| 摘要 |
A Doppler shift compensation apparatus for compensating Doppler frequency shifts in an incoming signal to reproduce a highly accurate signal. The Doppler shift compensation apparatus has high frequency dissolution ability and can detect a frequency, an amplitude and a phase of the incoming signal accurately. The Doppler shift compensation apparatus includes an analog to digital converter which transforms an analog input signal to digital data, a memory which stores the digital data from the analog to digital converter, a window function weighting part for multiplying a specified window function to input data from the memory, a fast Fourier transformer (FFT) for transforming the input data to frequency spectrum data, an interpolation judgment part which distinguishes line spectrum from dispersed spectrum in the frequency spectrum data from the fast Fourier transformer, a spectrum interpolator which measures the true frequency, amplitude and phase of the line spectrum based on the judgement of the interpolation judgement part, an accumulator for accumulating the frequency domain data interpolated by the spectrum interpolator, a summation part for vector-summing the frequency domain data accumulated by the accumulator to a Fourier transform output of the fast Fourier transformer, a regression computation part for performing a predetermined regression computation for the frequency data from the summation part based on the output data from the interpolation judgment part, and a subtractor for subtracting the output data of said regression computation part from the frequency data from the summation part.
|
