Method of estimating the position of a user device using radio beacons and radio beacons adapted to facilitate the methods of the invention

Abstract

Disclosed is the estimation of the position of a user device using radio beacons which are operable at a plurality of transmit power levels. The radio beacons may transmit their position and current transmit power level. Estimates of distance between a user device and a radio beacon can take into account both received signal strength and the current transmit power level of the radio beacon. The position of the user device can be estimated taking into account whether a radio beacon can be detected at a given transmit power level. The transmit power level of the radio beacon may vary according to a cycle. The transmit power level of the radio beacon may be changed to facilitate positioning, for example in response to a signal from a user device. A radio beacon changes transmit power level in a cycle. The radio beacon can reduce transmit power level responsive to a signal. The radio beacon may be compatible with Bluetooth short range wireless connectivity standard core specification version 4.0.

1 . A method of estimating the position of a user device comprising a Bluetooth receiver, the method comprising: the user device detecting one or more Bluetooth beacons configured to transmit signals at any of a plurality of discrete transmit power levels, and a computer processing system comprising a processor calculating an estimate of the position of the user device taking into account transmit power data concerning the transmit power level of the one or more said Bluetooth beacons at the time when the respective Bluetooth beacon is detected and beacon position data concerning the position of the one or more said Bluetooth beacons. 
     
     
         2 . A method according to  claim 1 , wherein the beacon position data is received from the Bluetooth beacons. 
     
     
         3 . A method according to  claim 1 , wherein the transmit power data is received from the Bluetooth beacons. 
     
     
         4 . A method according to  claim 1 , wherein, in at least some circumstances, the method does not take into account any measure of the strength of the signals received from the one or more Bluetooth beacons beyond whether or not the Bluetooth beacons can be detected. 
     
     
         5 . A method according to  claim 1 , comprising taking into account that one or more Bluetooth beacons cannot be detected at a given point in time. 
     
     
         6 . A method according to  claim 1 , comprising taking into account that a Bluetooth beacon can be detected at a time when it is outputting signals at a first transmit power level and cannot be detected at a time when it is outputting signals at a second lower transmit power level. 
     
     
         7 . A method according to  claim 1 , wherein for some or all of the Bluetooth beacons, the respective Bluetooth beacon automatically switches between at least some of the plurality of discrete transmit power levels. 
     
     
         8 . A method according to  claim 1 , comprising the step of causing a Bluetooth beacon to change its transmit power level to facilitate the estimation of the position of the user device. 
     
     
         9 . A method according to  claim 8 , wherein the user device, or a positioning controller, is programmed to generate a signal to cause a Bluetooth beacon to reduce its transmit power from a first discrete transmit power level to a second lower discrete transmit power level. 
     
     
         10 . A method according to  claim 8 , wherein the transmit power level of the Bluetooth beacon is increased to obtain a stronger signal. 
     
     
         11 . A method according to  claim 8 , wherein the user device sends signals to the Bluetooth beacon to change its transmit power level directly or indirectly. 
     
     
         12 . A method according to  claim 1 , comprising receiving a measure of an environmental property which affects distance measurement with the radio signal received from the Bluetooth beacon. 
     
     
         13 . A method according to  claim 1 , wherein at least some of the Bluetooth beacons are Bluetooth beacons compatible with the Bluetooth short range wireless connectivity standard core specification version 4.0 or later. 
     
     
         14 . A Bluetooth beacon comprising a transmitter configured to transmit data using radio signals at any of a plurality of discrete transmit power levels, and a processing system including a computer processor, the processing system being programmed to change the transmit power level at which the transmitter transmits to facilitate estimation of the position of a user device. 
     
     
         15 . A Bluetooth beacon according to  claim 14 , wherein the Bluetooth beacon is configured to automatically switch between at least some of the plurality of discrete transmit power levels. 
     
     
         16 . A Bluetooth beacon according to  claim 15 , wherein the Bluetooth beacon changes between discrete transmit power levels in a cycle. 
     
     
         17 . A Bluetooth beacon according to  claim 14  wherein the Bluetooth beacon is configured to change the transmit power level at which it transmits responsive to a received signal from a user device which is receiving data from the Bluetooth beacon or a positioning controller. 
     
     
         18 . A Bluetooth beacon according to  claim 17 , wherein the Bluetooth beacon changes the transmit power level at which is transmits responsive to a received signal by reducing the transmit power level at which is transmits. 
     
     
         19 . A Bluetooth beacon according to  claim 14 , wherein the Bluetooth beacon transmits its position in its transmitted radio signal. 
     
     
         20 . A Bluetooth beacon according to  claim 14 , wherein the Bluetooth beacon transmits data concerning its current transmit power level in its transmitted radio signal. 
     
     
         21 . A Bluetooth beacon according to  claim 14 , wherein the Bluetooth beacon transmits data to facilitate accurate distance measurement. 
     
     
         22 . A Bluetooth beacon according to  claim 21  wherein the Bluetooth beacon comprises a sensor to measure a property of the environment around the Bluetooth beacon and is configured to transmit a measurement of that property in its transmitted radio signal. 
     
     
         23 . A Bluetooth beacon according to  claim 14 , wherein the Bluetooth beacon is compatible with the Bluetooth short range wireless connectivity standard core specification version 4.0 or later. 
     
     
         24 . A Bluetooth beacon according to  claim 14 , wherein the Bluetooth beacon is configured to detect Bluetooth beacons and to transmit data concerning detected Bluetooth beacons to a data collection device. 
     
     
         25 . A non-transitory computer readable medium storing a computer program which, when executed by the processor, causes the processor to estimate the position of the user device by the method of  claim 1 . 
     
     
         26 . A non-transitory computer readable medium storing a computer program which, when executed by the processor of the Bluetooth beacon, causes the Bluetooth beacon to function as a Bluetooth beacon according to  claim 14 .