Improving Cell Phone Reception In Buildings? 8
Amphigory asks: "Not too long ago, I got a digital cell phone. Unfortunately, this phone simply doesn't work in my office even though it works in other parts of the building and even outside the building. For a variety of reasons, I would really like it to. What I'd like to be able to do is put some kind of antenna or maybe a retransmitter from my office to the roof of the building that would allow the signal to get through. Has anybody out there ever done anything like this?" I've heard of systems like this for large convention centers, but I'm not aware of the details. Can anyone shed some light on this subject?
Re:"Leaky" RF Conduits (Score:1)
pick up a personal antenna (Score:2)
We are having one of those building-wide antenna systems installed here, but they are MUCHO DINERO. And I doubt your company would spring for it if, as you say, the reception is pretty godo everywhere else in the building.
you can pick up a little antenna ata cell phone store or I'm sure Radio Shack, I've seen them for under $50. They're meant for cars but they really would work anywhere: The one I've used is a small car-phone like antenna, about 8" long, magnetic base, and a wire about 10' long you plug into the back of the phone. You can leave the antenna in the office and plug into it when youre there. It works very, very well in the car, even in long tunnels where I couldn't anything previously.
Re:pick up a personal antenna (Score:2)
New Windows (Score:3)
If you have access to the outside of a window, you might try two automotive stick-on cellphone antennas. The antenna on the rear window of a car is transformer-coupled to the cable inside the car, so you might try two of those back-to-back. If you have cooperative building maintenance personnel, in an inconspicuous corner you could try scraping off a little of the coating where you fasten the antennas, to allow better leakage between the antennas. The building staff might be happy to have a way to get phones to work inside the building. I don't know how many antennas might be needed for an area -- I don't have access to such a building.
"Leaky" RF Conduits (Score:3)
Passive or active (Score:3)
I have seen passive re-radiators- essentially just a pair of antennas with a cable in between- which might help, but you need to get some pretty high quality cable between the antennas, because the cable losses at the PCS frequencies (up near 2 GHz are pretty high). (I'm guessing this is a PCS or some other non-traditional-cellular (800-900 MHz) cellular phone, since building construction is much less friendly to letting the PCS frequencies through).
For a passive re-radiator to work well, you need to place an antenna outside (not behinid a window- many windows have metallic coatings that will kill RF), preferably in full view of your local cellular phone tower. Run the absolutely shortest cable you can to your inside antenna. Both antennas must be tuned to the frequency of interest. Unfortunately, since celluar phones are frequency agile or spread spectrum, you want antennas that have a somewhat wide band around the frequency band- don't forget that transmit and recieve from the tower may be on separate frequency bands.
-OR- work hard and get a window office. This is probably the most effective solution to your problem.
Indoor transceivers (Score:3)
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This is what I do. (Score:4)
If you're asking what you can do by yourself, the short answer is not much. If you're realitivly close to an area of good reception, you could string an external antenna along, but I can't see that being terribly practical. Also, call up your provider, and tell them that you have no inbuilding coverage at your location. I recieve these reports, and use them to assist in locating new sites. Better yet, do it a couple of times.
If your company owns the building you work in, AND it has a fair amount of phones from whatever provider you use, then talk to your building managment, and give your provider a call. My company has build several microcells upon the request of companies that have bought phones from us. If you can get that accomplished, you'll almost certianly get excellent coverage.