github.com/bramburn/gnssgo/pkg/gnssgo

GNSSGO - Go GNSS RTK Library

GNSSGO is a Go implementation of RTKLIB, providing similar functionality for GNSS data processing and positioning. It can be imported into your Go applications to add RTK and other GNSS processing capabilities.

Main Features

• Processing RTK (Real-Time Kinematic) GNSS data
• Calculating precise positioning from GNSS receiver data
• Support for multiple satellite systems (GPS, GLONASS, Galileo, BeiDou, QZSS, IRNSS)
• Various positioning modes (single, DGPS/DGNSS, kinematic, static, PPP-Kinematic, PPP-Static)
• RINEX file handling and conversion
• Support for standard formats (RINEX, RTCM, BINEX, etc.)
• Serial, TCP/IP, NTRIP, and file handling

Key Types

• Rtk: RTK control/result type for RTK positioning Used to perform RTK positioning with observation data

• Sol: Solution type for positioning results Contains position, velocity, and other solution information

• PrcOpt: Processing options for positioning Configuration options for positioning algorithms

• Nav: Navigation data including ephemeris Contains satellite orbit and clock information

• ObsD: Observation data Contains GNSS observation data from receivers

• RtkSvr: RTK server for continuous positioning Provides continuous positioning with data streams

• Stream: Communication stream Handles various types of communication (serial, TCP, file, etc.)

• RTKStatus: RTK status information Contains information about the current RTK status

Key Functions

• Rtk.RtkPos: Performs RTK positioning Process observation data to calculate precise positions

• PntPos: Performs single point positioning Calculate position from a single receiver's observations

• Nav.SatPoss: Calculates satellite positions Compute satellite positions from navigation data

• RtkSvr.RtkSvrStart: Starts the RTK server Begin continuous positioning with data streams

• ConvRnx: Converts receiver raw data to RINEX format Convert raw receiver data to standard RINEX format

• ReadRnx: Reads RINEX files Parse RINEX observation and navigation files

• Stream.OpenStream: Opens a communication stream Establish communication with receivers or other data sources

Usage Examples

For comprehensive usage examples, see the examples directory in the repository. Examples include basic usage, RTK positioning, file handling, and serial communication.

RTCM Message Filtering

The library includes functionality for filtering RTCM messages:

• DefaultRTCMFilter: Provides a default filter that excludes unnecessary message types
• CriticalRTCMFilter: Provides a filter that only allows critical message types for RTK
• FilterRTCMMessages: Filters RTCM messages based on the provided filter

NMEA Parsing

The library includes functionality for parsing NMEA sentences:

• ParseNMEA: Parses an NMEA sentence
• ParseGGA: Parses a GGA sentence
• CalculateNMEAChecksum: Calculates the checksum for an NMEA sentence

RTK Status

The library includes functionality for tracking RTK status:

• RTKStatus: Contains information about the current RTK status
• UpdateFromCovariance: Updates the RTK status based on covariance values
• UpdateFromNMEA: Updates the RTK status from a NMEA GGA sentence

Thread Safety

Most functions are thread-safe and can be used in concurrent Go routines. The library uses Go's concurrency primitives for thread safety.

License

This library is licensed under the MIT License. See the LICENSE file for details.