60 modules communication test

A project log for Green Detect

Wireless Sensor Network Platform (WSN) , for enviromental monitoring

Sergio GhirardelliSergio Ghirardelli 07/07/2022 at 14:460 Comments

We all know that theory is often not reflected in practice.

Could I submit a sensor network project, claiming a network of 60 sensors without being sure it worked?

No! I had to be sure, so I decided to test if my theoretical calculation was correct.

The following video shows the tests carried out.

Why 60 modules limit?

Green detect wireless sensor network uses ESP-NOW protocol.

The first ESP-NOW technology limitation is that the total number of peer devices should be less than 20.

How did I exceed this limit?

I simply created a chain network, where each device communicates with 2 other devices the one from which it receives the packets and the one to which to send the processed packets.

Basically I created many small networks, exceeding the limit of 20 devices.

Why can Green Detect network include a maximum of 60 devices?

Because the ESP-NOW technology has another limitation: up to 250-byte payload can be carried.

And since I have foreseen 4 bytes of transmission per sensor, I can use a maximum of 60 sensors (60x4 = 240 bytes)