Adaptive detection and ISI mitigation for mobile molecular communication

Current studies on modulation and detection schemes in molecular communication mainly focus on the scenarios with static transmitters and receivers. However, mobile molecular communication is needed in many envisioned applications, such as target tracking and drug delivery. Until now, investigations about mobile molecular communication have been limited. In this paper, a static transmitter and a mobile bacterium-based receiver performing random walk are considered. In this mobile scenario, the channel impulse response changes due to the dynamic change of the distance between the transmitter and the receiver. Detection schemes based on fixed distance fail in signal detection in such a scenario. Furthermore, the intersymbol interference (ISI) effect becomes more complex due to the dynamic character of the signal which makes the estimation and mitigation of the ISI even more difficult. In this paper, an adaptive ISI mitigation method and two adaptive detection schemes are proposed for this mobile scenario. In the proposed scheme, adaptive ISI mitigation, estimation of dynamic distance and the corresponding impulse response reconstruction are performed in each symbol interval. Based on the dynamic channel impulse response in each interval, two adaptive detection schemes, concentration-based adaptive threshold detection (CATD) and peak-time-based adaptive detection (PAD), are proposed for signal detection. Simulations demonstrate that, the ISI effect is significantly reduced and the adaptive detection schemes are reliable and robust for mobile molecular communication

Coverage and throughput analysis for FRET-based mobile molecular sensor/actor nanonetworks

Nanonetworks are envisaged to expand the capabilities of single nanomachines by enabling collaboration through communication between them. Förster Resonance Energy Transfer (FRET) observed among fluorescent molecules is a promising means of high-rate and reliable information transfer between single fluorophore-based nanoscale molecular machines. Recent theoretical studies have underlined its practicality for mobile ad hoc nanonetworks consisting of functionalized fluorescent molecules. In this study, we focus on the spatial characteristics of FRET-Based Mobile Molecular Sensor/Actor Nanonetworks (FRET-MSAN) by investigating the network performance in terms of communication coverage, network throughput and information propagation rate through extensive Monte Carlo simulations. The effect of fundamental system parameters related to FRET and to the mobility of the network nodes on the network performance is revealed. The results of the simulations indicate that the throughput and propagation rate as a function of distance from the information source are well-fitted by exponential curves. We also observe that the impact of FRET mechanism suppresses the effect of Brownian motion of network nodes on the exciton mobility. © 2014 Elsevier Ltd