In 1967 Osamu Fujimura (MIT) showed basic advantages of the multi-band representation
of speech ("An Approximation to Voice Aperiodicity", IEEE 1968). This work gave a
start to development of the "multi-band excitation" method of speech coding,
that was patented in 1988 by founders of DVSI as "Multi-Band Excitation" (MBE).
Source:Wikipedia - Multi-Band Excitation
This early vocoder was patented by DVSI and is now sold under licence.
It is disappointing for the amateur radio hobby that the AMBE technology
became corporatised and therefore relatively expensive thus adding to the
cost of radio equipment that incorpoirate this technology.
A vocoder (voice encoder) is a category of voice codec that analyzes and synthesizes
the human voice signal for audio data compression, multiplexing, voice encryption, voice transformation
Source:https://en.wikipedia.org/wiki/Vocoder
[Top][Home]
Digital Voice Systems, Inc. (DVSI) is the supplier of Legacy Vocoders AMBE+™, AMBE®, IMBE™.
The DVSI Corporate Web Site:
http://www.dvsinc.com/soft_products/legacy.shtml
Digital Voice Systems, Inc. (DVSI) has been designing and producing speech compression technology since the 1980's when work began on a fundamentally different speech model known as Multi Band Excitation (MBE).
This is a homebrew evaluation board for AMBE-3000 and AMBE-3003 Chips. It can be used as a replacement for USB-3003 devices to work as a transcoder for XLX reflectors. This board is supported by the AMBEd daemon from version 1.2 onwards.
Details can be found on this github site: https://github.com/phl0/AMBE3003USB
Northwest Digital Radio supply the DV3000 board and ThumbDV(DV3000U) USB stick
and details can be found here:
http://nwdigitalradio.com/wp-content/uploads/2012/04/DV3000DS.pdf
Their products are available from their shop:
http://nwdigitalradio.com/shop/
A guide to setting up your NW Digital Radio DV3000 board can be found here:
Companion guide to AmateurLogic 75: DV3000 Raspberry Hot Spot
By Mike, VE3MIC 3/10/2015 SECOND EDITION
Another detailed guide to setting up your NW Digital Radio DV3000 board can be found here:
http://www.amateurlogic.com/downloads/DV3000.pdf
This installation makes use of "Open Dummy Repeater" application for the DV3000
and the git repository is here:git clone https://github.com/dl5di/OpenDV.git
It also makes use of Rasperry Pi Version of the IRCDDBGateway application
[Top][Home]
AMBE Exposed! by Bruce Perens K6BP bruce@perens.com
http://www.qsl.net/kb9mwr/projects/dv/codec/AMBE_Exposed.pdf
Decoding AMBE+2 in MD380 Firmware in Linux by Travis Goodspeed KK4VCZ
http://www.qsl.net/kb9mwr/projects/dv/codec/Decoding%20AMBE+2%20in%20MD380%20Firmware%20in%20Linux.pdf
[Top][Home]