Receiving Properties of the Small Annular-Slot Antenna

An analytical formula for the effective height of an annularslot antenna is determined using the reciprocity theorem. This result generalizes the previously available single-frequency steady-state result and yields an equivalent circuit valid for computing the transient response of the small annular-slot antenna. the theory has application in calibrating near-zone field strength instrumentation and in determining the response of an unsheathed coaxial cable connector mounted flush with the skin of a missile to intense plane-wave electromagnetic field pulses.