Nano Communication Networks最新文献

Molecular communication via diffusion (MCvD) schemes are limited to short distances between the nanomachines due to the transmitted signal becoming rapidly weaker as the distance increases. Additionally, these schemes are very often affected by high inter-symbol interference, which makes them prone to errors, thus leading to unreliability. In this paper, a novel system is proposed, which aims to enhance the received signal shape and the overall performance of MCvD schemes over longer distances. A relay nanomachine is introduced between the transmitter–receiver pair, which collects the first portion of the molecules emitted from the transmitter and keeps them for some delay time $\tau$, then releases them towards the receiver, such that the delayed and non-delayed portions of the molecules arrive almost at the same time. In this way, the signal’s strength is enhanced by pointing more molecules towards the intended direction, that is, the receiver node. An analytical model for the optimal relaying scheme is proposed, alongside with an optimization problem to find the most advantageous $\tau$ value. Comparison between the proposed scheme and the conventional single-input single-output scenario is provided by means of analytical and computer simulation results, showing a promising improvement in error rates when the relay is introduced.

Internet of Nano-Things (IoNT) is an expansion of the Internet of Things (IoT) with the capacity to monitor extremely fine-grained events with sensors on a scale ranging from one to a hundred nanometers. One major challenge for this type of communication paradigm is to determine the identity of the transmitting nodes and the events. From previous works, we know that different amount of energy is discharged in the environment from different events. This motivates us to propose an energy-neutral event recognition framework using pulse position modulation in which the event information is transmitted by the sensors that use the energy harvested from the event. In this framework, we use pulse position to identify transmitting nodes communicating with a single receiver. However, using this approach, we can also encode the identity of multiple receivers when a single node communicates with them without employing an addressing scheme in IoNT networks. In both cases, the energy observation of the received pulse helps in identifying the event type. The feasibility of the proposed framework is demonstrated by a large number of numerical simulations which include terahertz channels. We find that the proposed framework achieves 99% accuracy for detecting ten different event types at a distance of 30 mm.

This article investigates a novel electrophoretic molecular communication framework that utilizes a time-varying electric field, which induces time-varying molecule velocities and in turn improves communication performance. For a sinusoidal field, we specify favorable signal parameters (e.g., phase and frequency) that yield excellent communication-link performance. We also analytically derive an optimized field function by formulating an appropriate cost function and solving the Euler–Lagrange equation. In our setup, the field strength is proportional to the molecular velocity; we verify this assumption by solving the Basset–Boussinesq–Oseen equation for a given time-varying electric field (forcing function) and examining its implications for practical physical parameterizations of the system. Our analysis and Monte-Carlo simulation results demonstrate that the proposed time-varying approach can significantly increase the number of information-carrying molecules expected to be observed at the receiver and reduce the bit-error probability compared to the constant field benchmark.

Deoxyribonucleic acid (DNA) comprises four nucleotides and twenty amino acids (a combination of nucleotides) that generate living organisms’ structures. These discrete components, jointly with DNA characteristics and functions, allow understanding the DNA as a digital component. Thus, when DNA is considered an organic digital memory, it becomes a compelling data storage medium given its superior density, stability, energy efficiency, longevity, and lack of foreseeable technical obsolescence compared with conventional electronic media. Furthermore, various challenging experiments (described in this work) have demonstrated that digital information (regardless of its type, i.e., text, audio, video, image) can be written in DNA, stored, and accurately read. On the other hand, since nature has designed DNA with a tremendous capacity to store information, compression techniques (also described in this work) are required for appropriately managing this enormous quantity of information. Finally, we discuss a bit’s representation for nucleotides and amino acids due to DNA digital characteristics.

Silicon photonics has developed rapidly in recent years, which has received widespread attention due to the fact that it can overcome the bandwidth bottleneck in optical communications. This paper mainly introduces the key applications of silicon photonics in the field of communication. Through a detailed description of optical transceiver modules in the coherent optical communication and data center, the advantages of silicon optical technology in the field of communication are introduced, such as high speed, low power consumption, high bandwidth and cost-effective. The problems of fabrication, packaging, light source integration and related devices in the current applications of silicon photonics are briefly analyzed. In the future, silicon photonics technology is expected to have better application prospects in long-distance transmission, big data communication and other communication applications.

This paper presents a tunable terahertz (THz) two-port graphene patch antenna having isolation between the ports of the order of 40 dB over the whole range of tunability. This antenna could either be used in self-diplexing mode or as a multi-input–multi-output (MIMO) antenna with pattern diversity that can support simultaneous-transmit-and-receive (STAR) mode of operation with its high port-level isolation. The antenna structure through numerical analysis is optimized to provide the highest isolation and good impedance matching. A detailed analysis of the antenna modes is carried out to get insight into the impedance matching and radiation mechanism. An electrical equivalent circuit is proposed for the MIMO graphene patch antenna to get a better understanding of its operation. Furthermore, a linear regression model is introduced to help in determination of the chemical potentials of the two graphene radiators for different frequencies of MIMO operation.

In this paper, a compact Super Wide Band (SWB) four element multiple-input-multiple-output (MIMO) antenna having an overall dimension of 125 $\mu$m$\times 125\mu$m is presented for application in Terahertz (THz) frequency spectrum. This SWB MIMO antenna configuration consists of orthogonally placed four coplanar waveguide (CPW) fed half elliptical patch antennas with connected ground planes. Three types of fractal curves are suitably applied on this MIMO configuration to obtain enhanced impedance bandwidth and good isolation between antenna elements. The proposed design exhibits an impedance bandwidth ($S_{11}$$\le$ −10 dB) from 0.72 THz to 10 THz (ratio impedance bandwidth 13.89:1) and an isolation more than 20 dB between all four antenna elements is obtained over the entire band of operation. Stable radiation characteristics with moderate amount of gain are also observed The other MIMO performance parameters like Envelop Correlation Coefficient (ECC), Diversity Gain (DG), Channel Capacity Loss (CCL) and Total Active Reflection Coefficient (TARC) are also within acceptable limit over the entire THz frequency of operation. The proposed design consists of more number of antenna elements with relatively smaller physical dimension compared to the existing SWB MIMO antenna designs available in literature in THz frequency range. Therefore, this proposed MIMO antenna design can be used for THz applications in future beyond the fifth generation (B5G) technology.

In this paper, a fuzzy-logic-based fault detection system is designed for a medical Internet of Nano Things architecture. The goal of this system is to detect the root cause and severity of the faults occurred in the in-body nanonetwork. Since nanomachines have very limited capabilities, the sampled data from the in-body nanonetwork is sent to cloud servers by means of an on-body micro-gateway. The fuzzy fault detection system was designed based on two well-known methods including Mamdani and Takagi–Sugeno–Kang (TSK) fuzzy systems. The performance of the proposed approach is evaluated on a theoretical model of medical in-body nanonetwork from the literature through in silico study. This nanonetwork includes eleven types of nanomachines which cooperate with each other within the arterial wall and interact with low-density lipoprotein (LDL), drug and signaling molecules in order to prevent the formation and development of Atherosclerosis plaques. Any fault in these nanomachines can highly take negative effect on treatment efficiency. The results of computer simulation and comparative study on 37 atherosclerosis patients demonstrate how the proposed approach could successfully detect the root cause and severity of the faults occurred in the nanonetwork.