Resources Contact Us Home
Dynamic balance control for telephone

Image Number 8 for United States Patent #6990194.

A telephone includes a transmit channel and a receive channel, each including a bank of sub-band filters having a VAD coupled one to each sub-band filter. Each VAD measures the spectral energy in a sub-band, compares the spectral energy to a first threshold, and produces an output signal representative of whether or not the first threshold is exceeded. The voice activity detector also includes a threshold circuit for calculating a dynamically adjustable noise threshold based upon averaged measured spectral energy. A wide band or system VAD monitors echo canceling circuitry to detect voice activity and double talk. A dynamic balance control circuit maintains the transmit and receive channels in a predetermined energy ratio during double talk.

  Recently Added Patents
Knife grip
Integrated touch screen
Compound semiconductor epitaxial structure and method for fabricating the same
Flexure with insulating layer isolating a portion of a metal substrate
Real-time pricing of shipping vendors
Direct converting apparatus, method for controlling the same, and control signal generation device
Method for specifying control curve parameters for controlling climatic environmental conditions of climate-controlled enclosed spaces
  Randomly Featured Patents
Extensible nonwoven facing layer for elastic multilayer fabrics
System and method of recovering from failures in a virtual machine
Antifreeze/coolant composition
Large area EL lamp
Portable timepiece
Electrical connector which has a wire aligning function and which can be reduced in size
Floor structure for the environment of a modular computer system
Innovation information management model
Pyridine derivative and pyrimidine derivative
Laser beam printer