Microwave dimensional measuring apparatus and method

Claim 1

A METHOD OF MEASURING A SELECTED CHARACTERISTIC OF A BODY OF MATERIAL, COMPRISING THE STEPS OF EXCITING A RESONANT CAVITY WITH A HIGH FREQUENCY SIGNAL, MODULATING SAID HIGH FREQUENCY SIGNAL SO THAT A RANGE OF FREQUENCIES IS FED TO THE RESONATOR INCLUDING THE RESONANT FREQUENCY THEREOF PRIOR TO THE INTRODUCTION OF THE BODY THERETO, MONITORING THE SIGNAL REFLECTED FROM SAID RESONATOR, DERIVING AN ELECTRICAL SIGNAL INDICATIVE IF THE DIFFERENCE BETWEEN THE RESONANT FREQUENCY OF THE CAVITY PRIOR TO THE INTRODUCTION OF THE BODY AND THE RESONANT FREQUENCY OF THE CAVITY WITH THE BODY THEREIN, VARYING THE FREQUENCY OF THE HIGH FREQUENCY SOURCE IN RESPONSE TO SAID ELECTRICAL SIGNAL FOR RETURNING THE RESONATOR TO A RESONANT CONDITION WITH THE BODY THEREIN, SAID MEASURING SAID ELECTRICAL SIGNAL WHEREBY THE SELECTED CHARACTERISTIC OF THE BODY CAN BE DETERMINED.