TDM = Time Domain Multiplexing

WDM = Wide Dimensional Multiplexing

SDM = Statistical Domain Multiplexing.

TDM and, to a limited degree, WDM have been around and used for several
decades in high performance networking. SDM is relatively new, about 5
years.

There are far more ways to multiplex intelligence on a medium than PSK and
FSK, although both are used in high performance systems.

You are 100% correct... I may very well a few decimal places off... The
mathematical models show that 100 Mbps should be possible in as little as 10
KHz.

Take Care & 73
--
From The Desk Of
Marty Albert, KC6UFM


"Dana H. Myers" wrote in message
...
Marty Albert wrote:
As I recall, at 23 cm and 80 Mbps we had an effective bandwidth of
around
100 KHz on the "final" design... That design incorporated TDM, limited
SS,
and WDM of the signals.

What exactly does this all mean?

Passing 80,000,000 bits/sec in 100,000Hz of bandwidth sounds
pretty fantastic - to the extent that makes me question the
validity of the measurements.

Today, we could use TDM, WDM, SDM, high-end SS, and a few other tricks
and,
assuming a target data-rate of 100 Mbps, get the on air bandwidth down
to
around 50-75 KHz, maybe even a little less.

Whoa. Hold on. Help me understand what units and methods
of measurement you're using. Right now, you're off by several
decimal places in even the most generous way.

Dana K6JQ