Superimposed Coding-Based CSI Feedback Using 1-Bit Compressed Sensing

In a frequency division duplex massive multiple input multiple output system, the channel state information (CSI) feedback causes a significant bandwidth resource occupation. In order to save the uplink bandwidth resources, a 1-bit compressed sensing (CS)-based CSI feedback method assisted by superimposed coding (SC) is proposed. Using 1-bit CS and SC techniques, the compressed support-set information and downlink CSI (DL-CSI) are superimposed on the uplink user data sequence (UL-US) and fed back to base station. Compared with the standalone SC-based feedback, the proposed method is shown with analysis and simulation results to improve the UL-US's bit error ratio and the DL-CSI's accuracy, without acquiring exclusive uplink bandwidth resources for DL-CSI feedback.