| |
KA9LCF > NEWS 24.08.12 21:55l 28 Lines 1005 Bytes #999 (0) @ ALLIN
BID : 38194-KA9LCF
Read: GUEST
Subj: ARN: Radio Technology
Path: IZ3LSV<IK6IHL<IK6ZDE<VE3UIL<J39BS<9Y4PJ<N9LYA<KA9LCF
Sent: 120824/0508Z 38194@KA9LCF.#NEIN.IN.USA.NOAM [169278]FBB7.01.35 alpha $:38
From: KA9LCF@KA9LCF.#NEIN.IN.USA.NOAM
To : NEWS@ALLIN
RADIO TECHNOLOGY: AN FDMDV OPEN SOURCE 1400 BPS HF MODEM
David Rowe, VK5DGR, has made available open source software
for a 1400 bps High Frequency FDMRV modem.
FDMDV stands for Frequency Division Multiplexed Digital
Voice and is described as basically being a grouping of slow
modems running in parallel. For example FDMDV has 14
carriers spaced 75 Hz apart, each running at 50 symbols a
second. Due to multipath problems on the High Frequency
bands this approach is claimed to work better than one
carrier running at 700 symbols per second.
One of the applications of this modem technology will be
Digital Voice since it offers fast sync, no multi-second
training sequences, the ability to recover quickly after a
fade, and no automatic re-transmit of "bad" packets.
Those interested in experimenting with HF digital voice
using this technology can find further information and
source code at tinyurl.com/hf-digital-voice-modem
(Southgate)
Read previous mail | Read next mail
| |
