1
$\begingroup$

We want to create robot that will localize itself by the signals of wifi routers. Which sensors should we buy to detect strength of 3 WiFi signal? Which of following is necessary for us? http://www.dfrobot.com/index.php?route=product/category&path=45_80 or can be any other more suitable variants? We are using arduino as a platform.

$\endgroup$
  • 2
    $\begingroup$ Although not directly related to your question, localizing anything with just 3 WiFi routers is a terrible pain. Unless you have some very advanced filtering mechanism up your sleeve, this approach will not work. What can work more easily is to surround your target workspace with multiple routers, probably in a grid, and then log the RSSI signals for all the routers by moving your robot around the area. Train a suitable machine learning algo (ANN might work) in supervised mode to identify the coordinates of your bot, based on the array of RSSI signals. You'll need quite a few routers for this $\endgroup$ – metsburg Mar 10 '14 at 5:14
1
$\begingroup$

Any WiFi system should be able to report the signal strength (in dBm), but the question will be how quickly you need it to report values and how accurate a measurement you are looking for.

The main problem with what you're suggesting is that the relationship between signal strength and distance is not necessarily linear. Antennas produce an interference pattern which can make the strength change depending on your orientation to them.

antenna lobes

The second problem is that the signal strength can be affected by the environment: humidity, nearby metal, buildings, and even your body can affect the strength of the signal (if not directly, then through interference).

The only way to really do it is by heavily characterizing the wifi signals in the area you want to operate in and hoping that it doesn't change too much over time.

| improve this answer | |
$\endgroup$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.