Sinusoidal signal frequency and amplitude determn. method

摘要

A Fourier transform is made of the signal from a time (t) to (t+T) by filters (1) which encompass the unknown frequency (V0). A comparator (2) is used to determine the frequency (V1) for which the output signal is a max. and the real and imaginary values of the amplitude are stored in a memory (3). At a later time (t+T1) a further Fourier transform is made over the same time interval (T) as the first. The real and imaginary values obtd. at the output of the filter for the frequency (V1) giving max. output signal are again stored in the memory (3). The signal frequency and amplitude are calculated by a computer (4) from the stored data.