Abstract-Terahertz Band: The Last Piece of RF Spectrum Puzzle for Communication Systems

Hadeel Elayan, Osama Amin, Basem Shihada, Raed M. Shubair, Mohamed-Slim Alouini

https://arxiv.org/abs/1907.05043

Ultra-high bandwidth, negligible latency and seamless communication for devices and applications are envisioned as major milestones that will revolutionize the way by which societies create, distribute and consume information. The remarkable expansion of wireless data traffic that we are witnessing recently has advocated the investigation of suitable regimes in the radio spectrum to satisfy users' escalating requirements and allow the development and exploitation of both massive capacity and massive connectivity of heterogeneous infrastructures. To this end, the Terahertz (THz) frequency band (0.1-10 THz) has received noticeable attention in the research community as an ideal choice for scenarios involving high-speed transmission. Particularly, with the evolution of technologies and devices, advancements in THz communication is bridging the gap between the millimeter wave (mmW) and optical frequency ranges. Moreover, the IEEE 802.15 suite of standards has been issued to shape regulatory frameworks that will enable innovation and provide a complete solution that crosses between wired and wireless boundaries at 100 Gbps. Nonetheless, despite the expediting progress witnessed in THz wireless research, the THz band is still considered one of the least probed frequency bands. As such, in this work, we present an up-to-date review paper to analyze the fundamental elements and mechanisms associated with the THz system architecture.

Abstract-Characterising THz propagation and intrabody thermal absorption in iWNSNs

Hadeel Elayan,  Raed M. Shubair, Josep M. Jornet,

http://ieeexplore.ieee.org/document/8319581/

Nanosized devices operating inside the human body will eventually facilitate transformative health monitoring and diagnosis systems. The interconnection of these implantable nanosensors forms an in vivo wireless nanosensor network (iWNSN), which allows autonomous data transmission and enables sensing, coordination, and control among its entities. In specific, with the development of miniature plasmonic signal sources, antennas and detectors, wireless communications among nanodevices points towards the terahertz band (0.1-10 THz) as a suitable platform and feasible wireless range to initiate intrabody communication. In this study, a rigorous channel model for intrabody communication in iWNSNs is developed. The total path loss is computed by taking into account the contribution of the spreading of the propagating wave, molecular absorption from human tissues, as well as scattering from both small and large body particles. The presented model is further complemented by investigating the photo-thermal interactions which arise from absorption at the THz frequency band. The aforementioned study which analyzes the propagation of electromagnetic signals inside the human body is fundamental to assess the feasibility of the THz frequency band, determine the requirements and controlling parameters of a THz intrabody system as well as highlight the health issues correlated with operating at such frequencies.

Abstract-Photothermal Modeling and Analysis of Intra-body Terahertz Nanoscale Communication

Hadeel Elayan, Pedram Johari,  Raed M. Shubair, Josep Miquel Jornet

http://ieeexplore.ieee.org/document/8052555/

Wireless communication among implanted nanobiosensors will enable transformative smart health monitoring and diagnosis systems. The state of the art of nano-electronics and nano-photonics points to the Terahertz (THz) band (0.1-10 THz) and the optical frequency bands (infrared, 30-400 THz, and visible, 400-750 THz) as the frequency range for communication among nano-biosensors. Recently, several propagation models have been developed to study and assess the feasibility of intrabody electromagnetic (EM) nanoscale communication. These works have been mainly focused on understanding the propagation of EM signals through biological media, but do not capture the resulting photothermal effects and their impact both on the communication as well as on the body itself. In this paper, a novel thermal noise model for intra-body communication based on the diffusive heat flow theory is developed. In particular, an analytical framework is presented to illustrate how molecules in the human body absorb energy from EM fields and subsequently release this energy as heat to their immediate surroundings. As a result, a change in temperature is witnessed from which the molecular absorption noise can be computed. Such analysis has a dual benefit from a health as well as a communication perspective. For the medical community, the presented methodology allows the quantization of the temperature increase resulting from THz frequency absorption. For communication purposes, the complete understanding of the intra-body medium opens the door towards developing modulations suited for the capabilities of nano-machines and tailored to the peculiarities of the THz band channel as well as the optical window.

Abstract-Terahertz Channel Model and Link Budget Analysis for Intrabody Nanoscale Communication

Hadeel Elayan,  Raed M. Shubair,  Josep M. Jornet, Pedram Johari,

http://ieeexplore.ieee.org/document/7955066/

Nanosized devices operating inside the human body open up new prospects in the healthcare domain. In vivo wireless nanosensor networks (iWNSNs) will result in a plethora of applications ranging from intrabody health-monitoring to drug- delivery systems. With the development of miniature plasmonic signal sources, antennas and detectors, wireless communications among intrabody nanodevices will expectedly be enabled at both the Terahertz Band (0.1-10 THz) as well as optical frequencies (400-750 THz). This result motivates the analysis of the phenomena affecting the propagation of electromagnetic signals inside the human body. In this paper, a rigorous channel model for intrabody communication in iWNSNs is developed. The total path loss is computed by taking into account the combined effect of the spreading of the propagating wave, molecular absorption from human tissues, as well as scattering from both small and large body particles. The analytical results are validated by means of electromagnetic wave propagation simulations. Moreover, this paper provides the first framework necessitated for conducting link budget analysis between nanodevices operating within the human body. This analysis is performed by taking into account the transmitter power, medium path loss, and receiver sensitivity where both the THz and photonic devices are considered. The overall attenuation model of intrabody THz and optical frequency propagation facilitates the accurate design and practical deploy- ment of iWNSNs.