Instructions for connection and use of the real time kinematic data (RTK)

I. REQUIREMENTS AND GENERAL INFORMATION

I. 1. Account of RTK uses input connection on Rover

- Enter the correct account of RTK name and password created on vngeonet.vn (Note that if your account has entered ntrip account information and ntrip password, this is the account name and password entered into the rover, to see this information on vngeonet.vn page, go to Account details > User information. Account name and password are sensitive to uppercase and lowercase characters)

- Account of RTK is still valid

- Not too many concurrent connections

- Use area has been licensed for use

I.2. Rover

- Has Wifi/3G/4G internet connection

- Support Ntrip connection

- Able to receive signals at signal reception intervals of 1 second or less

- Support receiving RTCM 3.x data, receiving full RTCM 1021, 1023, 1025 rectification packages (automatically receiving 7 conversion parameters, residuals and axis meridians, projection zones... from the VNGEONET network provided, See details of these rectification packages click here ).

I.3. General information connecting to the VNGEONET network

- Server IP (Host IP): 14.238.1.125 (or vngeonet.vn)

- Port: 2101 or 2102 or 2103 (see details of these ports click here )

- Account name and login password are the account of RTK mentioned in section I.1.

II. CONNECTION CHECK INSTRUCTIONS

During the process of supporting connection to the VNGEONET network, the main reason for not being able to connect is due to the user entering incorrect information such as: input wrong Host IP, wrong login name or password, 3G/4G Sim running out of data, or loose installation, rover outside of authorized region, Too many concurrent connections, cannot received full RTCM 1021-1027 correction... The following is a VNGEONET network video showing basic steps for users to self-check when unable to connect data to the VNGEONET network.

Instructional video

* Meaning of RTCM rectification packages 1021, 1023, 1025:

- If the used Rover does not receive all RTCM 1021, 1023, 1025 correction packages, the test results at the original landmark may vary by 3dm - 4dm and more.

- Currently, the VNGEONET network is sending the following RTCM v3.x data packets to the rover including: 1021, 1023, 1025 and 1029:

No	Code	Describe
1	1021	Includes 7 Helmert / Abridged Molodenski coordinate conversion parameters (WGS84 => VN2000)
2	1023	Residual model, represented by geographical coordinate grid on Ellipsoid
3	1025	Projection parameters, projection zones
4	1029	Unicode character string. Unicode character string messages serve to automatically notify Rover about connection or Server-related problems. Typical cases include: - Rover outside the designated area - Error connecting account - Access denied, due to too many concurrent connections - Access denied, due to too many simultaneous permission requests.
5	1033	Describes information about the Receiver and Antenna including serial number and firmware version

- The process of processing information of these packages on Rover when achieving FIX results is as follows:

+ Step 1: Use RTCM 1021 package to calculate 7 coordinate conversion parameters to BLH on VN2000 coordinate system.

+ Step 2: Use the results of step 1 and added the values in the RTCM 1023 package to get the results B'L' and h (height level).

+ Step 3: Use the B'L' result calculated in step 2 combined with RTCM 1025 package to calculate xy coordinates.

* Meaning of VNGEONET network ports:

- Port 2101 (VRS) network solution. Mountpoint names start as VRS...

- Port 2102 (iMAX) network solution. Mountpoint names start as iMAX...

- Port 2103 (SB) single base solution. The mountpoint name starts with SB

- Meaning of each mountpoint name:

+ The first part represents the measuring port (VRS or iMAX or SB) the next part after the dot '.' is the axial meridian and projection zone of the measurement results. (For example VRS.105M3: measured at port 2101, result on coordinate system VN2000 105 degree axis meridian, 3 degree projection zone, iMAX.105_45M3: measured at port 2102, result on coordinate system VN2000 105 degree 45 minute axis meridian, 3 degree projection... same for other mountpoints). When measuring, depending on the required measurement results on the axis meridian and projection zone, choose accordingly.

+ When used, priority is given to using 2 ports 2101 and 2102 because this is a stable, highly accurate network solution, overcoming the dependence on the distance between rover and base station (requiring rover to measure in the network area). .

+ Port 2103 is used in case the rover measures outside the network area (usually to locations adjacent to the sea and border...) or using 2 ports 2101 and 2102 does not achieve FIX results. This is a Single base solution so accuracy will be affected when the rover location is far from the base station.

+ Ports 2101 and 2102 are both network solutions but there will be differences as follows: Port 2101(VRS) has faster FIX speed but is not as reliable as 2102(iMAX), port 2102 FIX speed will be slower 2101, but once FIXed, the value will be more reliable than port 2101. Regarding the measurement results at ports 2101 and 2102 under good measurement conditions, the values are equivalent.

Image of Network measurement locations (2101, 2102) within the blue border area, Single Base 2103 is outside the blue border area