Adaptive call progress tone detection system
Adaptive method and apparatus for detecting a stutter dial tone
Answer supervision and service selection
Apparatus and method for audible signaling tone recognition
Apparatus and method for determining a minimal time bound...
Apparatus and method for noise immunity during signal detection
Apparatus and robust method for detecting tones
Apparatus for drawing and processing electrical power from a com
Call progress decoder for multiple cadenced tones on telephone l
Called party response detecting apparatus
Circuitry for recognizing two-tone compound signals in telephone
Communications device including an improved CPE alerting...
CPE alert signal tone detector
Cross-frame dual tone multifrequency detector
Detection of multifrequency tone signals
Devices, software and methods for passing DTMF signals under...
Dial pulse digit detector
Digital multifrequency signal receiver
Disabling tone detector for network echo canceller
DTMF detection having sample rate decimation and adaptive tone d