| 摘要 |
<p>Digital filter bank for frequency separation of a frequency-multiplexed signal scanned at the detection frequency fA, in which the sums of the products of the detected values of the input signal with the finite pulse reply of the filter bank are subjected to a discrete Fourier transform (DFT) to form L complex output signals. By reducing the scanning rate by a factor of M«L only each M-th value of the sums produced is processed by the DFT. The invention is characterized by the fact that the frequency-multiplexed signal is a complex quantity on the input side, that a chain of N-1 delay elements is used, of which the delay time is 1/fA in order to delay the real part and the imaginary part of this quantity, that the detection of the individual values of the signal of the partial sequences is effected at a rate reduced by a factor M«L, that these signal values for the real and imaginary part are each multiplied by the coefficients of the pulse reply and the latter by complex coefficients and that each time the i-th complex signals are added to the L product sums.</p> |
