Group‐delay‐insensitive linear equaliser for reducing eye‐skew in PAM‐4 receivers.

A novel group‐delay‐insensitive linear equaliser (GDILE) is proposed to reduce the eye‐skew in four‐level pulse amplitude modulation (PAM‐4) receivers. With a cross‐coupled positive‐feedback degeneration network, the proposed GDILE employs additional pole and zero into its transfer function to reduce the group‐delay variation with frequency. Simulation results shows a 40 Gbit/s PAM‐4 receiver that employs a GDILE that can reduce the eye‐skew by 73% compared with the conventional linear equaliser with a modest increase of power consumption. [ABSTRACT FROM AUTHOR]