Basic Question

[color=#111111][size=small][font=Tahoma, sans-serif]Hello everyone,[/font][/size][/color]
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[color=#111111][size=small][font=Tahoma, sans-serif]I’m interested in a decaWave system, including some anchor modules to check a certain “safety area” near a machine. That would include multiple tags, which have to be checked by their distance, but not to be distinguished. So any tag in the “safety area” would cause an alarm or something.[/font][/size][/color]
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[color=#111111][size=small][font=Tahoma, sans-serif]Is this possible with any decaWave system?[/font][/size][/color]
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[color=#111111][size=small][font=Tahoma, sans-serif]Thanks a lot in advance![/font][/size][/color]
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[color=#111111][size=small][font=Tahoma, sans-serif]Kind regards,[/font][/size][/color]
[color=#111111][size=small][font=Tahoma, sans-serif]Ernst[/font][/size][/color]

This sounds like the “safety bubble” use case. If the locations of the tags are not important, you can simply place an anchor at the machine and let it do two-way-ranging with the tags. If a measured distance is lower than a preset threshold, then a alarm will be triggered. We have made somethings similar for forklift.

Thank you for your answer!

Is the number of tags in this case limited?

Hey Ernst,

Tags are always limited if you just do twr and have no controle. You can have a look at the Decawave user manual p 211 for a guidance in how much you can send. These numbers are for TDOA. So for TWR you can divide those by 4 for a rough estimate.
If you switch to a more controlled manner like slotted ALOHA or TDMA you can increase the number of tags drastically. But they are harder to implement.

Kind regards,