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
Measurement and uses of oxidative status
Sensor chip, sensor cartridge, and analysis apparatus
Blend polymer gas separation membrane
Maize hybrid X95C382
Method for forming contact in an integrated circuit
Method and system to generate finite state grammars using sample phrases
Method and receiver for jointly decoding received communication signals using maximum likelihood detection
  Randomly Featured Patents
Over the counter medicinal container with surface ornamentation
Mechanism and chair for powered combined and independent seat back and leg rest motion
LiPO3-based coating for collectors
Spatial low pass filter for range finding systems
Method for detecting the amount of grains within a grinding device
Multilayer ceramic electronic part and conductive paste
Uses of heptafluoropropane
System for indicating photographic information
Handle fixture