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Would this theoretically be possible with femtocells and phone signals?
by bduerst 8y ago
Would this theoretically be possible with femtocells and phone signals?
- karambahh 8y agoYes but rogue femto cells for this purpose have been ruled illegal in France and, I believe, all EU countries. Retailers rollbacked to IR sensors and now are slowly adopting counters on cameras with deep learning for disambiguation.
- bigiain 8y agoYou don't want to get caught transmitting on cellular bands. You can do this with just receive though. A $10 USB TV Tuner and a Raspberry Pi will listen in to most cellular bands, and pull enough out of the over-the-air machine to machine chatter to do a similarly accurate job of counting cellphones... The cellular transmitters (can)_ run with a lot more power than Wi-Fi, and are on lower frequencies, so the range at which you'll detect them is significantly longer, which might make localised device counting less useable.
- gsich 8y agoRTL-SDR won't get you most LTE bands, 1800, 2100, 2600 MHz will be quite challenging.
- bigiain 8y agoIf you buy carefully you can usually get 1800 on a TV Tuner with the right chipset. You can get to 2.4GHz with a satellite downconverter if you haven't by then bought in enough to buy a (way) more expensive SDR.
- gsich 8y agoE400 goes to around 1.7 GHz, R820T to about 1.85 GHz, which doesn't cover the full LTE band, so yes it's pretty shit at the higher frequencies, 10$ won't get you anywhere there. But then you are not in the price range anymore.