Multiple anchors

Hi all,

I was wondering if anybody has don a RTLS system using more than 4 anchors (say 10) and one tag.

of course for having the localization you need at least 3 anchors.

my idea is this:
let’s say i have a big room in wich i need to place 10 anchors and localize a single tag.
if the tag doesn’t reach the anchor it doesn’t go into the ranging and then poll another one.

i have seen there is the new Trek1000 kit (basically 4 EVB1000 with a different software) that allow up to 4 anchors and 7 tags.

my question is: why the trek allows only 4 tags? can i set more that 4?

thanks,
Fabrizio

TREK is just a simple demo of a TWR RTLS. The default system cannot be configured to have more than 4 anchors, however the source code is available so can be modified to handle other scenarios.

Hi Fabrizio,

I currently have a set up using custom hardware with 6 anchors and 1 tag, but I have enough anchors to go up to 16. There’s no reason you can’t have as many anchors as you want, you’re just limited on the amount of air time you have, so if you need high frequency localization you’ll only be able to have a limited amount of anchors and tags. For reference I currenlty do 10 Hz ranging with 1 tag and 6 anchors.

-Paul

Of course you can. As far as I remember, DEV_ID is 16 bit long, so you can reach up to 2^16 -2 Anchors (one address for tag and one for broadcast). In my system, single SDS-TWR takes 2ms (good balance between range and performance) which for 10Hz requirement of sampling ferquency allow you to reach 50 anchors :slight_smile:

Regards,
Bartosz