Electrical signal analyzing systems

Claim 1

IN A SIGNAL ANALYZING SYSTEM, THE COMBINATION OF: FIRST AND SECOND TERMINAL MEANS COUPLED TO RECEIVE FIRST AND SECOND ELECTRICAL SIGNALS HAVING COMPLEX MULTIFREQUENCY COMPONENTS CONTAINING MUTUALLY COHERENT SIGNAL COMPONENTS; FIRST MEANS COUPLED TO SAID FIRST AND SECOND TERMINAL MEANS FOR PROVIDING AN ELECTRICAL OUTPUT SIGNAL SUBSTANTIALLY CORRESPONDING TO THE PRODUCT OF SAID FIRST AND SECOND ELECTRICAL SIGNALS; CONTROLLABLE SIGNAL DELAY MEANS INTERPOSED BETWEEN AT LEAST ONE OF SAID TERMINAL MEANS AND SAID FIRST MEANS FOR INTRODUCING CONTROLLABLE AND KNOWN VALUES OF RELATIVE DELAY BETWEEN SIGNALS REACHING SAID FIRST MEANS; SECOND MEANS COUPLED TO SAID FIRST MEANS AND SAID SIGNAL DELAY MEANS FOR CONTROLLING THE VALUE OF RELATIVE DELAY INTRODUCED BY SAID SIGNAL DELAY MEANS IN RESPONSE TO SAID ELECTRICAL OUTPUT SIGNAL; AND ADJUSTABLE BANDPASS MEANS INTERPOSED BETWEEN AT LEAST ONE OF SAID TERMINAL MEANS AND SAID FIRST MEANS FOR SELECTIVELY CONTROLLING TO A SUBSTANTIAL EXTENT THE BANDWIDTH OF THE MUTUALLY COHERENT SIGNAL COMPOENTS OF THE FIRST AND SECOND ELECTRICAL SIGNALS REACHING SAID FIRST MEANS.