Effect of Molecular Noise in Diffusion-Based Molecular Communication

In this paper, we consider the Langevin model for Brownian motion in a fluid medium. As a molecule travels through a fluid medium, its continuous collision with the molecules of the fluid can be considered as a continuous random force acting on the molecule. This force is the source of uncertainty in the position of the molecule and can be treated as a noise. The mathematical model for such noise is proposed in this work. The role of finite life expectancy of molecules and inter-symbol interference is also considered. Closed form expressions for the probability of error and the channel capacity are derived considering a binary communication scheme. Furthermore, our results illustrate the impact of these parameters on the performance of molecular communication techniques.