5.7 KiB
This is a collection of all the metrics collected by gpsdMeasurement.py script.
Table of contents
gps_fix
This measurement is the current navigation solution from the latest TPV message.
Basically: where am I, what kind of fix do I have, and how confident is the receiver?
mode
Fix type.
Usually:
1 = no fix
2 = 2D fix
3 = 3D fix
lat
Latitude in decimal degrees.
lon
Longitude in decimal degrees.
alt
Altitude in meters.This is effectively the same as mean sea level altitude.
alt_msl
Altitude above mean sea level, in meters.
alt_hae
Altitude above the ellipsoid, in meters.
speed
Current ground speed, in meters per second.
climb
Vertical speed, in meters per second. Positive means climbing, negative means descending.
track
Course over ground in degrees.
magtrack
Magnetic course over ground in degrees.
magvar
Magnetic variation in degrees.
ept
Estimated timestamp error, in seconds. This is gpsd estimate of uncertainty for the reported time.
epx
Estimated longitude-related horizontal uncertainty, in meters.
epy
Estimated latitude-related horizontal uncertainty, in meters.
epv
Estimated vertical uncertainty, in meters.
eph
Estimated horizontal position uncertainty, in meters.
sep
Estimated spherical error or 3D position uncertainty, in meters.
ecefpAcc
Estimated ECEF position accuracy, in meters.
ecefvAcc
Estimated ECEF velocity accuracy, in meters per second.
leapseconds
Current leap-second offset between GPS time and UTC.
fix_valid
Boolean derived by the script.
true if mode >= 2.
fix_3d
Boolean derived by the script.
true if mode == 3.
gps_sky
This measurement comes from the latest SKY message.
It says: how good is the sky view, how many satellites are visible and used, and how good is the geometry?
nSat
Number of satellites visible or reported.
uSat
Number of satellites currently used in the navigation solution.
sat_used_ratio
Derived value: uSat / nSat.
Shows how many visible satellites are actually being used.
gdop
Geometric dilution of precision.
Overall combined geometry quality. Lower is better.
hdop
Horizontal dilution of precision. Lower is better.
pdop
Position dilution of precision. Lower is better.
tdop
Time dilution of precision. Lower is better.
vdop
Vertical dilution of precision. Lower is better.
xdop
Dilution of precision in the X direction. Lower is better.
ydop
Dilution of precision in the Y direction. Lower is better.
gps_visible
How many GPS satellites were listed.
gps_used
How many GPS satellites were actually used in the fix.
sbas_visible
How many SBAS satellites were listed.
sbas_used
How many SBAS satellites were used in the fix.
galileo_visible
How many Galileo satellites were listed.
galileo_used
How many Galileo satellites were used in the fix.
beidou_visible
How many BeiDou satellites were listed.
beidou_used
How many BeiDou satellites were used in the fix.
qzss_visible
How many QZSS satellites were listed.
qzss_used
How many QZSS satellites were used in the fix.
glonass_visible
How many GLONASS satellites were listed.
glonass_used
How many GLONASS satellites were used in the fix.
unknown_visible
How many satellites had an unknown gnssid.
unknown_used
How many unknown-constellation satellites were used.
avg_signal_visible
Average signal strength across all visible satellites, based on ss.
avg_signal_used
Average signal strength across satellites actually used in the fix.
max_signal
Maximum ss value seen among visible satellites.
gps_pps
This measurement comes from the latest PPS message.
What is says: is PPS present, and what is the current timing offset between the PPS event and the host clock timestamp?
offset_ns
Derived value in nanoseconds.
Calculated by the script as:
(clock_sec * 1e9 + clock_nsec) - (real_sec * 1e9 + real_nsec)
The difference between the kernel or host timestamp and the PPS event timestamp.
A negative value means the host timestamp is slightly earlier than the PPS reference. A positive value means it is slightly later.
precision_exp
Precision exponent reported by gpsd for the PPS source.
present
Boolean derived by the script.
Always true when a PPS message was received and exported.