Digital filter with attenuation and phase equalising - consists of non-recursive group transit time equaliser, and attenuation equaliser

摘要

The digital filter reduces the scanning frequency of an A/D converter and equalises the attenuation and phase of an analog filter in front of the converter. The digital filter consists of a decimation filter and an equaliser, coupled in cascade. The equaliser (EL) is of a non-recursive group transit time type and contains an attenuation equaliser (EA) for the attenuation of the analog filter (AF), the decimation filter (DEZ) and the group transit time equaliser. If the digital filter increases the converter scanning frequency, it consists of an interpolation filter with an equaliser, connected in cascade. The group transit equaliser is typically a transversal filter. USE/ADVANTAGE - For signal processing, with small number of multipliers and subsequent low cost.