Building RTK base using simpleRTK2B

Q&A forumCategory: QuestionsBuilding RTK base using simpleRTK2B
mw2.parkis asked 4 months ago

HI ArduSimple team,
I have 1 simpleRTK2B for my application. I would now build an RTK base with Long Range radio. Would you please let me know the hardware setup and the additional hardware I need. Is there any tutorial available?

Ardusimple Staff replied 4 months ago

You need:
1x rover LR
1x radio LR for your existing board:

LR radios are pre-configured, you can load our configuration files to base and rover:

12 Answers
mw2.parkis answered 4 months ago

HI, the setup of rover LR is clear now.
About the Base, I think I need to connect the simpleRTK2B with a computer connecting to a SatRef NTRIP server and running U center with NTRIP data stream via the internet. Would you please confirm?
Is it possible to set up a stand-alone base, what additional hardware or configuration needed?

Ardusimple Staff replied 4 months ago

Your assumption is correct.
Alternatively you can get our WiFi NTRIP Master and then it would be standalone once you have configured the WiFi parameters.

mw2.parkis answered 3 weeks ago

Hi ArduSimple team,
I have now 2 SImpleRTK2b and 2 LR.
1 pair has been downloaded with firmware version: UBX_F9_100_HPG_113_ZED_F9P and simpleRTK2B_FW113_Base-00 , 
and another pair has the same firmware and simpleRTK2B_FW113_Rover_1Hz-00 configuration.
According to the post,, I have checked the UBX-NAV-PVT from BASE and 
the UBX-MON-MSGPP from Rover, but not signal.
Please find the Message of UBX-NAV-PVT as:
Param Value Units
GPS Time Tag 275294.000 [s]
UTC Date and Time 22/ 7/ 2020 04:27:56 -000376071
UTC Date and Time Confirmation Status Date: CONFIRMED, Time: CONFIRMED
UTC Time Accuracy 22 [ns]
Position Fix Type TIME
Fix Flags FixOK DGNSS
PSM state n/a
Position Latitude, Longitude, Height, MSL xx.3495196, xxx.0613384, 16.3, 18.4 [deg,deg,m,m]
Invalid Position Latitude, Longitude, Height, MSL No
Position Accuracy Estimate Horizontal, Vertical 1.2, 0.9 [m,m]
Velocity North, East, Down 0.000, 0.000, 0.000 [m/s,m/s,m/s]
Velocity, Heading Accuracy Estimate 0.010, 162.1 [m/s,deg]
Speed over Ground 0.000 [m/s]
Heading of Motion, Heading of Vehicle 0.0, n/a [deg,deg]
Magnetic Declination, Declination Accuracy Estimate n/a, n/a [deg,deg]
PDOP 99.99
#SVs Used 27
Carrier Range Status Not used
No message from UBX-Mon-MSGPP.
Would you please let me know which if the BASE has transmitted the RTCM signal or there is issue on the ROVER?
Best Regards,

clive1 replied 3 weeks ago

Should be able to use the UBX-MON-IO / COMMS / TXBUF messages to see the state of things on the BASE side. Check the messages enabled via UBX-CFG-MSG
Look at similar and UBX-RXM-RTCM on the ROVER side.
Check the radio baud rates, and point-to-point comms outside the ArduSimple board context.

mw2.parkis answered 3 weeks ago

Hi ArduSimple team,
I try the UBX-MON-IO/COMMS/TXBUF. They show there are data and transmitting through uART2.
But the UBX-RXM-RTCM is empty.
Is there any test mode to verify the RF link? 
As suggested to check the Baud rate, it is 115200 in TX UART2 and it is UART1 enabled in Rover, which is 38400. I am using the configuration file, simpleRTK2B_FW113_Rover_1Hz-00.
I try increasing the baud rate to 115200, but it is the same.
Would you please comment?
Best Regards,

Ardusimple Staff replied 3 weeks ago

Hi mw2.parkis,
I think we need to go one step back, the configurations you describe from the configuration files don’t match with what they should be.
– Are you storing into flash memory the configuration after sending them? (UBX-CFG-CFG).
– The base station cannot be in DGNSS mode, this means you are sending corrections or have SBAS enabled which is disabled in our configuration files.

mw2.parkis answered 3 weeks ago

Hi Ardusimple,
Thanks for your reply. I use the UBX-CFG-CFG to send the configuration to flash memory. 
I think it may due to the ‘sending corrections’. As the NTRIP Client is selected. 
Shall I input the Base position into the ‘Use manual position’ option, which is included in NTRIP client settings?
And what will be the FIX Mode when it is operating in BASE?
Best Regards,

Ardusimple Staff replied 2 weeks ago

Hi mw2,
If you have access to an NTRIP caster to calibrate your base station, connect as rover to this NTRIP caster and wait the receiver to get to RTK FIX. Copy this position and set it via TMODE3 as Fixed position. Now remove the connection to NTRIP caster.

When operating as base FIX type should be “TIME”, and only appears when UBX-NAV-PVT message is enabled.

mw2.parkis answered 2 weeks ago

Hi Ardusimple,
Thanks for your input. I follow your suggestion and the TIME fixed type is received.
There is no output from TX2. I removed the two XBEE LR boards.
Uart1 is used as the output and I can measure the output data. The TX1 is connected to RX1 of ROVER, the “fixed type” became 3D/DGNSS.
 I have the 5v_out connected to the IOREF. Would you tell me,

  1. how to send data from TX1 to XBEE RX? or
  2. how to check the problem of UART2 output?

Best Regards,

Ardusimple Staff replied 2 weeks ago

TX1,RX1,TX2,RX2 pins need to be enabled with IOREF.
UART2 pins of ZED-F9P are internally connected directly to the XBee socket.