Determining an Aircraft's Attenuation Characteristics of HIRF Testing

This paper elaborates on current testing techniques used to determine an aircraft's attenuation characteristics in the presence of High Intensity Radiated Fields (HIRF). This is not a theoretical discussion for the Electromagnetic expert, but rather a practitioner's overview for the avionics/electrical engineer who must oversee HIRF testing. Three testing techniques used to determine the attenuation of an aircraft will be discussed: (1) the Low Level Direct Drive (LLDD) test used for the 10 kHz to the first aircraft resonance frequency; (2) the Low Level Swept Current (LLSC) test used for the 1 to 400 MHz frequency band; and (3) the Low Level Swept Fields (LLSF) test used for the 100 MHz to 18 GHz frequency band.