The CNI open source satellite simulator based on OMNeT++

Satellite services (e.g. Internet-over-Satellite or GPS) are getting more and more important in our lives, whereby the operational area is still growing. To guarantee those services, reliable simulation tools are necessary to scale and validate actual and future satellite systems. Therefore, this paper gives an overview about development, functionalities and benefit of a satellite simulation framework which is already available for download, called the Open Source Satellite Simulator (OS). The use of OMNeT++ in combination with the INET framework allows the release under public license as well as a platform independent implementation. To provide an accurate and comfortable tool, OS features a Graphical User Interface, live weather data integration, high resolution altitude data, accurate satellite movements, different visualization options, channel modeling and much more. In order to ensure the correctness of simulation results, numerous experimental and simulation tests were conducted. A comparison between satellite position and movement predictions from OS and the corresponding values provided by a DLR (German Aerospace Center) hosted website proves the accuracy of the satellite movement simulation. The experimental validation was done by comparing simulated channel characteristics with actual measurements. The result is not only a benchmark of the accuracy of the simulation, it also proves the capability of OS to analyze existing or future satellite systems. Additionally, a simulation for VoIP transmission over a satellite link was implemented to show how OS can be applied to specific use cases.