Transversal filters with continuously tapped delay lines (CTT filters)

The properties of common transversal filters are well known. Transversal filters with continuously tapped delay lines have the advantage that they do not show a periodic continuation of the frequency characteristic. Therefore it is not necessary to use an additional filter for suppressing higher frequency components. After an introduction to CTT filter theory the realization of transversal filters with continuous inductive tapping (ICTT filters) is discussed. The description of the practical synthesis of a low-pass filter and a 90° wide-band phase shifter is followed by the interpretation of measured frequency characteristics.