| 摘要 |
<p>A system for the digital conversion of a time division multiplex signal into a frequency division multiplex signal wherein the signals of the individual time multiplex channels are filtered by means of bandpass filters, their sampling rates are increased by the factor N to fA and the output signals of these bandpass filters are combined, by means of a summing member, into the frequency multiplex signal, and/or a system for the digital conversion of a frequency multiplex signal into a time division multiplex signal, wherein the digitalized frequency multiplex signal is divided by means of respective bandpass filters into the signals of the individual frequency multiplex channels and their sampling rate fA is reduced by the factor N. The individual bandpass filters (BP) are designed as recursive filters having the transfer function where U1(z) and U2(z) represent the filter input and filter output spectra respectively, z = ej2.pi.f/fA, and f is the signal frequency.</p> |
