SIN(X)/X COMPENSATION CIRCUITRY

摘要

PURPOSE: A digital circuit is provided to compensate peculiar sin(x)/x function of a digital to analog converter in a digital remodulation system. CONSTITUTION: A digital remodulation system typically includes a digital to analog converter(104) and a correction apparatus(202). The digital to analog converter(104) has an inherent undesirable sin(x)/x frequency response. Digital remodulated signals are typically high frequency and thus not conducive to sin(x)/x pre-correction prior to digital to analog conversion. The correction apparatus(202) previously corrects the sin(x)/x roll off of the digital to analog converter(104) in the digital signal path prior to the digital modulator(204) which precedes the digital to analog converter(104). This apparatus(202) corresponds to a cascading of spectrally symmetric and anti-symmetric transversal filters designed to compensate a relatively small portion of the frequency response of the resulting analog signal.