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Passive DAS Test

Passive DAS Test

Passive DAS Test

So my company built a new facility which acts like a Faraday cage for all cell signals. We've ruled out active DAS and pico/femto cells as options due to cost. That leaves passive DAS. Management doesn't want to waste money, but also doesn't want to go without cell service.

I'm trying to mock up a passive DAS - a yagi pointed to a cell tower with a radiator indoors. All I have on hand are 2.4Ghz antennas... Would I be able to prove the concept using those antennas? How effective is a 2.4 specific antenna in picking up 3G signals, or not at all?

Sorry for the likely crazy question. I just need to be able to justify spending a few thousand bucks that is proved in small scale with a few hundred...


RE: Passive DAS Test

So, you're counting on an external antenna to pick up the signal, run that down a cable, then re-radiate the signal inside the building? It's not my field, but that's probably going to suck. The effective antenna drive is going to be miniscule, so the signal is going to be miniscule.

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RE: Passive DAS Test

That's pretty much what I was thinking... If I can make if work somewhat, even if it sucks I can justify a repeater like the MRx18 from Commscope (RF Repeater).

RE: Passive DAS Test

Mr Stuff is exactly correct. Passive re-radiation is highly ineffective except over extremely short distances on either one side or the other. This can be demonstrated by elementary pathloss analysis.

Good news: (Active) Cell Phone Repeaters are now (recently) very cheap (Canada The Source for example). You need to beware of the various bands, various providers, etc. It's possible that you might make some people happy, but fail to make everyone happy.

RE: Passive DAS Test

So I ruled out the passive idea - I talked management into a Wilson electronic amp/antenna for a proof of concept test for the smaller building. I'll let you know how it goes.


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