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Energy efficiency analysis of multi-hop mobile diffusive molecular communication

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Abstract

Diffusive molecular communication (DMC), in which molecules are used to deliver information in diffusion channel, is one of the most prominent systems in nanonetworks. In particular, the research on end-to-end mobile DMC system is even more challenging. In this paper, we investigate the energy efficiency of multi-hop mobile DMC system. First, the energy model for this system is proposed based on the mobilities of transmitter nanomachine (TN), relays and receiver nanomachine (RN). Then the mathematical expressions of total energy consumption and throughput are derived. Furthermore, the energy efficiency which is defined as the throughput per unit energy consumption is analyzed. Finally, the numerical results show that the parameters including the diffusion coefficients and velocities of mobile TN, relays and RN, the initial distance of each hop, the number of molecules emitted in each time slot by TN and relays, and each time slot duration have different impacts on the energy efficiency. How to set these system parameters can be used to provide guidelines for designing energy efficient multi-hop mobile DMC system.

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... In Cheng et al, 17 an amplify-and-forward scheme is proposed which involves multiple relay nodes transferring a message from the transmitter to its intended receiver in a three-dimensional environment. Similarly, in Cheng et al, 18 an energy efficiency analysis is performed for a multi-hop network with mobile nodes. Such researches show that relaying can be an effective strategy for transferring messages over longer distances in biological nanonetworks. ...
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Molecular communication is a novel nanoscale communication paradigm, in which information is encoded in messenger molecules for transmission and reception. However, molecular communication is unreliable and has highly varying long propagation delays mainly due to the stochastic behavior of the freely diffusing molecules. Thus, it is essential to analyze its delay characteristics, as well as the tradeoff between the rate and delay, in order to reveal the capabilities and limitations of molecular information transmission in nanonetworks. In this paper, first, a new messenger-based molecular communication model, which includes a nanotransmitter sending information to a nanoreceiver, is introduced. The information is encoded on a polyethylene molecule, CH3 (CHX)n CH2F, where X stands for H and F atoms representing 0 and 1 bits, respectively. The emission of the molecules is modeled by puffing process which is inspired by the alarm pheromone release by animals in dangerous situations. In this work, the rate-delay characteristics of this messenger-based molecular communication model are explored. Then, a Nano-Relay is inserted in the model, which XOR's the incoming messages from two different nanomachines. Performance evaluation shows that indeed, a simple network coding mechanism significantly improves the rate given delay of the system, and vice versa.
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The ability of engineered biological nanomachines to communicate with biological systems at the molecular level is anticipated to enable future applications such as monitoring the condition of a human body, regenerating biological tissues and organs, and interfacing artificial devices with neural systems. From the viewpoint of communication theory and engineering, molecular communication is proposed as a new paradigm for engineered biological nanomachines to communicate with the natural biological nanomachines which form a biological system. Distinct from the current telecommunication paradigm, molecular communication uses molecules as the carriers of information; sender biological nanomachines encode information on molecules and release the molecules in the environment, the molecules then propagate in the environment to receiver biological nanomachines, and the receiver biological nanomachines biochemically react with the molecules to decode information. Current molecular communication research is limited to small-scale networks of several biological nanomachines. Key challenges to bridge the gap between current research and practical applications include developing robust and scalable techniques to create a functional network from a large number of biological nanomachines. Developing networking mechanisms and communication protocols is anticipated to introduce new avenues into integrating engineered and natural biological nanomachines into a single networked system. In this paper, we present the state-of-the-art in the area of molecular communication by discussing its architecture, features, applications, design, engineering, and physical modeling. We then discuss challenges and opportunities in developing networking mechanisms and communication protocols to create a network from a large number of bio-nanomachines for future applications.