Community Forum

Events in NTRIP mode

(Krzysztof Stulka) #1


I put Reach on my quad and I set it up to work in NTRIP mode. I got around 16 sat and corrections for them (AR999). The hot shoe is connected to RS. Autopilot triggers the camera. How can I get events from RS? I send NMEA do Pixhawk but it logs the coordinates with 7 decimals digits (RS saves with 8 digits).


(Tatiana Andreeva) #3

Hi @kstulka,

Had you been recording raw data log during the flight?

You need to download the log from Reach M+ and post-process it using the log from your NTRIP service.

In the result of post-processing, you’ll get *event.pos file containing events.

(Krzysztof Stulka) #4

I postprocessed the data and I noticed a shift between ntrip and PPK data. I took XYZ from base file and typed into rtklib proc.
Why there is such difference (around 30cm)?

RED - Ntrip data (drone track)
Yellow - PPK

(Christian Grüner) #5

The Base coordinate from the NTRIP and the CORS(or own base?) aren’t identical.

(Krzysztof Stulka) #6

I was using only one Reach (mounted at drone). The corrections were coming from national service by NTRIP.

I was logging *.ubx, *.LLH, RTCM3 (from NTRIP from VRS).

I converted RTCM3 to *.obs and I used that as base. I opened that obs file and copy these coordinates ( xyz) to rtklib .

Is this procedure correct ?

(Tatiana Andreeva) #7

Hi @kstulka,

May I ask you to share these logs?

Could you please also download the corresponding RINEX log from NTRIP service you use and post it here?

(Krzysztof Stulka) #8

base_201902121024_RTCM3.zip (64.0 KB)
raw_201902121024_UBX.zip (563.6 KB)
solution_201902121024_LLH.zip (29.3 KB)

please find enclosed.

(Tatiana Andreeva) #9


I’ll check them and get back to you.

(Tatiana Andreeva) #10

Hi @kstulka,

According to RINEX standard, base coordinates in RINEX header differs from the real base position.

Could you please ask your NTRIP provider for station coordinates? Then you need to enter it manually in RTKPost options.

(Krzysztof Stulka) #11

It was VRS. There was nor real base postition. I thought I could use the the VRS base position, but It seems it is not possible.

(Tatiana Andreeva) #12

Hi @kstulka,

It seems, in that case, RTK result is more accurate than PPK.
Is there any CORS station to use RINEX log from it for processing VRS base station position?