AT2004

AT2004 4 Channels ADPCM Processor with Echo Cancellation and Conferencing Atelic Systems, Inc. AT2004 Application Note Preliminary 4 Channels ADPCM Processor with Echo Cancellation and Conferencing Version 1.0 January 29, 2001 Description The AT2004 is a four full-duplex channels, ADPCM processor with conferencing and echo cancellation capabilities. It follows the G.726 ITU Standard for ADPCM compression for 40k, 32k, 24k and 16k bitrates with selectable µ-law and Alaw input/output. It conforms to ITU G.165/G.168 Digital Adaptive Echo Canceller specification for line echo delay up to 20ms. Using the command serial interface, each individual half-channel can be independently configured for ADPCM, conferencing and echo canceling features. Features 4 full channels of ITU G.726 ADPCM 4 full channels of ITU G.165/G.168 complia nt echo cancellation with up to 20ms echo delay Fast and robust convergence for adaptive echo canceller, even in the presence of background noise Nonlinear processing with adaptive suppression threshold and comfort noise generation for echo canceller Per channel selectable µ-Law and A-law input/output On-chip time slot assignment Available internal clock generator and frame sync. generator Simple 3-wire serial command port for chip configuration Conferencing capabilities for up to 3 additional sound sources Applications DECT VoIP / VoDSL Wireless telephone systems Wireless PBX systems Default Settings 4 channels of µ...