How to Calculate Distance from the RSSI value

1

Dear All,

I use CC2531 USB sniffer as coordinator and have have some Zigbee End device.
I can control ON/OFF ZED by CC2531 USB sniffer and zigbee2mqtt.
(mosquitto_pub -h localhost -t zigbee2mqtt/0x00124b00071a0271/set -m “ON”)
I need calculate distance from Coordinator (CC2531 USB sniffer) to Zigbee End Device.
Can you help me?

Thanks and Best regards,

Chuc.Le

2

The short version is, you can’t.

The long version is that the RSSI value is influenced by the materials in the way, so a thin piece of metal will have a bigger impact that a few feet of air. You can easily have a situation where device A is physically further away, but you have a stronger signal.

3

Dear Tinkerer,

Could you help me with long version (how to we have it) and how to calculate distance from coordinator to device into this version.
Addition, my Coordinator and ZED is in the air and without obstructions.

Thank you,

Chuc.Le

4

The short answer is, not really.

I don’t know the maths sufficiently, or know the details of the devices. The signal strength will be influenced by the antenna on both ends, the angles of the devices relative to each other, and more.

You’re not quite asking how long a piece of string is, but what you’re asking is nowhere near as simple as you think it is.