A General Analytical Approximation to Impulse Response of 3-D Microfluidic Channels in Molecular Communication

In this paper, the impulse response for a 3-D microfluidic channel in the presence of Poiseuille flow is obtained by solving the diffusion equation in radial coordinates. Using the radial distribution, the axial distribution is then approximated accordingly. Since Poiseuille flow velocity changes with radial position, molecules have different axial properties for different radial distributions. We, therefore, present a piecewise function for the axial distribution of the molecules in the channel considering this radial distribution. Finally, we lay evidence for our theoretical derivations for impulse response of the microfluidic channel and radial distribution of molecules through comparing them using various Monte Carlo simulations.Comment: The manuscript is submitted to IEEE: Transactions on Nanobioscienc

Diffusion-controlled interface kinetics-inclusive system-theoretic propagation models for molecular communication systems

Inspired by biological systems, molecular communication has been proposed as a new communication paradigm that uses biochemical signals to transfer information from one nano device to another over a short distance. The biochemical nature of the information transfer process implies that for molecular communication purposes, the development of molecular channel models should take into consideration diffusion phenomenon as well as the physical/biochemical kinetic possibilities of the process. The physical and biochemical kinetics arise at the interfaces between the diffusion channel and the transmitter/receiver units. These interfaces are herein termed molecular antennas. In this paper, we present the deterministic propagation model of the molecular communication between an immobilized nanotransmitter and nanoreceiver, where the emission and reception kinetics are taken into consideration. Specifically, we derived closed-form system-theoretic models and expressions for configurations that represent different communication systems based on the type of molecular antennas used. The antennas considered are the nanopores at the transmitter and the surface receptor proteins/enzymes at the receiver. The developed models are simulated to show the influence of parameters such as the receiver radius, surface receptor protein/enzyme concentration, and various reaction rate constants. Results show that the effective receiver surface area and the rate constants are important to the system’s output performance. Assuming high rate of catalysis, the analysis of the frequency behavior of the developed propagation channels in the form of transfer functions shows significant difference introduce by the inclusion of the molecular antennas into the diffusion-only model. It is also shown that for t > > 0 and with the information molecules’ concentration greater than the Michaelis-Menten kinetic constant of the systems, the inclusion of surface receptors proteins and enzymes in the models makes the system act like a band-stop filter over an infinite frequency range.The Sentech Chair in Broadband Wireless Multimedia Communications (BWMC) at the University of Pretoria and the Department of Trade and Industry (DTI) THRIP Program.http://www.hindawi.com/journals/asp/am201

Communication (MoNaCom) Molecular Transport in Microfluidic Channels for Flow-induced Molecular Communication

Abstract—Fluid flow inside microfluidic channels can alleviate excessive dispersion and delay in diffusion-based molecular communication and lead to the emergence of Flow-induced Molecular Communication (FMC). To develop communication techniques for FMC, analysis of molecular transport by flow, i.e., convection, inside microfluidic channels is essential. In this paper, molecular transport, i.e., concentration propagation, is studied for FMC in rectangular microfluidic channels. First, solution of flow velocity inside rectangular microfluidic channels is presented. Then, impulse response and transfer function are determined for a point source based on the flow velocity, diffusion constant, channel cross-section, and length parameters. Frequency and phase responses for concentration propagation in rectangular microfluidic channels with different cross-section and length parameters are revealed via numerical results. I