[StabiloRose] Concerns about WiFi

After my little post of yesterday, I tried to figure out if I was right, if the LED strips really blocks WiFi waves. I used old LED strips from a previous ROSE project and surround my phone with them. After many tries, the phone was still connected to the school network.

I see a few explanations:

1. I was wrong, the strips are not blocking WiFi waves. Everything is perfect, we don’t have to use an external antenna. But I don’t think that’s correct.

2. My phone is a Moto G 4G. I tried to find the position of its WiFi antenna, but found nothing interesting. It may be located in a corner, and the strips haven’t had a big influence on it.

3. Android is trapping me, saying he is always connected whereas it is not. He might say he is disconnected only after a certain number of reconnection failures.

Anyway, nothing can be really sure about our sphere at this time. Fortunately, the WiFi module can be connected to two external antennas. And we can switch between them. This gives us the liberty to put an internal antenna and a connector.

4 comments to [StabiloRose] Concerns about WiFi

  • Can you upload pictures of your test?
    Did you solder the strips grounds together?
    Can you stream a long YouTube video while the phone is in the sphere?

  • Alyx

    Your led strip is not really a faraday cage, since it is not a continuous plane but has big gaps between parallel strips. You will probably have some attenuation, maybe reduce your range by a factor of 2, but it will probably be ok for your needs.

  • clestrelin

    @Drix, it was only a quick try. I can send pictures but it’s only a phone surrounded with strips like a roasting join. The grounds were not connected together. I should retry with this configuration. In fact, we don’t have our ball yet. We are stuck at the components choice, schematic and routing step. The ball will come. I’ll post the results of new experiments.

    @Alyx, thank you for your help. Actually the wavelength of WiFi waves (2.4GHz with our module) are about 125 millimeters long. Our strips will be much closer, one or two centimeters at most. I’m not sure the signal could be still treated after this attenuation.

  • My last magnetostatics classes were 10 years ago so I might be wrong but I think you need to connect all the conductive elements to make a Faraday cage, the grounds should work.
    Anyway, a dirty hack picture is always appreciated 😉
    Feel free to let us know (in another post) where you’re stuck, we might have suggestions…