rf everywhere
In sci.electronics.misc Tim Williams wrote:
Hmmm, not a big deal I suspect.
Build a general purpose RF block for, say, 2.45GHz BT or 802.11(etc), or
whatever. Give it handles to talk with anything (modulations, bit
streams, etc.), design and build it on a particular fab process, and like
magic, anything incorporating that block will also work. Monolithic
inductors can be fabricated with not very good Q at 2.45GHz (I think they
usually peak around Q = 10 or 20 around 5GHz), but enough to do "silicon
oscillators" and stuff. Voltage regulation (bandgap, or old school buried
zener) and temperature compensation are no-brainers, as ICs go. Want a
DDS? Just chuck some more IP at it! Then whatever ancillary function
(moisture, temperature sensor, etc.) simply plugs into this mess of
transistors and functions.
Quite crazy, as all that circuitry is squeezing into a few milimeters of
silicon, when a few decades ago it was, well of course it was migrating to
thick film before monolithic, but before that, it was all machined
cavities, hand-soldered RF transistors, and microstrip everywhere. I
years ago I was given a box of microwave "plumbing" from what may have
been a broadcast engineer. The stuff would have worked with microwaves or
hydraulic fluid. The guy who made the stuff seemed to be really good with
a jewelers saw, copper pipe, brass discs rods and solder.
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