Hi Paul

Steve VK2ZTO has done a lot of work in low data rates but I dont know
about spread spectrum.

His webpage is http://www.users.on.net/~pastol

Cheers Bob Vk2YQA

Paul Rubin wrote:
I wonder if there's much reason to be interested in ultra-low-speed
digital radio, by which I mean two or three bits per second, or even 1
bps, using spread spectrum modulation over a voice channel or across a
whole band. The idea is to have a reasonably reliable HF
communications channel for portable, low-powered equipment in remote
areas. You'd use data compression so that a 100 character text
message would compress down to maybe 40 bytes. At 2 bits/sec, sending
the 40 bytes would take about 2.5 minutes, maybe a little longer if
you add some FEC. 100 characters in 2.5 minutes is about 5 words per
minute, a speed which has proven usable to novice ham CW operators for
many decades.