Non-decimated to decimated switchable equalisation filter - has two filter parts whose coefficients are changed to change filter mode of operation by coefficient readjusting circuit.

摘要

The adaptable equalisation filter includes two filter parts (TF1, TF2) whose filter coefficients (C-5...C5 or C-5/2...C5/2) can be changed by a coefficient readjusting circuit (CORR). The filter can operate in both non-decimated mode, for which the sampling rate corresponds to the symbol rate (fs) (baud-spaced) and a decimated mode where the sampling rate corresponds to a sampling theorem (half-baud-spaced) . The wiring between the coefficient multipliers (31...41) of the filter parts and the part correlators (80...90) of the coefficient readjustment circuit is invariant, w.r.t. the switching between operating modes. ADVANTAGE - Requires fewer switches or change-over switches, requires less chip area and has reduced power loss.