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Propagating a Signal Through Old Walls?

Posted by Cliff on from the guiding-signals dept.

avjewe asks: "I have a wireless (802.11) network in my 100 year old house. The walls are thick plaster, with enough metal in them to block the signal quite effectively. The floors, however, pass the signal just fine. Does anyone have any experience or suggestions as to how one can propagate a signal through a maze of faraday cages? I recently added an omni-directional antenna which, as one would expect, boosted the signal where I already had one, but didn't help the dead spots."

8 of 64 comments (clear)

  1. Re:use the walls themselves... by j1m+5n0w · · Score: 4, Informative
    I dont know if its possible, but could you actualy use the metal in the walls as an antenna?

    If the antenna isn't properly matched to the radio you can end up with high SWR (standing wave ratio), which could potentially damage the radio. The energy, instead of being transmitted out the antenna, gets reflected back to the transmitter, which can cause it to overheat. That's my understanding, at least. If someone else knows better, feel free to correct me.

    -jim

  2. Re:Instant PowerLine Etherfast 10/100 Bridge by mrscott · · Score: 3, Informative

    I happen to have experience with many of the various powerline home networking options. Actually, they're VERY cool, and will probably work even on your old cabling. If you're just trying to get one remote system up and running, you'd need two (one for the computer and one to connect to your router - all via Ethernet) and they're around $70 each or so.

    They're not speed demons at 4-8Mbps in real life, but still faster than broadband and not a bad choice at all.

  3. Short and simple summary and solutions... by stienman · · Score: 4, Informative

    Your problem is that you want to get network access to all parts of your home with a minimum of fuss, ideally wireless.

    The walls prevent a single wireless access point from working throughout your home.

    Your implicit question is: How can I, without investing in more equipment, get wireless throughout the home?

    The answer is: You cannot.

    Solutions:

    1) Place multiple access points throughout the home. Honestly, you can get one for $19 now - why are you so worried about it?

    2) Wire passive repeaters throughout the home. Get two 802.11 antennas, put one on each side of the various offending walls, and connect them with their very short cables through the wall. Not great, causes other small problems, but recent radios and APs can sort those out with some loss in quality and speed.

    3) Use APs with two antennas, and mount an antenna on each side of one wall. Means you don't have to have an AP for each section, one AP can serve two sections.

    4) Use wireless bridges and repeaters - again, one antenna on each side of a wall.

    5) Use an amplifier with your AP. DLink, Linksys, etc - they all have amps. Mount the AP and both antennas in the attic. Spread the antennas out, 20-30 feet apart to get the largest cover area.

    6) Use a powerline to wireless adaptor, and place them all over the place. Should be able to buy these very cheaply online now.

    There are many other solutions, but these are the ones that come to mind readily and should be easily implementable by even the most technophobic individual.

    Hopefully you know how to repair cracks and holes in plaster.

    -Adam

    1. Re:Short and simple summary and solutions... by Anonymous Coward · · Score: 1, Informative

      "Use APs with two antennas, and mount an antenna on each side of one wall. Means you don't have to have an AP for each section, one AP can serve two sections."

      You evidently don't know why an AP has two antennas. Typically one is used for transmitting, the other for receiving. Putting one on either side of the wall is a great solution... if you want half-duplex operation.

      Chuck

  4. Re:multiple antennas by curious.corn · · Score: 2, Informative

    that would whack the impedance of the output line. Even if you retuned the line with some passive component you'd end up with nasty losses, reflections on the bifurcations and phase interference between the antennas; this kind of stuff is only worthwhile if you're making a phased array (now that'd be fun: make an access point that tracks your position and target enough power to your receiver. but you're still linited by your laptop antenna range & power).

    --
    Mi domando chi à il mandante di tutte le cazzate che faccio - Altan
  5. You already HAVE the wiring! by Jeremiah+Cornelius · · Score: 2, Informative
    You need a home powerline network!

    The MacWireless Powerline Network Adapter allows you to route your network through the electrical lines in your home or office. With speeds up to 10 times faster than DSL, this is a great way to get your ethernet network to other floors or rooms in your building, without the need to run wires. Powerline Network Adapters are particularly useful when concrete, metal, or other obstructions in the walls of your home or office block your wireless signals.
    --
    "Flyin' in just a sweet place,
    Never been known to fail..."
  6. Make use of this... by Anonymous Coward · · Score: 1, Informative

    http://webphysics.davidson.edu/Applets/Poisson/Far aday.html

  7. electrical tape-- or-- by way2trivial · · Score: 2, Informative
    I convinced my wife (easily) we needed crown molding in the babies room.. (it's between my office and the master bedroom) she readily agreed to add it to the list of renovations for that room, (she was 'nesting' dontcha know)

    then she agreed to the cables run behind the molding...
    3 strands of cat 5, and 5 rca lines... wheee!

    --
    every day http://en.wikipedia.org/wiki/Special:Random