RTK using NTRIP - setup assistance please

Ground Control Software Mission Planner
1

I am not getting a GPS RTK status and ask if anyone can help.

I have MP 1.3.46 running on a Surface Pro 3 and connected via usb to a Pixhawk with an M8N GPS/compass. Nothing else is connected except the arm switch and buzzer.

I have used RTK/GPS Inject to connect to a commercial base station and appear to be receiving RTCM messages. When I connect MP to the Pixhawk the GPS status begins as ‘3D Fix’ and then ‘DGPS’. But it does not report ‘3D rtk’.

This is all new to me and i’m not sure if this is supposed to work as I hope. Any thoughts would be appreciated.Thanks.

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2

your ntrip base looks good. one thing I need to confirm with you though is you said M8N. the m8n does not support RTK.
only the M8P/here+

3

Hi Michael,

The new MP page is also o bit confusing to me as it does not show the accuracy of the base, whether the survey is valid or in progress (which the previous version of MP shows). May I ask how do we know the status of base in the new version?

Thanks!

4

Thanks Michael,

Yes, I am using an M8N. This is a new area for me so I did a bit of reading and decided to get some cheap hardware to see how it all works.

If I understand correctly (and there is every chance I don’t!), the M8N won’t work because it does not output the raw GPS signals and therefore the RTCM corrections cannot be applied?

I read here (https://rtklibexplorer.wordpress.com/2016/11/25/selecting-a-gps-receiver-m8n-vs-m8t) that it might be possible to configure the M8N to do this. If I am able to get the M8N to output raw GPS data, is this all I need to achieve RTK in MP, or are there other things that would trip me up?

5

are you using a m8p?
if not then this information is not provided and therefore not shown.

if you are using a m8p, then it will display the numbers when you have m8p autoconfig enabled.

6

the m8n you might be able to use with rtklib etc. but not by itself. it does not support native rtk. only via a 3rd party application.

ie the emlid reach uses a m8t with a intel Edison to do rtk.

7

Hi Michael, @Michael_Oborne

what numbers do you refer to?
We do have Here+ RTK set and are able to do NTRIP and get RTK fix but see no numbers about accuracy and global position of the base. See the picture.

Thanks in advance.

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8

you are using ntrip. so you will never see accuracy numbers from the base. The accuracy numbers only work if you are using a here+ as a base station.

9

Ok thanks, then we are assuming the position provided is accurate close to a few centimeters.
I still think would be great to know that position but it is true that if we don’t have a good GPS to compare with then what’s the point?
I understand, thanks Michael.

Regards!