Balancing paging load and tracking area updates

• US 9,485,701 B2
• Filed: 03/17/2015
• Issued: 11/01/2016
• Est. Priority Date: 03/08/2007
• Status: Active Grant

• Current Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Original Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Inventors: Wang, Peter S., Mukherjee, Rajat P., Wang, Jin, Somasundaram, Shankar, Miller, James M., Olvera-Hernandez, Ulises
• Primary Examiner(s): Wang, Ted
• Application Number:
  US14/660,450
• Publication Number:
  US 20150195761A1
• Time in Patent Office: 595 Days
• US Class Current: 1/1
• CPC Class Codes: H04W 36/04 Reselecting a cell layer in multi-layered cells
• CPC Class Codes: H04W 36/22 for handling the traffic
• CPC Class Codes: H04W 36/32 by location or mobility data, e.g. speed data
• CPC Class Codes: H04W 36/324 by mobility data, e.g. speed data
• CPC Class Codes: H04W 36/36 by user or terminal equipment
• CPC Class Codes: H04W 36/362 Conditional handover
• CPC Class Codes: H04W 4/08 User group management
• CPC Class Codes: H04W 68/00 User notification, e.g. alerting and paging, for incoming communication, change of service or the like
• CPC Class Codes: H04W 76/38 triggered by timers
• CPC Class Codes: H04W 8/186 Processing of subscriber group data
• CPC Class Codes: H04W 8/205 Transfer to or from user equipment or user record carrier
• CPC Class Codes: H04W 84/042 Public Land Mobile systems, e.g. cellular systems
• CPC Class Codes: H04W 84/105 PBS [Private Base Station] network H04W84/12 - H04W84/16 take precedence

Abstract

A method for assigning a tracking area (TA) is disclosed. A mobility state of a wireless transmit/receive unit (WTRU) is determined and the TA is assigned based on the determined mobility state. Also disclosed is a method for accessing a closed subscriber group (CSG) TA. A CSG TA identifier is received at a WTRU and is stored. A CSG TA broadcast is received and the broadcast CSG TA is accessed if an identifier of the broadcast CSG TA matches the stored CSG TA identifier. Also disclosed is a method for changing a mobility state of a WTRU. A current mobility state of the WTRU is determined and a predetermined metric of the WTRU is examined. The predetermined metric is evaluated to determine if the metric has crossed a threshold and the mobility state is changed based on the evaluated metric.

Claims

1. A wireless transmit/receive unit (WTRU) for use in a wireless communication network, the WTRU comprising:

circuitry configured to;

receive a list of closed subscriber group (CSG) cell identities that the WTRU is permitted to access;

camp on a CSG cell whose identity is not in the list; and

on a condition that the WTRU is camping on a CSG cell whose identity is not on the list, transmit a tracking area update request message to the wireless communication network; and

receive, in response, a tracking area update accept message from the wireless communication network;

wherein the WTRU is assigned to a plurality of Long Term Evolution (LTE) tracking areas and further wherein the plurality of LTE tracking areas are used at the edges of at least one of the plurality of LTE tracking areas.

2. The WTRU of claim 1, wherein the circuitry is further configured to transmit an indication that the WTRU has selected a CSG cell whose identity is not on the list.

3. The WTRU of claim 1, wherein the circuitry is further configured to periodically update a tracking area of the WTRU.

4. The WTRU of claim 3, wherein the circuitry is further configured to periodically update the tracking area in response to an expiration of a timer.

5. The WTRU of claim 1, wherein the circuitry is further configured to transmit mobility information.

6. The WTRU of claim 1, wherein the tracking area update accept message includes a new list of tracking area IDs assigned to the WTRU.

7. The WTRU of claim 1, wherein the circuitry is further configured to exchange non-access stratum (NAS) signaling.

8. The WTRU of claim 1, wherein the circuitry is further configured to transmit the tracking area update request message to balance a signaling load.

9. A method performed by a wireless transmit/receive unit (WTRU) for use in a wireless communication network, the method comprising:

receiving a list of closed subscriber group (CSG) cell identities that the WTRU is permitted to access;

camping on a CSG cell whose identity is not in the list; and

on a condition that the WTRU is camping on a CSG cell whose identity is not on the list, transmitting a tracking area update request message to the wireless communication network; and

receiving, in response, a tracking area update accept message from the wireless communication network;

wherein the WTRU is assigned to a plurality of Long Term Evolution (LTE) tracking areas and further wherein the plurality of LTE tracking areas are used at the edges of at least one of the plurality of LTE tracking areas.

10. The method of claim 9, further comprising transmitting an indication that the WTRU has selected a CSG cell whose identity is not on the list.

11. The method of claim 9, further comprising periodically updating a tracking area of the WTRU.

12. The method of claim 11, wherein the periodically updating the tracking area further comprises periodically updating the tracking area in response to an expiration of a timer.

13. The method of claim 9, further comprising transmitting mobility information.

14. The method of claim 9, wherein the tracking area update accept message includes a new list of tracking area IDs assigned to the WTRU.

15. The method of claim 9, further comprising exchanging non-access stratum (NAS) signaling.

16. The method of claim 9, further comprising transmitting the tracking area update request message to balance a signaling load.

17. A wireless transmit/receive unit (WTRU) for use in a wireless communication network, the WTRU comprising:

circuitry configured to;

receive a list of closed subscriber group (CSG) cell identities that the WTRU is permitted to access;

camp on a CSG cell whose identity is not in the list;

on a condition that the WTRU is camping on a CSG cell whose identity is not on the list, transmit a tracking area update request message to the wireless communication network;

receive, in response, a tracking area update accept message from the wireless communication network; and

periodically update the tracking area in response to an expiration of a timer.

18. The WTRU of claim 17, wherein the circuitry is further configured to transmit an indication that the WTRU has selected a CSG cell whose identity is not on the list.

19. The WTRU of claim 17, wherein the circuitry is further configured to exchange non-access stratum (NAS) signaling.

20. The WTRU of claim 17, wherein the circuitry is further configured to transmit the tracking area update request message to balance a signaling load.