Apparatus and methods for managing access and update requests in a wireless network

• US 8,259,659 B2
• Filed: 07/03/2008
• Issued: 09/04/2012
• Est. Priority Date: 07/03/2008
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Luft, Achim, Bienas, Maik
• Primary Examiner(s): ROSE, KERRI M
• Application Number:
  US12/217,433
• Publication Number:
  US 20100002582A1
• Time in Patent Office: 1,524 Days
• Field of Search: 370229-232, 370/330, 370335-337, 370342-345, 370/347, 370/480, 370/498, 455/422.1, 455/432.1, 455/433, 455/435.1, 455/436, 455/440, 455/441, 455/456.1, 455/456.5, 455/456.6
• US Class Current: 370/329
• CPC Class Codes: H04W 74/002 Transmission of channel access control information
• CPC Class Codes: H04W 74/0833 Random access procedures, e.g. with 4-step access
• CPC Class Codes: H04W 74/0841 with collision treatment
• CPC Class Codes: H04W 74/0866 using a dedicated channel for access

Abstract

Methods and apparatus that enable a wireless network to detect and manage impending congestion events caused by a plurality of mobile devices attempting to access the network in a brief space of time. In one embodiment, the network comprises a 3g (UMTS) cellular network, and includes a congestion management and avoidance entity that preemptively triggers a collision mode upon detecting an impending congestion event. This mode advantageously reduces processing burden on the base station by causing the mobile devices (UEs) to halt current access attempts, and invoke a multiple access scheme (e.g., wait a random amount of time before attempting further access attempts). The comparatively early detection and avoidance of collisions reduces the mobile device'"'"'s power consumption, while addressing congestion events early in the wireless communication process so as to maintain optimal network conditions.

Claims

1. A method of operating a cellular communication system so as to avoid simultaneously receiving an excessive number of requests for a service on a first channel, comprising:

sending a message on a second channel,

where said message results in a staggering of said requests by a randomized period of time;

where the staggering of said requests is completed via a relay station; and

wherein said relay station causes said staggering of said requests for service on a first channel whenever the number of said requests exceeds a prescribed threshold value.

2. The method of claim 1, wherein said cellular system comprises a third generation (3G) system, said first channel comprises a Random Access Channel (RACH), said second channel comprises an Acquisition Indicator Channel (AICH), and said excessive number of requests are triggered by the substantially simultaneous crossing of a geographic boundary by a plurality of users of said 3G system.

3. The method of claim 1, wherein said message sent on said second channel is indicative of a collision between two or more of said requests when in fact such requests had no such collision.

4. A computer readable apparatus comprising a storage medium storing at least one computer program, the at least one program comprising a plurality of instructions which, when executed by a processing device:

monitor an access channel of a wireless network to determine a number of wireless devices that intend to issue an access request message; and

send a plurality of response messages on a synchronization channel of the wireless network at least when the number of wireless devices that intend to issue an access request message exceeds a threshold value;

wherein the plurality of response messages impose a multiple access scheme on subsequent access request messages from the wireless devices;

wherein said multiple access scheme is configured to stagger said access request messages; and

wherein the staggered access requests are completed via a relay station.

5. The computer readable apparatus of claim 4, wherein the threshold value corresponds to a level of network congestion value that would substantially degrade the operation of the wireless network.

6. The computer readable apparatus of claim 5, wherein the computer readable apparatus comprises a storage device of a relay station within the wireless network.

7. The computer readable apparatus of claim 6, wherein the network comprises a third generation (3G) cellular network, the access channel comprises a Random Access Channel (RACH), the synchronization channel comprises an Acquisition Indication Channel (AICH), and the monitoring of the access channel comprises monitoring for Radio Resource Connection (RRC) or Location Area/Routing Area (LA/RA) update requests from the wireless devices.

8. The computer readable apparatus of claim 6, wherein the apparatus is configured to disable uplink and/or downlink communications at the relay station when the number of wireless devices that intend to issue an access request message exceeds a threshold value.

9. A base station apparatus for use within a cellular communication system, the base station apparatus configured to avoid simultaneously receiving an excessive number of requests for a service on a first channel, the apparatus comprising:

processor apparatus;

at least one wireless interface in data communication with the processor apparatus; and

computerized logic in data communication with the processor apparatus, the logic configured to send a message on a second channel, said message resulting in a staggering of said requests by a randomized period of time;

wherein;

the staggering of said requests is performed at least in part via a relay station; and

said relay station causes said staggering of said requests for service on a first channel whenever the number of said requests exceeds a prescribed threshold value.

10. The base station apparatus of claim 9, wherein said cellular communication system comprises a third generation (3G) system, said first channel comprises a Random Access Channel (RACH) channel, said second channel comprises an Acquisition Indicator Channel (AICH) channel, and said excessive number of requests are triggered by the substantially simultaneous crossing of a geographic boundary by a plurality of users of said 3G system.

11. The base station apparatus of claim 9, wherein said message sent on said second channel is indicative of a collision between two or more of said requests when in fact such requests had no such collision.

12. A method of operating a wireless network, comprising:

monitoring an access channel of the wireless network to determine a number of wireless devices that intend to issue an access request message; and

sending a plurality of response messages on a synchronization channel of the wireless network at least when the number of wireless devices that intend to issue an access request message exceeds at least one specified criterion;

wherein;

the plurality of response messages caused imposition of a multiple access scheme on subsequent access request messages from the wireless devices; and

the multiple access scheme is configured to stagger said access request messages, the staggered access requests being performed at least in part using a relay station.

13. The method of claim 12, wherein the at least one criterion relates at least in part to a level of network congestion that would substantially degrade the operation of the wireless network.

14. The method of claim 13, wherein the network comprises a third generation (3G) cellular network, the access channel comprises a Random Access Channel (RACH).

15. The method of claim 13, wherein the synchronization channel comprises an Acquisition Indication Channel (AICH), and the monitoring of the access channel comprises monitoring for Radio Resource Connection (RRC) or Location Area/Routing Area (LA/RA) update requests from the wireless devices.

16. The method of claim 13, wherein the apparatus is configured to cause disabling of uplink and/or downlink communications at the relay station when the number of wireless devices that intend to issue an access request message exceeds at least one second criterion.

17. A base station apparatus for use within a cellular communication system, the base station apparatus configured to manage simultaneous receipt of a number of requests for a service on a first channel, the apparatus comprising:

processor means;

at least one means for wireless communication in data communication with the processor means; and

computerized logic in data communication with the processor apparatus, the logic configured to send a message on a second channel, said message resulting in a staggering of said requests according to a prescribed staggering scheme;

wherein the staggering scheme is implemented at least in part via a network relay means whenever the number of said requests meets or exceeds a prescribed criterion.