RTK

The Certus Mini N and D internal GNSS receiver(s) supports RTK GNSS which uses correction data (RTCM messages) from a nearby base station to provide accuracy of up to 0.01 m in real time. An RTK system requires additional infrastructure equipment to generate and receive corrections data, and is not practical for all applications.

There are two different methods for receiving RTK corrections:

  • Network
  • Radio modem

For applications where Certus Mini can achieve internet access, network RTK corrections (NTRIP) are recommended.

For applications that are unable to access the internet, radio modems can be used to communicate between Certus Mini and the base station, see .

Network RTK Corrections (NTRIP)

NTRIP can be configured as follows:

  1. Using the Certus Mini Manager application, select NTRIP Client under the Tools menu.

Any of these NTRIP clients can connect to a network RTK service to stream RTK corrections to Certus Mini. This requires that the client is connected to the internet, and a valid subscription with a local network RTK service. Contact Support if you need assistance in setting up for network RTK corrections.

Radio Modem RTK Corrections

 

 

Trimble R4 Base Station

Trimble TDL 450L Radio Modem

Base station radio modem RTK corrections require both a base station and a radio modem receiver. The base station is set up at a fixed location and transmits corrections to the radio modem receiver that is connected to the mobile Certus Mini unit (the “rover”). The radio modem receiver and Certus Mini unit must remain within radio range of the base station to receive these corrections. The base station should be located no more than 50 km from the Certus Mini, and ideally closer. Advanced Navigation recommends contacting a local surveying company for assistance setting up a base station.

RTCM Messages

The following RTCM v3.3 messages are recommended for the internal GNSS receiver in Certus Mini.

Message Number Description
1005 Stationary RTK reference station ARP
1006 Stationary RTK reference station ARP with antenna height
1007
 Antenna descriptor
1033 Receiver and antenna description
1074 GPS MSM4
1075 GPS MSM5
1077 GPS MSM7
1084 GLONASS MSM4
1085 GLONASS MSM5
1087 GLONASS MSM7
1094 Galileo MSM4
1095 Galileo MSM5
1097 Galileo MSM7
1124 BeiDou MSM4
1125 BeiDou MSM5
1127 BeiDou MSM7
1230 GLONASS code-phase biases
4072.0 Reference station PVT
1002 Deprecated
(supported but not recommended)
1004 Deprecated
(supported but not recommended)
1008 Deprecated
(supported but not recommended)
1010 Deprecated
(supported but not recommended)
1012 Deprecated
(supported but not recommended)
1019 Deprecated
(supported but not recommended)
1020 Deprecated
(supported but not recommended)
1044 Deprecated
(supported but not recommended)
1045 Deprecated
(supported but not recommended)

Recommended RTCM v3.3 messages