Localization of a mobile device in distributed antenna communications system
View Patent ↗The present invention provides a method and apparatus for localization of a mobile device in a distributed antenna communications system. In accordance with an embodiment of the invention, a distributed antenna system includes a plurality of distributed antennas that are communicatively coupled to a hub. A mobile communications device to be located is communicatively coupled to the hub via one or more of the antennas. The method for locating the mobile device comprises: receiving a message at the hub that identifies the mobile device to be located; discriminating among communications signals received from each of the distributed antennas using a channel and a spreading code to identify a signal from the mobile device; identifying messages from the mobile device to be located; and determining which of the antennas is closest to the mobile device to be located by monitoring received signal strength of the identified signal.
1. A method for locating a mobile communications device in a distributed antenna system in which plural distributed antennas are communicatively coupled to a hub and in which the mobile device is communicatively coupled to the hub via one or more of the antennas, the method comprising:
receiving at the hub communication signals from the plural distributed antennas;
combining the received communication signals to produce a combined signal;
forwarding the combined signal to a base station, wherein the mobile device is communicatively coupled to the base station via the hub;
receiving a message at the hub that identifies the mobile device to be located;
discriminating, at the hub, among communications signals received from each of the distributed antennas using a channel and a spreading code to identify a signal from the mobile device; and
determining which of the antennas is closest to the mobile device to be located by monitoring received signal strength of the identified signal.
2. The method according to claim 1 , wherein the mobile device communicates using a CDMA protocol for cellular communications.
3. The method according to claim 1 , wherein the message identifies the mobile device according to its channel and the spreading code.
4. The method according to claim 1 , further comprising sending a notification of the location of the antenna determined to be closest to the mobile device for facilitating locating the mobile device.
5. The method according to claim 1 , wherein a notification is sent from an emitter associated with the antenna determined to be closest via a wireless personal area network.
6. The method according to claim 1 , wherein a notification is sent from an emitter associated with the antenna determined to be closest in the form of a human perceptible signal.
7. The method according to claim 1 , wherein the notification is sent via a wide area network.
8. The method according to claim 1 , wherein the monitoring of received signal strength of the identified signal is performed at the hub.
9. The method according to claim 1 , wherein the monitoring of received signal strength of the identified signal is performed at the antennas.
10. The method according to claim 1 , wherein a plurality of base stations are coupled to the hub and further comprising queuing the message at the hub until a prior request to locate a mobile device has been processed.
11. A distributed antenna system comprising:
a base station configured for communication with a telecommunications network;
a multi-port hub connected to the base station that receives communication signals on a plurality of ports of the multi-port hub from a plurality of distributed antennas and combines the received communication signals for forwarding a combined signal to the base station, wherein the multi-port hub comprises:
a de-spreader that uses a spreading code to identify a signal from a mobile communications device to be located; and
a controller that determines which of the antennas is closest to the mobile device to be located by monitoring received signal strength of the identified signal.
12. A method for locating a mobile device in a distributed antenna system in which plural distributed antennas are communicatively coupled to a hub and in which the mobile device is communicatively coupled to the hub via one or more of the antennas, the method comprising:
receiving at the hub communication signals from the plural distributed antennas;
combining at the hub the received communication signals to produce a combined signal;
forwarding the combined signal from the hub to a base station, wherein the mobile device is communicatively coupled to the base station via the hub;
receiving an indication at the hub that notifies the hub of commencement of locating the mobile device;
instructing the mobile device to modulate its output power;
identifying, at the hub, a received signal from the mobile device having modulated output power; and
identifying a particular antenna unit among the plurality having a highest received power level for the received signal from the mobile device having modulated output power.
13. The method according to claim 12 , wherein the mobile device communicates using a CDMA protocol for cellular communications.
14. The method according to claim 12 , wherein the indication is a message that identifies the mobile device according to its frequency channel or according to its frequency channel and timeslot.
15. The method according to claim 12 , wherein the mobile device communicates using a TDMA protocol for cellular communications.
16. The method according to claim 12 , further comprising sending a notification of the location of the antenna determined to be closest to the mobile device for facilitating locating the mobile device.
17. The method according to claim 12 , wherein a notification is sent from an emitter associated with the antenna determined to be closest via a wireless personal area network.
18. The method according to claim 12 , wherein a notification is sent from an emitter associated with the antenna determined to be closest in the form of a human perceptible signal.
19. The method according to claim 12 , wherein the notification is sent via a wide area network.
20. The method according to claim 12 , wherein the identifying the received signal from the mobile device having modulated output power is performed at the hub.
21. The method according to claim 12 , wherein the identifying the received signal from the mobile device having modulated output power is performed at the antennas.
22. The method according to claim 12 , wherein a plurality of base stations are coupled to the hub and wherein the indication is set in a register until a prior request to locate a mobile device has been processed.
23. A distributed antenna system comprising:
a base station configured for communication with a telecommunications network; and
a multi-port hub connected to the base station that receives communication signals on a plurality of ports of the multi-port hub from a plurality of distributed antennas and combines the received communication signals for forwarding a combined signal to the base station, wherein the multi-port hub determines which of the antennas is closest to a mobile device to be located by the base station by instructing the mobile device to modulate its output power, the hub identifying a received signal from the mobile device by its modulated output power, and identifying a particular antenna unit among the plurality having a highest received power level for received signal from the mobile device by its modulated output power.
24. A method for locating a mobile communications device in a distributed antenna system in which plural distributed antennas are communicatively coupled to a hub and in which the mobile device is communicatively coupled to the hub via one or more of the antennas, the method comprising:
receiving at the hub communication signals from the plural distributed antennas;
combining at the hub the received communication signals to produce a combined signal;
forwarding the combined signal from the hub to a base station, wherein the mobile device is communicatively coupled to the base station via the hub;
receiving a message at the hub that identifies the mobile device to be located;
identifying, at the hub, a received signal from the mobile device in a frequency channel and timeslot of the mobile device; and
determining which of the antennas is closest to the mobile device to be located by monitoring received signal strength of the identified signal.
25. The method according to claim 24 , wherein the mobile device communicates using a TDMA protocol for cellular communications.
26. The method according to claim 24 , wherein the message identifies the mobile device according to its frequency channel and timeslot.
27. The method according to claim 24 , further comprising sending a notification of the location of the antenna determined to be closest to the mobile device for facilitating locating the mobile device.
28. The method according to claim 24 , wherein a notification is sent from an emitter associated with the antenna determined to be closest via a wireless personal area network.
29. The method according to claim 24 , wherein a notification is sent from an emitter associated with the antenna determined to be closest in the form of a human perceptible signal.
30. The method according to claim 24 , wherein the notification is sent via a wide area network.
31. The method according to claim 24 , wherein the monitoring of received signal strength of the identified signal is performed at the hub.
32. The method according to claim 24 , wherein the monitoring of received signal strength of the identified signal is performed at the antennas.
33. The method according to claim 24 , wherein a plurality of base stations are coupled to the hub and further comprising queuing the message at the hub until a prior request to locate a mobile device has been processed.
34. A distributed antenna system comprising:
a base station configured for communication with a telecommunications network; and
a multi-port hub connected to the base station that receives communication signals on a plurality of ports of the multi-port hub from a plurality of distributed antennas and combines the received communication signals for forwarding a combined signal to the base station, wherein the multi-port hub determines which of the antennas is closest to a mobile device to be located by identifying a received signal from the mobile device by its frequency channel and timeslot, and identifying a particular antenna unit among the plurality having a highest received power level for the received signal from the mobile device.