Digital transversal filter

Claim 1

A digital transversal filter comprising: first and second delay lines, each having a data input terminal, a clock input terminal, and a plurality of stages, wherein, for each of the delay lines, at least two adjacent stages of the respective delay line are clocked by a clock signal applied to the respective clock input terminal to shift digital data through the respective delay line, at least selected stages of the delay line each providing a respective output; means for applying a digital data signal to the data input terminal of the first delay line; means for phase shifting the digital data signal to form a phase shifted digital data signal and applying the phase shifted digital data signal to the data input terminal of the second delay line; means for applying first and second clock signals to the clock input terminals of the first and second delay lines, respectively, wherein the first and second clock signals correspond in frequency but differ in phase with respect to one another; means for weighting the outputs of the stages of the first and second delay lines; and means for summing the weighted outputs of the stages of the first and second delay lines to synthesize a summed output; said first mentioned digital data signal having a data clocking rate, said first and second clock signals having a delay line clocking rate, and said data clocking rate being slower than said delay line clocking rate.