The design of continuous-time linear equalizers using model order reduction techniques

Abstract

The peaking gain and the peaking frequency of a continuous-time linear equalizer (CTLE) are considered key design parameters to improve link performance. Many high-speed signaling standards define peaking gain as specification of the transmitter or receiver equalizer to achieve their target data rates. Peaking gain and frequency aside, the zeros play a major role in shaping the frequency response of the CTLE. These zeros closely relate to the poles of the channel to be equalized; thus their locations need to be selected with care when optimizing CTLE parameters. This paper describes a non-iterative method of selecting the equalizer parameters by first matching the frequency response of the CTLE to the inverse loss profile of the channel. The approach uses model order reduction (MOR) techniques to determine the zeros of the CTLE from the channel characteristics.