The aim of this project is to develop a propagation analysis tool helping the system designer to evaluate the impact of the atmosphere on a telecommunication link involving
- GEO or non-GEO satellites (LEO, MEO and HEO), including constellations
- Fixed or mobile receivers
The various propagation effects implemented in the system are: tropospheric effects (statistics for sites or regions, time series for sites), ionospheric effects for sites or regions, environment effects and interferences. Predefined systems, using models and inputs from ITU-R Recommendations, are presented to the user, as seen on Figure 1. Three systems are implemented: fixed telecommunication, mobile telecommunication and GNSS.
Figure 1: Selection of the predefined systems or the expert mode
The propagation expert can select various models and input datasets for each effect.
The output of the calculation contains graphs if applicable (Figure 2), ASCII files and Matlab files embedded in HDF5 format.
Figure 2: CCDF of attenuation due to clouds for various sites at 12.5 GHz
The key issue addressed by this project is to offer to a large variety of users, including system designers as well as propagation experts, a user’s friendly software for the calculation of the degradation due to the atmosphere and the environment.
This software gathers widely used models for the evaluation of the degradation due to the atmosphere (troposphere and ionosphere) and the environment in a single software, with a uniformed interface.
RAPIDS II, version Pastel, allows registered users to log-in, via Internet, and to perform propagation calculations. The Spring Webflow framework orchestrates the sequence of steps to collect all information from the user (models and input datasets), for the complex calculations the software needs to perform. Once a job definition is complete, the job is submitted to a SunGrid scheduler who will asynchronously send the job to the MATLAB calculation engine and track its execution. When the job is submitted, the user can do other actions, including launching new jobs or logging out. He can be notified by e-mail of the conclusion of a job. The output is in the form of statistical curves or time series for tropospheric attenuation, scintillation and environment. Output files are in HDF5, MATLAB and CSV formats.
The project is a collaboration between UCL as prime, with ONERA Toulouse (F) as subcontractor, Uniway (B), AETHIS (B) and UNIK (N).
The project, initially planned for 24 months, has been further extended by a CCN to a duration of 40 months due to the complexity of the software and the large number of effects to implement. The project is composed by 7 work packages. After a review of the models (WP1000), the models chosen for the various effects are developed and adapted (WP2000). The software requirements are determined and a first MMI interface is proposed during WP3000. The next phase is the software design and implementation, with the web application coding and the calculation module coding (WP4000); the following phase being devoted to validation and testing (WP5000). The last phase is the installation of the server and the software at ESTEC and the pilot period.
The server and the software have been installed at ESTEC on November 15, 2013. During the Pilot Period (January 2014-June 2014), a test version of the software is available on a Uniway server. Interested users can send an email to the contact persons hereafter.