Wave analysis system utilizing time reversal

Claim 1

APPARATUS FOR ANALYZING A COMPLEX PERIODIC WAVE TO DEVELOP INDIVIDUAL INDICATIONS OF THE COEFFICIENTS OF THE COSIN TERMS AND OF THE SINE TERMS OF ITS FOURIER SERIES EXPANSION WHICH COMPRISES MEANS FOR MAKING A SPACE-VARIANT RECORD OF SAID WAVE, MEANS FOR SCANNING SAID RECORD IN ONE DIRECTION TO DEVELOP A FORWARD TIME WAVE V(T), MEANS FOR SCANNING SAID RECORD IN THE OPPOSITE DIRECTION TO DEVELOP A REVERSE TIME WAVE V(-T), MEANS FOR ADDITIVELY AND SUBSTANTIALLY COMBINING SAID WAVES TO FORM A SUM WAVE V(T)+V(-T) AND A DIFFERENCE WAVE V(T), AN AUXILIARY, SINGLE-PHASE SOURCE OF VARIABLE FREQUENCY OSCILLATIONS, MEANS FOR INDIVIDUALLY MODULATING SAID SUM WAVE AND SAID DIFFERENCE WAVE BY THE OSCILLATIONS OF SAID AUXILIARY SOURCE TO DEVELOP A FIRST AND A SECOND PRODUCT WAVE, FILTER MEANS FOR INDIVIDUALLY SELECTING, FROM AMONG THE COMPONENTS OF SAID FIRST AND SECOND PRODUCT WAVES, ONLY THOSE THAT LIE WITHIN A SPECIFIED FREQUENCY BAND, AND MEANS FOR INDICATING THE MAGNITUDES OF SAID SELECTED COMPONENTS INDIVIDUALLY, WHEREBY, FOR EACH DISTINCT FREQUENCY OF SAID AUXILIARY OSCILLATIONS, THE AMPLITUDES OF SAID SELECTED COMPONENTS ARE PROPORTIONAL, RESPECTIVELY, TO THE DESIRED COSIN TERM COEFFICIENT AND THE DESIRED SINE TERM COEFFECIENT OF SAID COMPLES WAVE FOR A CORRESPONDING FREQUENCY.