I just started looking into RF literally a couple of days ago (never done
anything with it in the past), and I understand that it's a very
complicated topic, but I have a few questions/thoughts:

I understand how basic analog (AM, FM) and digital (OOK, ASK, FSK, PSK)
modulation techniques work (not the underlying mathematics yet, but
probably enough to build one) and I bet I could make a very simple digital
RF transceiver. I have a few questions.

1. Forgive me for asking, but what's stopping me from using a 2.4GHz VCO
and sending in a 100Mhz (100Mbit/s) data stream into the input pin and
receiving it on the other end (via FSK)? There just /has/ to be some
gotcha, because it seems simple enough. I know I should be able to send in
at least a 1Hz data stream and see it reliably, but where does the data
speed limit come in, other than the effects of nearing carrier wave
frequency?

2. Why are all these modules (http://www.hoperf.com/rf_fsk/fsk/) and most
other cheap RF modules only up to 250kbit/s? What's stopping them from
being run at 10Mbit/s?

3. My goal here is to build a short range (less than 100m, more like 10m
tops) digital RF transmitter receiver pair from scratch. The fancy
frequency hopping interference detection stuff is not yet a priority. I'd
be happy building a simple channel-selector switch based 2.4 GHz RF pair.
I'm guessing FSK is a good way to go and dropped/corrupted packets
shouldn't be an issue as long as *most* of the data goes through. All I
need it to do is send a PCM stream of audio with minimal latency at
an application throughput of around 3Mbit/s. Maybe things like using
multiple channels at lower bitrate is a possibility, or high bitrate with
error correction stuff (redundancies) packed into the stream.

4. Failing the above, my next idea would be a VCO based analog FM
transmitter, which I suppose is pretty hard to mess up.

5. I'd like to stick to the 2.4GHz bands (or 900MHz if 2.4GHz isn't
possible) for either option #3 or #4 to keep antenna length short
and propagation properties from preventing the signal from going too far
out of my walls.

Dove into a huge, dark, lake that is RF, and no idea where I am or what to
do, and can't see anything. Just my thoughts. Hoping to get some advice.
--=20
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