SYSTEM AND METHODS FOR EFFICIENT DIGITIZATION IN HYBRID FIBER-COAXIAL NETWORKS

摘要

An analog signal processor includes a sampling unit configured to (i) filter, in the frequency domain, a received time domain analog signal into a low-frequency end of a corresponding frequency spectrum, (ii) sample the filtered analog signal at a frequency substantially higher than the low-frequency end, and (iii) spread quantization noise over an expanded Nyquist zone of the corresponding frequency spectrum. The processor further includes a noise shaping unit configured to shape the spread quantization noise out of the low-frequency end of the corresponding frequency spectrum such that the filtered analog signal and the shaped quantization noise are substantially separated in the frequency domain, and a quantization unit configured to apply delta-sigma modulation to the filtered analog signal using at least one quantization bit, and output a digitized bit stream that substantially follows the amplitude of the received time domain analog signal.