How much does does 3D Antenna help with RSSI?

  • Hello!

    I am implementing room level presence detection with Espresence ( I got some generic WROOM-32 modules on amazon but i'm noticing the RSSI is insanely low for the BLE monitoring! At 1 meter the RSSI of my phone and smart watch are both in the -80 to -85 range, and thats not even at the lowest transmission power!

    I am considering purchasing something like the M5Stamp C3 Mate since it seems to have a better antenna but i'm wondering how much he 3d antenna helps with RSSI for BLE advertisement monitoring. Can anyone give me some insight on this>?

  • There is a rule in the RF world: "the best amplifier is a good antenna". You can get a higher antenna gain if the directional pattern is narrow. A good example for a very narow pattern is a satellite-tv dish or line-of-sight communication devices that need to be exact aligned to get a good signal. The opposite is a omnidirectional antenna in a WiFi device where the signal strenght is more or less the same all around the device. there are many different antenna designs for different pattern and different applications on the market.
    It may help to study the datasheet of the 3D antenna, which is a PRO-OB-440 in this case, to decide if the pattern works for your application and how much gain you earn. As far as I see the PRO-OB-440 is not bad for its size but as every antenna, it has to follow the laws of science and cannot do witchcraft.

  • @holofloh You weren't lying... Great results with M5Stamp C3

    If anyone comes across this thread who are also disappointed by their generic WROOM-32 modules. Just buy the M5Stamp C3, they aren't much more (actually the same price when compared to the generic WROOM-32 modules on amazon!!) and they made my phone RSSI go from -80ish to -60 at the same distance and lower transmission power! My Watch transmission power i kept the same but it went from -85 to -60ish as well! That's a truly insane gain for such a small little thing. The generic modules trace antenna just doesn't cut it!

    Plus they have a fun RGB LED you can configure!

    I'm convinced, I'm going full M5Stamp!