Modelling of EM propagation in simplified jet turbine structure using helical rays

To explain the variations in field strength measurements seen when measuring radio-frequency (RF) propagation in jet turbines, a model based on helical propagating waves is presented. The model uses a simplified model of the jet turbine based on a cylindrical structure and is compared with both electromagnetic (EM) simulations and measured values. Measurements and simulated values show good correspondence and show that a sum of helical propagating waves could be a useful tool to model the expected field variations.