View source for Bluetooth indoor location system

==System==
* Use beacons mounted on stationary objects within a room to allow user supplied devices to triangulate their rough position inside the room
* The users may share their location via various means.
** XMPP
*** complex
*** relies on external infrastructure eventually
*** robust against network topology traversals (NAT/Firewall)
** Multicast
*** simple
*** not robust when traversing NATs
* Useful for a conference hall or the like, where an area is large enough to prevent finding ones way or friends easily.

testing guest captcha

==Hardware==
===SOCs===
* [http://www.mouser.com/ProductDetail/Nordic-Semiconductor/nRF51822-QFAB-R7/?qs=sGAEpiMZZMvQqVCO1QUke9rOCiF3q8UDR59ukwBL9d8%3d Nordic]
* [http://www.mouser.com/ProductDetail/Texas-Instruments/CC2540F128RHAR/?qs=sGAEpiMZZMuReUCzg6bfTFMX9eNsg5flb%2fyNLpDtSPE%3d TI]

===Front End/BT modules===
* just as expensive as SOCs

==Software==
===Phone App===
====Android====
====iThing====

===Firmware===
* bit-bang BTLE library [https://dmitry.gr/index.php?r=05.Projects&proj=11.%20Bluetooth%20LE%20fakery code] for reference

====Beacon====
* Similar use cases
** Beacon tagging - tags beacon to allow device to find the tagged item
*** [http://en.wikipedia.org/wiki/IBeacon iBeacon] - proprietary implementation
* Use [http://en.wikipedia.org/wiki/Bluetooth_low_energy#Proximity_sensing Proximity Sensing] Profile (PXP/FMP) to let user devices know where and roughly how far they are from the beacons.