From Nano-Communications to Body Area Networks: A Perspective on Truly Personal Communications

Abstract

This article presents an overview of future truly personal communications, ranging from networking inside the human body to the exchange of data with external wireless devices in the surrounding environment. At the nano- and micro-scales, communications can be realized with the aid of molecular mechanisms, Forster resonance energy transfer phenomenon, electromagnetic or ultrasound waves. At a larger scale, in the domain of Body Area Networks, a wide range of communication mechanisms is available, including smart-textiles, inductive- and body-couplings, ultrasounds, optical and wireless radio transmissions, a number of mature technologies existing already. The main goal of this article is to identify the potential mechanisms that can be exploited to provide interfaces in between nano- and micro-scale systems and Body Area Networks. These interfaces have to bridge the existing gap between the two worlds, in order to allow for truly personal communication systems to become a reality. The extraordinary applications of such systems are also discussed, as they are strong drivers of the research in this area.

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VOLUME XX, 2020 1
Date of publication xxxx 00, 0000, date of current version xxxx 00, 0000.
Digital Object Identifier 10.1109/ACCESS.2020.Doi Number
From Nano-Communications to Body Area
Networks: A Perspective on Truly Personal
Communications
PAWEL KULAKOWSKI1, KENAN TURBIC2, (Member, IEEE), and LUIS M. CORREIA2, (Senior
Member, IEEE)
1AGH University of Science and Technology, Krakow, Poland
2INESC-ID/Instituto Superior Técnico, University of Lisbon, 1000-029 Lisbon, Portugal
Corresponding author: Pawel Kulakowski (e-mail: kulakowski@kt.agh.edu.pl).
This work was developed within the framework of the COST Action CA15104, IRACON. It was also partially supported by the Polish
Ministry of Science and Higher Education with the subvention funds of the Faculty of Computer Science, Electronics and
Telecommunications of AGH University of Science and Technology.
ABSTRACT This paper presents an overview of future truly personal communications, ranging from
networking inside the human body to the exchange of data with external wireless devices in the surrounding
environment. At the nano- and micro-scales, communications can be realized with the aid of molecular
mechanisms, Förster resonance energy transfer phenomenon, electromagnetic or ultrasound waves. At a
larger scale, in the domain of Body Area Networks, a wide range of communication mechanisms is available,
including smart-textiles, inductive- and body-couplings, ultrasounds, optical and wireless radio
transmissions, a number of mature technologies existing already. The main goal of this paper is to identify
the potential mechanisms that can be exploited to provide interfaces in between nano- and micro-scale
systems and Body Area Networks. These interfaces have to bridge the existing gap between the two worlds,
in order to allow for truly personal communication systems to become a reality. The extraordinary
applications of such systems are also discussed, as they are strong drivers of the research in this area.
INDEX TERMS Body Area Networks, Communication Interfaces, Nano-Networks, Molecular
Communications, Personal Communications.
I. INTRODUCTION
The several successive generations of mobile cellular and
wireless communications have been aiming at a single goal:
to provide connectivity to people at their own pleasure. It
started with the famous “anytime, anywhere” motto in the 1st
Generation of voice-only mobile cellular communications,
and since then it has evolved to the provision of data and
multimedia everywhere and with a decreasing delay. In
addition to satisfying the anticipated data rate requirements,
the incoming 5thGeneration aims at two other key goals: to
reduce transmission latency and to substantially increase
network capacity. These two goals are not improving the
direct user’s experience, but rather enabling machine-based
applications and services. So, somehow, the further
evolution of mobile and wireless communications has to
eventually address the truly personal dimension of
communications, i.e., the exchange of information within,
around, and outside the body.
Body area networks (BANs), accommodating such
communication scenarios, have been gaining considerable
attention recently. However, for truly personal
communication systems, one needs to encompass nano-
networks [1], to allow for the exchange of information
among devices inside the human body, by exploiting
mechanisms at the cellular and molecular levels. At the nano-
scale, communications are performed by using molecules or
molecular structures with specific properties, such as photo-
active fluorophores or channelrhodopsins, antibodies
(proteins), moving bacteria or waves of ions at different
scales, as shown in Fig. 1. Of course, this ultrawide range of
communication mechanisms introduces a number of
challenges, including those related to power supply,
propagation delay, and throughput, among many others.
These challenges need to be addressed from the technical
aspect, for example, design of antennas, electronics,
interfaces, materials, software, etc., but also from the socio-

VOLUME XX, 2020 2
psychological one, as the deployment of these systems will
highly depend on acceptance by society.
On the other hand, since these systems will be an integral
part of the body, they may truly change people’s lives.
Imagine if one’s thoughts could be picked up and sent to
another person, without the need for a verbal explanation, or
if one’s body could detect cancerous tissues, heart and brain
function anomalies, and warn physicians well in advance of
a heart attack, seizure, or other complications. While these
examples stretch one’s imagination, the potential of these
personal systems is extraordinary.
This paper addresses these truly personal communication
systems, with the focus on the aspects of integration of nano-
communication systems into a large-scale communication
network. A brief overview of nano- and BAN
communication technologies is provided, and the potential
mechanisms that can be used to establish interfaces in
between the two are discussed. The latter is the main
contribution of this paper, as interfaces are addressed by
taking a perspective different from the typical one, by
underlining their crucial role in making these systems work.
Thus, beyond the reviewing of techniques in nano-networks
and BANs, the paper brings together insights into physics,
biotechnology and optogenetics, explaining new
mechanisms that can be exploited for creating interfaces
between the networks at the different scales.
The rest of this paper is organized as follows. Potential
applications are discussed in Section II, and the components
of the foreseen personal network are addressed in the
following sections, in an increasing scale. Nano- and micro-
scale communications inside the body are discussed by
reviewing the most promising mechanisms in Section III,
followed by an overview of the main communication
scenarios and enabling technologies in current BANs in
Section IV. The potential interfaces between networks of
different scales are discussed in Section V, finishing with the
main conclusions in Section VI.
II. APPLICATIONS
Establishing communications between nano-, micro- and
macro-networks, when possible, opens a vast area of new
applications, stretching beyond the ones envisioned for nano-
networks alone. The pivotal change is the fact that nano-
networks may be contacted and controlled from the macro-
scale world during the whole time of their operation.
The largest group of potential applications is related to
medical diagnostics and surgery. One may imagine a
diagnostic system composed of nano-particles deployed in the
human tissue or the vascular system [2], [3]. Data gathered by
the system can be transmitted outside the body to a medical
doctor, through BAN connections, for real time analysis.
Similarly, nano-machines could be used to perform remote
surgery, with the surgeons having access to the collected data
and steering their actions. One can easily envisage other
applications in healthcare, encompassing patient monitoring,
localized drug delivery, aging care, etc.
Data storage is another area that can greatly benefit from
nano- and molecular-networks, considering the exponentially
increasing amount of data mankind is producing.
Deoxyribonucleic and ribonucleic acid (DNA and RNA)
strands, which keep the human genome in nucleotide chains,
are extremely effective in data storage. In theory, each
nucleotide can keep 2 bits of information, as there are 4
different nucleotides both in DNA and RNA strands. It was
recently shown that information can be artificially stored and
retrieved in DNA very efficiently, keeping on average 1.57
bits per nucleotide, which corresponds to an impressive
density of 215 petabytes per gram of DNA [4].
These systems could also comprise smart uniforms for fire
fighters, police, and soldiers in battlefields, with the embedded
sensors capable of measuring the body's vital signals or detect
bullet wounds, hence, being essential for the safety of their
users. Nano-sensors operating inside one’s body could allow
for quick diagnostics, localization and precise classification of
FIGURE
1.
Scale of communication mechanisms and
devices.

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the tissue damage in case of injury, allowing for a quick
reaction of a medical team, e.g., rescuing a soldier from the
battlegrounds, and ultimately making the difference between
life and death.
Many applications can be envisaged in sports as well,
especially for training of high-performance athletes and
monitoring of the fitness-related activities, including the
measurement of different physiological parameters, e.g., heart
rate, energy consumption, fat percentage, body water content,
etc. The measurement and display of real-time information
and/or the control of follow-up reports may lead sports to a
new level of professional well-being and safety.
Backed by the power of business and commerce, the
entertainment industry is one of the potential technology
drivers. On the one hand, requirements may not be as strict as
in the previous areas (a person’s life is not at stake), but on the
other hand, the required scale may represent a great challenge.
Some more futuristic applications include people
“thinking” directly to a network. While some direct brain-
computer interaction has already been achieved previously
[5], [6], nano-communications could be the key factor for a
real breakthrough progress. Assuming that human nerve cells
can be connected via a nano-network to an external BAN, and
then to other networks, a person could send thoughts and
emotions directly through the network, without the need to
type or vocalize them. This would represent a real integration
of a person with a network, and a merge of the Internet of
Things with the Internet of Nano-Things [7], which could
represent the embodiment of truly personal communications,
and the direction for the development of future wireless
networks.
Finally, the enhancement of advanced human-computer
interfaces will enable people to have access to a wide range of
truly personal information. These systems will revolutionize
healthcare as one knows it today, by advancing diagnostics
and disease prevention far beyond today’s possibilities, but
also fundamentally change many other areas.
III. NANO-COMMUNICATION MECHANISMS
There are a few distinct approaches to communications at the
nano-scale, the main ones being:
1. FRET-based, where communications occur at distances
of nanometers.
2. Molecular, which is a group of distinct phenomena at the
scale of nano- to micrometers.
3. Electromagnetic (EM), where devices can communicate
at the millimeter scale.
4. Ultrasonic photoacoustic, over distances of the order of
a hundred micrometers.
The estimated parameters for the communication mechanisms
discussed in this section are summarized in Table 1.
The first approach is based on the Förster resonance energy
transfer (FRET) phenomenon, which allows for energy to pass
between molecules in a non-radiative manner. The
unconventional nano-transmitter and receiver are in this case
two neighboring molecules, rather than artificial devices. The
transmitting molecule, excited to a high energy state by an
external radiation or a chemical reaction, passes its energy to
the receiving one. This transfer happens quite fast, i.e., within
nanoseconds, and at nanometer distances, i.e., between
molecules at most 20 nm apart. In terms of communication,
FRET can be used for a binary “on-off” modulation, where bit
‘1’ is realized by a FRET transfer, while ‘0’ corresponds to no
transfer [8]. One should note that FRET occurs only between
spectrally matched molecules, i.e., when the nano-
transmitter’s emission spectrum overlaps the nano-receiver’s
absorption one. However, if needed, the spectral gap between
the molecules can be filled in by using phonon-assisted energy
transfer [9].
In addition to a very limited range, FRET is not particularly
reliable. Instead of sending a signal to the receiver, the
transmitting molecule may lose its energy by emitting a
photon. This problem can be overcome by employing
multiple-input multiple-output FRET, with multiple
molecules at both communication sides, Fig. 2, thereby
improving communication reliability by diversity, similarly to
conventional radio communications [10]. One should also
mention that signal routing in FRET-based networks is
feasible, if molecules with specific properties are used, such
as photo-switched fluorophores, quenchers or proteins of
changeable shape [11].
The second approach exploits biological mechanisms,
operating at scales ranging from nano- to micrometers [12].
Communications in cells of living organisms occur in various
ways, with information carriers again not being EM waves, but
groups of molecules, hence, the name molecular
TABLE 1. Estimated parameters for nano- and micro-communication mechanisms.
Mechanism
Range
Throughput
Signal speed
Technology maturity
FRET
15 nm
25 Mbit/s
1 m/s
laboratory experiments
Calcium wave propagation
300 µm
(1)
1 bit/s
30 µm/s
laboratory experiments
Polymers
a few µm
a few kbit/s
below 1 mm/s
theoretical analysis
Molecular motors
up to 50 µm
1 cargo/motor
(2)
1 µm/s
laboratory experiments
Bacteria
about 1 mm
up to 1 Mbit/bacterium
up to 20 µm/s
laboratory experiments
Nano
-
rods
10 mm
128 kbit/nanorod
up to 20 µm/s
laboratory experiments
Neurons 1 m 1 kbit/s up to 120 m/s laboratory experiments
EM
-
based micro
-
devices
5 mm
500 kbit/s
1.5 × 10
8
m/s
(3)
theoretical analysis
(1) assuming a favorable alignment of cells where calcium ions propagate, usually the range is smaller.
(2) cargoes might be liposomes or vesicles containing DNA strands, quantum dots or micro-fabricated silicon.
(3) for human blood; it might differ in other tissues depending on the tissue refractive index; in graphene, it is 100 times
sma
ller.

VOLUME XX, 2020 4
communications [13], [14], the great advantage being their
bio-compatibility, as these mechanisms naturally occur in
biological organisms.
One of the most widely considered communication
mechanisms is molecular diffusion. The commonly analyzed
information carrier is by waves of propagating calcium ions
[15], [16], information being coded as the concentration of
calcium ions emitted by a cell. The ions themselves are small
particles, i.e., 100 to 200 pm in size, that can propagate over
distances up to 300 µm, assuming a favorable alignment of
living cells for diffusion [17], [18]. Some larger particles, as
polymers, can be broadcasted by diffusion as well, carrying
information coded in their modified structure. For example,
bits ‘0’ and ‘1’ can be coded by modifying polymers with
either hydrogen or fluorine atoms [19]. Since the diffusion
process is slow, with the average velocity of calcium ions not
exceeding 30 µm/s, some diffusion acceleration methods,
such as flow assisted propagation [20], are also considered.
Other molecular communication approaches include those
based on molecular motors, which are about 100 nm long
structures, such as kinesins or dyneins, carrying information
on an RNA strand or a sequence of peptides in a vesicle [21].
These motors ensemble wired-like communications, as they
move along protein tracks called micro-tubules, thus, being
much slower (about 1 µm/s of propagation speed), but far
more reliable than the other approaches of its class.
The size of the largest molecular carriers is of the order of a
micrometer, and active transportation techniques may be used
(in contrast with passive diffusion). Bits can be encoded in a
DNA strand of a plasmid located inside a bacterium or
attached to a catalytic nano-motor. The bacterium, such as
Escherichia coli, then travels using the force of its flagella. The
catalytic nano-motors, i.e., usually gold and platinum nano-
rods, can exploit chemical energy from the environment by
participating in chemical reactions, e.g., catalyzing the
formation of oxygen [22].
As a communication medium for nano- and micro-scale,
neurons, i.e., nerve cells, should be mentioned. The size of
these cells varies strongly from micrometers to even 1 or 2 m
(the longest ones, e.g., from a toe to the brain). The anatomy
of neurons is a well-studied topic. They receive signals when
molecules called neurotransmitters reach specific receptors
located on a neuron membrane, which triggers the opening of
ion channels on the membrane and causes some ions flow in
and out of the neuron changing its inner electrical potential.
The resulting electrical impulse (called action potential)
travels inside the neuron till its end (called synapse), where it
initiates releasing small vesicles with neurotransmitters that,
via diffusion, can reach and activate another neuron or a motor
cell.
Impulses in neurons travel very fast, comparing with other
molecular mechanisms, reaching 120 m/s if the neuron is
covered with myelin, which is a specific insulating material
[23]. This makes neurons the fastest propagation medium
among the considered molecular mechanisms, however, as in
the case of molecular motors, signals propagate in one
direction only. The achievable throughput is limited by the
refractory period, which is the time after the action potential
propagation when the neuron does not respond to any
stimulation. The refractory period is at least 1 ms, which
means that the upper bound for throughput in a single neuron
is about 1 kbit/s, assuming a temporal coding of1 bit per neural
impulse (1: an impulse, 0: no impulse [24]).
The third approach is based on the idea of miniaturization
of the existing EM communication techniques. The attainable
scale of devices is about 10 µm, which is larger than the one
in molecular networks. Therefore, the tiny size of micro-scale
device restricts the communication frequency to the THz band.
The use of lower and more favorable frequencies in between
0.1 and 10 THz is enabled by graphene-based antennas
capable of efficiently radiating EM waves in this band [25],
[26], [27], with the resonant frequencies being two orders of
magnitude lower than those for the metallic antennas of the
same size. On the surface of these materials, EM waves
propagate as surface plasmon polaritons [28], and under
specific conditions, their velocity can be even 100 times lower
FIGURE 2. Nano-communication mechanisms. (a) FRET signal transfer among fluorophores mounted on antibodies.(b) Propagation of Ca2+ ion
waves among cells.(c) Bacterium moving with the force of its flagella.(d) Molecular motor m oving along a micro-tubule carrying RNA data in a
vesicle.

VOLUME XX, 2020 5
than in vacuum. In such circumstances, the wavelengths of
THz waves are in order of 1 µm.
Communications at the THz band are associated with many
challenges, the high propagation losses inside body tissues
limiting the range to only a few millimeters. In addition to a
high path loss, due to the spreading wave front, the rich water
content of the blood and body tissues yields extremely high
frequency-selective molecule absorption losses [29], resulting
in path loss exceeding 120 dB for distances of a few
millimeters [30]. The resonance of molecules excited by THz
waves results in the conversion of EM energy into kinetic one,
being absorbed by the molecule and lost from the
communication perspective. On the other hand, the imposed
variations of molecules result in EM radiation in the same
frequency band, manifesting itself as non-white noise with
power magnitude depending on the communication distance
and on the number of molecules in between transmitting and
receiving antennas [29]. Moreover, as molecular absorption is
conditioned by the presence of a signal in the medium, the
corresponding noise results in pulse spreading, and sufficient
separation between successive pulses has to be ensured to
prevent interference, Time Spread On-Off Keying (TS-OOK)
having been proposed as a suitable coding scheme [31].
By exploiting the same mechanisms, the emerging
plasmonic antennas also enable optical transmission in infra-
red and visible light spectrum [32, 33], where plasmonic nano-
lasers [34] and single-photon detectors [35] can serve as
transmitter and receiver, respectively. As the EM waves in the
THz band, optical nano-communications inside the human
body are faced with challenges, but have the advantage of the
molecular absorption losses in water (i.e., the majority of
blood content) being minimal within the optical window. In
blood vessels, the optical EM waves propagate through lossy
homogeneous blood plasma and interact with different cells,
particularly with the red blood cells (erythrocytes), being the
most abundant ones [36]. Propagation is dominated by
refraction through the cells in between transmitter and
receiver, and by reflection from the surrounding ones [37],
resulting in the multipath effect. However, red blood cells are
reported to focusing the light propagating through them [37,
38], thus reducing the exponential path loss in favor of
communications. The observed dependence of the focusing
properties on the shape and orientation of cells can be
potentially used to detect diseases and the presence of
pathogens, by identifying the changes in channel impulse
responses [37].
Finally, the fourth approach considers ultrasound waves as
information carriers [39], where their more favorable
propagation in body tissues with high water content shows a
potential for enabling communications over distances from
several µm to a few cm. Considering the small size of micro-
scale nodes, imposing limitations on the employment of
standard ultrasound transducers based on the piezoelectric
effect and mechanical vibrations, the photoacoustic effect
presents itself as a viable option for the excitation of
ultrasounds by nano-network devices [40]. The acoustic
waves are generated by the thermoelastic mechanism, where
light incident on a material surface is absorbed, the rapid
heating causing a rapid expansion which in turn generates
ultrasonic waves within the material. Therefore, the available
nano-lasers can be employed for optoacoustic transmission,
while optical resonators can be used for detection at the
receiver side [41].
To ensure power supply to both electromagnetic and
ultrasound devices, nano-wires made of zinc oxide are
proposed for energy harvesting, as they are able to generate
electric voltage when bent, e.g., due to a fluid flow in their
vicinity. For illustration, about a few thousands of such nano-
wires are needed to supply a single nano-machine, each wire
being 2 µm long and having 100 nm of diameter [42]. Another
proposed approach is powering these machines with remotely
generated ultrasounds, which can be converted by them into
electrical energy by using piezoelectric nano-elements [43].
While EM nano-communications receive a lot of attention
these days, one should note that the required dimensions of the
energy sources make this approach suitable for a micro-scale
rather than for a nano- one. These systems can be quite easily
integrated in networks at the macro-scale, as they share the
same communication medium. Consequently, they can act as
gateways between macro- and nano-devices. Both EM-based
and molecular nano-communication mechanisms are
addressed in the IEEE P 1906.1 standard, which has been
released in 2015 [44]. The standard defines nano-scale
communications, provides a model for ad-hoc nano-
communications, and suitable terminology focusing on the
nano-communication channel and some higher-layer
components, like packets, addressing, routing, localization,
and reliability.
As this short survey shows, there is a great variety of
available nano- and micro-communication methods, differing
in scale, applicable range, and associated delay. While FRET
can provide communications between nano-devices in a really
short (nano) time scale, its range is limited to about a dozen of
nanometers. On the other hand, graphene-based devices
working in the THz band are compatible with classical
wireless communications, but struggle to operate below the
micrometer scale. In between the two, a large number of
molecular mechanisms can be exploited. However, these
mechanisms are quite distinct from each other, as they use
different information carriers, thereby being incompatible
with each other, and with FRET and EM-based
communication mechanisms. Therefore, the design of
appropriate interfaces between nano-, micro- and macro-
networks is a critical challenge, and will be a turning point in
the further development of nano-communications.
IV. BODY AREA NETWORKS
Being on the larger and better explored side of the scale,
BANs have received considerably more attention over the
years than their nano-scale counterpart. Being capable of

VOLUME XX, 2020 6
monitoring their hosts and the surrounding environment,
BANs have found their application in a vast range of fields
[45], including healthcare, military, sports, and entertainment,
among others.
These networks accommodate different types of
communications, where the commonly distinguished
scenarios include, Fig. 3: among devices inside the human
body (in-body), in between devices inside the body and
wearable devices on the body (into-body), among wearable
devices (on-body), between wearable devices and external
access points (off-body), and among wearable devices in
different BANs (body-to-body).BANs can use different
communication technologies, including wired ones, smart
textiles, inductive coupling (ICC), body coupling (BCC), and
radio. While some of these technologies are universal and used
for all types of BANs, others are limited to certain scenarios
or just more convenient, and their employment greatly
depends on the application.
While wired communications have certain advantages
concerning security and reliability aspects, wires limit user's
movement and are prone to material failure, due to constant
twisting when the user is dynamic. Therefore, these systems
are suitable only for applications with users wearing special
suits and involved in low-dynamic activities, e.g., military
pilots and Formula 1 drivers [46]. The common drawbacks
associated with wires can be overcame by using smart textiles
[47], [48], which allow for the integration of power sources,
communications, and sensing circuitry within washable
clothes [49].
The transmission channel in ICC [50] is established
between two magnetic-coupled coils. Since the voltage
induced in the receiving coil is inversely proportional to the
cube of distance, the coupling exists only for very short
distances, i.e., in the order of centimeters. The established
channel quality highly depends on the coils' alignment, while
being independent of the surrounding tissue. Therefore, ICC
is suitable for into-body communications between external
devices and near-surface implants, or between nearby
implants. An additional advantage of ICC stems from the
possibility to use inductive power transfer, where the same
coils can provide both the communication link and the power
supply for the coupled pair. Since the two impose conflicting
requirements on the coil design, the system designer has either
to optimize the trade-off in a single-coil design or to use two
separately optimized coils [51].
In BCC, the transmitter and receiver couple with the user's
body and use it as a transmission medium [52], where one can
distinguish between capacitive and galvanic BCC. In the
former, the transmitter and receiver couple to the body through
capacitive links, created by the electrodes in contact with the
skin, while the additional floating electrodes at each side
couple with the environment, to provide a return path and
close the communication circuit [53]. On the other hand,
galvanic BCC exploits ionic properties of the body fluids for
signal transmission, with both transmitter/receiver electrodes
being in contact with the body [54], [55]. Unlike capacitive
BCC, which is limited to on-body communications, galvanic
BCC can be used for in- and into-body communications as
well. One should note that the field induced by either
capacitive or galvanic body coupled transmitters at
frequencies above 50 MHz is not quasi-static, and guided
wave propagation occurs [56]. The devices are in this case
designed to excite strong surface waves traveling along the
body [57].
Ultrasonic communications use sound waves at frequencies
above 20 kHz to transmit information, and their employment
in BANs has been proposed only recently [58]. The
ultrasounds exhibit a much lower attenuation in body tissues
than their EM counterparts [59], making them a more
favorable information carrier for in- and into-body
communications. Another attractive aspect of this mode of
communication is safety, since ultrasounds have been used for
medical imaging for a long time, without reported side effects
on the human body [58]. Moreover, ultrasound technology has
matured, with transceivers being commercially available. One
should note that for ultrasound communications, the devices
must be in contact with the body, due to poor propagation of
ultrasounds trough gasses, therefore, this type of
communication is mainly suitable for in- and into-body
communications. As in the case of BCC communications, on
the one hand, this can be seen as a limitation as contactless off-
body communication cannot be accommodated, but on the
other hand, it is an advantage in terms of privacy and co-
existence, as information is confined to the user’s body.
While ultrasound communications provide data rates only
up to 100 kbit/s, the employment of higher order modulation
schemes, such as 64 QAM [60], or spatial-multiplexing
MIMO [61], has been proposed to achieve data rates higher
than 10 Mbit/s. However, the transceiver structure complexity
and energy consumption associated with these schemes could
be beyond the reach for implanted devices, due to their small-
size and constrained energy source.
In addition to sound, light can be also used as an
information carrier in BANs. Besides ton-body
communications [62], optical wireless transmission can be
also employed to establish links between implants and on-
FIGURE 3. Communication scenarios in BANs.

VOLUME XX, 2020 7
body nodes [63], where data rates of up to 50 Mbit/s have been
demonstrated through 4 mm thick tissues [64]. However,
transdermal optical communications can be established with
devices implanted several centimeters into the body tissue
[65], by using wavelengths within the spectral window
between 700 and 950 nm, characterized by low absorption
[66]. With the power constraints of implanted devices being a
critical point, the extension of the longevity of implants can be
achieved by exploring retroreflective transdermal
communication for the transmission of data from an implant
to an outside device [66]. In this case, the light source is
provided by a less constrained on-body device and the implant
modulates the reflected light by a micro-electrical mechanical
system (MEMS) device, i.e., a miniature modulating
retroreflector (MMR). In addition to this unique feature of
transdermal optical communications, the immunity to EM
interference and inherent security due to limited propagation
range are some of the advantages of this technology.
Although the aforementioned communication systems are
associated with certain advantages, radio is by far the most
considered option for BANs, due to the convenience of
wireless transmission and the availability of a number of
mature technologies, namely, Bluetooth [67], Bluetooth Low
Energy (LE) [68], ZigBee [69], and ultra-wideband (UWB)
[70]. These technologies are also adopted by the physical layer
specifications in the existing standard for BANs, i.e., IEEE
802.15.6 [71]. Table 2 gives a summary of the communication
technologies, indicating the associated frequency bands,
ranges, and throughputs. Bluetooth was initially designed for
the exchange of audio and data between personal devices, but
its range and available data rates make it suitable for off-body
transmission of aggregated BAN data. Bluetooth LE was later
developed as its energy efficient, low latency, and low-cost
alternative, being compatible with Bluetooth devices and
suitable for communications with sensor devices. ZigBee
offers another low-energy and low-cost solution for BAN
communications, at the expense of a lower available data rate.
By allowing for multi-hop transmission to circumvent
propagation path obstructions, ZigBee can extend nodes’
coverage and improve the communication reliability.
However, UWB is probably the most popular radio
technology for BANs, due to its advantages associated with
the large bandwidth and low power density (below
-41.3 dBm/MHz). The latter makes UWB suitable for
operation in environments sensitive to electromagnetic
radiation, and in the close vicinity of the human body, as it
yields low exposure levels. Moreover, the large corresponding
penetration depths make UWB a popular choice for in- and
into-body communications.
One should also note that millimeter-waves BAN
communications have been considered recently, due to the
high capacity and low inter-BAN interference [72]. The
propagation characteristics of millimeter waves are both
attractive and challenging for BANs. On the one hand, the
high propagation losses are favorable for BAN coexistence,
secrecy and security reasons, as signals remain confined
within the area of the user’s close proximity. On the other
hand, these losses pose a great challenge on preserving the
information-bearing signal above the level required for
satisfying communication quality. Millimeter waves BANs
are still a niche research area, but the enabling technologies,
such as 60 GHz WLAN (WiGig) [73], already exist.
While BANs show a great potential, these systems are faced
with a number of challenges, including energy efficiency,
reliability, user safety, data security, simple use and comfort.
These matters have to be addressed at all design levels, i.e.,
from physical transmission, medium access, and routing
protocols, to top-level software design. Some of the most
important challenges are associated with the communication
channel, and the peculiarities of body-centric radio
propagation, where body-shadowing and users’ motion have a
significant influence on channel quality [74], [75]. Moreover,
the human body strongly affects the radiation characteristics
of antennas operating in its close vicinity, which imposes great
challenges on antenna design, especially in the case of in- and
into-body communications, where antennas are immersed in
highly dispersive human tissues [76], [77].
Despite the challenges, BANs have already demonstrated
great potential for personal systems. The ability to seamlessly
monitor the host and communicate with the surroundings has
already made BANs a part of medical treatments in modern
hospitals, and a helping hand in state-of-the-art training for
athletes. However, their true potential extends far beyond the
current systems, and could be achieved through a
collaboration between nano-networks and BANs, allowing for
information to be carried from a tissue inside the human body
to the outside world. In such a scenario, a nano-network will
transfer information to an implant, where a BAN would carry
it to an off-body access point, from where a large-scale
network would be in charge of delivering it to a remote
location. The implications are truly mind-boggling, when one
considers applications in healthcare or bio-metrics, as well as
those that are beyond one’s imagination today. The key
TABLE 2. Summary of main communication technologies for BANs.
Physical
link
System/Mechanism
Freq.
[GHz]
Range
[m]
Data rate
[Mb
it
/s]
Wired
Smart
-
textile
-
-
0.25
Wireless
Optical comm.
10
5
0.05
50
ICC
< 0.02
0.2
2.5
Ultrasound
< 0.3
0.5
0.1
Capacitive BCC
< 0.2
1
10
Galvanic BCC
< 0.05
1
0.064
Bluetooth LE
2.5
10
1
WiGig
60
10
7 000
UWB
3
-
10
50
480
Bluetooth
2.5
100
3
WiFi
2.5, 5.8
100
100
ZigBee
2.5
200
0.25

VOLUME XX, 2020 8
enablers of such truly personal communications are the
interfaces between devices and mechanisms at different
scales. An overview of some mechanisms that can be
exploited for this purpose is given in the next section.
V. NANO-MICRO-MACRO INTERFACES
While numerous communication mechanisms in both nano-
and micro-scales have been proposed and thoroughly
investigated, they are still quite disconnected from each other.
It is mainly because they use different information carriers,
e.g., FRET/photons, THz waves, diffusing molecules, and
DNA strands. Consequently, it is challenging to transfer data
from one nano-network type to another, or from nano- and
micro-scales to the macro-world of conventional wireless
devices. Still, some interfaces can be established by exploiting
the physical properties of specific molecules or materials,
which are presented in the following subsections and
summarized in Table 3. In Fig. 4, a visual understanding of
mechanisms mentioned in subsections A-D is also given,
while in Fig. 5 two cases of micro-macro EM communications
are illustrated, as discussed in subsection E.
A.
LIGHT-STIMULATED CHANNELRHODOPSINS
Channelrhodopsins are small protein molecules, with a size
of about 5 nm, naturally occurring in some green algae
organisms, able to open light-induced channels for ions.
Recently, they became highly investigated [78], [79], inspiring
quite a new discipline called optogenetics, which is about
controlling living tissues with light. Channelrhodopsins, when
treated with light, have an ability of opening a pore (channel)
where positive ions, e.g., present in blood, can flow through.
Such a channel remains open by at least 10 ms, which is
enough for the flowing ions to change the electrical potential
at the other side of the ion channel. Furthermore,
channelrhodopsins can be activated by FRET as well [80].
From the nano-communications viewpoint,
channelrhodopsins can be then understood as light-to-voltage
converters. As the voltage can be later measured by an EM-
based micro-device or a BAN, channelrhodopsins constitute
an interface between these networks, being able to transfer
FRET signals to electrical ones. The full cycle of a
channelrhodopsin, from closed to open and then closed and
able to accept stimuli, is as long as 5 s [81], thus, the
throughput of data transferred via a single channelrhodopsin
remains far below 1 bit/s. A solution can be a large layer of
channelrhodopsin molecules working in parallel [80], which
has been shown to have a throughput of about 50 bit/s,
achieved with a bit error ratio kept below 10-3.
Channelrhodopsins can be also embedded into neurons,
replacing receptors at the neuron membrane, which has
already been proved experimentally [82], [83]. Like neuron
receptors are able to receive stimuli from tens of thousands of
other neurons via neurotransmitters, similarly
channelrhodopsins signals can be received from many
sources. Such a neuron is then stimulated by light or FRET. It
has been shown that channelrhodopsin-controlled neurons are
able to produce up to 200 impulses per second [84], which
means about 200 bit/s for the respective channel throughput.
B.
LUMINESCENCE BY BRET
BRET stands for bioluminescence resonance energy
transfer and is a process similar to FRET, as explained in
Section III, although the donor energy does not come from
external excitation, but from a chemical reaction. In this
reaction, a luciferase molecule, like Vluc, Rluc, Fluc or
NanoLuc, is oxidized in the presence of a specific substrate
molecule, a luciferin. The reaction produces energy that is
emitted as a photon or can be caught by a donor molecule, if
situated nearby. From the communication viewpoint, BRET
can initiate a single or multi-hop FRET transmission without
any external source of donor excitation. As the mentioned
reaction is strictly dependent on the suitable amount of
luciferin substrates, it can be controlled by molecular
diffusion, for example. Thus, BRET has two crucial
advantages: (a) local origin via chemical reaction, and (b)
control with a molecular communication mechanism, i.e.,
diffusion. Consequently, BRET can intermediate between
molecular communication mechanisms and FRET
transmissions.
BRET has its limitations related to the physical properties
of luciferases and to the chemical reaction characteristics.
First, the reaction turnover rate is quite low: for NanoLuc
luciferases it is 0.5 s, while for RLuc it is even 5 s [85]. For
comparison, a FRET donor molecule is ready for energy
TABLE 3. Potentials and limitations of interfacing mechanisms
Interfacing mechanism
Source
Destination
Potentials
Challenges
Channelrhodopsins FRET networks Neurons / EM micro-
devices / BANs Light-to-voltage converters
Limited throughput, below 1
bit/s for a single ChR, 200 bit/s
in neuron
Photodetectors FRET networks BANs Very high potential throughput
of Mbit/s
Low photodetection efficiency
< 50%
BRET
Molecular comm.
FRET networks
Local energy source
Throughput of few bits/s
ATP
Molecular comm.
FRET networks / neurons
Extremely ubiquitous molecules
Difficult to be controlled
EM communication EM micro-devices BANs Two-way communication
Millimeter ranges
THz or higher frequencies
required
SPR sensors BANs EM micro-devices High throughput Specific incidence angle of the
hitting EM wave required
BAN-controlled light
diodes
BANs FRET networks Very high potential throughput
of Mbit/s
Line-of-Sight conditions
required

VOLUME XX, 2020 9
absorption just after a previous emission, which usually occurs
in a few nanoseconds. In effect, a single luciferase can pass
only around 1 bit/s, comparing with over 10 Mbit/s for a
typical FRET transfer. Second, similarly to FRET,
communication distances for BRET are below 10 nm [80].
C.
THE ROLE OF ATP
ATP (adenosine triphosphate) is the most common energy
currency for living cells. It is extremely ubiquitous: despite
that a single ATP is about 1 nm in size, each human body
produces more of these molecules during the day than the
whole-body weight. An ATP molecule consists of an
adenosine and three highly energetic phosphate groups. Living
organisms usually spend ATP energy via its hydrolysis,
removing one phosphate group and thus creating an ADP
(adenosine diphosphate) molecule; in this process 30.6 kJ is
released per mole of ATP.
While being so common energy carriers, ATP molecules
are also proved to be information carriers between living cells.
ATP can act similarly like neurotransmitters, which, in
biology, is called purinergic signaling [86], [87]. Specific
receptors on neural cells are already known, namely P2X and
P2Y, matching strictly ATP molecules. The former opens an
ion channel on a cell membrane, like a typical neuron receptor,
while the latter triggers releasing calcium stores inside the cell.
Thus, ATP molecules can carry information from a cell to cell
via diffusion, like neurotransmitters.
ATP can initiate communication not only to nerve cells, but
also to BRET/FRET networks. ATP is required for chemical
reactions starting BRET with, e.g., Fluc (firefly luciferase)
molecules, so it can be used to control these reactions [88].
Also, ATP is the energy source for the movement of kinesins
and dyneins. These molecular motors advance 8 nm for each
ATP molecule spent [89], [90], so this way of transporting
information can be clearly controlled via careful ATP
delivery.
As ATP is so important for nano-communications, its
production should be controlled, which, fortunately, is
feasible. ATP can be released by neural cells, like
neurotransmitters, but, as previously mentioned, ATP is also
produced from ADP by all living organisms. In plants and
some bacteria, it is done during the light part of the
photosynthesis, with a reaction called photophosphorylation,
using the energy of light. In non-photosynthetic organisms,
e.g., humans and animals, ATP is produced in catabolic
processes of so-called cellular respiration via oxidation of
carbon-containing structures, like fatty acids or carbohydrates,
e.g., from a single glucose C6H12O6 molecule, living cells
produce up to 38 ATP molecules [91].
Summing up, ATP molecules can intermediate between
different types of communications. ATP molecules can be
provided directly, or their production can be stimulated with
light (light-induced) in photosynthetic structures or by
delivering carbon-containing compounds to non-
photosynthetic cells. ATP initiates BRET communications,
gives fuel for movement of molecular motors or fires actions
of cells having P2X/P2Y receptors, neuronal actions in
particular.
D.
PHOTODETECTORS AND SPR
Recently, an innovative system has been presented, where
genetically modified Escherichia coli bacteria integrated with
a wireless endoscopy capsule acquired information regarding
internal bleeding inside gastrointestinal tract [92]. The bacteria
signaled the information via luminescence to the
photodetectors designed for this purpose [93]. The system has
been successfully tested with in vivo experiments and is an
example of an efficient communication interface, via light,
between a molecular system and macro-scale devices.
The bacteria mentioned above send a very simple
information, just a confirmation that a bleeding is located,
without any bit transmission. Photodetectors technology has
progressed very rapidly in the last twenty years, and currently
these devices, commercially available, are able to
intercept/collect much more subtle signals; in particular, the so
called single-photon detectors (SPDs) look very promising, as
they are able to count and time-stamp incoming photons.
These devices are therefore able to receive bit transmissions
from FRET-based nano-networks, as FRET-receivers emit
received signals as photons.
Among many families of SPDs, not all of them are suitable
for creating networking interfaces. Real photodetectors are
characterized by intrinsic limitations, resulting from the
specific physical mechanism of photodetection. Popular
solutions, such as superconducting nano-wire SPDs or
transition-edge sensors, are working in cryogenic
temperatures only, in order to reduce background noise. On
the other hand, much more suitable are single-photon
avalanche diodes (SPADs), able to perform at room
temperatures. SPAD photodetectors are commonly used to
measure FRET efficiency in biophotonic applications [94].
The size of the active area of a SPAD is usually a few dozens
of micrometers, but if larger dimensions are required, then
SPAD arrays are commonly created. In a SPAD, an absorbed
photon creates an electron-hole pair that is, in turn, multiplied
in the avalanche process. This process must be further stopped
in order to make the SPAD sensitive for the next photons,
which usually takes 10 to 100 ns [94], which means that
photons can be accepted with a rate of the order of 10 Mbit/s.
While the evolution of SPAD technology is progressing well,
the main challenge is their photodetection efficiency, which
rarely exceeds 50% and is not stable in the whole visible and
infrared spectrum [94]. In consequence, probably, at least a
few absorbed photons are required per each bit of data
(repetition coding), which slows down the communication
throughput of this technology. Recently, a single-photon
detector based on cadmium sulfide nano-wire, but operating
in room temperatures, has been also presented [95] and can be
treated as an alternative for SPADs. Summing up, single-
photon detectors, especially SPADs, are a developing
technology that can be seriously considered as a solution for
interfacing FRET-based and larger-scale networks.

VOLUME XX, 2020 10
When discussing optical interfacing solutions, Surface
Plasmon Resonance (SPR) should be also mentioned. The
SPR phenomenon occurs when an optical/infrared/THz wave
hits a metallic or graphene surface. If specific conditions
regarding the incidence angle and the wave frequency are met,
a rapid oscillation of electron density is created, which
propagates along the surface of the metal/graphene. This
oscillation is called a plasmon and it can travel about 10 µm
[28] in graphene or up to 60 µm in silver/gold [96]. Classical
prism-based SPR sensors are quite large, but solutions based
on optical fibers are much more compact with sizes of about
20 µm [97]. As the conditions for plasmon creation depend
also on the environment’s parameters, SPR sensors are
commonly used to study biological structures. Yet, the SPR
phenomenon can be considered as a method for converting
optical or infrared signals into plasmons that in turn can be
detected by micro-scale graphene devices. SPR sensors can
achieve very good response times of about 1 µs [98], thus the
throughput of such an interface might be in the order of
1 Mbit/s. However, a limiting factor is the specific incidence
angle of the wave hitting the graphene surface: it requires a
precise geometric configuration of the whole interface system,
which probably limits its application to the case of a macro-
BAN node transmitting to a static graphene micro-device.
E.
MICRO-MACRO EM COMMUNICATIONS
Communications between micro-scale nodes and an
external BAN can be also established by employing EM
waves at THz or optical bands as information carriers. The
extremely high path loss in the presence of multiple tissues in
between transmitter and receiver make a direct
communication between a nano-node in the blood stream and
an external BAN device particularly challenging [99].
However, communication with external BAN devices could
be achieved by introducing mediator devices, assisting the
information delivery from micro-scale devices circulating
through the blood stream to an on-body macro-scale device
placed on the skin.
These devices could be micro-scale nodes implanted in
between blood vessels and the skin, employing THz, optical
or ultrasound waves to communicate with both sides [100],
[101]. Both the micro-scale devices carrying information and
the implanted one can be powered by energy delivered by
ultrasound waves emitted by the on-body BAN node [101].
The information exchange can then take place while the
circulating nano-node is within the portion of the blood vessel
in which it can harvest the ultrasound waves’ energy.
However, the location of these mediating devices must be
chosen carefully, so that favorable propagation conditions and
a high chance of establishing contact with nano-nodes
circulating through the body are ensured. The former
requirement means that the body parts with thin tissue layers
between blood vessels and the skin are preferable, while the
latter suggests that a micro-scale gateway should be placed
next to veins and arteries that see most of the blood volume
passing through within a short period of time. Moreover,
except possibly for critical applications with users in hospital
beds, the mediator node location is also constrained by
aesthetics and the practicality of on-body device placement,
considering daily life activities.
For example, the internal jugular veins in the neck provide
a high level of interaction with nano-nodes circulating through
the body, as they host 14% of the total blood-flow in the body
[102], but the attachment of an external node on the neck is
inconvenient for regular daily activities. On the other hand, the
veins in the wrist are attractive for their proximity to the
surface, i.e., thin tissue and superior accessibility, since the
external collector device could be integrated within a watch or
a bracelet, but only 1% of the total blood flows towards the
heart through these veins [103].
Alternatively, the mediating devices could be in-body BAN
nodes that can use light, THz waves or ultrasound to
communicate with micro-scale devices, and microwaves with
devices on the body surface, or even with nearby off-body
devices. Since these devices are larger and more capable than
their micro-scale counterparts, their position is less
constrained by the distance from the on-body node and can be
better optimized in terms of proximity to blood vessels with a
high probability of interaction with circulating nano-nodes.
Propagation through body tissues at microwaves is much less
restricted than in the THz band, but the high dispersion losses
due to conductivity still limit communication to distances of
the order of 1 cm of body tissue [104]. However, at
microwaves, communications can be used to deliver
information from implants directly to a device in the user’s
proximity, such as a medical instrument next to the hospital
bed [105], [106]. UWB communications seem to be the most
attractive option for into-body communications, due to the
high tissue penetration depths [76], [77], but other
technologies discussed in Section IV could be employed.
Instead of microwaves, ultrasonic communications can be
also used for into-body communications with BAN implants
in this scenario [58], or even directly with micro-scale devices.
Ultrasounds are characterized by lower absorption losses, and
their proved safety through the long usage in medical imaging
is another attractive property [59]. Similarly, transdermal
optical communications can be used to establish links with in-
body BAN or micro-scale devices, however, with more strict
limitations than with ultrasound carriers. The direct optical
link between micro-scale and on-body devices is particularly
challenging, and unlikely to be established with optical EM
communications in the outward direction.
F.
SUMMARY AND RESEARCH CHALLENGES
Summing up the solutions discussed above, one can say that
two trends are dominating. First, traditionally in
communications, wireless solutions are extensively popular,
as the wireless medium is now ubiquitous, having in mind all
tiny sensors and IoT devices. The second group of solutions is
based on light, which, on the one hand, is still an EM wave,
but, on the other hand, an energy carrier commonly used in
biological systems. Except for the cases already described, i.e.,

VOLUME XX, 2020 11
channelrhodopsins, luminescence and photodetectors, optical
signals, e.g., emitted by BAN-controlled diodes, can easily
intermediate between macro- and nano-networks. Due to the
scale difference, the signals coming from macro-devices are
of a broadcast nature for nano-networks, but can be filtered by
properly designed nano-devices. For example, one can
consider using an optical source, such as a laser, to transfer
signals into FRET-based nano-networks, where the nano-
transceivers can be fluorophores, such as Alexa, DyLight or
Atto selective dyes, i.e., commercially available bio-
engineered molecules. There is a wide variety of these dyes,
characterized by different absorption spectra in the visible
light range. from close to ultraviolet (380 to 400 nm), up to
nearly infrared (700 to 750 nm).
They can be used for the frequency-selective reception of
optical signals, similarly as in standard wavelength division
multiplexing (WDM) receivers. Optical signals can be also
received by molecular communication systems, where the
properties of bacteria, such as Escherichia coli, can export
protons (H+) and change the pH value of its environment in
response to optical stimulation [107].
The approaches presented in the above subsections prove
that despite nano-, micro- and macro-communication
mechanisms are quite distinct from each other, some lessons
from physics, optogenetics, biotechnology, and wireless
communications can be learned and then interfacing
techniques are at one’s fingertips. However, one should be
aware of the low level of their maturity: the physical
solutions and biological components are ready, but still, there
is much engineering work to be done to have the whole inter-
scale communications systems operational. Except for the
research challenges specific for the chosen interfacing
techniques, there are at least three general challenges
pivotally important for the whole subject:
a) Interdisciplinary cooperation - Understanding the
mechanisms and phenomena that are the basis for inter-
scale communications requires knowledge from many
scientific areas. While information and communication
technologies are in the center of this research, physics,
biotechnology, medicine, and optogenetics are crucial
for making progress on interfacing solutions.
Cooperation among these disciplines is strenuous, as
different research communities describe phenomena
with a distinct language and are used to focus their work
on different goals. However, such a cooperation, much
needed, will result in a substantial progress and a holistic
expertise on this whole subject.
b) Experimental effort - Most of the current research in
nano-communications is performed via a theoretical
approach or computer simulations, sometimes not using
realistic assumptions. This subject requires more
experimental work in many areas, e.g., biological
samples or physical nano-devices. While in BANs there
are relatively more experimental studies, they do not
concern interfaces with nano- and micro-scale networks.
c) Control over device positions and mobility - Many of
the discussed interfacing techniques require a precise
control over the relative positions of the communicating
nodes, e.g., FRET networks must be exactly positioned
so that their signals are received by channelrhodopsins
or ATP molecules should be carefully delivered to
initiate BRET. Such bio- or nano-engineering control
over molecules and nodes in their environment is one of
the most important barriers on the way to the
development of interfacing solutions.
In general, communications systems and networks are
described by a number of parameters and entities, which
depend on the nature of the communication and sometimes
(a)
(b)
FIGURE 5. Micro-macro EM communications with BAN and nano
device mediator nodes. (a) BAN implant as a mediator node. (b) Nano-
device as a mediator node.
FIGURE 4. Communication interfaces for FRET and molecular
networks (the device scale is not preserved).

VOLUME XX, 2020 12
even on the specific application. The description of
transmitters and receivers, and the characterization of the
channel in between them are basic requirements for any
system, while architectures, routing algorithms and protocols
form some of the bases for networks, and this paper provides
some information in this direction. While interfaces have
been addressed, as well as basic transmission and reception,
together with some coverage ranges and data rate capacity,
other matters are still open for research, such as models for
channels, interference, connections capacity, routing,
addressing, reliability, and efficiency, among many others.
VI. CONCLUSIONS
Nano-communications between groups of molecules, cells,
or EM-based micro-devices, are one of the hottest research
areas in communications in recent years. The progress in this
discipline is strenuous, since it requires cooperation between
IT and medical experts, but the potential applications are
countless, extending from healthcare, such as remote
diagnostics, surgery and localized drug delivery, to sports,
entertainment and military, while encompassing Human-
Internet integration. The latter is a vision of truly personal
communications, where the far edges of the communication
network are deeply inside people’s bodies, allowing for
delivering the signals directly from human nerve cells to the
outside network.
This paper presents a brief survey of important nano-
communication mechanisms, including molecular
mechanisms, Förster resonance energy transfer phenomenon
and EM micro-devices. It also provides an overview of the
BAN communication technologies, including smart-textiles,
inductive- and body-coupling mechanisms, and a number of
available suitable radio technologies (e.g., UWB, Bluetooth,
ZigBee, and WiFi). However, the main contribution of this
paper is in the summary of potential interfacing mechanisms
between nano-networks and BANs, which will serve as
mediators to the outside world. These interfaces are the critical
aspect of the envisioned truly personal communication
systems and require dedicated research efforts to fully realize
their potentials.
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VOLUME XX, 2020 15
PAWEL KULAKOWSKI received his Ph.D. in
telecommunications from the AGH University of
Science and Technology in Krakow, Poland, in
2007, and currently he is working there as an
assistant professor. He spent about 2 years in total
as a post-doc or a visiting professor at Technical
University of Cartagena, University of Girona,
University of Castilla-La Mancha and University
of Seville. He was involved in research projects,
especially European COST Actions: COST2100,
IC1004 and CA15104 IRACON, focusing on
topics of wireless sensor networks, indoor localization and wireless
communications in general. His current research interests include molecular
communications and nano-networks. He was recognized with several
scientific distinctions, including 3 awards for his conference papers and a
governmental scholarship for young outstanding researchers.
KENAN TURBIC (S’14–M’19) has received his
MSc degree from the University of Sarajevo in
2011, and a PhD degree (Hons.) in Electrical and
Computer Engineering from IST, University of
Lisbon, in 2019. He is currently a postdoctoral
researcher at the INESC-ID research institute,
Lisbon, Portugal. His main research interests are
wireless channel modelling, with a particular
interest in Body Area Networks. He is actively
participating in the COST Action CA15104
(IRACON), to which he has contributed with
several technical documents and is serving as one of the Section editors for
the final report book.
LUIS M. CORREIA (S’85-M’91–SM’03) was
born in Portugal, in 1958. He received the Ph.D.
in Electrical and Computer Engineering from IST
(University of Lisbon) in 1991, where he is
currently a Professor in Telecommunications, with
his work focused on Wireless & Mobile
Communications in the areas of propagation,
channel characterisation, radio networks, traffic,
and applications, with the research activities
developed in the INESC-ID institute. He has acted
as a consultant for the Portuguese
telecommunications operators and regulator, besides other public and
private entities, and has been in the Board of Directors of a
telecommunications company. Besides being responsible for research
projects at the national level, he has participated in 32 projects within
European frameworks, having coordinated 6 and taken leadership
responsibilities at various levels in many others. He has supervised more
than 200 M.Sc./Ph.D. students, having edited 6 books, contribute to
European strategic documents, and authored more than 500 papers in
international and national journals and conferences, for which served also
as a reviewer, editor and board member. Internationally, he was part of 36
Ph.D. juries, and 66 research projects and institutions evaluation committees
for funding agencies in 12 countries, and the European COST and
Commission. He has been the Chairman of Conference, of the Technical
Programme Committee and of the Steering Committee of various major
conferences, besides other several duties. He was a National Delegate to
the COST Domain Committee on ICT. He was active in the European
Net!Works platform, by being an elected member of its Expert Advisory
Group and of its Steering Board, and the Chairman of its Working Group on
Applications, and was also elected to the European 5G PPP Association. He
has launched and served as Chairman of the IEEE Communications Society
Portugal Chapter.