Ian F. Akyildiz

Akyildiz started his research work on queueing networks models in the early 1980s. His PhD thesis (1984) was entitled “Multiprocessor Systems with Process Communication” where he developed queuing network models to analyze the performance of the multiprocessor systems which were important subject in the early 1980s. In particular, he developed queueing network models for process communication where the buffers were finite and blocking/losses of messages could occur.

His paper [2] was the first which was an original work introducing the duality of the state spaces of queueing networks with blocking/finite buffers versus queueing networks without blocking kind of mapping of state space to each other, and accordingly obtaining exact product form solution for two nodes.

Based on this novel duality concept, Dr. Akyildiz showed in [3] an approximate duality (mapping) of state spaces between queuing networks with and without blocking having arbitrary number of nodes. He then derived the approximate throughput formula and also derived approximate product form solutions in.[4]

He published many other papers on queuing network models.[5] These contributions lead him to obtain the IEEE Fellow rank in 1996,[6] and in particular to performance analysis of computer communication networks.[7]

In 1997 Ian Akyildiz with his colleagues at the YURIE [8] systems designed and implemented the first adaptive forward-error-correction solution on the link layer of their wireless ATM switch providing high reliability in wireless ATM networks with very low bit data rates used in battlefield scenarios. A patent for this solution was obtained in 2006 U.S. Patent 7,058,027.

A technical paper describing the link layer design on this low bit rate wireless ATM switch was published.[9]

The founder of the Yurie Systems, Jeong H. Kim, received the entrepreneur of the year award in 1997 and Yurie Systems was acquired by Lucent for 1 Billion US Dollars in 1998.[8]

Ian Akyildiz significantly contributed to mobility and resource management of 2G and 3G cellular systems in the 90s. He proposed many handoff management, location registration, and paging schemes for the design of 3G and 4G wireless systems, and all of his papers have been published in top notch journals and conferences between 1998 and 2000.[10][11][12]

His paper titled “Mobility Management in Next-Generation Wireless Systems” was invited to be included in Proceedings of IEEE, and is the most cited paper on mobility management in the literature, and became “the” main reading material for the first course on mobile networks in many universities.[13]

His contributions to mobility and resource management gained him the ACM Fellow rank in 1997.[14]

Ian Akyildiz started to use the notion “4G” wireless networks in 1999-2000 through his papers and keynote speeches. He clearly pointed out the requirements for heterogeneous 4G wireless systems, such as anywhere/anytime wireless connectivity with hundreds of Mbps bandwidth per mobile user for both data and multimedia services. Consequently, the first adaptive protocol suite framework for Next Generation Wireless Internet was supported by NSF (National Science Foundation) (2000-2005) NSF #:ANI-0117840.[15]

His early insights on the need to enable a single mobile terminal to seamlessly communicate over heterogeneous wireless access systems such as wireless LANs, 3G cellular networks, and satellite networks are seminal contributions to 4G systems.These ideas were the forerunner of the dynamic spectrum access and cognitive radio networks.

The culmination of his research work on this topic gained him the 2003 ACM SIGMOBILE Outstanding Contribution Award for his "pioneering contributions in the area of mobility and resource management for wireless communication networks", in September 2003.[16]

Akyildiz, in collaboration and with support of NASA, developed several routing algorithms and a novel transport control protocol called TCP Peach [17] to realize practical satellite networks.

He significantly contributed towards the development and realization of high altitude long operation (HALO) networks for providing broadband wireless network access which was implemented by Angel Technologies and Raytheon, exploited by invention disclosures (U.S. Patent 6,756,937) and U.S. Patent 7,027,769). HALO was the forerunner of the current UAVs and Drones and Cubesats research. Couple decades later many countries are working on the directions of the HALO project.

This paper [18] is the first to comprehensively put forward the design principles and system reference model for HALO networks, which is a broadband wireless metropolitan area network with a star topology, whose solitary hub is located in the atmosphere above the service area at an altitude higher than commercial airline traffic.

With the extremely timely publication of the first and most comprehensive roadmap paper on wireless sensor networks,[19] Akyildiz made this new research area known to the entire world. Many researchers, who work on sensor networks, has started by reading his paper. Hence, this publication has received more than 41,000 citations in 20 years. Moreover, this paper received the best tutorial paper award from IEEE Communications society in 2003.[20]

Thanks to his paper, the area has attracted significantly amplified attention and become focus of research and engineering efforts towards realizing wide range of sensor network applications.In 20 years, the research in this area has resulted in billions of dollars of investment from both government and private sector, educated thousands of students, and helped establish hundreds of companies.

Dr. Akyildiz published many pioneering papers on wireless sensor networks. For example, in [21] the first reliable protocol (Event-to-Sink Reliable Transport -ESRT-) was introduced specifically tailored for the unique requirements and characteristics of wireless sensor networks. ESRT was devised based on the extremely novel and yet practical engineering notion of event-to-sink reliability, which leverages the inherent redundancy and spatio-temporal correlation in sensor networks to maximize the network lifetime. ESRT has also been taught in undergraduate and graduate level wireless networking courses at many universities. This work has been implemented in several simulation tools.[22][23]

The pioneering contributions to the field of wireless sensor networks was recognized as the IEEE Computer Society W. Wallace McDowell Award 2011.[24]

He is also the recipient of the IEEE Communications Society Ad Hoc and Sensor Networks Technical Committee (AHSN TC) Technical Recognition Award based on his pioneering contributions to wireless sensor networks and wireless mesh networks.

Akyildiz was one of the first to introduce several advanced and next generation wireless sensor network paradigms and architectures to the research community including sensor and actor networks, multimedia sensor networks, underwater acoustic sensor networks, wireless underground sensor networks, underground magnetic sensor networks, along with the comprehensive list of open research issues and the first novel communication techniques.[25]

Preliminary version of this paper [26] received the best paper award from IEEE GlobeCom 2009 conference.[27]

The paper [28] became the flagpole paper that every researcher reads first as the first initiation into the field of CR networks during the heyday of the CR networks. The paper [29] had major impact as it is the first work which demonstrated the existence of optimal sensing parameters theoretically and developed the framework to support this optimality in real network environments. This paper identified the interference model for CR, well-motivated from the limitation of communication hardware that RF front-ends cannot differentiate between the transmissions of primary and secondary users. It developed a practical spectrum sensing solution, where an optimal observation time and a transmission time are determined to maximize sensing efficiency while satisfying interference limits.

The paper [30] is the first research work that identifies the practical issues and derives possible solutions when extending the CR concept to cellular mobile networks. Specifically, this paper defined two mobility types in the CR cellular networks, user mobility and spectrum mobility.

Akyildiz and his PhD students coined the word “CRAHNs” for the first time in,[31] which is used as a standard terminology by the research community in the meantime. Specifically, this paper looked at the network architectures, where multiple nodes are not associated with a single controller (hence, called CR ad hoc networks or CRAHNs). Many practical networks can be built on top of such distributed architectures for consumer, military and disaster scenarios, with unpredictable spectrum availability. CRAHNS must operate in a dynamic environment where locations, spectrum availability, and neighboring forwarding nodes can change over time, and so are completely different from cellular networks.

All these pioneering contributions lead to receive the prestigious IEEE ComSoc TCCN Recognition Award in 2017 by the IEEE ComSoc Technical Committee on Cognitive Networks (TCCN) with citation "for pioneering contributions to spectrum sensing, spectrum sharing algorithms and communication protocols for cognitive radio networks".

From the nano-device perspective, Akyildiz and his student Jornet proposed for the first time and investigated the use of graphene to develop nano-antennas for electromagnetic (EM) communication in nanonetworks in.[32] This paper showed that, by using a narrow graphene nanoribbon (GNR), an antenna just a few hundreds of nanometers long and tens of nanometers wide could radiate EM waves in the Terahertz (THz) band (0.1-10 THz). This framework is used to characterize the propagation characteristics of Surface Plasmon Polariton (SPP) waves in graphene. This work has become a foundation stone for EM nanonetworks and a US Patent was obtained for this technology in 2017.

Akyildiz and Jornet also proposed a plasmonic nano-transceiver that intrinsically operate in the THz band in where the basic idea is based on the integration of III-V High-Electron-Mobility Transistors (HEMT) with graphene in.[33] In 2016, a US Patent is obtained for this technology.

Akyildiz and his PhD student Jornet also developed very large plasmonic nano-antenna Planar Array with 32x32 (in total of 1024) elements which is called "Ultra-Massive MIMO communication systems" in [34] and a patent was issued for this idea in 2017.

While nanonetworks do not operate based on radio frequency spectrums, they mainly exploit networking paradigms which are fundamentally different yet “wireless” such as molecular communication, where the information is coded and communicated by molecules as explored in [35] and the term “Internet of BioNanoThings: was coined in the paper [36] for the first time.

Akyildiz and his student Pierobon also developed one of the first realistic molecular communication channel models and capacity analysis for molecular communication in.[37][38][39]

Terahertz Band (0.1-10 THz) communication is envisioned as one of the key wireless technologies of the next decade. The THz band will help to overcome the spectrum scarcity problems and capacity limitations of current wireless networks, by providing an unprecedentedly large bandwidth. In addition, THz-band communication will enable a plethora of long-awaited applications ranging from instantaneous massive data transfer among nearby devices in Terabit Wireless Personal and Local Area Networks, to ultra-high-definition content streaming over mobile devices in 6G systems.[40][41]

The THz-band channel was investigated in [42] and the first channel model was developed for this almost unexplored frequency range. The peculiarities of the channel were captured by utilizing radiative transfer theory to account for the absorption from different types of gaseous molecules. In addition, he analytically calculated the channel capacity of the THz band for different medium compositions and power allocation schemes.

Electromagnetic waves undergo multiple uncontrollable alterations as they propagate within a wireless environment. Free space path loss, signal absorption, as well as reflections, refractions, and diffractions caused by physical objects within the environment highly affect the performance of wireless communications. Currently, such effects are intractable to account for and are treated as probabilistic factors. A radically different approach, enabling deterministic, programmable control over the behavior of wireless environments was first introduced in the VISORSURF project.[43]

The key enabler is the so-called HyperSurface tile, a novel class of two-dimensional metamaterials that can interact with impinging electromagnetic waves in a controlled manner. The tiles can effectively re-engineer electromagnetic waves, including steering toward any desired direction, full absorption, polarization manipulation. Multiple tiles coat objects such as walls, furniture, and other objects in indoor and outdoor settings. An external software service calculates and deploys the optimal interaction types per tile to best fit the needs of communicating devices..[44] A patent was acquired in January 2020.

A novel cyber-physical system spanning ground, air, and space, called the Internet of Space Things/CubeSats (IoST) is introduced in.[45][46] IoST expands the functionalities of traditional IoT, by not only providing an always-available satellite backhaul network, but also by contributing real-time satellite-captured information and, more importantly, performing integration of on the ground data and satellite information to enable new applications. The fundamental building block for IoST is a new generation of nano-satellites known as CubeSats, which are augmented with Software Defined Networking (SDN) and Network Function Virtualization (NFV) solutions.