Vocoder chip eases multi-rate voice compression
LONDON Digital Voice Systems has introduced the AMBE-3000 vocoder chip, a DSP based voice compression solution that is suitable for full or half-duplex, real and non-real time, communication systems.
The chip implements DVSI’s patented AMBE+2 voice compression algorithm which is used for many mobile radio programs including DMR in Europe and APCO Project 25 in North America. It is also used by satellite systems to provide superior voice quality at low bit rates. The chip can operate at virtually any data rate from 2.0 to 9.6 kbits/s. This allows the user to optimize speech and/or FEC rates within their system requirements to provide excellent voice quality with superior robustness to bit errors and acoustic background noise.
The AMBE-3000 provides full or half-duplex operation, automatic voice/silence detection (VAD), adaptive comfort noise insertion (CNI), DTMF and call progress tone detection/regeneration, echo cancellation, low power modes and frame-by-frame “on-the-fly” rate switching. As the latest addition to DVSI’s family of voice compression products, the AMBE-3000 has interoperable modes that provide a seamless migration path from systems already using DVSI’s AMBE-2000 and AMBE-1000 vocoder chips.
These features, combined with the chip’s low power consumption and small form factor (128 pin LQFP of BGA package), make the AMBE-3000 suitable for wireless applications where bandwidth is at a premium and low-data-rate, high-voice-quality is imperative.
The AMBE-3000 Vocoder chip is designed for easy integration, with set-up, control and operation through control pins or a packet interface. It provides the choice of a UART, a parallel port or a serial port for vocoder configuration, status information, as well as, transferring speech and compressed data bits to/from the chip’s encoder and decoder.
