Frequency multiplier

Claim 1

IN A APPARATUS FOR PRODUCING MICROWAVE ENERGY AT A PRESELECTED FREQUENCY, THE COMBINATION OF A SOURCE OF ELECTRICAL EXCITATION AT A FREQUENCY WHICH IS AN INTEGRAL SUB-HARMONIC OF THE SELECTED FREQUENCY, A SUBSTANTIALLY LOSSLESS AND PREDOMINANTLY REACTIVE ELEMENT HAVING A NON LINEAR REACTANCE CHARACTERISTIC TO EXCITATION VOLTGE, A RECTANGULAR WAVEGUID HOUSING REACTANCE ELEMENT AND HAVING A DEPTH CROSS SECTIONAL DIMENSION PARALLEL TO THE DIRECTION OF THE ELECTRICAL FIELD IN THE TE. MODE AND A WIDTH CROSS SECTIONAL DIMENSION PERPENDICULAR TO THE DIRETION OF SAID ELECTRIC FIELD, THE WIDTH DIMENSION BEING SUCH THAT THE CUTOFF FREQUENCY OF THE WAVEGUIDE HOUSING THE REACTANCE ELEMENT LIES ABOVE THE HARMONIC OF THE INPUT FREQUENCY WHICH IS NEAREST AND BELOW THE SELECTED FREQUENCY AND THE DEPTH DIMENSION IS PROPORTIONED TO SUBSTANTIALLY MATCH THE IMPEDANCE OF THE REACTANCE ELEMENT, A CAVITGY SEPARATE AND REMOTE FROM SAID REACTANCE ELEMENT AND TUNED TO THE SELECTED MICROWAVE FREQUNECY AND HAVING AN INPUT AND OUTPUT STRUCTURES, MEANS COUPLING THE REACTANCE ELEMENT TO THE CAVITY INPUT STRUCTURE FOR APPLYING THE SELECTED FREQUENCY EMANATIONS OF THE REACTANCE ELEMENT TO THE CAVITY AND REFLECTING A VOLTAGE MINIMUM AT THE ELEMENT FOR UNDESIRED HARMONICS, AND MEANS COUPLING THE ELECTRICAL EXCITATION SOURCE AND REACTANCE ELEMENT FOR APPLYING THE ELECTRICAL EXCITATION FROM THE SOURCE TO THE REACTANCE ELEMENT AND REFLECTING A VOLTAGE MINIMUM AT THE ELEMENT OF UNDESIRED HARMONICS.