Context-resilient capacity-achieving rateless code for OFDM channels with frequency diversity

Abstract

Recently, rateless codes make a remarkable progress on achieving maximum network performance without incurring CSI feedback overhead, under dynamic contexts with time-varying channels. However, existing rateless codes are only optimal for single-carrier channels, but are far from optimal for multi-subcarrier OFDM channels that are dominantly adopted in modern high-speed wireless networks. In this paper, we propose a new rateless code called SmartCode, which designs and incorporates an implicit sub-carrier differentiation mechanism into a unified rateless framework so as to achieve high performance over OFDM channels. We prove SmartCode's capacity optimality, and demonstrate its performance gain using trace-driven simulations.