Wi-Fi triangulation

Notecard API
1

Hi,
I’m interested in Wi-Fi triangulation using the Wi-Fi notecard. I’m trying to grasp it, and a question a rise. For my understand the Wi-Fi notecard already has the triangulation enable. So I just need to send the Wi-Fi access point (AP) scan related to the AT+CWLAP command. At an movement detected it the latitude and longitude is displayed in an json format. What I’m not grasp is how the latitude and longitude are determined, if with RSSI only the distance to the Wi-Fi AP can be calculated ?

Thank you very much,
Mariana

2

Hi Mariana and welcome to the Blues Wireless community!

As noted here, when using the Wi-Fi Notecard triangulation is enabled by default, so you don’t have to send AP information to the Notecard.

In terms of how it actually works, there is a good article here on that subject:

1 Like
3

Rob,

Thanks for the write-up at Indoor Asset Tracking using Wi-Fi Triangulation - Hackster.io. Very nice. I was looking into triangulation for the new bGeigieZen (https;//bgeigiezen.safecast.org) to get better positing of the device in areas where there is not so good GPS. Specially, reflections in buildings would get us not accurate positions. Even in Japan with GNSS systems, we still do have a lot of reflections. Wi-Fi triangulation would be great if we can get it working correct.

For Ray, I have heard that the way Blues uses Wi-Fi triangulation is that Blues uses a paid subscription for the accessing a database. Are there also options for a not paid service that you would recommend?

Regards and happy holidays,
Rob Oudendijk

4

Hi @robouden - I’m not aware of any free services that allow for this functionality. I believe Apple/Google sell this data, so it’s unlikely that 3rd parties would turn around and make it available for free!

1 Like
5

@RobLauer

Thanks for the reply. I will check a bit more.
Love to have the Wi-Fi triangulation working for free (Open Source low budget projects)

Regards,
Rob Oudendijk