System and method of UMTS UE location using uplink dedicated physical control channel and downlink synchronization channel

• US 8,331,956 B2
• Filed: 10/10/2011
• Issued: 12/11/2012
• Est. Priority Date: 10/06/2008
• Status: Active Grant

• Current Assignee: Bison Patent Licensing, LLC
• Original Assignee: Andrew LLC (CommScope Holding Company, Inc.)
• Inventors: Islam, Tariqul, Carlson, John, Al-Mufti, Khalid, HANNAN, Ariful
• Primary Examiner(s): WASHINGTON, ERIKA ALISE
• Application Number:
  US13/269,911
• Publication Number:
  US 20120028653A1
• Time in Patent Office: 428 Days
• Field of Search: None
• US Class Current: 455/456.1
• CPC Class Codes: G01S 5/0215 Interference
• CPC Class Codes: H04W 24/00 Supervisory, monitoring or testing arrangements
• CPC Class Codes: H04W 64/00 Locating users or terminals or network equipment for network management purposes, e.g. mobility management

Abstract

A system and method for estimating a location of a wireless device in a wireless communication system having a plurality of nodes and a plurality of location measurement units (“LMUs”). A set of signal samples from a first wireless device and a second wireless device may be collected by one or more LMUs in a search window. A first time of arrival (“TOA”) is determined, and a second search window is estimated as a function of the first TOA. A second TOA may be determined within the second search window at a second node or one of the LMUs from the set of signal samples. A range estimate of the wireless device may then be determined, and an estimated location of the wireless device may be determined as a function of the first uplink TOA, the second uplink TOA, or the range estimate and second TOA.

Claims

1. A method for estimating a location of a wireless device in a wireless communication system having a plurality of nodes and a plurality of location measurement units (“

LMU”

), the method comprising the steps of;

(a) collecting a plurality of signal samples from a first wireless device and a second wireless device by one or more LMUs in a first search window;

(b) determining a first time of arrival (“

TOA”

) from the plural signal samples;

(c) determining a second search window as a function of the first TOA;

(d) determining a second TOA from the plural signal samples in the second search window; and

(e) determining an estimated location of the first wireless device as a function of the first TOA or the second TOA.

2. The method of claim 1 wherein the plural signal samples include signal samples representing both uplink and downlink spectrums.

3. The method of claim 1 wherein the second TOA is an uplink signal TOA.

4. The method of claim 1 further comprising the step of providing a request to a geolocation control server to locate the wireless device in the communication system.

5. The method of claim 4 wherein the request includes tipping information.

6. The method of claim 5 wherein the tipping information is provided by the communication system.

7. The method of claim 5 wherein the tipping information is extracted from messages exchanged between the wireless device and a node.

8. The method of claim 1 wherein determining a first TOA further comprises:

(i) recreating an uplink pilot signal in at least one LMU; and

(ii) correlating the recreated uplink pilot signal against the plural signal samples.

9. The method of claim 1 wherein at least one LMU is not co-located with a respective node.

10. The method of claim 1 wherein the estimated location of the wireless device is determined as a function of a value selected from the group consisting of sector geometry and sector axis.

11. The method of claim 1 wherein the second search window is determined as a function of downlink dedicated physical channel frame timing or fractional dedicated channel frame timing.

12. The method of claim 1 wherein the second search window is determined as a function of round trip time and Rx-Tx time difference type 2 parameters.

13. The method of claim 1 wherein the nodes are selected from the group consisting of:

base stations, base station sectors, and combinations thereof.

14. The method of claim 1 wherein the communication system is selected from the group consisting of:

Universal Mobile Telecommunications System (“

UMTS”

) network, Worldwide Interoperability for Microwave Access (“

WiMax”

) network, Global System for Mobile Communications (“

GSM”

) network, Orthogonal Frequency Division Multiple Access (“

OFDMA”

) network, WiFi network, and Code Division Multiple Access (“

CDMA”

) network.

15. The method of claim 14 wherein the system operates under a standard selected from the group consisting of:

IS-95, Evolution-Data Optimized (“

EVDO”

), CDMA2000, Long Term Evolution (“

LTE”

) and 1 times Radio Transmission Technology (“

1×

RTT”

).