Connectivity to TTN isn't constant in isolated forest region


I want to use a LtAP lr8 LTE kit from Mikrotik in an isolated forest region. Internet is usually available via LTE, but reception sometimes breaks down and this produces data gaps. Maybe also the lora connection isn’t stable because the distance between the gateway and the devices is about more than 1 km and there some of the devices are in local sinks. I use an external lora antenna.

My questions:
Is it possible to store the transferred data from lora on an USB stick to close the data gaps? The LtAP lr8 LTE kit has an USB port. What i must do to use the memory capacity of the stick to avoid data gaps.

Next i test to use an external LTE antenna to improve the internet connection.

An other question about the lora connection:
Is there any device which take the lora signal from the sorrounding devices and emit the signal amplified and repetetive (or only repetitive from an other position to improve the chance to transmit the signal to the gateway) to the gateway and reverse? Is there any possibility to improve and secure the lora connection between the gateway and the devices?


If you search the forum you will see both data store and replay and LoRa/LoRaWAN relay/repeater discussions come up regularly and have been much discussed and reviewed. TL::DR Neither really practical.

Store and replay presents a fundamental problem in that once system ‘connected’ again and new data starts arriving at NS earlier messages that get replayed would be rejected as they would have a lower FCount and would be seen by the NS as a replay attack. You could turn off FCount validation but that is not recommended and is a security risk …'cause replay attacks! Or you could also store any new messages until old data has been replayed…but that would further delay new messages, and if some messages (old or new) require a response or trigger NS responses and downlinks then it all gets very messy very quickly!

Repeater have also been discussed - with one of the originators of LoRa/LoRaWAN even pitching a potential solution at a TTN conf some 4 years back (GIYF), but so far no viable commercial offerings have emerged into the market. Again there are fundamental issues such as timing and network latency and also end device addressing issues (esp where repeater handles multiple end points)…basically best option is densify the network and deploy additional, closer GWs if possible!

There are ways and means - the best one to store uplinks, either individual or aggregated, on the device, and if there is a gap, send a request to send the missing data - raw or summarised (with timestamps). Sending decimated data quickly fills in the gaps and if you need the individual data points, they can follow on after.

Another option is LoRa (NOT LoRaWAN) to relay data point to point or mesh and then on to a LoRa (NOT LoRaWAN) to LTE.

A repeater is a whole bag of complication - it needs to take the uplink and replay it exactly as if it came from the original device - which is effectively as LoRaWAN to LoRa posing as LoRaWAN type mess.

There are some things you can do. However, they might not be suitable for your application.

  1. Realise that LoRaWAN is not a reliable network and modify your application accordingly. This is probably the most important step. For example, if you need very reliable communication but don’t care about latency, you’re better off with logging data locally and uploading it using LTE once a week.
  2. Use confirmed messages for your device. This will give reasonable reliability. However, please note that TTN restricts you to 10 messages sent to a device per day, so it’s best to use confirmed messages for infrequent updates. You need to be smart about it and think about your application. For example, if you have some event detector, use unconfirmed messages for every event and confirmed messages every 6 hours to transmit the event counter. That way, even if an event detection message does not reach the network, you know how many events were detected in a 6-hour window, which might be sufficient for monitoring traffic or animals if it doesn’t happen too often.
  3. Use better antennas (less return loss, maybe even higher directivity) to increase the chance of your message reaching the gateway. Please note that you need to adjust the transmission power accordingly.
  4. Use a higher spreading factor
  5. Install another gateway somewhere else. It is unlikely that both gateways suffer from loss of LTE connectivity at the same time.
  6. Place your device somewhere else with better coverage. While this may not be possible all the time, it is an option when you want to monitor something in some place, but don’t care exactly about where the device is placed. A few hundred meters can make the difference between no network coverage and excellent coverage. Also consider using long cables for sensors and placing the device somewhere where there’s better reception, e.g. most likely higher up.
  7. Use coverage simulation tools, e.g. Radio Mobile Online to plan antennas and gateway locations

LoRaWAN Repeaters are infeasible, mostly due to duty cycle restrictions and due to added latency. You need to be able to send messages back to the device and there is not too much time for that, just about 5 seconds after the device has sent the message with TTN.