Method for controlling channel reselection

• US 6,501,951 B2
• Filed: 05/07/1999
• Issued: 12/31/2002
• Est. Priority Date: 12/24/1996
• Status: Expired due to Term

• Current Assignee: AT&T Mobility II LLC (AT&T, Inc.)
• Original Assignee: AT&T Wireless Services Incorporated (AT&T, Inc.)
• Inventors: Moore, Michael R.
• Primary Examiner(s): CUMMING, WILLIAM D
• Application Number:
  US09/306,760
• Publication Number:
  US 20010044301A1
• Time in Patent Office: 1,334 Days
• Field of Search: 455/439, 455/522, 455/552, 455/435, 455/575, 455/452, 455/63, 455/455, 455/454, 455/426, 455/422, 455/451
• US Class Current: 455/434
• CPC Class Codes: H03J 1/005 in a loop
• CPC Class Codes: H03J 1/0091 provided with means for scanning over a band of frequencies H03J1/0058 takes precedence
• CPC Class Codes: H04W 36/06 Reselecting a communication resource in the serving access point

Abstract

A method for re-selecting control channels in a mobile station reduces the use of resources by limiting an evaluation of candidate control channels to those channels which satisfy certain criteria and are deemed to be eligible control channels. As a consequence, resources are not spent on attempting to re-select a control channel that is not compatible with the mobile station.

Claims

1. In a system in which a mobile station operating on a first control channel can re-select another control channel, a method for controlling a re-selection process comprising:

(b) receiving a list of candidate control channels;

(b) determining from the list if any of said candidate control channels are ineligible for re-selection by belonging to a private network to which the mobile station is not permitted access;

(c) analyzing candidate control channels in said list to identify a primary candidate control channel where analyzing is performed only with respect to those candidate control channels not determined to be ineligible for re-selection by belonging to the private network to which the mobile station is not permitted access;

(d) re-selecting said primary candidate control channel.

2. The method of claim further comprising:

(e) if re-selecting said primary candidate control channel fails, then determining said primary candidate control channel to be ineligible if the failed re-selection is attributable to a predetermined event.

3. The method of claim 2 further comprising:

after failing to re-select said primary candidate control channel

(f) determining if there are any secondary candidate control channels; and

(g) if there are no secondary candidate control channels repeating (b) to (d).

4. The method of claim 2 wherein said predetermined event comprises a mismatch between the service sought by the mobile station and the service provided by the primary candidate control channel.

5. The method of claim 2 wherein said primary candidate control channel corresponds to a private system and the predetermined event comprises the mobile station being incompatible with said private system.

6. In a process of controlling a mobile station'"'"'s re-selection of a control channel, a method for modifying a list of candidate control channels, the method comprising:

determining from the list if any of the candidate control channels are incompatible with the mobile station by belonging to a private network to which the mobile station is not permitted access; and

marking as ineligible those candidate control channels determined to be incompatible with the mobile station by belonging to the private network to which the mobile station is not permitted access;

wherein once a candidate control channel is marked ineligible it is ignored by the re-selection process.

7. The method of claim 6 wherein the mobile station does not belong to any private system and any control channel associated with a private system is deemed to be incompatible.

8. The method of claim 6 wherein a control channel is deemed incompatible when there is a mismatch between a service it provides and a service sought by the mobile station.