Selective Signal Detection with Ligand Receptors Under Interference in Molecular Communications

Molecular Communications (MC) is a bio-inspired wireless communication technique that uses molecules as a means of information transfer among bio-nano devices. In this paper, we focus on the signal detection problem of MC receivers employing receptor molecules to infer the transmitted messages encoded into the concentration of molecules, i.e., ligands. We particularly consider a very common scenario in physiological conditions, where there is non-negligible concentration of interferer molecules in the channel, which have similar binding characteristics with the ligands, and thus, can bind to the receptors, causing substantial interference with the MC signal. We investigate three different maximum likelihood (ML) detection methods based on different observable parameters of the ligand-receptor binding mechanism, which are the instantaneous number of bound receptors and the amount of time the receptors stay unbound or bound within an observation time window. We carry out a comparative analysis to numerically evaluate the performance of the detection methods under different system settings.