Equalization for Compensation of Intersymbol Relationship of Multi-Valued Signaling Using Two-Dimensional Symbol Mapping

This paper introduces a novel equalization scheme for multi-valued data transmission based on inter-symbol relationships using a two-dimensional (2D) symbol map. In highspeed data transmission, the transmission line acts as a low-pass filter and contributes to inter-symbol interference (ISI) at the receiver. The ISI effect, in turn, hinders the realization of high-speed serial-link systems. To mitigate this ISI effect at the receiver, a transmit feed forward equalizer (FFE), mimicking a high-pass filter, is applied to compensate for the transmission characteristics. This study proposes an innovative equalization scheme that focuses on the compensation of inter-symbol relationships in two-dimensional symbol maps for multi-valued signaling. By employing a transmit FFE with low-pass characteristics, the proposed equalizer controls the symbol distribution on a 2D symbol map, leading to the convergence of the variation in symbol distribution. Simulations demonstrate that this low-pass FFE can effectively suppress the surge in high-frequency signals within the transmitted signal, thereby diminishing the ISI impact at the receiver by controlling the symbol distribution on the 2D symbol map. This result underscores the potential of this novel equalization scheme for advancing high-speed multi-valued data transmission systems.