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# SensorGps (UORB message)
GPS position in WGS84 coordinates. the field 'timestamp' is for the position & velocity (microseconds).
**TOPICS:** sensor_gps vehicle_gps_position
## Fields
| Name | Type | Unit [Frame] | Range/Enum | Description |
| ----------------------- | --------- | ------------------ | ---------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| timestamp | `uint64` | | | time since system start (microseconds) |
| timestamp_sample | `uint64` | | |
| device_id | `uint32` | | | unique device ID for the sensor that does not change between power cycles |
| latitude_deg | `float64` | | | Latitude in degrees, allows centimeter level RTK precision |
| longitude_deg | `float64` | | | Longitude in degrees, allows centimeter level RTK precision |
| altitude_msl_m | `float64` | | | Altitude above MSL, meters |
| altitude_ellipsoid_m | `float64` | | | Altitude above Ellipsoid, meters |
| s_variance_m_s | `float32` | | | GPS speed accuracy estimate, (metres/sec) |
| c_variance_rad | `float32` | | | GPS course accuracy estimate, (radians) |
| fix_type | `uint8` | | | Some applications will not use the value of this field unless it is at least two, so always correctly fill in the fix. |
| eph | `float32` | | | GPS horizontal position accuracy (metres) |
| epv | `float32` | | | GPS vertical position accuracy (metres) |
| hdop | `float32` | | | Horizontal dilution of precision |
| vdop | `float32` | | | Vertical dilution of precision |
| noise_per_ms | `int32` | | | GPS noise per millisecond |
| automatic_gain_control | `uint16` | | | Automatic gain control monitor |
| jamming_state | `uint8` | | | indicates whether jamming has been detected or suspected by the receivers. O: Unknown, 1: OK, 2: Mitigated, 3: Detected |
| jamming_indicator | `int32` | | | indicates jamming is occurring |
| spoofing_state | `uint8` | | | indicates whether spoofing has been detected or suspected by the receivers. O: Unknown, 1: OK, 2: Mitigated, 3: Detected |
| authentication_state | `uint8` | | | GPS signal authentication state |
| vel_m_s | `float32` | | | GPS ground speed, (metres/sec) |
| vel_n_m_s | `float32` | | | GPS North velocity, (metres/sec) |
| vel_e_m_s | `float32` | | | GPS East velocity, (metres/sec) |
| vel_d_m_s | `float32` | | | GPS Down velocity, (metres/sec) |
| cog_rad | `float32` | | | Course over ground (NOT heading, but direction of movement), -PI..PI, (radians) |
| vel_ned_valid | `bool` | | | True if NED velocity is valid |
| timestamp_time_relative | `int32` | | | timestamp + timestamp_time_relative = Time of the UTC timestamp since system start, (microseconds) |
| time_utc_usec | `uint64` | | | Timestamp (microseconds, UTC), this is the timestamp which comes from the gps module. It might be unavailable right after cold start, indicated by a value of 0 |
| satellites_used | `uint8` | | | Number of satellites used |
| system_error | `uint32` | | | General errors with the connected GPS receiver |
| heading | `float32` | | | heading angle of XYZ body frame rel to NED. Set to NaN if not available and updated (used for dual antenna GPS), (rad, [-PI, PI]) |
| heading_offset | `float32` | | | heading offset of dual antenna array in body frame. Set to NaN if not applicable. (rad, [-PI, PI]) |
| heading_accuracy | `float32` | | | heading accuracy (rad, [0, 2PI]) |
| rtcm_injection_rate | `float32` | | | RTCM message injection rate Hz |
| selected_rtcm_instance | `uint8` | | | uorb instance that is being used for RTCM corrections |
| rtcm_crc_failed | `bool` | | | RTCM message CRC failure detected |
| rtcm_msg_used | `uint8` | | | Indicates if the RTCM message was used successfully by the receiver |
| antenna_offset_x | `float32` | m [body frame FRD] | | X Position of GNSS antenna |
| antenna_offset_y | `float32` | m [body frame FRD] | | Y Position of GNSS antenna |
| antenna_offset_z | `float32` | m [body frame FRD] | | Z Position of GNSS antenna |
## Constants
| Name | Type | Value | Description |
| --------------------------------------------------------------------------------- | -------- | ----- | ------------------------------------------ |
| FIX_TYPE_NONE | `uint8` | 1 | Value 0 is also valid to represent no fix. |
| FIX_TYPE_2D | `uint8` | 2 |
| FIX_TYPE_3D | `uint8` | 3 |
| FIX_TYPE_RTCM_CODE_DIFFERENTIAL | `uint8` | 4 |
| FIX_TYPE_RTK_FLOAT | `uint8` | 5 |
| FIX_TYPE_RTK_FIXED | `uint8` | 6 |
| FIX_TYPE_EXTRAPOLATED | `uint8` | 8 |
| JAMMING_STATE_UNKNOWN | `uint8` | 0 | default |
| JAMMING_STATE_OK | `uint8` | 1 |
| JAMMING_STATE_MITIGATED | `uint8` | 2 |
| JAMMING_STATE_DETECTED | `uint8` | 3 |
| SPOOFING_STATE_UNKNOWN | `uint8` | 0 | default |
| SPOOFING_STATE_OK | `uint8` | 1 |
| SPOOFING_STATE_MITIGATED | `uint8` | 2 |
| SPOOFING_STATE_DETECTED | `uint8` | 3 |
| AUTHENTICATION_STATE_UNKNOWN | `uint8` | 0 | default |
| AUTHENTICATION_STATE_INITIALIZING | `uint8` | 1 |
| AUTHENTICATION_STATE_ERROR | `uint8` | 2 |
| AUTHENTICATION_STATE_OK | `uint8` | 3 |
| AUTHENTICATION_STATE_DISABLED | `uint8` | 4 |
| SYSTEM_ERROR_OK | `uint32` | 0 | default |
| SYSTEM_ERROR_INCOMING_CORRECTIONS | `uint32` | 1 |
| SYSTEM_ERROR_CONFIGURATION | `uint32` | 2 |
| SYSTEM_ERROR_SOFTWARE | `uint32` | 4 |
| SYSTEM_ERROR_ANTENNA | `uint32` | 8 |
| SYSTEM_ERROR_EVENT_CONGESTION | `uint32` | 16 |
| SYSTEM_ERROR_CPU_OVERLOAD | `uint32` | 32 |
| SYSTEM_ERROR_OUTPUT_CONGESTION | `uint32` | 64 |
| RTCM_MSG_USED_UNKNOWN | `uint8` | 0 |
| RTCM_MSG_USED_NOT_USED | `uint8` | 1 |
| RTCM_MSG_USED_USED | `uint8` | 2 |
## Source Message
[Source file (GitHub)](https://github.com/PX4/PX4-Autopilot/blob/main/msg/SensorGps.msg)
::: details Click here to see original file
```c
# GPS position in WGS84 coordinates.
# the field 'timestamp' is for the position & velocity (microseconds)
uint64 timestamp # time since system start (microseconds)
uint64 timestamp_sample
uint32 device_id # unique device ID for the sensor that does not change between power cycles
float64 latitude_deg # Latitude in degrees, allows centimeter level RTK precision
float64 longitude_deg # Longitude in degrees, allows centimeter level RTK precision
float64 altitude_msl_m # Altitude above MSL, meters
float64 altitude_ellipsoid_m # Altitude above Ellipsoid, meters
float32 s_variance_m_s # GPS speed accuracy estimate, (metres/sec)
float32 c_variance_rad # GPS course accuracy estimate, (radians)
uint8 FIX_TYPE_NONE = 1 # Value 0 is also valid to represent no fix.
uint8 FIX_TYPE_2D = 2
uint8 FIX_TYPE_3D = 3
uint8 FIX_TYPE_RTCM_CODE_DIFFERENTIAL = 4
uint8 FIX_TYPE_RTK_FLOAT = 5
uint8 FIX_TYPE_RTK_FIXED = 6
uint8 FIX_TYPE_EXTRAPOLATED = 8
uint8 fix_type # Some applications will not use the value of this field unless it is at least two, so always correctly fill in the fix.
float32 eph # GPS horizontal position accuracy (metres)
float32 epv # GPS vertical position accuracy (metres)
float32 hdop # Horizontal dilution of precision
float32 vdop # Vertical dilution of precision
int32 noise_per_ms # GPS noise per millisecond
uint16 automatic_gain_control # Automatic gain control monitor
uint8 JAMMING_STATE_UNKNOWN = 0 #default
uint8 JAMMING_STATE_OK = 1
uint8 JAMMING_STATE_MITIGATED = 2
uint8 JAMMING_STATE_DETECTED = 3
uint8 jamming_state # indicates whether jamming has been detected or suspected by the receivers. O: Unknown, 1: OK, 2: Mitigated, 3: Detected
int32 jamming_indicator # indicates jamming is occurring
uint8 SPOOFING_STATE_UNKNOWN = 0 #default
uint8 SPOOFING_STATE_OK = 1
uint8 SPOOFING_STATE_MITIGATED = 2
uint8 SPOOFING_STATE_DETECTED = 3
uint8 spoofing_state # indicates whether spoofing has been detected or suspected by the receivers. O: Unknown, 1: OK, 2: Mitigated, 3: Detected
# Combined authentication state (e.g. Galileo OSNMA)
uint8 AUTHENTICATION_STATE_UNKNOWN = 0 #default
uint8 AUTHENTICATION_STATE_INITIALIZING = 1
uint8 AUTHENTICATION_STATE_ERROR = 2
uint8 AUTHENTICATION_STATE_OK = 3
uint8 AUTHENTICATION_STATE_DISABLED = 4
uint8 authentication_state # GPS signal authentication state
float32 vel_m_s # GPS ground speed, (metres/sec)
float32 vel_n_m_s # GPS North velocity, (metres/sec)
float32 vel_e_m_s # GPS East velocity, (metres/sec)
float32 vel_d_m_s # GPS Down velocity, (metres/sec)
float32 cog_rad # Course over ground (NOT heading, but direction of movement), -PI..PI, (radians)
bool vel_ned_valid # True if NED velocity is valid
int32 timestamp_time_relative # timestamp + timestamp_time_relative = Time of the UTC timestamp since system start, (microseconds)
uint64 time_utc_usec # Timestamp (microseconds, UTC), this is the timestamp which comes from the gps module. It might be unavailable right after cold start, indicated by a value of 0
uint8 satellites_used # Number of satellites used
uint32 SYSTEM_ERROR_OK = 0 #default
uint32 SYSTEM_ERROR_INCOMING_CORRECTIONS = 1
uint32 SYSTEM_ERROR_CONFIGURATION = 2
uint32 SYSTEM_ERROR_SOFTWARE = 4
uint32 SYSTEM_ERROR_ANTENNA = 8
uint32 SYSTEM_ERROR_EVENT_CONGESTION = 16
uint32 SYSTEM_ERROR_CPU_OVERLOAD = 32
uint32 SYSTEM_ERROR_OUTPUT_CONGESTION = 64
uint32 system_error # General errors with the connected GPS receiver
float32 heading # heading angle of XYZ body frame rel to NED. Set to NaN if not available and updated (used for dual antenna GPS), (rad, [-PI, PI])
float32 heading_offset # heading offset of dual antenna array in body frame. Set to NaN if not applicable. (rad, [-PI, PI])
float32 heading_accuracy # heading accuracy (rad, [0, 2PI])
float32 rtcm_injection_rate # RTCM message injection rate Hz
uint8 selected_rtcm_instance # uorb instance that is being used for RTCM corrections
bool rtcm_crc_failed # RTCM message CRC failure detected
uint8 RTCM_MSG_USED_UNKNOWN = 0
uint8 RTCM_MSG_USED_NOT_USED = 1
uint8 RTCM_MSG_USED_USED = 2
uint8 rtcm_msg_used # Indicates if the RTCM message was used successfully by the receiver
float32 antenna_offset_x # [m] [@frame body frame FRD] X Position of GNSS antenna
float32 antenna_offset_y # [m] [@frame body frame FRD] Y Position of GNSS antenna
float32 antenna_offset_z # [m] [@frame body frame FRD] Z Position of GNSS antenna
# TOPICS sensor_gps vehicle_gps_position
```
:::