Modeling Duct Flow for Molecular Communication

TL;DR

This paper investigates the applicability of simplified flow models in molecular communication within complex 3D environments, deriving analytical responses and assessing the impact of advection-only transport on communication performance.

Contribution

It provides analytical expressions for channel responses in non-uniform flow regimes and evaluates the overlooked advection-only transport's effect on symbol error rate.

Findings

Analytical expressions validated by simulations.

Flow regime applicability depends on Peclet number and distance.

Advection-only transport significantly impacts communication performance.

Abstract

Active transport such as fluid flow is sought in molecular communication to extend coverage, improve reliability, and mitigate interference. Flow models are often over-simplified, assuming one-dimensional diffusion with constant drift. However, diffusion and flow are usually encountered in three-dimensional bounded environments where the flow is highly non-uniform such as in blood vessels or microfluidic channels. For a qualitative understanding of the relevant physical effects inherent to these channels, based on the Peclet number and the transmitter-receiver distance, we study when simplified models of uniform flow and advection-only transport are applicable. For these two regimes, analytical expressions for the channel impulse response are derived and validated by particle-based simulation. Furthermore, as advection-only transport is typically overlooked and hence not analyzed in the molecular communication literature, we evaluate the symbol error rate for exemplary on-off keying as performance metric.