Not getting PointPerfect corrections to SW Maps from RTK ESP32 Boards

GPS/GNSS Development Boards
1

I have the following components:

SparkFun GPS-RTK-SMA board https://www.sparkfun.com/products/16481

ESP32 board https://www.sparkfun.com/products/20168

Antenna https://www.sparkfun.com/products/17751

components.jpg
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When I run “Arduino Example 18: PointPerfect Client”

https://learn.sparkfun.com/tutorials/ge … ect-client

I get a RTK fix with a horizontal accuracy of less than 2cm.

example18.jpg
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When I run U-center with the PointPerfect MQTT client I get 3D/DGNSS/FIXED mode.

u-center.jpg
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When I connect my android phone to the RTK board with a USB cable and run SW Maps, I select USB Serial GNSS. I never get better than a DGPS fix with 10 feet of Lat Long error.

What am I missing?

Thanks,

Bruce

2

My guess is that it’s using your phone’s regular GPS instead of an RTCM feed source (like pointperfect, or UNAVCO)

On the android phone: are you using an RTCM client like NTRIP to feed RTK data? https://learn.sparkfun.com/tutorials/gp … ion-source

Finally, there are more links/info for the PP side of things here https://developer.thingstream.io/guides … xnnov43qw4

3

I connect my phone to the RTK board with a USB cable and select “USB Serial GNSS” in SW Maps. This is what the connection looks like.

SW_Maps2.jpg
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My PointPerfect service is providing corrections using the SPARTN open data format and the MQTT messaging protocol. So I am not using a NTRIP client.

I was hoping that the SparkFun u-blox GNSS v3 “Arduino Example 18: PointPerfect Client” running on the ESP32 would send the corrections to the RTK board.

https://learn.sparkfun.com/tutorials/ge … ect-client

From the comments at the top of example 18:

This example shows how to obtain SPARTN data from a PointPerfect Broker over WiFi

and push it over I2C to a ZED-F9x.

It’s confusing, but the Arduino is acting as a ‘client’ to the PointPerfect SSR correction service.

You have to edit the header file of the example 18 sketch to include all of your PointPerfect credentials along with the ID and password of the mobile hotspot Wi-Fi connection on your phone. Then the script pulls the correction data down from the internet and feeds it to the RTK board.

I was hoping that plugging the phone into the RTK board would automatically run the ESP32 script and feed the corrections to the RTK board. I don’t think that is happening. It might require a different but similar script.

4

Added some drop-thru behaviour so it connects without any keystrokes

https://portal.u-blox.com/s/question/0D … -rtk-board