TWELP^™ Vocoders

DSP Innovations (DSPINI) announces new class of proprietary vocoders for wide range of bit rates from 300 bps up to 9600 bps, based on the newest speech coding technology TWELP™, for Digital Radio (HF, DMR, dPMR, etc.) and other markets.

TWELP technology features.
The vocoder is based on newest technology of speech coding called "Tri-Wave Excited Linear Prediction" (TWELP) that was developed by experts of DSPINI. The technology provides the best speech quality among competitors today, thanks to:

• Advance reliable method of Pitch estimation
• Pitch synchronous analysis
• Advance tri-wave model of excitation
• Newest quantization schemes
• Pitch synchronous synthesis

In spite of the fact, that TWELP technology is based on well-known LPC-method, where output speech is gotten by the synthesizing LPC-filter, it is not a variety or combination of well-known speech coding methods, patented comprehensively during last 30 years.
TWELP is unique three-component representation of pitch-synchronous LPC residual that is quantized by unique speech-driven quantizers in conjunction with LPC-parameters.
New technology allows to achieve much better speech quality in comparison with any known speech coding methods on the same bit rates (from 300 bps up to 9600 bps and wider).