IAN F. AKYILDIZ

Systems, methods, and computer-readable media for managing underwater acoustic communications. An automatic network slicing method specifically designed for handling underwater acoustic communications is implemented to enable admission control, routing, and dynamic resource allocation based on service level agreement requirements.

A software-defined modem includes a multi-mode head and a baseband unit. The multi-mode head includes a plurality of mode frontends including, but not limited to acoustic, magnetic induction, radio frequency and optical. Each mode frontend of the plurality of mode frontends is configured to transmit and/or receive communications according to a preset communication mode. The baseband unit is configured to control operation of the multi-mode head. The multi-mode head is configured to simultaneously use one or more communication modes.

Although continuous advances in theoretical modelling of Molecular Communications (MC) are observed, there is still an insuperable gap between theory and experimental testbeds, especially at the microscale. In this paper, the development of the first testbed incorporating engineered yeast cells is reported. Different from the existing literature, eukaryotic yeast cells are considered for both the sender and the receiver, with α-factor molecules facilitating the information transfer. The use of such cells is motivated mainly by the well understood biological mechanism of yeast mating, together with their genetic amenability. In addition, recent advances in yeast biosensing establish yeast as a suitable detector and a neat interface to in-body sensor networks. The system under consideration is presented first, and the mathematical models of the underlying biological processes leading to an end-to-end (E2E) system are …

In this paper, a Universal Underwater Software Defined Modem (UniSDM) architecture is proposed that may operate in different modes (acoustic, magnetic induction, optical and RF), in order to utilize the advantages of each mode and accordingly satisfy the requirements of many latest use cases in underwater communication systems. A detailed description of the novel UniSDM architecture is presented first. The novelty of this architecture is its flexibility, i.e., allowing the designers to produce a device that may include any type of modes operating seamlessly and jointly by exchanging data, control and synchronization. Many challenges, including high system costs and coordination between different modes, are addressed in the paper. Moreover, numerical evaluation is conducted to assess the performance of the proposed UniSDM architecture. Finally, the performance evaluation shows that the utilization of the …

A space-based communications network (100) includes at least one central ground station (116) having a transceiver that is configured to communicate with satellites, such as cube satellites (110). The cube satellites (110) form an ad hoc network of orbital cube satellites, in which each of the cube satellites (110) communicate with each other. One of the cube satellites communicates with the ground station (116). A ground-based control system (1000) communicates with the central ground station (116). The control system (1000) continuously determines a configuration of the ad hoc network (100) and communicates network control information for the cube satellites (110) to maintain communications in the ad hoc network (100). The cube satellites (110) disseminate the network control to each other via the ad hoc network (100).

The UnderWater Acoustic (UWA) communication is the foundation for oceanic information applications. However, existing UWA systems suffer from low data rate problem. Although the Multiple Input Multiple Output (MIMO) scheme is proved to be able to increase channel capacity in many terrestrial scenarios, the high cost and complexity of acoustic MIMO significantly limit its usage. Recently, the acoustic reconfigurable intelligent surfaces (acoustic RIS) concept has been proposed to address the aforementioned problem. In this paper, with the real-world constraints taken into consideration, three key components of the acoustic RIS are designed to realize the underwater RIS concept, including the new acoustic RIS hardware, the ultra-wideband (UWB) beamforming, and practical operation protocol. Specifically, a completely new hardware design of acoustic RIS is first provided, since existing electromagnetic RIS …

Despite its prompt development, Molecular Communications (MC) still fall short of validation, especially at the microscale level. In the Phero-MolCom project, we are working towards the development of a novel testbed to validate cell-to-cell communications during pheromone secretion in yeast cells. In previous work we presented the system under consideration and reported on initial mathematical models focusing on the representation of the receiver (Rx) towards the characterization of the Rx output gene called "Fus1". In this work, we complement this, with the derivation of the channel impulse response (CIR) of the diffusive medium. By appropriately coupling this with the Rx system of Ordinary Differential Equations (ODEs) we form an overall Rx model. For the first time, we report preliminary experimental measurements derived replacing the Fus1 gene inside the cells with a tractable Green Fluorescent Protein …

It is well established that Molecular Communications (MC) fall short of validation, especially at the microscale level for cell to cell communications. We are working towards the development of a new testbed, involving yeast cells facilitating information exchange using pheromones. The testbed will be used to validate an end to end (E2E) communication model of the system involving the transmitter, diffusion channel and receiver dynamics, for system simulation and analysis. In this paper, we report progress towards the development of such a model. We highlight the most important biological processes involved in the considered setup, and how their characterization yields mathematical models different than the ones considered so far in the MC literature. As such, the system poses unique challenges that we aim to address in the near future.

In this work, we focus on the theoretical modeling and experimental evaluation of absorbing metasurfaces mounted on unmanned aerial vehicles (UAVs) as facilitators for secure wireless communication channels. Specifically, we present a network architecture based on UAV-mounted metasurfaces and conduct a comprehensive analysis of its components. Furthermore, by utilizing physical optics, namely the Fresnel-Kirchhoff diffraction formula, we develop a comprehensive path loss model that accurately calculates the scattering of wavefronts from metasurfaces with arbitrary configurations; this model enables the quantification of path loss and mobility effects, including pointing accuracy, misalignment, and UAV flying stability, for both near- and far-field conditions. Finally, experimental measurements are conducted using a state-of-the-art static absorbing metasurface and a commercial UAV in an anechoic chamber …

A computational framework for designing a constellation that includes a plurality of cube satellites (CubeSats) includes an orbit propagation module, a coverage estimation module, a connectivity estimation module and an annealing module. The orbit propagation module receives a plurality of static parameters for the constellation and determines a position vector, a ground track and sub-satellite points for each of the plurality of CubeSats. The coverage estimation module receives the plurality of static parameters for the constellation and estimates Earth coverage for the constellation. The connectivity estimation module receives the plurality of static parameters for the constellation and determines active inter-satellite links (ISL) in the constellation. The annealing module receives input from the orbit propagation module, the coverage estimation module and the connectivity module and employs an annealing algorithm …

Although humans have five basic senses, sight, hearing, touch, smell, and taste, most multimedia systems in current systems only capture two of them, namely, sight and hearing. With the development of the metaverse and related technologies, there is a growing need for a more immersive media format that leverages all human senses. Multisensory media(Mulsemedia) that can stimulate multiple senses will play a critical role in the near future. This paper provides an overview of the history, background, use cases, existing research, devices, and standards of mulsemedia. Emerging mulsemedia technologies such as Extended Reality (XR) and Holographic-Type Communication (HTC) are introduced. Additionally, the challenges in mulsemedia research from the perspective of wireless communication and networking are discussed. The potential of 6G wireless systems to address these challenges is highlighted, and several research directions that can advance mulsemedia communications are identified.

In a method for routing communications through a constellation (100) of a plurality of CubeSats orbiting a planet and responsive to a ground controller, the ground controller determines optimal tunnels (210) that include inter-satellite links (122) between CubeSats by: generating virtual nodes (110); generating the sub-satellite points (120) to correspond to points on a path through each virtual node that CubeSats follow; calculating an inter-satellite link from a sub-satellite point another sub-satellite point during a period from a time of initialization when the first sub-satellite point is at an entry point of the first virtual node until the first sub-satellite point is at an exit point; and generating an information packet describing the optimal tunnel (210) including inter-satellite links (122) that interconnect the sub-satellite points (120). The information packet transmitted from the ground controller to one of the CubeSats and is …

Despite decades-long development, underwater communication systems still cannot achieve high data rates and long communication ranges at the same time (i.e., beyond 1 Mb/s and 1 km). Currently, acoustic communication is the only choice to achieve long distances. However, the inherent low acoustic bandwidth results in extremely low data rates. In this article, the acoustic reconfigurable intelligent surface (RIS) system is proposed to realize high-data-rate long-range underwater communications. Although the EM-based RIS has been widely investigated in terrestrial scenarios in recent years, the underwater acoustic RIS is based on completely different physics principles. Hence, the EM-based terrestrial RISs do not work for underwater acoustic signals. More-over, the long acoustic wave propagation delay, the inherent wideband nature, and the water behavior all impose unique challenges in underwater RIS …

In recent years, many underwater communication applications have been proposed and tested, leading to the Internet of underwater things (IoUT) concept. In the IoUT, sensors may be deployed individually on sea surface and seabed as well as in water at different depths. They also may be integrated into underwater items such as fish, plants, autonomous underwater vehicles (AUVs), remotely operated underwater vehicles (ROVs), and divers. Depending on the application, different connectivity requirements must be satisfied such as data rate, latency, and reliability. However, the underwater communication channels pose a significant challenge to meet these requirements. To accommodate various applications with different service level agreements (SLAs), a multimode (acoustic, optical, and magnetic induction (MI)) communication system is proposed to take advantage of the modes' complementary features …

The active and dynamic controls of the terahertz (THz) waves are highly demanded due to the rapid development of wireless communication systems. Recently, reconfigurable intelligent surface (RIS) has gained significant attention due to their tremendous potential in controlling electromagnetic (EM) waves. Particularly, RIS-based wireless communications are promising for improving the system’s performance by properly designing the reflection coefficient of the unit cell. In this work, we investigate a graphene-based RIS for active and dynamic controls of THz waves. The RIS design consists of a rectangular graphene meta-atoms periodic array placed over a metallic grounded silicon substrate. An equivalent circuit modeling of the RIS design and its solution is provided. The RIS performance is numerically analyzed. The graphene-based RIS achieves nearly 100% reflection in the operational frequency ranging …

Software-Defined Metasurfaces (SDMs) have ad-vanced from basic theoretical ideas to a key enabler for next generation wireless systems. When massively deployed in a wireless environment, they can realize precise, software-defined propagation of signals and wireless channel customizations. A plethora of studies have thoroughly investigated the physical design of the SDMs and their wireless channel engineering capa-bilities. This work introduces a novel architecture and associated processes for integrating SDMs into existing networked wireless systems. First, the integration architecture and the according complex underlying physics of the SDMs are presented. Then the software abstractions are proposed that enable the interaction of the surfaces in a physics-agnostic manner. These software abstractions require an SDM profile to operate in real-time, i.e., a database that accurately describes the capabilities …

Presents the 2022 author/subject index for this issue of the publication.

Non-orthogonal multiple access (NOMA) is a well-accepted technology for future Wi-Fi systems to improve spectral efficiency. NOMA allows an access point (AP) to simultaneously serve multiple devices by splitting the transmit power between them. Using the superposition coding the AP combines signals of different frames with predefined power weights. However, as it is already known, the phase noise caused by hardware imperfections limits the performance of NOMA transmissions. The paper proposes a practical, easy-to-implement, and backward-compatible method to rotate the constellation of the low power signal in order to make it more robust to the phase noise. A mathematical model is developed to find such a rotation angle that minimizes the bit error rate (BER) of the low power frame. A new NOMA Wi-Fi prototype testbed is developed with the new feature of constellation rotation ability, which is used to …

The ability to offer courses over the Internet between remote teacher(s) and students enhances curricula and can improve quality in university work regarding both teaching and research. This is particularly true for small universities that struggle to offer comprehensive curricula due to lack of professors and students. In the spring semester of 2021, the University of Iceland offered a course on the Internet of Things taught by a professor emeritus in Atlanta, Georgia, assisted by a local professor. The lectures were given on Zoom and all assignments and exams were given over the Internet. In this paper, this course’s framework will be described, how it was implemented and what was accomplished. The authors will also share their thoughts on the future of this kind of university work that has to some extent developed due to the Covid situation.

In this work, we present a new approach to Extended Reality (XR), denoted as iCOPYWAVES, which seeks to offer naturally low-latency operation and cost effectiveness, overcoming the critical scalability issues faced by existing solutions. Specifically, iCOPYWAVES is enabled by emerging PWEs, a recently proposed technology in wireless communications. Empowered by intelligent metasurfaces, PWEs transform the wave propagation phenomenon into a software-defined process. To this end, we leverage PWEs to: i) create, and then ii) selectively copy the scattered RF wavefront of an object from one location in space to another, where a machine learning module, accelerated by FPGAs, translates it to visual input for an XR headset using PWE-driven, RF imaging principles (XR-RF). This makes an XR system whose operation is bounded in the physical-layer and, hence, has the prospects for minimal end-to-end …