16 research outputs found
Extended master equation models for molecular communication networks
We consider molecular communication networks consisting of transmitters and
receivers distributed in a fluidic medium. In such networks, a transmitter
sends one or more signalling molecules, which are diffused over the medium, to
the receiver to realise the communication. In order to be able to engineer
synthetic molecular communication networks, mathematical models for these
networks are required. This paper proposes a new stochastic model for molecular
communication networks called reaction-diffusion master equation with exogenous
input (RDMEX). The key idea behind RDMEX is to model the transmitters as time
series of signalling molecule counts, while diffusion in the medium and
chemical reactions at the receivers are modelled as Markov processes using
master equation. An advantage of RDMEX is that it can readily be used to model
molecular communication networks with multiple transmitters and receivers. For
the case where the reaction kinetics at the receivers is linear, we show how
RDMEX can be used to determine the mean and covariance of the receiver output
signals, and derive closed-form expressions for the mean receiver output signal
of the RDMEX model. These closed-form expressions reveal that the output signal
of a receiver can be affected by the presence of other receivers. Numerical
examples are provided to demonstrate the properties of the model.Comment: IEEE Transactions on Nanobioscience, 201
Comunicaci贸n Molecular: Retos y oportunidades
La comunicaci贸n molecular permite el env铆o de informaci贸n a trav茅s de mol茅culas u otras part铆culas a escala de nan贸metros a micr贸metros. La misma posee limitaciones como: degradaci贸n de las part铆culas en el medio acuoso durante la propagaci贸n y retardo de la se帽al de informaci贸n recibida debido al movimiento browniano de las part铆culas. En este art铆culo se describen los fundamentos m谩s relevantes de un sistema de comunicaci贸n molecular incluyendo retos, limitaciones y aplicaciones en la que esta tecnolog铆a tendr铆a un impacto relevante. Se presentan los aspectos significativos del canal de comunicaciones, tipos de modulaci贸n y herramientas de modelaje de sistemas de comunicaci贸n molecular
The design and performance analysis of diffusive molecular communication systems
Molecular Communications (MC) is an increasingly attractive technique to enable the networking of nano-machines by utilising molecules as the information carrier. The molecular diffusion can be described by either the movement of individual molecules or the molecular concentration. Accordingly, two kinds of diffusive MC systems have been modelled in previous literature. On the basis of these studies, the aim of this Ph.D. is to refine these two models, to implement functional transmission techniques and technologies, and to investigate the corresponding system performance. To fulfil this target, the whole Ph.D. is divided into two stages. During each stage, specific tasks have been accomplished, each contributing to the overarching research field of diffusive MC systems.
In the first stage, an MC system model, named as the Model-I, is established and enhanced by focusing on the motion of individual molecules. The performance has been evaluated by both deriving mathematical expressions and implementing MATLAB simulations. Based on the Model-I, a distance estimation scheme has been proposed. Compared with existing methods, this new scheme is more accurate and less time-consuming. Moreover, five Stop-and-Wait Automatic Repeat reQuest (SW-AQR) protocols have been implemented on the Model-I. Results reveal that all these SW-ARQ schemes work well and can be beneficial under different circumstances.
In the second stage, another MC system model, named as the Model-II, is established and refined with information conveyed by the molecular concentration. Both theoretical derivations and MATLAB simulations are provided to analyse the system reliability. Laid on this foundation, two distance measurement methods have been proposed and shown to be suitable for the Model-II. Additionally, to solve the long-range MC problem, relaying schemes have been applied by deploying a relay node between the source and target nano-machines. The performance improvement of each scheme is also illustrated respectively