Statistical Field Model for Performance of Localized RF Absorption Blankets in a Payload Fairing

In the space community, there is increasing interest in adaption and augmentation of launch fairing thermal-acoustic blankets, to also control electromagnetic environment threats. This paper reports on the development of simulation methods to both optimize blanket materials for RF absorption and to provide quantitative guidance on their minimal spatial deployment inside the fairing. A stochastic power-balance model with multiple connected sub-cavities is used to map the reverberant electric field in the fairing when RF absorbing blankets are applied only locally – ie only partial coverage of the fairing wall. The sub-cavity Q factors resulting from different RF absorption blanket materials is calculated from published reflection loss data and a field incidence correction factor. Comparison with model-scale test data, verifies that the model correctly predicts the electric field attenuation of different absorber materials. The model also correctly predicts the spatial distribution of the field and the improvement in shielding effectiveness.