Method and apparatus for detecting a telephone CPE alerting signal

• US 6,122,353 A
• Filed: 07/14/1997
• Issued: 09/19/2000
• Est. Priority Date: 12/13/1994
• Status: Expired due to Term

• Current Assignee: Dies Cellular LLC (Intellectual Ventures LLC)
• Original Assignee: CIDCO, Inc. (EarthLink Incorporated)
• Inventors: Brady, Robert H., Zielski, David, Nutter, William L., Marra, Alexander J.
• Primary Examiner(s): Kuntz, Curtis A.
• Assistant Examiner(s): Barnie, Rexford N.
• Application Number:
  US08/892,102
• Time in Patent Office: 1,163 Days
• Field of Search: 379/142, 379/215, 379/351, 379/236, 379/237, 379/257, 375/256, 364/724.09
• US Class Current: 379/142.08
• CPC Class Codes: H04M 1/573 Line monitoring circuits for detecting caller identification
• CPC Class Codes: H04M 19/041 Encoding the ringing signal, i.e. providing distinctive or selective ringing capability
• CPC Class Codes: H04M 3/428 Arrangements for placing incoming calls on hold

Abstract

A method and apparatus for verifying that a CAS (Customer Premises Equipment Alerting Signal) detect signal, which indicates the presence of a CAS on a transmission channel, is a valid detect signal, includes structure and process steps for suppressing a signal originating at a local telephone in response to the CAS detect signal. A determination is made whether the CAS detect signal remains in a predetermined condition at a predetermined time after the local telephone signal is suppressed. A validity signal is output when the CAS detect signal remains in the predetermined condition at the predetermined time. False detections are thereby minimized by ignoring detections caused by a signal originating at the local telephone.

Claims

1. An apparatus for detecting, at a user'"'"'s location adjacent a telephone or integral with the telephone, a valid incoming CAS (Customer Premises Equipment Alerting Signal) on a transmission channel, said apparatus comprising:

means for receiving at the user'"'"'s location an incoming signal including the CAS;

means for processing the incoming signal to detect the CAS;

means for determining whether the detected CAS is caused by a signal originating at the user'"'"'s location or by the incoming signal; and

means for generating an acknowledge signal when said means for determining determines that the detected CAS is caused by the incoming signal.

2. A method of detecting, at a user'"'"'s location adjacent a telephone or integral with the telephone, a valid incoming CAS (Customer Premises Equipment Alerting Signal) on a transmission channel, comprising the steps of:

receiving at the user'"'"'s location an incoming signal including the CAS;

processing the incoming signal to detect the CAS;

determining whether the detected CAS is caused by a signal originating at the user'"'"'s location or by the incoming signal; and

generating an acknowledge signal when said determining step determines that the detected CAS is caused by the incoming signal.

3. An apparatus tor verifying that a CAS (Customer Premises Equipment Alerting Signal) detect signal, which indicates the presence of a CAS on a transmission channel, is a valid detect signal, said apparatus comprising:

means for Suppressing a signal originating at a local telephone in response to the CAS detect signal;

means for detecting whether the CAS detect signal changes condition in response to suppression of the local telephone signal; and

means for outputting a validity signal when said means for detecting detects no change in the condition of the CAS detect signal in response to suppression of the local telephone signal.

4. A method of verifying that a CAS (Customer Premises Equipment Alerting Signal) detect signal, which indicates the presence of a CAS on a transmission channel, is a valid detect signal, said method comprising the steps of:

suppressing a signal originating at a local telephone in response to the CAS detect signal;

detecting whether the CAS detect signal changes condition in response to suppression of the local telephone signal; and

outputting a validity signal when said means for detecting detects no change in the condition of the CAS detect signal in response to suppression of the local telephone signal.