Digital filterl for A=D converter frequency reduction - has equaliser of non-recursive group transit time type, and decimating filter for attenuation

摘要

The filter reduces the scanning frequency of an A/D converter and equalises the attenuation and phase of an analog filter in front of the A/D converter. The filter consists of a decimation-filter and a digital equaliser, connected in cascade. The equaliser (EL) is of a non-recursive group transit time type. The decimation filter (DEZ) equalises the attenuation of the analog filter (AF) and of the group transit time equaliser. If the filter increases the A/D converter scanning frequency, it consists of an interpolsation filter and the equaliser, coupled in cascade. The interpolation filter takes over the function of the decimation filter. USE/ADVANTAGE - For signal processing, needing only small signal and coefft. word lengths.