mirror of https://github.com/gnss-sdr/gnss-sdr synced 2025-11-07 18:54:06 +00:00

Files

Carles Fernandez 1d31c8427d skyplot improvements

Add new --format optional argument. Allowed options: pdf, eps, png, svg. Default: pdf
Add new --version / -v optional arguments, show program version and exit
Improve --help / -h message
Improve error handling
Generate PDF files with embedded fonts, ready for journal submission
Improve argument handling
Improve documentation
Add explicit z-order control for cleaner display of labels in multiconstellation files

2025-08-22 12:42:36 +02:00

.gitignore

Add a python script that generates a skyplot from a RINEX navigation file

2025-04-30 10:36:46 +02:00

README.md

skyplot improvements

2025-08-22 12:42:36 +02:00

skyplot.py

skyplot improvements

2025-08-22 12:42:36 +02:00

README.md

GNSS Skyplot utility

A Python script that generates polar skyplots from RINEX navigation files, showing satellite visibility over time.

Features

Processes RINEX navigation files.
Calculates satellite positions using broadcast ephemeris.
Plots satellite tracks in azimuth-elevation coordinates.
Customizable observer location.
Color-codes satellites by constellation (GPS, Galileo, GLONASS, BeiDou).
Elevation mask set to 5°, configurable via the --elev-mask option.
Outputs high-quality image in PDF format. EPS, PNG, and SVG formats are also available via the --format option.
Non-interactive mode for CI jobs with the --no-show option.
Constellations to plot can be configured via the --system option.
Optionally uses an OBS file to limit plot to the receiver observation time (--use-obs).
- When enabled, the tool looks for a matching file by replacing the last character of the NAV filename with O/o and uses it if found.

Requirements

Python 3.6+
Required packages:
- numpy
- matplotlib

Usage

Basic Command

./skyplot.py <RINEX_FILE> [LATITUDE] [LONGITUDE] [ALTITUDE]
             [--elev-mask ELEV_MASK]
             [--format {pdf,eps,png,svg}]
             [--no-show]
             [--system SYSTEM [SYSTEM ...]]
             [--use-obs]

Arguments

Argument	Type	Units	Description	Default
`RINEX_NAV_FILE`	Required	-	RINEX nav file path	-
`LATITUDE`	Optional	degrees (°)	North/South position	41.275°N
`LONGITUDE`	Optional	degrees (°)	East/West position	1.9876°E
`ALTITUDE`	Optional	meters (m)	Height above sea level	80.0 m
`--elev-mask`	Optional	degrees (°)	Elevation mask	5°
`--format`	Optional	-	Output {pdf,eps,png,svg}	pdf
`--no-show`	Optional	-	Do not show plot	-
`--system`	Optional	-	Systems to plot	All
`--use-obs`	Optional	-	Use RINEX obs data	-

Examples

Skyplot from default location (Castelldefels, Spain):
```
./skyplot.py brdc0010.22n
```
Skyplot from custom location (New York City, USA):
```
./skyplot.py brdc0010.22n 40.7128 -74.0060 10.0
```
Skyplot from custom location (Santiago, Chile) using receiver observation time:
```
./skyplot.py brdc0010.22n -33.4592 -70.6453 520.0 --use-obs
```

Non-interactive mode (for CI jobs):

./skyplot.py brdc0010.22n -33.4592 -70.6453 520.0 --no-show

Only plot GPS and Galileo satellites:

./skyplot.py brdc0010.22n -33.4592 -70.6453 520.0 --system GPS Galileo

./skyplot.py brdc0010.22n -33.4592 -70.6453 520.0 --system G E

Get a PNG file:

./skyplot.py brdc0010.22n -33.4592 -70.6453 520.0 --format png

Output

The script generates a PDF file named skyplot_<RINEX_FILE>.pdf (with dots in <RINEX_FILE> replaced by _) with:

Satellite trajectories over all epochs in the file.
- NAV file - ephemeris time range (default).
- Receiver observation if --use-obs is specified and OBS file is found.
Color-coded by constellation.
Observer location in title.
Time range in footer.
Embedded fonts that display consistently across all systems and generate publication-ready figures.
EPS, PNG, and SVG output formats available via --format eps, --format png, and --format svg.