I am running some tests to determine the accuracy of the GPS receive time of a LoRa frame in the RAK 2245 sitting on top of the Raspberry Pi.
I am running two RPi’s each with a RAK 2245 with the GPS antenna. They are both running Chirpstack base 5.27.2 and sending their data to my Chirpstack server running in the cloud.
So I have two of these gateways running in the same house. The GPS has resolved the location of each gateway accurately, The way I am running this test is that I have one LoRa WAN sensor, that sends a frame every few seconds. I am then looking at the metadata of that in Chirpstack metadata.
As you can see, although I have anonymised some fields, there is a decent GPS location resolution but the timeSinceGPSEpoch is way out. It almost feels as if this field is not populated from a GPS timestamp at all, but just the regular system clock.
Does anyone have any advice or has anyone looked into this before?
Thanks for your time and interest.