Analysis and design of enclosures for electromagnetic suscepibility measurements over a wide frequency range (20MHz-30GHz)

Absorber lined chambers (ALC's) or anechoic type enclosures operated under degraded conditions are introduced. Results of measurements inside scaled model ALC's are reported to demonstrate the feasibility of their use as environment simulators for electromagnetic susceptibility (E.M.S.) measurements over an extremely wide frequency range. The hardware and software of the automated microprocessor based facility developed for the measurement of amplitude and phase of e.m. fields in a volume of space, are described.A geometrical optic (GO) technique and an 'idealized' material model to predict ALC fields is developed. Computed results are presented for a range of cases including some whose measurement would not be practicable. Using measured and computed data, criteria and guidelines for economic ALC design are established.An experimental investigation of near-region scattering by various absorbers was carried out to seek the possibility of improving the material model with the objective of improving field prediction using the geometrical theory of diffraction (GTD)