How to fix observations with an excessive amount of cylce slips

I was mapping (flying) last Thursday (01/24/19) during a periode with a high kp index.
I could notice it because the uav was doing strange things when the rtk solution was lost (I first thought that it was a compass problem). Unfortunately I could not postpone the flight and cannot repeat it.

Is there any chance/best practice to rescue the observations?

Can you post the base and Rover ubx files?

Thx @wizprod,

yes, I can provide some of the base and the rover ubx files. The thing is so bad that I’m even missing 158 events where no solution at all is calculated.

base ubx

uav obs/nav

The appr. llh position of the base was: 54.435141433 13.197635948 38.9393

Is this from a fixed wing or ?

It is a hexacopter, numerous flights, flight speeds between 3 and 8 m/s. I try to reduce the post processing time by producing one single ubx file. The file contains 100, 60 an 30 m cross pattern flights.

Ah, ok, makes more sense.
Was about to ask you for the secret battery-technology for a keeping a UAV in the air for that long :stuck_out_tongue:

Secret is common reed leave based batteries:

And it is actually a reed stand I’m doing a survey of :wink:


That’s a tough nut. The data has sooo many cycle slips, I’m surprised it will give any fixed solutions at all.
Even precise orbits and clocks doesn’t help.
Do you have a picture of your Reach M+ (?) antenna setup ?
Was the base data collected using a Reach RS(+) ?

I agree that KP index go high, but especially on GLONASS they are not interferred at the same time, always, which I find wierd.

Edit: Looking at this Euref station 30 km away it has almost no cycleslips in the same timespan.
Was there heavy machinery operating near by or something similar?

The data was collected with first generation Reach receivers. The antenna setup is suboptimal but did work for more than 1.500 ha last year. I also think it is hard to believe that it is a setup problem when all differently mounted receivers have a problem. The problem is also less significant at the end of the day.

I have had a look at some observation files I have:

Original base obs file of the 24th of January:

An obs from the 26th of January at another place.

An obs from the 28th of January from the same place as the original data

An obs from the 31st of January from the same place as the original data

The kp-data does not really support my thesis with high kp-values beeing the source of the problem:


I hope that my units are not damaged but that I discovered some BND activity (our not so funny and not so intelligent intelligence service ;-)).

Or may be it was a temperature problem? Around 0°C might probably be too “much”?
There was no machinery near by. I don’t know whether any signals for ships etc. cause such interferences?

Or have you or has anyone experienced same problems during periods with high kp-index?

When I look at a lot of my observation files I could get the impression that my units are getting worse. I hope thta is only the winter depression… .

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