Opto-Ultrasonic Communications in Wireless Body Area Nanonetworks

Abstract—Wirelessly interconnected nanorobots, i.e., engineered devices of sizes ranging from one to a few hundred nanometers, are promising revolutionary diagnostic and therapeutic medical applications that could enhance the treatment of major diseases. Each nanorobot is usually designed to perform a set of basic tasks such as sensing and actuation. A dense wireless network of nano-devices, i.e., a nanonetwork, could potentially accomplish new and more complex functionalities, e.g., in-vivo monitoring or adaptive drug-delivery, thus enabling revolutionary nanomedicine applications. Several innovative communication paradigms to enable nanonetworks have been proposed in the last few years, including electromagnetic communications in the terahertz band, or molecular and neural communications. In this paper, we propose and discuss an alternative approach based on establishing intrabody opto-ultrasonic communications among nanorobots. Optoultrasonic communications are based on the optoacoustic effect, which enables the generation of high-frequency acoustic waves by irradiating the medium with electromagnetic energy in the optical frequency range. We first discuss the fundamentals of nanoscale opto-ultrasonic communications in biological tissues, and then we model the generation, propagation, and detection of opto-ultrasonic waves. I

Intra-Body Communications for Nervous System Applications: Current Technologies and Future Directions

The Internet of Medical Things (IoMT) paradigm will enable next generation healthcare by enhancing human abilities, supporting continuous body monitoring and restoring lost physiological functions due to serious impairments. This paper presents intra-body communication solutions that interconnect implantable devices for application to the nervous system, challenging the specific features of the complex intra-body scenario. The presented approaches include both speculative and implementative methods, ranging from neural signal transmission to testbeds, to be applied to specific neural diseases therapies. Also future directions in this research area are considered to overcome the existing technical challenges mainly associated with miniaturization, power supply, and multi-scale communications.Comment: https://www.sciencedirect.com/science/article/pii/S138912862300163

Nano-Communication for Biomedical Applications: A Review on the State-of-the-Art From Physical Layers to Novel Networking Concepts

We review EM modeling of the human body, which is essential for in vivo wireless communication channel characterization; discuss EM wave propagation through human tissues; present the choice of operational frequencies based on current standards and examine their effects on communication system performance; discuss the challenges of in vivo antenna design, as the antenna is generally considered to be an integral part of the in vivo channel; review the propagation models for the in vivo wireless communication channel and discuss the main differences relative to the ex vivo channel; and address several open research problems and future research directions

Characterisation of Skin-based THz Communication Channel for Nano-scale Body-centric Wireless Networks

PhDIn pursuit of enhancing the capabilities of healthcare diagnostics and monitoring, the electromagnetic spectrum has been utilized efficiently from the MHz up to THz and beyond. The era of smart phones, wearable devices and on-body networks have unfolded plethora of health applications with efficient channel communication mechanisms, faster data transfer rates and multi-user functionalities. With the advancement in material fabrication and spectroscopic techniques, a new realm of healthcare nanodevices have emerged with immense potential to garner in-depth information of the human body, real-time of tissue morphology, molecular features, hydration level and atmospheric water vapour on channel parameters. In addition to this, engineered skin substitute models: 2D collagen and 3D organotypics, are investigated to address the importance of individual biological features comprising of water dynamics and cell culture, affecting the channel parameters. The experimental results of various tissue samples, skin substitutes and numerical evalua-tion of channel parameters can be used to further improve the communication capabilities of in-body nanonetworks. The original contributions on characterization of skin substitutes can be applied to study various health conditions, effects of drugs and skin ageing on a molecular level. The results presented in this thesis, foresee an increasing demand in skin substitute models due to their biological flexibility and control according to desired medical applications. monitoring and tackle medical emergencies. A collection of these devices with sensing capabilities together form a nanonetwork performing computing tasks such as storage, actuation, data transfer and communication. The thesis brings forth the analysis and optimization of channel parameters; such as pathloss and molecular noise temperature, when the proposed in-body nanodevices communicate amongst each other in the terahertz (THz) range. The novel contribution of the work is mapping the optical properties of human skin by bringing together the measurement of various skin tissues and its influence on channel parameters. In the later part of the thesis, emphasis is given on the individual biological entities of the tissue contributing to channel parameters, such as collagen as an abundant protein, variation in fibrous extra-cellular matrix due to fibroblast cells and amalgamation of different layers; namely, epidermis and dermis of the skin. Recently proposed graphene-based antennas resolve the cumbersomeness of existing medical devices by drastically reducing its size to a few hundreds of nanometres. These biocompatible nanodevices focus on exchanging the intricate details of the human body via nanoscale electromagnetic communication in the terahertz domain of the spectrum. The thesis aims to investigate the material properties of skin tissues with terahertz time do-main spectroscopy and numerically evaluate the channel parameters for in-body nanoscale networks that potentially would form an essential part of a hierarchical body-centric communication network extending from inside the human body to a wider community network. The results are presented in regards to the complexity of human tissue as a channel medium. The measured refractive index and absorption coefficient data is applied to numerically calculate channel pathloss and molecular noise temperature. The results provide a real-time analysi

Characterisation of the In-vivo Terahertz Communication Channel within the Human Body Tissues for Future Nano-Communication Networks.

PhDBody centric communication has been extensively studied in the past for a range of frequencies, however the need to reduce the size of the devices makes nano-scale technologies attractive for future applications. This opens up opportunities of applying nano-devices made of the novel materials, like carbon nano tubes (CNT), graphene and etc., which operate at THz frequencies and probably inside human bodies. With a brief introduction of nano-communications and review of the state of the art, three main contributions have been demonstrated in this thesis to characterise nano-scale body-centric communication at THz band: • A novel channel model has been studied. The path loss values obtained from the simulation have been compared with an analytical model in order to verify the feasibility of the numerical analysis. On the basis of the path loss model and noise model, the channel capacity is also investigated. • A 3-D stratified skin model is built to investigate the wave propagation from the under-skin to skin surface and the influence of the rough interface between different skin layers is investigated by introducing two detailed skin models with different interfaces (i.e.,3-D sine function and 3-D sinc function). In addition, the effects of the inclusion of the sweat duct is also analysed and the results show great potential of the THz waves on sensing and communicating. • Since the data of dielectric properties for biological materials at THz band are quite scarce, in collaboration with the Blizard Institute, London, UK, different human tissues such as skin, blood, muscle and etc. are planned to be measured with the THz Time Domain Spectroscopy (THz-TDS) system at Queen Mary University of London to enrich the database of electromagnetic parameters at the band of interest. In this chapter, collagen, the main constitution of skin was i mainly studied. Meanwhile, the measured results are compared with the simulated ones with a good agreement. Finally, a plan for further research activities is presented, aiming at widening and deepening the present understanding of the THz body-centric nano-communication channel, thus providing a complete characterisation useful for the design of reliable and efficient body centric nano-networks. iiChina Scholarship Council Queen Mary University of Londo

Fibroblasts cell number density based human skin characterization at THz for in-body nanonetworks

Institute of Bioengineering Ph.D. Scholarship, QMUL and Parts of this publication specifically, Sections 3 and 4 were made possible by NPRP grant # 7-125-2-061 from the Qatar National Research Fund (a member of Qatar Foundation)

Analytical Modeling of a Communication Channel Based on Subthreshold Stimulation of Neurobiological Networks

The emergence of wearable and implantable machines manufactured artificially or synthesized biologically opens up a new horizon for patient-centered health services such as medical treatment, health monitoring, and rehabilitation with minimized costs and maximized popularity when provided remotely via the Internet. In particular, a swarm of machines at the scale of a single cell down to the nanoscale can be deployed in the body by the non-invasive or minimally invasive operation (e.g., swallowing and injection respectively) to perform various tasks. However, an individual machine is only able to perform basic tasks so it needs to exchange data with the others and outside world through an efficient and reliable communication infrastructure to coordinate and aggregate their functionalities. We introduce in this thesis Neuronal Communication (NC) as a novel paradigm for utilizing the nervous system \emph{in vivo} as a communication medium to transmit artificial data across the body. NC features body-wide communication coverage while it demands zero investment cost on the infrastructure, does not rely on any external energy source, and exposes the body to zero electromagnetic radiation. n addition, unlike many conventional body area networking techniques, NC is able to provide communication among manufactured electronic machines and biologically engineered ones at the same time. We provide a detailed discussion of the theoretical and practical aspects of designing and implementing distinct paradigms of NC. We also discuss NC future perspectives and open challenges. Adviser: Massimiliano Pierobo