Two enhanced decision feedback equalizers for 10Gb/s optical communications

In this work, two unique decision feedback equalizers (DFE) for use in 10 Gb/s optical communications are presented. These equalizers are effective at cancelling post-cursor ISI as well as pre-cursor ISI without the use of a feed-forward equalizer (FFE). The removal of the FFE equalizer is desirable as it is very expensive from a chip real-estate perspective. The synthetic transmission lines used to achieve the analog delay in FFE filters also suffer from performance issues such as limited bandwidth, impedance mismatches, and nonlinearities which degrade the efficacy of the filter. The proposed filter structures will be evaluated via numerical simulation, and a comparison with standard FFE/DFE techniques will be made.