we have tried a Lorawan Network with Catenna 44550 node and Multitech Gateway.
we can able to achieve data transmission for 15 minutes, when the gateway is kept in 500mts to the 1000mts range.
specifications are below
1.Band = IN865.
2.Frequencies Used by Node and Gateway = 865.0625, 865.4025, 865.985.
3.Coding Rate = 4/5.
4.Modulation = LORA.
5.Data Rate = SF12BW125.
6.payload = 27(include lorawan header)
Using the above specifications. we tried transmissions for 3Km, but the output we got is uneven data transmission with non-regular interval.
we have also checked TTN-fair policy, using spreading factor, bandwidth, payload length.
we have calculated duty cycle and time on air using the above data.
Suspecting that we have exceeded the fair usage limit, we changed the frequency to every one hour.
Using the above calculator we found that we could send 15 packets/day at data_rate of SF12BW125. we are sending data on three channels
865.0625, 865.4025, 865.985. so we have a total budget of 3*15 packets per day and at a rate of sending data every one hour we will be much below the fair usage limit.
However even with these reduced frequency we are loosing several packets every few hours as you can see below
Date time Battery Volt Water Level |13/05/2019, 15:53:24|4.2412109375|26.7617352089704| |13/05/2019, 14:53:18|4.24755859375|26.7649417329256| |13/05/2019, 12:53:04|4.2412109375|26.7697515188583| |13/05/2019, 11:52:58|4.228271484375|26.7694308664628| |13/05/2019, 10:52:51|4.221923828125|26.7796917431193| |13/05/2019, 09:52:44|4.208984375|26.763979775739| |13/05/2019, 05:52:18|4.202392578125|26.7614145565749| |13/05/2019, 04:52:12|4.208984375|26.7598112945973| |13/05/2019, 02:52:00|4.208984375|26.7614145565749| |13/05/2019, 01:51:53|4.21533203125|26.7614145565749| |13/05/2019, 00:51:46|4.221923828125|26.7630178185525|
How do we narrow down to the real cause of lost packets? is it due to exceeding limits or due to range issue or is it because the node is sending on wrong frequency for those lost packets.
right now without clear way to debug, we are unable to solve this riddle.