Real-data digital-real-weight canceler

摘要

A canceler for decorrelating one set of signal samples called the main set from another set called the auxiliary set taken from the same domain. It frequency-translates the signals on their intermediate frequency (i.f.) carrier down close to DC using a local oscillator outside one band edge of the signal and samples the resultant signal at a rate equal to twice the information bandwidth or greater and permits using real rather than complex samples. These samples are then converted to digital information in analog-to-digital converters and are processed digitally at a clock rate equal to twice the information bandwidth or greater. The main signal is processed as above but the auxiliary signal is translated down using the same local oscillator signal and, with the same local oscillator signal phase shifted 90 DEG to obtain an inphase and quadrature signal on the same carrier frequency prior to analog-to-digital conversion. Two real weight digital cancelers are used in cascade to cancel components in the main set that are correlated with those in the auxiliary set by canceling first with the inphase and next with the quadrature component of the auxiliary signal.