Use of cellular digital packet data (CDPD) communications to convey system identification list data to roaming cellular subscriber stations

• US 6,128,489 A
• Filed: 03/26/1999
• Issued: 10/03/2000
• Est. Priority Date: 12/04/1995
• Status: Expired due to Term

• Current Assignee: Verizon Patent and Licensing Incorporated (Verizon Communications Inc.)
• Original Assignee: Bell Atlantic Network Services, Inc. (Verizon Communications Inc.)
• Inventors: Seazholtz, John W., Farris, Robert D.
• Primary Examiner(s): Bost, Dwayne D.
• Assistant Examiner(s): PERSINO, RAYMOND B
• Application Number:
  US09/276,751
• Time in Patent Office: 557 Days
• Field of Search: 455/426, 455/466, 455/432, 455/433, 455/553, 455/434, 455/423, 455/455, 455/525, 455/419, 370/349
• US Class Current: 455/432.1
• CPC Class Codes: H04W 48/08 Access restriction or access information delivery, e.g. discovery data delivery signalling during connection H04W76/00
• CPC Class Codes: H04W 48/16 Discovering, processing access restriction or access information
• CPC Class Codes: H04W 52/0245 according to signal strength
• CPC Class Codes: H04W 8/183 Processing at user equipment or user record carrier
• CPC Class Codes: H04W 8/205 Transfer to or from user equipment or user record carrier
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

An analog cellular voice telephone system and subscriber stations associated therewith are controlled to conserve power and to provide alternate service carriers. Acquisition of all of the service carriers is facilitated through the use of system identification numbers (SIDs) associated with each service carrier. A roaming subscriber will tune to a cellular digital packet data (CDPD) frequency to obtain a list of service carriers operating within that geographical area. Based upon a comparison with a preferred SID list stored in the subscriber station, an available service carrier will be selected by the subscriber station, and registration with the selected service carrier will take place. Usually, analog voice communication is suspended until the selection process takes place.

Claims

1. A method of registering a radio telephone subscriber unit on an analog cellular voice radio communication system, said analog cellular voice communication system having a plurality of cell sites for communication with a plurality of radio telephone subscriber units over a plurality of radio frequencies in at least one of a plurality of frequency bands, and being controlled by at least one controller, said method comprising the steps of:

(a) generating a system identification number (SID) associated with each of said plurality of frequency bands and service carriers associated therewith;

(b) broadcasting a list of said generated SIDs on a cellular digital packet data (CDPD) channel in a data stream constituted by;

(i) an initial block with recognition data;

(ii) temporary equipment identifier (TEI) data;

(iii) system control data;

(iv) communication information data;

(v) channel identification data; and

(vi) said generated SID list;

(c) at a radio telephone subscriber unit selecting a SID based upon a comparison of said generated SID list received in said data stream by said radio telephone subscriber unit and a list of preferred SIDs stored in said radio telephone subscriber unit;

(d) registering with an analog cellular voice system corresponding to said selected SID; and

(e) operating said radio telephone subscriber unit to remain in sleep mode with response to CDPD operation.

2. The method of claim 1, wherein said generated SID list is contained within said initial block.

3. The method of claim 1, wherein said generated SID list is contained within said control data.

4. The method of claim 1, wherein said generated SID list immediately precedes said channel ID.