Network Real Time Kinematic (RTK) Service

    The SatRef system produces the Network RTK correctional data stream to users by means of the SatRef NTRIP server. Users can obtain the correctional data stream via the internet. The real-time positional accuracy of Network RTK is about 3-5cm. It can be applied in topographic mapping, monitoring of structural movement (e.g. building, bridge), machine guidance, etc.


Differential GNSS (DGNSS) Positioning Service

    The SatRef system produces the DGNSS correctional data stream to users by means of the SatRef NTRIP server. Users can obtain the DGNSS correctional data stream via the internet. The real-time positional accuracy of DGNSS is about 1-2m. It can be applied in navigation (land and sea), fleet management, location based services, mobile GIS systems, etc.


Application


Connection Settings

    Hostname: www.geodetic.gov.hk
    Port: 2101
    Login: Your Username and Password
    Access Point Name (APN): If you connect to our NTRIP server through Mobile Telecommunications Services, please check the APN setting with service provider.

Mountpoint Information

    Radio Technical Commission for Maritime Services (RTCM) Standard is used in this service.


    Mountpoint VRS_1023* VRS_1024* VRS FKP31 FKP FKP23 DGPS
    Type Network RTK DGNSS
    RTCM format v3.1 v3.1 v3.1 v3.1 v3.0 v2.3 v2.2
    Network Type VRS VRS VRS FKP FKP FKP N/A
    Satellite System GPS
    GLO
    GPS
    GLO
    GPS
    GLO
    GPS
    GLO
    GPS
    GLO
    GPS GPS
    GLO
    Remarks with Geoid Correction - - - - Use HKSC or HKPC as reference
    Message
    Type
    Message Name RTCM 3 Message Type Included
    1004 Extended L1&L2 GPS RTK Observables
    1006 Stationary RTK Reference Station ARP with Antenna Height
    1008 Antenna Descriptor & Serial Number
    1012 Extended L1&L2 GLONASS RTK Observables
    1019 GPS Ephemerides
    1020 GLONASS Ephemerides
      1021*1 Helmert Transformation Parameters    √ *2    √ *3
    1023 Residuals, Ellipsoidal Grid Representation
    1024 Residuals, Plane Grid Representation
    1025 Projection Parameters
    1029 Unicode Text String
    1030 GPS Network RTK Residual Message
    1031 GLONASS Network RTK Residual Message
    1032 Physical Reference Station Position Message
    1033 Receiver and Antenna Descriptors
    1034 GPS Network FKP Gradient
    1035 GLONASS Network FKP Gradient
    Message
    Type
    Message Name RTCM 2 Message Type Included
    1 Differential GPS Corrections
    3 Reference Station Coordinates
    14 GPS Time
    16 Special Message (ASCII text)
    20 RTK Carrier Phase Corrections
    21 RTK Pseudorange Corrections
    22 Extended Reference Station Parameters
    23 Antenna Description
    24 Coordinates of Antenna Reference Point (ARP)
    31 Differential GLONASS Corrections

    *1 In order to fulfill the requirement of RTCM Standard, the 7-P datum transformation parameters transmitted in Message Type 1021 are slightly different from the published 7P_ITRF96_HK80_V1.0 data sheet.
    (Rotation parameters: round to the nearest 0.00002"; Scale: round to the nearest 0.00001ppm)

    *2 The Height Indicator of Message Type 1021 of Mountpoint VRS_1023 was set to 2 (i.e. value between [Height above HKPD] and [WGS84 Ellipsoidal Height] would be transmitted) on 11 July, 2018.

    *3 The Height Indicator of Message Type 1021 of Mountpoint VRS_1024 was set to 1 (i.e. value between [Height above HKPD] and [HK80 Ellipsoidal Height] would be transmitted) on 11 July, 2018.

    Remark:

    1. For more details, please refer to NTRIP source table.

    2. Please check the technical specifications of your receivers for selection of the most appropriate type of service and compatible RTCM format. For GNSS receiver settings, please refer to this link or contact with vendor.


Enquiry

Tel : (852) 2231 3497
Fax : (852) 2116 0778
Email : geodetic@landsd.gov.hk