Non-uniform Quantization and RUM for Optimizing Implementation of Real-Time FIR Equalization in Short-Reach Optical Links

We propose a low-complexity equalization scheme with non-uniform quantization and rotational update mechanism (RUM). The scheme is verified in implementation of DDLMS equalization for 92-Gbaud 10-km offline and 14.7456-Gbaud 25-km FPGA-based real-time PAM4 IM/DD experimental transmission, results show up to 99.5% multiplications (DSP resource usage) are reduced comparing to normal DDLMS equalizer. A large number of equivalent taps can be achieved based on several active taps.