Linear Periodic Time Varying Filtering of Cyclostationary Signals in Transmission Lines

Theoretical and experimental evaluation of the cyclostationary random data transferring process corrupted by the individually and jointly cyclostationary crosstalk interference added by stationary noise with possible deterministic component of the synchronizing clock signal is presented. The interference and the message signals were measured by the real time digital oscilloscope and autocorrelation functions were evaluated by synchronous cyclic averaging procedure. The analyzed periodic two-dimensional impulse response of the time-varying filter allows to obtain the output random process with the same cyclic frequency at the output of the filter by separation of orthogonal stationary waveforms constituting the input cyclostationary random process (CSRP). The filtering of the observed measured random process was implemented by cyclic Wiener filter, estimating the message from the measured random signal. The evaluation of two-dimensional autocorrelation function and eye diagrams at the output of the cyclic filter showed significant reduction of the independent interference components in the estimated message signal.