Adaptive Decision Feedback Equalization for Multi-Gbps Serial Links: Challenges and Opportunities

Data-intensive applications such as video streaming, cloud computing, and virtual presence devices require data to be transmitted among chips, modules, and chassis via serial copper channels at tens of giga-bit-per-second (Gbps), as shown in Table 1. The data rate of these links is limited by inter-symbol interference (ISI) arising from channel impairment such as finite bandwidth, reflection, and crosstalk [1]. Al-though low-loss channels and low-reflection vias/connectors are highly desirable, they are costly. Combating the effect of channel imperfection by means of channel equalization is proven to be the most robust, effective, and economical. This editorial briefly examines difficulties encountered in design of adaptive decision feedback equalizers for multi-Gbps serial links. In addition, it browses through recent developments that overcome these difficulties and challenges that are yet to be conquered.