An ILI Mitigating Modulation Scheme for Molecular MIMO Communications

Multiple-input-multiple-output (MIMO) approach is recently proposed to the diffusion-based molecular communication realm in order to enhance communication performance. One of the most promising approaches of molecular MIMO, spatial multiplexing (SMUX), transmits parallel streams of data to achieve an increased throughput. Unfortunately, the performance of SMUX is limited by a high error floor due to severe interlink interference (ILI). Inspired by the relatively more sparse transmission strategy of the pulse-position modulation (PPM) scheme, this study proposes a PPM-based novel SMUX approach to the molecular MIMO literature. In the study, it is shown that the proposed approach combats ILI more effectively than the existing concentration-based SMUX approach and yields promising error performances.