Method of dynamically populating a neighbor list in a wireless communication system

• US 7,848,292 B2
• Filed: 06/29/2006
• Issued: 12/07/2010
• Est. Priority Date: 06/29/2006
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Alcatel-Lucent USA, Inc. (Nokia Corporation)
• Inventors: Dajer, Miguel, Bl, Ql, Yang, Yang, Ye, Sigen
• Primary Examiner(s): Negrón; Daniell L
• Assistant Examiner(s): Nguyen; Huy D
• Application Number:
  US11/427,621
• Publication Number:
  US 20080002628A1
• Time in Patent Office: 1,622 Days
• Field of Search: 455/436, 455/437, 455/438, 455/439, 455/440, 455/442, 455/443, 455/423, 370/331, 370/332
• US Class Current: 370/331
• CPC Class Codes: H04W 36/00835 Determination of neighbour cell lists
• CPC Class Codes: H04W 36/18 for allowing seamless reselection, e.g. soft reselection

Abstract

The present invention provides a method of dynamically forming a neighbor list in a wireless communication system. Embodiments of the method may include forming a neighbor list associated with at least one sector based on information provided by at least one mobile unit.

Claims

1. A method, comprising:

modifying, at an entity in a wireless communication system, a neighbor list associated with at least one first sector associated with at least one antenna of a base station, the neighbor list being modified using time dependent information transmitted over an air interface to the entity by at least one mobile unit.

2. The method of claim 1, wherein modifying the neighbor list comprises modifying the neighbor list using information indicative of at least one measurement of a time dependent pilot signal performed by said at least one mobile unit.

3. The method of claim 2, wherein modifying the neighbor list comprises adding at least one second sector to the neighbor list based on said at least one measurement of a time dependent pilot signal associated with said at least one second sector by said at least one mobile unit.

4. The method of claim 3, wherein adding said at least one second sector to the neighbor list comprises adding said at least one second sector to the neighbor list if a strength determined by said at least one measurement of the time-dependent pilot signal exceeds a first threshold strength.

5. The method of claim 2, wherein forming the neighbor list comprises removing at least one second sector from the neighbor list based on said at least one measurement of a pilot signal associated with said at least one second sector by said at least one mobile unit.

6. The method of claim 5, wherein removing said at least one second sector from the neighbor list comprises removing said at least one second sector from the neighbor list if a strength of said at least one pilot signal falls below a second threshold strength.

7. The method of claim 1, wherein modifying the neighbor list comprises modifying the neighbor list based on information transmitted over the air interface to the entity by at least one mobile unit that is or has been in soft handoff between at least two sectors.

8. The method of claim 1, comprising forming an initial neighbor list based on at least one of a geographical network layout map, a theoretical model of radiofrequency propagation loss, and an empirical model of radiofrequency propagation loss, and wherein modifying the neighbor list comprises modifying the initial neighbors list in response to fluctuating radio frequency propagation characteristics of at least one pilot signal monitored by said at least one mobile unit.

9. The method of claim at 8, wherein dynamically modifying the initial neighbor list comprises modifying the initial neighbor list based on the information transmitted over the air interface to the entity in the wireless communication system by said at least one mobile unit.

10. The method of claim 9, wherein modifying the neighbor list comprises modifying the neighbor list in response to receiving the information transmitted by said at least one mobile unit.

11. A method, comprising:

forming a neighbor list associated with at least one first sector associated with at least one antenna of a first base station, the neighbor list being formed based on information provided by at least one mobile unit by adding, at least one second sector to the neighbor list when a number of measurements of a strength of, at least one pilot signal from said at least one second sector exceeds a first threshold strength more than a predetermined number of times.

12. A method, comprising:

forming a neighbor list associted with at least one first sector associated with at least one antenna of a first base station, the neighbor list being formed based on information provided by at least one mobile unit by removing, at least one second sector from the neighbor list if a number of measurements of a strength of, at least one pilot signal from said at least one second sector falls below a second threshold strength more than a predetermined number of times.

13. A method, comprising:

providing time dependant information from at least one mobile unit over an air interface to an entity in a wireless communication system such that the entity can use the time dependent information to dynamically modify a previously determined neighbor list associated with at least one sector associated with at least one antenna of a first base station, wherein said at least one sector includes said at least one mobile unit.

14. The method of claim 13, wherein providing the time dependent information comprises providing information indicative of at least one measurement of a time dependent pilot signal performed by said at least one mobile unit.

15. The method of claim 14, wherein providing the time dependent information comprises providing information indicative of at least one time dependent signal strength of the time dependent pilot signal.

16. The method of claim 14, comprising performing a plurality of measurements of a plurality of time dependent pilot signals associated with said at least one sector and at least one other sector during soft handoff between said at least one sector and said at least one other sector.

17. The method of claim 16, comprising receiving a combined neighbor list associated with said at least one sector and said at least one other sector involved in the soft handoff.

18. The method of claim 17, wherein performing the plurality of measurements comprises performing a plurality of time dependent measurements on a plurality of pilot signals associated with sectors indicated in the combined neighbor list.