Feedback considered beneficial: Exploring frequency diversity in full-duplex rateless codes

Abstract

Recently, rateless codes have displayed a promising paradigm for rate adaptation. They enable the sender to transmit packets with a fixed data rate, and the receiver to decode the packets with a data rate comparable to its channel condition. Therefore, rateless codes can achieve higher wireless throughput than the fixed rate codes, especially over time-varying channels. However, as wireless multicarrier techniques become essential technologies in current communication systems, the design of rateless code exposes a critical problem. That is, it is not able to leverage frequency diversity introduced by multi-carrier techniques, which will degrade the achievable data rate. Motivated by this, we propose a Full Duplex Rateless (FDR) code in frequency domain. It aims to take advantage of the frequency diversity and fine-grained feedback to achieve the “most appropriate” data rate on every single subcarrier in a multicarrier communication system. Extensive simulations have been conducted to verify the effective of FDR code, and the results show that FDR code achieves up to 6.5× data rate over the fixed-rate LDPC codes, and 2.3× data rate over rateless Spinal code.