Field Guide · algorithm

Also known as: multi-band excitation, MBE

Multi-band excitation (MBE) is a speech-modelling method that represents a voice by its pitch and a decision, per frequency band, of whether that band is voiced (pitched) or unvoiced (noisy), plus the spectral envelope.1

VVUVUV voiced (V) / unvoiced (U) decision per band
Multi-band excitation models speech as a pitched spectrum with a voiced/unvoiced flag per band — the basis of IMBE/AMBE.

How it works

Transmitting these compact parameters lets the receiver re-synthesise intelligible speech at a few kbps. MBE underlies the IMBE and AMBE / AMBE+2 vocoders from DVSI.

Relevance to SDR

Understanding MBE explains why decoded digital voice can sound robotic and why bit errors produce characteristic warbles.

Sources

  1. Multi-Band Excitation — Wikipedia, for the speech model with per-band voiced/unvoiced decisions underlying IMBE/AMBE. ↩

See also

Learn it step by step

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