Antenna factor of compact antenna range for EMC measurements above 1GHz

A formula is proposed For measuring the antenna factor of an offset-fed par abolic reflector operated as a compact antenna range (CAR) by considering t he plane-wave approximation and field-distribution in the collimated region . The antenna factor is determined from the half power beamwidth (HPBW) of the feed, the physical geometry of the reflector and a field-distribution c orrection factor. The proposed formula is in good agreement with the measur ed results using a standard double-ridged horn antenna as the feed. The for mula can be used to design CARs for EMC applications.