The use of transmission line impedance measurements to determine electromagnetic comparability of FQIS wiring installations
Impedance measurements of a fuel quantity indication system (FQIS) were used to compare the electrical properties of a simulated FQIS installation to those of an actual installation. The fuel tank wiring and fuel probes from a Boeing 747 were removed from a retired airplane and installed in the reverberation chamber. The NASA installation was intended to electrically simulate the aircraft installation. A series of impedance measurements were taken on both installations in order to compare the input impedance values for each installation. A unique combination of statistics and the Smith Chart were used to compare the installations. This paper describes the methodology used in the data acquisition process, and the statistics of the installations are compared in the complex domain.