SatLink

SatLink is a python based application that runs speciffic satellite downlink calcullations. It has a GUI and his main functions are:

• Atmospheric attenuation calcullation (via itur)
• Single and multi-point downlink avaiability calcullation (input and output csv file)
• Antenna size estimation for a desired availability (single point graphic plot and multi point csv output)
• Save and load parameters for satellites, ground stations and reception characteristics
• Totally free !!!

This project is a attempt to simplify satellite's link budget calcullations and to create a tool for teaching purposes. Please check the documentation for more detailed information.

GUI Interface

For those that dont like code writing

• Simple Qt Gui made for simple usage
• Drop lists can be edited via model folder

To run the calcullations via GUI interface, run the python file main_window.py. The main window will appear. Now, just choose the functions in the action menu

Detailed information about the usage of the GUI can be found in the documentation.

A Satlink web app implementation can be used by building a dockerfile using this and runing satlink_web.py (needs to install streamlit package to work)

Using SatLink via python commands

SatLink consists of three main classes

• Satellite class
• Ground Station class
• Reception class

You need to define those three objects and set their relationship

from GrStat import GroundStation, Reception
from sat import Satellite

# creating the objects
station = GroundStation(site_lat, site_long)
sat = Satellite(sat_long, freq, eirp_max, hsat, b_transponder, b_util, _, _, mod, rolloff, fec)
receptor = Reception(ant_size, ant_eff, coupling_loss, polarization_loss, lnb_gain, lnb_noise_temp, cable_loss, desfoc_max)

# relating the objets to the satellite
sat.set_grstation(station)
sat.set_reception(receptor) 

# example - calcullating the link availability
availability = sat.get_availability()
print(availability)  # 0 - 100 percentage

# example - calcullating the power flux density in the reception point and the antenna noise in rain conditions
pw_flx = sat.get_power_flux_density()
print(pw_flx)  # watts/m²
ant_noise = sat.reception.get_antenna_noise_temp()
print(ant_noise)  # Kelvin
ant_noise_rain = sat.get_antenna_noise_rain()
print(ant_noise_rain)  # Kelvin

The other functions are detailed in the documentation.

Libraries

SatLink uses a bunch of different open source python libraries

• itur - A python implementation of the ITU-R P. Recommendations to compute atmospheric attenuation in slant and horizontal paths
• pyqt - PyQt is a set of Python bindings for The Qt Company's Qt application framework
• tqdm - Instantly make your loops show a smart progress meter
• pathos - It provides a consistent high-level interface for configuring and launching parallel computations across heterogeneous resources.
• pandas - Fast, powerful, flexible and easy to use open source data analysis and manipulation tool
• astropy - Common core package for Astronomy in Python and foster an ecosystem of interoperable astronomy packages
• numpy - The fundamental package for scientific computing with Python

Installation

SatLink has only been tested in python 3. Just copy all the folders and files to any directory and make sure all packages and dependencies are installed. For Linux users, be sure to install the required packages with the following one-liner (or the equivalent command in your current distribution):

sudo apt install build-essentials gcc g++ python3-pyqt5

For installing the Python packages, just run first_setup.py located in the main SatLink folder for a fresh package installation. Alternatively you can run the following command:

pip install -r requirements.txt

or

pip install numpy==1.26.4
pip install itur==0.4.0
pip install tqdm==4.66.5
pip install pandas==2.2.3
pip install pathos==0.3.3
pip install astropy==6.1.4
pip install pyqt5==5.15.2
pip install matplotlib==3.9.2
pip install chardet==5.2.0

Run main_window.py to start the applicaiton via interface.

For Linux users getting a QStandardPaths: wrong permissions on runtime directory /run/user/1000/ warning, enter the sudo chmod 0700 /run/user/1000/ command in your terminal.

For Linux users using a Conda environment that might be getting a libGL error: MESA-LOADER: failed to open swrast error, try installing gcc with the conda install gcc command.

Contributions

Since this is still a early version of the code, we expect there some problem can be found, We are tottaly open for contributions and bug/problems reports. Please tell us!

Future Developments

Some updates are planned for the future of the SatLink

• Worst month availabilty calcullation
• Web application
• Map function
• More robust XPD calculations

Authorship

All the code development was made by Christian Rodrigues.

Contact: christianfragoas@gmail.com

Credits

Globo - For supporting the very first release version of the application

Caio Alexandre - Logo designer