> It were me, I'd probably look into Bluetooth-
or Zigbee-based serial
> extenders.
I'm not sure about Zigbee, but the useful range of
Bluetooth is very
short. There are claims of over 30 meters, but as far as I can tell
that must be under laboratory conditions, e.g. in a faraday cage.
In the real world, more than about 3 meters line of sight works poorly,
as does non-line-of-sight at any distance.
Well, 30 meters is probably with the full gale laboratory tailwind, but
I accidentally left the phone behind and went down the hall 15+ meters in
this pile of a building where I work (brick and plaster walls, often
seems made mostly of Faradayium) and my bt headset didn't lose
connection. So it does have some range sometimes. Success would
definitely depend on the devices in question and the construction of the
building. I don't know if Zigbee has better range or not.
De