Method and apparatus for concurrent monitoring of divergent wireless telecommunication systems

• US 6,826,400 B1
• Filed: 09/11/1998
• Issued: 11/30/2004
• Est. Priority Date: 06/07/1995
• Status: Expired due to Fees

• Current Assignee: Pacific Communication Sciences , Inc. (Cirrus Logic Incorporated)
• Original Assignee: Pacific Communication Sciences , Inc. (Cirrus Logic Incorporated)
• Inventors: Cashman, Russell P., Schwartz, Richard A.
• Primary Examiner(s): CUMMING, WILLIAM D
• Application Number:
  US09/151,580
• Time in Patent Office: 2,272 Days
• Field of Search: 455/423, 455/551, 455/434, 455/552, 455/574, 455/553, 455/452.1, 455/552.1, 455/553.1, 380/48, 370/350, 370/352, 370/329
• US Class Current: 455/434
• CPC Class Codes: H04W 36/0088 Scheduling hand-off measurements
• 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 76/20 Manipulation of established connections
• CPC Class Codes: H04W 88/06 adapted for operation in multiple networks or having at least two operational modes, e.g. multi-mode terminals

Abstract

A portable communications subscriber unit operates as a data transfer terminal as well as an analog cellular telephone M-ES. Two modes of operation, an analog cellular communication mode and a Cellular Digital Packet Data (CDPD) mode, are available in the subscriber unit. The subscriber unit distinguishes between paging signals indicative of a CDPD mode of communication and those indicative of an analog cellular mode of communication. The subscriber unit automatically preempts CDPD communications in favor of analog cellular communications such as those carried out in an AMPS system. The present inventive method enables the subscriber unit to remain registered in the CDPD communication system using a CDPD “sleep mode” while performing activities on the AMPS system. Another aspect of the present invention facilitates the automatic switching of subscriber unit displays to correspond to the communication system with which the unit is presently communicating.

Claims

1. A method for concurrently monitoring communications in a first cellular communication system and a second cellular communication system, comprising the steps of:

a. registering a wireless subscriber station for communication in both the first and the second communication systems;

b. communicating in the first system until there is a lack of activity in the first system for a first predetermined time period;

c. entering a sleep mode in the first system;

d. communicating in the second system for a second predetermined time period; and

e. exiting the sleep mode in the first system and proceeding to step b.

2. The method of claim 1, wherein the first communication system is a cellular digital packet data (CDPD) system.

3. The method of claim 1, wherein the second communication system comprises an analog mobile phone system (AMPS).

4. The method of claim 1, wherein the first predetermined time period is T203 seconds, and wherein a value for T203 is set by the subscriber station and received by the subscriber station using the first communication system.

5. The method of claim 1, wherein the second predetermined time period is a product of N204 and T204, and wherein values for N204 and T204 are received by the subscriber station over the first communication system.

6. The method of claim 1, wherein the sleep mode is exited by the subscriber station when the subscriber station transmits a polled receiver ready (RR) signal to the first communication system.

7. The method of claim 1, wherein the second communication system comprises a time division multiple access (TDMA) system.

8. The method of claim 1, wherein the first communication system comprises a code division multiple access (CDMA) system.

9. The method of claim 1, wherein the second communication system conforms with the IS-136 specification.

10. The method of claim 1, wherein the second communication system comprises a GSM communication system.