[sdiy] Information Content of Signals

[Paul Schreiber]

In a previoius life, I was a modem designer :)

If you REALLY want to read about how modems use all sorts of bizarre modulation schemes
(including ISDN, DSL, microwaves, etc) the holy grail is:

"Advanced Digital Communications" by Kamilo Feher, Prentice-Hall.

This is an easy-to-read book (well, relatively speaking) that has 100's of USEFUL graphs
explaining the pros and cons of like 20 different modulation schemes. He has a very easy to read
style, like Bob Pease. Feher has other books on cell phone schemes (CDMA versus TDMA).

It also answers the question "What good is all this calculus for anyway? I'll NEVER use it!" It's
nice to see how elegant these modulations schemes are, and how you can calculate the performance.
Well, *I* thought it was elegant :)

Also, many telcom digital base-band encoding schemes are *specifically* engineered for reducing
crosstalk in copper wiring. I spent many an hour in MathCAD calculating 50-pair crosstalk for
different schemes. Gack!

Paul S.