Method for automatically adapting levels of signals...
Method for electrically simulating a cradle switch and a hands f
Method for fail-safe operation in a speaker phone system
Method for gain control in telephone sets having an electronic s
Method for noise dosimetry in appliances employing earphones...
Method for reducing noise from a non-linear device that...
Method for the control of voice channel attenuation
Method of and device for echo cancellation
Method of improving sidetone attenuation in electroacoustic syst
Methods and apparatus for improving voice quality in an...
Microphone/loudspeaker having a speakerphone mode and a micropho
Microprocessor-controlled full-duplex speakerphone using...
Microprocessor-controlled full-duplex speakerphone using...
Modular subscriber device
Multi-channel echo canceler
Multi-function telephone apparatus and control method
Multi-tone signal discriminator
Multirate speech codecs