Image processing framework to integrate EM software packages.
...Scipion allows to execute workflows combining different software tools, while taking care of formats and conversions. Additionally, all steps are tracked and can be reproduced later on.
Xmipp is a well-known package in the EM image processing. It is integrated into Scipion and contains the algorithms in the core libraries and command line programs.
NecJGui is an antennas design tool, interface for Numerical Electromagnetic Code. It allows easily making NEC input files, and viewing them in 3D. It also contains a version of the simulator, so it's complete IDE for full-wave EM simulation.