Method and apparatus for removing FSK in-band signaling

Method and apparatus for ringing

Method and apparatus for spectral containment over telephone...

Method and apparatus for spectral containment over telephone...

Method and apparatus for stabilization of a line powered...

Method and apparatus for subscriber line control circuit

Method and apparatus for supplying power to a twisted pair...

Method and apparatus for transmitting white noise for echo cance

Method and arrangement for choosing supply voltage

Method and arrangement for supplying direct current to a telepho

Method and circuit arrangement for compensating cross-talk and/o

Method and circuit arrangement for controlling a subscriber...

Method and circuit arrangement for detecting speech in a telepho

Method and circuit for echo-cancellation in two-way...

Method and device for analysis of a return signal and adaptive e

Method and device for echo cancellation using power...

Method and device for power supply in telecommunication systems

Method and device for transmitting a transmission signal via...

Method and system for controlling echo cancellation using...

Method and system for data communication