Patent ID: 8319682

Claim:
A method for examining an object using electromagnetic millimeter-wave signal illumination; the method comprising: (a) providing at least two electromagnetic millimeter-wave signal sources; (b) transmitting at least two electromagnetic millimeter-wave signals from said at least two electromagnetic millimeter-wave signal sources to illuminate said object; said at least two electromagnetic millimeter-wave signals having at least two different frequencies; (c) in no particular order: (1) determining whether a return reflected signal from said object is above a predetermined threshold signal level; [a] if said return reflected signal is above said predetermined threshold signal level, processing said return reflected signal to identify shape of said object; [b] if said return reflected signal is not above said predetermined threshold signal level; processing another return signal; and (2) determining whether a return intermodulation product or harmonic signal from said object is detected; [a] if said return intermodulation product or harmonic signal is detected, processing said return intermodulation product or harmonic signal to identify nature of said object; [b] if said return intermodulation product or harmonic signal is not detected; processing another return signal; (d) determining whether all return signals have been checked; (1) if all return signals have not been checked, processing another return signal; (2) if all return signals have been checked, proceeding to step (e); (e) determining whether the method has yielded satisfactory results; (1) if the method has not yielded satisfactory results, changing frequency of at least one of said at least two electromagnetic millimeter-wave signals and repeating steps (b) through (e); (2) if the method has yielded satisfactory results, terminating the method.