Understanding of electromagnetic wave propagation is foundational for prediction of communications system performance (connection quality, detection distance, etc.), for frequency planning during exercise or operationally, and for requirements specification of new systems. As new technologies, frequency uses and scenarios become militarily relevant, the requirements of the models used to describe the propagation also change. This report describes the work done during 2023-2025 in the project Radiokanalmodeller för framtida militära system (Radio channel models for future military systems) with the purpose of developing and improving wave propagation models. The project started with a literature study. The modelling of forest vegetation, and the wave propagation through it, was studied. This resulted in a suggested method for forest height estimation based on laser point data. The same data might also be used to estimate the density and electrical properties of the vegetation, but further work is needed. Calculation of wave propagation in three dimensions was investigated, with the conclusion that the computational complexity increases rapidly. Speeding up calculations, both through parallelization with graphical processing units and through approximate 3D models, was explored with promising results; parallelization was shown to be able to provide speedups of several times, and a 2026 thesis project will continue to investigate approximate 3D-models. Furthermore, the work has included processing of measurement data intended for validation of the studied models.