We have 4 Emlid Reach-RX devices in our lab. We use them with the Flepos RTK-service in Flanders.
We constantly have problems with the stability of the app to receive RTK corrections: when we start the app, it does not connect to the Flepos service. We were in contact with them and they indeed see no connection attempts.
However, restarting the app (on Android: killing it by swiping to the top and restarting) does wonders. After a restart, the app immediately connects to the NTRIP service, receives corrections and finds a fix.
This looks very similar to the case below (which was closed, so I couldn’t reply).
Good morning, finally, other users are starting to notice this bug. Emlid engineers do not acknowledge this bug; they claim the problem lies with the smartphone. However, I have tested it on at least three different devices, and the result is always the same. If you thoroughly test Emlid solutions as I have, you will realize that the NTRIP protocol is not optimized to work with low bandwidths like 2G; it doesn’t function with less than 70Kbps, which is a problem because in areas with poor mobile data coverage, it is not possible to work. Fortunately, I can use the Lefebure NTRIP Client as an auxiliary. I turn off corrections from the Emlid Flow app and use the Lefebure NTRIP Client, which works even with internet speeds as low as 15Kbps.
Another very uncomfortable situation is the absence of correction age at the top of the screen next to the satellites. For those working exclusively with the NTRIP protocol from an internet server, correction age is crucial. Another suggestion is to only allow collecting points with a maximum correction age that the user could define, somewhat similar to the timer already in place for collecting points. I am looking forward to the implementation of these features, which will undoubtedly make your app a better and more robust product. Thank you.
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I don’t think the bandwidth is a problem in our case.
In the tests we did, our smartphones had a perfect 4G connection.
It’s not related to the smartphone type, because we encountered the issue with more than ten different devices (students during their lab sessions).
Yes, these are two distinct issues. The problem of correction loss without quick recovery, requiring an app restart, is an issue that occurs regardless of internet speed, even with a 4G connection. If the app loses corrections for any reason, it should attempt to recover them at intervals of no more than 3 seconds, but it takes about 1 or 2 minutes to recover. The workaround is to restart the app. The second issue I encountered is the poorly optimized NTRIP algorithm in the Emlid Flow app. After extensive testing, I found that if the bandwidth is less than 70kbps, the app doesn’t receive corrections. At first glance, this might seem like a low requirement, but the NTRIP protocol consumes an average of 9.6 kbps. Requiring a minimum of 70 kbps means it needs to consume 7 times more mobile data than the protocol would need to function. This makes a significant difference for work in isolated areas with weak internet signals. Fortunately, I have a solution to work in these conditions, which is to use the free software Lefebure NTRIP Client. It receives RTK corrections with very little bandwidth, replacing the Emlid Flow app’s correction reception. This situation is somewhat embarrassing for Emlid…
Apologies for the radio silence here.
We’ve received similar reports from some of our users, and our devs are already investigating this. I’ll let you know once we find a fix for this.
Also, want to add that we were in touch with @sara.aguiar via email regarding the same issue. If anyone has similar issues, please don’t hesitate to write us to support@emlid.com, or create a new thread in the forum.