Flat spiral delay line design with minimum crosstalk penalty

A novel routing scheme for the planar delay line is proposed to minimize the signal distortion and delay time penalty incurred by the backward propagating crosstalk among the sections of delay line. In contrast to the commonly employed serpentine delay line in which the crosstalk noise accumulates synchronously to drastically deteriorate the receiving waveform, the new flat spiral delay line design spreads the crosstalk noise uniformly in time and avoids the crosstalk penalty. A simple wave tracing model is employed to describe qualitatively the spreading mechanism of the new design. Furthermore, quantitative analysis, simulation, and TDT/TDR measurement are performed to validate the advantage and utility of this design.