Toward localization in terahertz-operating energy harvesting software-defined metamaterials

Abstract

Software-Defined Metamaterials (SDMs) show a strong potential for advancing the engineered control of electromagnetic waves. As such, they are envisioned to enable a variety of exciting applications, among others in the domains of smart textiles, high-resolution structural monitoring, and sensing in challenging environments. Many of the applications envisage deformations of the SDM structure, such as its bending, stretching or rolling, which implies that the locations of metamaterial elements will be changing relative to one another. In this paper, we argue that if the metamaterial elements would be accurately localizable, this location information could potentially be utilized for enabling novel SDM applications, as well as for optimizing the control of the elements themselves. To enable their localization, we assume that these elements are controlled wirelessly through a Terahertz (THz)operating nanonetwork. We consider the elements to be energy-constrained, with their sole powering option being to harvest environmental energy. By means of simulation, we demonstrate sub-millimeter accuracy of the two-way Time of Flight (ToF)-based localization, as well as high availability of the service (i.e., consistently more than 80% of the time), which is a result of the low energy consumed during localization. Finally, we qualitatively characterize the latency of the proposed localization service, as well as outline several challenges and future research directions.

Localization in power-constrained Terahertz-operating software-defined metamaterials

“…As mentioned, localization in SDMs is a topic that did not receive any attention from the community to date. That is with an exception of our previous work [16] (n.b., a conference paper), where we outlined the concept of two-way ToF-based trilateration for enabling localization in THzoperating power-constrained SDMs. In this work, we extend our initial findings by, among others, evaluating the proposed approach with a substantially higher level of realism (e.g., by considering an SDM-specific and frequencydependent channel model) and along a more exhaustive set of system parameters (e.g., by considering the effects of the number and constellation of localization anchors and mobility patterns of the nanonodes), as well as by utilizing a more comprehensive set of performance metrics (i.e., localization accuracy and availability, and latency of reporting location estimates).…”

In-body Bionanosensor Localization for Anomaly Detection via Inertial Positioning and THz Backscattering Communication

“…With their low-power and low heat-radiation wireless communication, backscattering tags perfectly suit the integration into BNSs to operate in in-body applications. So far, their feasibility and promising accuracy has only been demonstrated for localization problems on the macro-level [22], [23]. El-Absi et al [22] exploited backscattered THz signals to extract the round-trip time-of-flight (RToF) between nodes and anchors to determine the distance between them.…”

“…However, the network in [22] was of static nature and thus does not fit an in-body scenario. The second approach [23] attempted to localize software-defined metamaterial (SDM) elements by utilizing THz backscattering communication for frequencies of 300 GHz to 10 THz. The localization relied on trilateration by exploiting distance estimates from RToF measurements between nanonodes and controllers.…”