Digital Voice Systems Inc. (DVSI) ), Introduces
the AMBE-4020™ Full-Duplex Vocoder Chip

Westford, Mass – Digital Voice Systems, Inc. (DVSI) the recognized leader in the development of low-data-rate speech compression technology today announced it is shipping its newest full-duplex vocoder chip the AMBE-4020™ Full-Duplex. The launch of this device compliments the highly successful low-cost, half-duplex AMBE-4020™ Vocoder Chip with the same small footprint and minimal power requirements. Building on DVSI's line of compact vocoder chip solutions the AMBE-4020™ Full-Duplex delivers performance and reliability that exceeds the typical demands of digital communication systems.

The AMBE-4020™ Full-Duplex is a full-duplex implementation of DVSI's patented AMBE+2™ Voice Compression Algorithm. With the flexibility of operating at data and FEC rates from 2.0 to 9.6 kbps users can optimize system design to provide excellent voice quality with superior robustness to bit errors and acoustic background noise.

The AMBE-4020™ Full-Duplex Vocoder Chip offers the same performance and features found in the half-duplex AMBE-4020™ Vocoder Chip including: an interface for low-cost digital mic, typical low-power operation: encoder 28mW, decoder 18 mW, sleep <15µW, push-to-talk signaling to ease design of half-duplex systems, and numerous advanced design features such as, automatic Voice/Silence Detection (VAD), adaptive comfort noise insertion (CNI), DTMF and Call Progress Tone detection/regeneration, and low power modes. With a 16-bit ADC and 12-bit DAC built-in, the AMBE-4020™ Full-Duplex Vocoder chip simplifies additional hardware requirements. The AMBE-4020™ Full-Duplex vocoder chip's small form factor (80-pin LQFP or 121 MAP BGA package are available) can be easily incorporated into an ultra-low-power base band circuit where circuit board real estate is at a premium. Additionally, the AMBE-4020™ Full-Duplex Vocoder Chip provides flexibility in design configurations by including serial interfaces for vocoder configuration, status information, and, transferring speech and compressed data bits to/from the chip's encoder and decoder.

"The AMBE-4020™ Full-Duplex vocoder chip is a great addition to DVSI's family of vocoder products." said Bob Maher, DVSI's director of sales and marketing. "When engineers are designing digital communication systems where bandwidth is at a premium and high quality voice is critical to success, DVSI has best solution to meet their needs."

Digital Voice Systems, Inc. specializes in the development of low-bit-rate, high quality voice compression products incorporating their patented IMBE™, AMBE® AMBE+™ and AMBE+2™ Voice Compression Technologies. DVSI software and hardware voice compression solutions are successfully implemented in both private and standards-based digital communication systems worldwide. DVSI's Speech Compression technology is the core component that enables original equipment manufacturers to produce innovative designs with an array of advanced features. Additional company information and product details can be found online at www.dvsinc.com.

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AMBE™, AMBE+™ and AMBE+2™ are registered trademarks and trademarks of Digital Voice Systems, Inc. and are protected by US and other patents and patents pending.