Intrinsic MIMO Particle Communication Channel with Random Advection

TL;DR

This paper explores how advection in molecular communication channels enables pulse preservation and receiver diversity, leading to improved detection performance and laying groundwork for advanced MIMO molecular communication systems.

Contribution

It demonstrates the role of advection in enabling pulse-based modulation and receiver diversity, providing a framework for future MIMO molecular communication research.

Findings

Advection preserves pulse shape, enabling higher-order modulation.

Distributed receivers observe distinct signal realizations, offering diversity gain.

Receiver combining improves detection, especially at low-to-moderate SNR.

Abstract

In this work, receiver diversity in advection-dominated diffusion-advection channels is investigated. Strong directed flow fundamentally alters the communication-theoretic properties of molecular communication systems (MC). Specifically, advection preserves the temporal ordering and shape of transmitted pulses, enabling pulse-based and higher-order modulation schemes that are typically infeasible in purely diffusive environments. Focusing on a single transmitter and a single type of information molecule, it is demonstrated that spatially distributed receivers can observe distinct realizations of the same transmitted signal, giving rise to diversity gain. Several receiver combining strategies are evaluated and shown to improve detection performance compared to single-receiver operation, particularly in low-to-moderate signal-to-noise ratio (SNR) regimes. The results provide a structured framework for understanding receiver-side diversity in molecular communication, highlighting the role of advection as a key enabler for reliable pulse-based signaling. This perspective establishes a foundation for future studies on advanced modulation, joint equalization and detection, and multi-molecule MIMO extensions that can further enhance the performance and physical applicability of MC systems.