So me and my dad are trying to catch would be thieves and also someone leaving behind alcohol bottles. At his storage business the cameras don't reach to these spots.

Without being too invasive I want to sense bluetooth and/or wifi signals of relatively close phones sort of like a pax counter. This is in lue of using a pir sensor which I have always found finicky and I want to make use of the esp32' cam's wifi/ble chip.

So to start I researched for the past few days or week. I found that most phones don't use ble so maybe that is out. I also found that the esp32 cam is a bit finicky and I'm not sure if it is compatible with other code I have found.

One time I was able to get the light to come on when my phone was near using code I found for the esp32.

Any help or direction would be nice

Edit: I understand this sounds weird but mostly I would just like to get proximity of bluetooth or wifi to trigger an event. The device is powered by battery and I understand not everyone carrys phones.

  • Sniffing for wifi request probes could be an option. Knowing the networks a person was connected to can even be sufficient to identify or at least recognise different persons. I have absolutely no idea if that's possible on an esp32. The most difficult thing when doing this on a raspberry pi is finding a network adapter that supports monitor mode and I don't actually know whether the esp's interface supports that or not.
    – Sim Son
    Jun 21 '19 at 2:08
  • "I was able to get the light to come on when my phone was near" - how did you do this? Was your phone somehoe connected before or was it incognito like a stranger's would be?
    – Sim Son
    Jun 21 '19 at 2:10
  • incognito. but looking back it is possible it was responding to other BLE devices near by. I would bring the phone close sometimes the light would change. sometimes it wouldnt. It was very strange. The esp32 supports monitor mode its just I havent found any code that would compare RSSI strength of nearby devices. Or if thats even possible? Jun 21 '19 at 7:49

Detecting a phone could be easily done by capturing WiFi probe requests which are sent by phones having at least one saved WiFi network. Note that such requests alone are often enough to identify the person, if their home WiFi SSID is set to something like "Davids_wifi".

Software-wise, this would be much easier to do on Linux (think Raspberry Pi or a similar device) which already have all the network sniffing software like tcpdump, which you would otherwise have to find or implement on ESP32.

I'm leaving out the legal implications of what you're trying to do as I don't know what country you are in, but bear in mind that hidden surveillance may be illegal in some cases.

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