TH1518B - Arrangement of filter circuits for use in signaling systems - Google Patents

Abstract

It is a filter circuit arrangement for use in signal processing systems of the type operating with signals at first and second frequencies. The arrangement was made using three second-order filter circuits (B1, B2, and B3), each of which has coefficients, a, A and b filter circuits, (B1) and (B2) filter circuits, and a filter (B1). ) And (B3) are connected. Filter (B2) filter output signal (F1), which is an indication of a filter circuit with a finite-gain resonator characteristic signal with a center frequency at the first frequency. Filter circuit (B3) Filter output signal (F2, F3) The F2 signal is indication of a filter circuit with a finite-gain resonator signal that has a center frequency at two And zero at the first frequency, and the signal (F3) indicates a filter circuit centered at the first and second frequencies.

Claims (4)

1. The arrangement of filter circuits for use in signaling systems of the type operating on signals at the first and second frequencies f1 and f2 are achieved by using more than one ordinal filter circuit. Each circuit has a filter coefficient a, A and b, the first and second output terminals, and the input terminals look like One filter circuit receives an input at its input terminal. And at the output terminal on one of it creates a resonator characteristic signal. Gain is limited to frequency f1 and passes to the input terminal of the second filter circuit. And the first filter at its second output terminal has a zero signal at frequency f1, which is passed to the input terminal of the third filter. The second output terminal of the second filter produces the composite signal F1, and the first output terminal of the third filter circuit produces the composite signal F2, and the second output terminal of the third filter produces the composite signal F3, the F1, F2, and F3 signals are generated. With the input signal And the values of the filter coefficients a, A and b. Here, the F1 signal is the indication of the filter circuit with a finite gain resonator signal. With an intermediate frequency at the first frequency f1 and zero at the second frequency f2, the F2 signal is indication of a filter circuit with a finite-gain resonator signal with a center frequency at the second frequency f2 and zero at The first frequency f1 and the signal F3 are indications of the centered filter circuit at the first and second frequencies f1 and f2. 2. Arrangement of the filter circuit requested to claim claim 1, here the frequency of the first signal is 2,400 Hz and the frequency of the second signal is 2,600 Hz. 3. The filter arrangement requested in claim 1 or 2. Here the coefficient values for the first filter circuit are a = 0.5624, A = 0.6180 and b = 0.8281. 4. Filter arrangement requested in claim 3 Here, the values of the filter circuit for the second and third filter circuits are a = 0.8172, A = 0.9080 and b = 0.8100.