Message Passing Receivers for Generalized Media-Based Modulation Signals

Abstract

We consider generalized media-based modulation (GMBM), where transmit antennas and radio frequency (RF) mirrors (which are parasitic elements placed near the transmit antennas as digitally controlled scatterers) are indexed simultaneously to convey information bits. We develop low complexity receiver algorithms for the detection of high-rate, large-dimension GMBM signals. Message passing-based detection is a promising low-complexity approach. The elements in a GMBM transmit vector are interdependent. Message passing with a multi-layering approach is proposed to take care of this dependency. The proposed multi-layering approach decouples the dependencies through the addition of new layers and constraints that account for the antenna activation and RF mirror activation patterns. The proposed message passing detection with multi-layering, termed as multi-layered message passing detection, is shown to outperform message passing detection without multi-layering and constraints. In addition to exploiting multi-layering, the channel hardening property of large MIMO channels is exploited for GMBM signal detection and channel estimation. The algorithm based on this approach is termed as multi-layered channel hardening-exploiting message passing algorithm. The proposed algorithms scale well in complexity and achieve good bit error performance in high-rate, large-dimension GMBM systems.