Patent ID: 6968353

Claim:
An interpolator which interpolates a digital input signal sequence (x(k)) at interpolation instants (Δt/T r1 ) prescribed by a control signal (S) for the purpose of generating a digital output signal sequence (y(k)), comprising: a first half band filter, which interpolates the input signal sequence (x(k)) in each case in a center of each sampling period (T r1 ) of the input signal sequence (x(k)) and thus generates an intermediate signal sequence (z(k)); a first polyphase filter, which interpolates the intermediate signal sequence (z(k)) at an instant (t L ) which lies in a predetermined pattern of possible interpolation instants before the interpolation instant (Δt/T rl ) prescribed by the control signal(S); a second polyphase filter, which interpolates the intermediate signal sequence (z(k)) at an instant (t R ) which lies in a predetermined pattern of possible interpolation instants after the interpolation instant (Δt/T rl ) prescribed by the control signal (S); and a linear interpolation filter, which carries out a linear interpolation between interpolation values (y PPF — L (k), y PPF — R (k)) of the first and second polyphase filters in a manner dependent on a position of the interpolation instant (Δt/T rl ) prescribed by the control signal (S) relative to the interpolation instants (t L , t R ) of the first and second polyphase filters.