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'Advanced Multi-Band Excitation' ('AMBE') is a very powerful proprietary speech coding standard developed by Digital Voice Systems, Inc..

Contents

Features

Technology

History

Usage

Licensing

External links

Features

AMBE operates at very low bitrates of between 2000 and 9600 bit/s.
The audio data is usually combined with up to 7.200 bit/s of forward error correction data. Lost frames can be masked by using the parameters of the previous frame to fill in the gap.
AMBE has a low complexity, lower than CELP format.

Technology

AMBE is based on Codebooks and works at a sampling rate of 8 kHz in frames of 20 ms.

History

1980 Multi-Band Excitation (MBE) was developed at the MIT. DVSI improved MBE-technology which led to their ''Improved Multi-Band Excitation'' (IMBE). AMBE is the further improved successor of it.

Usage

It is used by the Inmarsat and Iridium satellite telephony systems, certain channels on XM Satellite Radio, Charles Brain's (Call sign: G4GUO) protocol for high frequency amateur radio and is the speech coder for OpenSky Trunked radio systems.

Licensing

AMBE is controversial in that the licensing terms are very restrictive. While a licensing fee is due for most codecs, DVSI does not disclose software licensing terms. Anecdotal evidence suggests a minimum fee from $100,000 to $1 Million. PC implementations are not allowed. For the purposes of comparison, MP3's licensing starts at $15,000. For small-scale use and prototyping, the only option is to purchase a dedicated hardware IC from DVSI.

External links

★ http://www.dvsinc.com/products/software.htm