CVSD Military Speech Codec

CVSD (Continuously Variable Slope Delta Modulation) Codec

Adaptive Digital’s CVSD Codec is used in both commercial and military communications where “toll-quality” is required, yet low computation complexity and low memory requirements are desirable.  As the name implies it is Delta modulation (DM*) with variable step size. A method by which a voice signal is digitized for transmission, and then changed back to an analogue voice signal during reception. The size of the steps of the approximated signal is progressively increased or decreased as required to make the approximated signal closely match the input analog wave. 

CVSD is a full-duplex voice codec based on Continuously Variable Slope Delta Modulation, a form of delta modulation that dynamically adjusts its step size to closely track changing speech signals. By continuously adapting to signal variations, CVSD achieves efficient voice encoding while maintaining clear and intelligible speech reproduction.

Its low computational requirements, robustness, and real-time performance make CVSD particularly well suited for embedded systems, portable devices, radio communications, and other applications where processing resources and bandwidth may be limited.

Key Benefits

• Full-duplex CVSD voice codec
• Low-complexity voice compression
• Minimal memory and processing requirements
• Toll-quality speech performance
• Real-time voice encoding and decoding
• Adaptive variable-step delta modulation
• Suitable for embedded and resource-constrained systems
• Proven technology for commercial and military communications

*Delta-modulation (DM) is a differential waveform quantization or coding technique. A DM encoder uses the error between the original signal to be coded and the coded signal itself to create a differentially quantized data stream. Codec