Mobile communication system with position detection to facilitate hard handoff

• US 7,031,711 B2
• Filed: 09/17/2001
• Issued: 04/18/2006
• Est. Priority Date: 11/06/1998
• Status: Expired due to Fees

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Soliman, Samir S.
• Primary Examiner(s): Nguyen, Lee
• Application Number:
  US09/954,910
• Publication Number:
  US 20020034947A1
• Time in Patent Office: 1,674 Days
• Field of Search: 455/456, 455/410, 455/411, 455/565, 455/432, 455/435, 455/457, 455/456.1, 455/436, 455/438, 455/440, 342/450
• US Class Current: 455/438
• CPC Class Codes: H04W 36/08 Reselecting an access point
• CPC Class Codes: H04W 36/083 wherein at least one of the access points is a moving node
• CPC Class Codes: H04W 36/32 by location or mobility data, e.g. speed data
• CPC Class Codes: H04W 36/322 by location data

Abstract

A system for facilitating handoff adapted for use with a telecommunications network. The system includes position equipment for determining the location of a mobile transceiver within a region containing a first cell and a second cell. A comparison circuit compares the location with a predetermined handoff area within the region and provides a control signal in response thereto. A handoff initiation circuit initiates handoff of the mobile transceiver between the first cell and the second cell in response to the control signal. In a specific embodiment, the handoff is a hard handoff. The position equipment includes Global Positioning System (GPS) equipment including a mobile unit GPS receiver and signal interface. The comparison circuit includes a positional database that stores latitudinal and longitudinal information corresponding to the predetermined handoff area. The comparison circuit also includes a Code Division Multiple Access selector. The selector begins tracking the position of the mobile transceiver when it is within a predetermined range of the predetermined handoff area. In a specific embodiment, the handoff initiation circuit includes a base station controller. The position equipment includes a base station positional detection system and a mobile unit positional detection system for determining the location of the mobile transceiver. The position database has map information depicting the coverage area of the first and second cells and the predetermined handoff area. The selector runs software for comparing the location to the map information and providing the control signal when the location is within the predetermined handoff area. The base station includes and implements instructions for completing hard handoff in response to the control signal.

Claims

1. A base station controller for facilitating hard handoff comprising:

a position database configured to store information corresponding to locations of a plurality of handoff regions; and

a selector bank subsystem configured to initiate tracking of the position location of a mobile unit upon detection of a pilot signal corresponding to a region near a handoff region of the plurality of handoff regions, without regard to pilot signal strength, to track the location of the mobile unit using at least partially a GPS system, to determine when the mobile unit enters the handoff region according to the stored information and the location of the mobile unit, and to initiate handoff when the mobile unit enters the handoff region.

2. The base station controller of claim 1, wherein the selector bank subsystem determines when the mobile unit enters the handoff region by comparing the position location of the mobile unit to the information corresponding to the location of the handoff region.

3. The base station controller of claim 1, wherein the selector bank subsystem is further configured to identifying a target cell for receiving the handoff based upon the position location of the mobile unit.

4. A method of handoff comprising:

initiating tracking of the position location of a mobile unit upon detection of a pilot signal corresponding to a region near a handoff region, without regard to pilot signal strength;

tracking the location of the mobile unit using at least partially a GPS system;

determining when the mobile unit enters the handoff region according to stored information and the location of the mobile unit; and

initiating handoff when the mobile unit has entered the handoff region.

5. The method of claim 4, wherein determining when the mobile unit has entered a handoff region comprises comparing the position location of the mobile unit to information corresponding to the location of the handoff region stored in a position database.

6. The method of claim 4 further comprising identifying a target cell for receiving the handoff based upon the position location of the mobile unit.

7. An apparatus comprising:

means for initiating tracking of the position location of a mobile unit upon detection of a pilot signal corresponding to a region near a handoff region, without regard to pilot signal strength;

means for tracking the location of the mobile unit using at least partially a GPS system;

means for determining when the mobile unit enters the handoff region according to stored information and the location of the mobile unit; and

means for initiating handoff when the mobile unit has entered the handoff region.

8. The method of claim 7, wherein means for determining when the mobile unit has entered a handoff region comprises means for comparing the position location of the mobile unit to information corresponding to the location of the handoff region stored in a position database.

9. The method of claim 7 further comprising means for identifying a target cell for receiving the handoff based upon the position location of the mobile unit.