Using a wireless phone 160ft underground?

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A user seeks advice on enabling a wireless phone to operate 160 feet underground in a non-operational mine, utilizing a 2000-foot Cat5e cable connected to a surface base station. Experts highlight that Cat5e cable is unsuitable for transmitting DECT 6 signals at 1.9 GHz over such distances due to significant signal loss. Suggestions include placing a base unit in the mine to minimize loss and using a wired landline or a separate base unit for underground communication. Alternatives like a Wi-Fi-based system connected via Ethernet or exploring cellular repeaters are also discussed. The conversation emphasizes the importance of signal amplification and suitable technology for underground communication.
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Hello all, I'm not all that savvy with radio antennas, or physics in general, so I've come to kindly ask for your expertise in solving a problem that I'm working on.

Basically, I'm looking for a relatively simple way to get a wireless portable phone to work in an underground cavern of a small non operational mine. The decline ramp into the mine is roughly 2000ft long with a line of cat5e magnetically shielded network cable along the run. At the surface is the wireless base station. I'm wanting to use the network cable with antennas on each end to carry the signal. Is this possible to essentially have the underground portable phone wirelessly transmit to the underground end of the cable then travel 2000ft (vertical distance from surface is 160ft) to an antenna that is situated right next to the base station where it is relayed to it? Any one able to speculate on what kind of components I'd need? Do I need to amplify the signal in such a case? It may also be possible to wire the phone into the cord

The phone system uses the Dect 6 standard if that is of any assistance.

Thank you again if anyone is able to share their knowledge.

Cheers!
 
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You don't say which country you're writing from so I will assume the United States. Cat5e cable is limited to 100 MHz and even then not for lengths of 2000 ft. In the U.S. cordless phones using DECT 6 operate at 1.9 GHz. Cat5e cable at 1.9 GHz would have so much loss the signal wouldn't go very far.

Why couldn't you put the base unit in the mine also and connect the base's phone connection to the cat5e cable? The cable will have orders of magnitude less loss at audio than at 1.9 GHz. Also the phone base unit will be feeding many orders of magnitude more signal into the cable than will an antenna.
 
Hi, I'm actually in Canada, but the standards are the same I believe.

I can't put the base unit in the mine because it serves other wireless extensions above ground. I may just have to set it up as a separate land line it looks like. Thanks for your input though :)
 
I've never tried this or even heard of it being done, but couldn't you get an extra base unit for down in the mine and wire the land line output as an extension of the base unit above ground?
 
How about a WI FI based system above and below ground, connected by a wired ethernet link? The system is referred to as SIP and you use it just like a telephone system - dialling in and out transparently. Voice over Internet Protocol. It could be a turnkey project for you.
 
Would a http://en.wikipedia.org/wiki/Cellular_repeater" work in this case?

Edit: I misread. You're not using a cell phone. Maybe they have something similar that would work with this cordless phone setup?
 
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