons - there is a BLE Specification called Proximity that allows small bits of data to be sent as Bluetooth Advertisements. Devices can be calibrated and made to interpret these and the RSSIs etc and give a fairly reliable (depends) proximity
There are lots of libraries out there for working with them- and apps. I suggest taking a look at Radius Networks' Altbeacon library, it does all the maths and device specific calibrations that you would otherwise have to do yourself. All the big Beacon Manufacturers have their own though (Kontakt.io, Estimote etc)
Be aware, unless you have a directional mic, BLE should not be considered directional without using some kind of triangulation technique (otherwise you can just say "I am X meters from the device" without knowing if that was up, or behind or whatever)
Also be aware, it's incredibly open to being confounded by other sources of EMF and materials that absorb your waves.
Even more be aware, Smartphone BT Adapters vary wildly, they all log differently, have different nuances and react differently in different situations, but typically it's really good. Some devices like the Nexus 4 should not be used for BT, some hardware kink means the WiFi and BT don't effectively share the Antenna well enough and conflict (also I think the form factor just interferes too)
The best way to position a person or object in a room is by using a mixture of processed and aggregated readings from the device sensors and perhaps even some other hardware in the room. If you look at Google Maps, it doesn't wholly rely on GPS, just like indoor navigation using BLE Beacons shouldn't wholly rely on Bluetooth. Beacons just apply context,
Source: Microlocation developer
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