Large Mesh Network Not Receiving All Messages

XBee & XBee Gateway XBee - DigiMesh
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1

I’m trying to set up a large mesh network system with DM2.4 modules. Currently I’m conducting a receiving bench test with 10 nodes, but would like to eventually expand to 50.

I have 10 individual broadcast nodes on Arduino, sending a 20 byte message at 5Hz in Transparent Mode. In this test I’m receiving and analyzing the data on a separate receiving module connected to a computer. Over the course of 10 seconds I expected to receive around 50 messages from each node, but this was not the case. I was only able to receive between 20-30 messages on some of the nodes, which is a 50~60% receiving rate.

On a separate test I performed with only 1 node broadcasting the same message at 200Hz, and all messages were received. This seems to indicate that the additional nodes in the mesh network is preventing me from receiving all the messages.

I’m wondering if this has something to do with network routing settings in the Xbee firmware. Is there a set of settings that you would recommend trying?

What happens when there are multiple packets being received at the same time? Since all broadcasting nodes are sending independently at the same frequency.

2

Broadcast consumes high amount of data traffic. Every packet is re-transmitted 4 times (MT+1, default MT=3). I guess that’s reason for drop in throughput in your setup.

By decreasing MT=0, you can make a big difference in network traffic and should drastically improve situation.

3

It doesn’t look like XCTU allows me to set MT to 0. Whenever I have MT = 0 and write the settings, it always revert back to whatever non-zero value it was before after I refresh the settings.

4

NVM my XCTU wasn’t updated to the latest version.