Distributed Circuit Techniques for Equalization of Short Multimode Fiber Links

• Main Author: Ng, George Chung Fai
• Other Authors: Chan Carusone, Anthony
• Format: Others
• Language: en_ca
• Published: 2008
• Subjects: equalizers; infinite impulse response; traveling wave filter; transversal filter; CMOS; integrated circuits; 0544
• Online Access: http://hdl.handle.net/1807/11156

Electronic dispersion compensation (EDC) of intermodal dispersion on short multimode fiber (MMF) links operating at 40 Gb/s is investigated through system level simulations and the design of two analog integrated circuit (IC) equalizers. System simulations using worst-case MMF link models show the effectiveness of a 2-tap baud spaced finite impulse response (FIR) equalizer for 40-m links, and a second-order Tbaud/2 infinite impulse response (IIR) equalizer for 50-m links. An IIR filter topology suitable for IC implementation with double loops and multiple delay sections was developed. The 2-tap FIR and the IIR equalizer are implemented in UMC 0.13-um and STM 90-nm CMOS processes respectively. Measurements demonstrate the FIR and IIR equalizing 38-Gb/s and 30-Gb/s cable channels respectively. To the author's knowledge, the double-loop multi-delay IIR equalizer is the first integrated traveling-wave equalizer utilizing poles as a means of frequency boosting, contrasting the conventional FIR technique of utilizing zeros.