Multiple-access channel capacity of diffusion and ligand-based molecular communication

Molecular communication is a novel paradigm that uses molecules as an information carrier to enable nanomachines to communicate with each other. The two major components of a diffusion-based molecular communication are diffusion in the medium and the ligand-reception. In this paper, using the principles of diffusion theories and natural ligand-receptor binding mechanisms in biology, we first develop and present model for the molecular single-access channel. Then, we derive the capacity expressions of the molecular single-access channel. Furthermore, we extend it to multiple-access channel in which multiple transmitters communicate with a single receiver. The objective of this paper is to study the capacity of multiple-access channel which is effected by the parameters of diffusion channel and ligand-receptor binding mechanisms. The numerical results show that the overall channel capacity is restricted by the physical parameters of diffusion channel and ligand-receptors and some different characteristics are presented in multiple-access channel scenario comparing with single-access channel scenario.