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Is there a way to transmit data throughout my house without RF?

My application: I want to spread sensors and actuators in my home. Due to the nature of these things I do not need high data rates, a dozen bits per second might be well enough.

My house is very massive with concrete walls and ceilings, so RF has mostly just a one-room-range.

I thought about using the existing water pipes as acoustic audio couplers, but is there a better way?

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    \$\begingroup\$ "RF has mostly just a one-room-range." I'm listening to a radio program now and the transmitter is 100 km away. Also, you are looking for a 2-way system. You want to transmit and receive. \$\endgroup\$ – Transistor Feb 27 '16 at 11:36
  • \$\begingroup\$ infrared sensor would be nice for small range. \$\endgroup\$ – koolwithk Feb 27 '16 at 12:08
  • \$\begingroup\$ @Andy and transistor: As I emphasized, this is a problem of my home, not RF in general. I'm well aware of radio and satellites. But in my home there is no cell phone signal if you are more than a few feet away from the next window and I use three Wifi repeaters to have it work in all important rooms, so I figured the massive walls might be the reason. \$\endgroup\$ – Kapt. Brackbier Feb 27 '16 at 12:21
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    \$\begingroup\$ I do not want to make a fuzz of it, but why not start answering for solutions instead of nitpicking? I think I layed out in simple terms why I have come to the conclusion why RF is not a viable solution in my case and Dave seems to have understood the gist of it. \$\endgroup\$ – Kapt. Brackbier Feb 27 '16 at 13:06
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    \$\begingroup\$ You might try powerline networking. \$\endgroup\$ – Robert Stiffler Feb 27 '16 at 13:13
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Use powerline networking, X10, etc.

User lower frequencies which penetrate walls better than higher frequencies, such as the 433 MHz band rather than 2.4 or 5 GHz.

Drill holes, run wires, put a wireless access point in each room.

Run fiber optics or wire everywhere, connect all your sensors and devices via fiber optics or wires. Also known as (hammer) Drill, baby, drill.

If " LiFi " ever gets past the hype stage it might offer an option (you'd need to pass it through doorways, or course), but at present it looks like lots of hype, no product, though I suppose you could use the concept to roll your own system.

It would be kinda retro-cool to have speaking tubes all over the house connected to 300 baud acoustic couplers, but it might also get a little wearing (background noise-wise) unless you have really good acoustic isolation, and of course if you had the tubes in place, they'd make perfectly good conduits.

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  • \$\begingroup\$ If there is steel mesh in the walls acting as a Faraday cage, there's no reason to think that lower frequencies would work any better. Generally speaking, mesh shielding only starts to pass frequencies whose wavelengths are comparable to (or shorter than) the size of the mesh openings. Powerline networking is probably the most viable option. \$\endgroup\$ – Dave Tweed Feb 27 '16 at 13:19
  • \$\begingroup\$ If there's a mesh that is the problem. I can state for an observed fact that 5 GHz and a non-mesh concrete wall does much worse than 2.4 GHz which does much worse than 900 MHz. I infer that 433 MHz would probably be better in that case. It's still far above the FM broadcast band, which is what we used as a crude test of the effectiveness of any modifications to the screen rooms in the lab, back in the day, so I suspect any normal concrete mesh is far too large to be an effective Faraday cage for those frequencies. \$\endgroup\$ – Ecnerwal Feb 27 '16 at 13:26
  • \$\begingroup\$ See: physics.stackexchange.com/questions/149607/… \$\endgroup\$ – Ecnerwal Feb 27 '16 at 13:33
  • \$\begingroup\$ Cogitating slowly today - and if a portable FM radio works inside the house, lower frequencies do work better there, QED. So that (rather than a higher-frequency cell phone) would be a good test to try. \$\endgroup\$ – Ecnerwal Feb 27 '16 at 14:02
  • \$\begingroup\$ So far, no one has stated that broadcast radio works in the house. \$\endgroup\$ – Dave Tweed Feb 27 '16 at 14:34
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I built a Power Line Carrier (PLC) Modem as a student project some 20 years back and it worked quite well for a few kbps. I used Hyper-terminal to demonstrate data transmission to about 100 ft. That was with standard technology available 20 years back (LM1893/2893). I am sure there is much improved signal processing and electronics now. OFDM can provide robust communication and high data rates.

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