Revolutionizing Wireless Communication: The Convergence of

CNT and Antennas for Futuristic THz Communication

Atanu Chowdhury

and Soumya Sen

Calcutta Institute of Technology, Uluberia, West Bengal, India

University of Engineering & Management, Jaipur, Rajasthan, India

Keywords: THz Communication, Nano-Antenna, CNT, High Gain.

Abstract: This manuscript presents a circular patch Carbon Nano Tube (CNT) antenna having two “Z” slots and a

defected ground structure (DGS) suitable for optical frequency applications. A semi-spherical layer of the

Polyflon Cuflon layer(ε

=3.41) is attached to the ground to enhance the gain resulting in an improvement in

radiation efficiency. The proposed antenna dimension is 40 nm × 40 nm × 1.6 nm based upon a silicon substrate

(ε

=11). The proposed antenna covers a bandwidth of 2 THz to 6.5 THz. Without the attached layer, the

maximum gain is 3.5 dB while the attachment of the layer increases it up to 6.1 dB. The Radiation efficiency

is also improved from 62% to 81% by implementing the attachment. The overall structure is designed and

simulated in HFSS 21.0 software.

INTRODUCTION

Microwave researchers are currently focusing on

modern communication technologies and modulation

techniques to address bandwidth challenges, aiming

to enhance spectral utilization efficiency (PAULRAJ

et al., 2004). These efforts also target improvements

in data rates and frequency reuse. However, Shan-

non’s theory imposes an upper limit on channel ca-

pacity, even with advancements like MIMO

technology. To overcome this limitation, researchers

are considering higher bands applicable for optical

frequency range communication, such as the band of

1000 MHz to 10 THz (Akyildiz et al., 2014).

Recently, a “bow- tie” antenna has been optimized

for communicating in between 110-292 THz,

utilizing a glass as the base and an aluminium dipole

antenna to optimize parameters (Kavitha et al.,

2023).

Despite its potential, THz signal usage lags

behind that of the electrical or optoelectronic field

due to hardware limitations, particularly in THz

signal generators and sensors. However, since the

1980s, the accessibility of nanosecond lasers and

photo-conductive antennas has enabled several

fields, like medical science, pharmaceutical-

https://orcid.org/0000-0002-9323-4839

https://orcid.org/0000-0002-6354-5206

oriented research, and also pri- vacy, to utilize THz

waves (Apriono et al., 2015; Car-valho et al., 2023).

The advantages of THz communi- cation include

enhanced directionality, data security, and reduced

attenuation (Federici and Moeller, 2010).

Nevertheless, higher atmospheric absorption limits its

utility for short-distance communication. Despite

high demand over the last 2 decades, hardware imple-

mentation for THz frequency range operation remains

challenging.

In the realm of THz services, recent developments

in- volve the creation of various metal-fabricated

nano- antennas and array orientations, such as lens

antennas, horn antennas and many more (Malhotra et

al., 2017; Konstantinidis et al., 2015; Alazemi et al.,

2016; Yu et al., 2020; Hao et al., 2017). Fabricating

these high-frequency antennas poses challenges due

to measurements in the nanometer range. Con-

sequently, researchers are exploring alternative

materials like graphene and carbon nanotubes to

mitigate skin depth reduction associated with

traditional materials like gold and copper. Recent

studies have compared antenna materials and their

performances for THz communication nanoantenna

designs (Ghaf- far et al., 2019).

Moreover, simulations of an antenna optimized

by a silicon lens having a silicon substrate have

shown promise, with additional layers applied to the

lens surface to boost effectiveness (Dash et al.,

Chowdhury, A. and Sen, S.

Revolutionizing Wireless Communication: The Convergence of CNT and Antennas for Futuristic THz Communication.

DOI: 10.5220/0013231800004646

Paper published under CC license (CC BY-NC-ND 4.0)

In Proceedings of the 1st International Conference on Cognitive & Cloud Computing (IC3Com 2024), pages 25-29

ISBN: 978-989-758-739-9

2020). Researchers are also examining broadband

imple- mentations using the bow-tie antenna in

conjunction with capacitive lines and a hemispherical

silicon lens. However, further enhancements in

electromagnetic properties are needed to improve

radiation effective- ness (Wahyudi et al., 2017).

Research indicates that a silicon lens is useful for the

enhancement of the di- rectional capability of a light-

conducting antenna on a Galium Arsenite base within

the THz spectrum range (Jyothi et al., 2016).

Additionally, ”bow-tie” antennas on a surface made

of InP, combined with hemispheri- cal and bullet-type

silicon lenses, have been utilized to eliminate surface

waves, resulting in improved gain, efficiency, and a

wider spectrum (Li and Song, 2016). This research

article introduces a novel concept: A circular patch

antenna with two ”Z” slots and a de- fected ground

structure (DGS) has been developed for optical

frequency applications. To enhance its gain and

radiation efficiency, a semi-spherical layer of

Polyflon Cuflon material (with a relative permittivity

of 3.41) is attached to the ground. The antenna is

designed with dimensions of 40 nm × 40 nm × 1.6

nm on a silicon substrate with a relative permittivity

of 11. It operates within a bandwidth ranging from 2

THz to 6.5 THz.

Before attaching the layer, the antenna achieves a

maximum gain of 3.5 dB. However, with the attached

layer, the gain increases significantly to 6.1 dB. Addi-

tionally, the radiation efficiency improves from 62%

to 81% with the implementation of the attached layer.

The entire structure is designed and simulated using

HFSS 21.0 software.

ANTENNA DESIGN &

ANALYSIS

The proposed antenna is designed in a few steps on

the silicon substrate. The volume of the substrate is

40 nm × 40 nm × 1.6 nm. In step-1, a simple

circular horizontally aligned CNT patch antenna

is designed with a radius of 7 nm and a feedline

having a length of 17 nm, and a width of 2 nm. This

structure is shown in Fig. 1(a). In step-2, the ground

is defected to a rectangular shape as shown in

Fig.1(b). In step-3, the circular patch is slotted with

two “Z”-slots to enhance the coverage of the

frequency band as shown in Fig. 1(c). In step-4, a

layer of Polyflon Cuflon (ε

=3.41) is attached to the

ground as shown in Fig. 1(d). This is done to

increase the gain as well as efficiency. As we all

know the dielectric constant of the silicon substrate

(ε

) and air is 11 and 1 respectively. To counter this

gap between these dielectric layers, a matching layer

was needed. So, mathematically a layer is to be

introduced whose dielectric constant can be found

from the equation (1).

𝜀





𝜀



× 𝜀



(1)

This equation gives a value of around 3.4058.

This is why, a material is so chosen whose dielectric

constant is 3.41 i.e. Polyflon Cuflon.

Figure 1: Antenna designs in different steps: Top view and

Bottom view in (a) step-1, (b) step-2, (c) step-3, (d) step-4

(optimized).

RESULTS

3.1

S-Parameter

The S(1,1) parameter is studied to determine the

return loss. It is significant to obtain the bandwidth

of the antenna. In this study, the S(1,1) parameter is

discussed for all the design steps involved to get the

optimized value as given in Fig. 2. In the first step, it

is from 3.3 THz to 5.1 THz. In step-2, it is improved

from 2.6 THz to 5.6 THz. In the next one, it provides

a bandwidth of 2.4 THz to 6 THz. And finally, after

the implementation of the said layer, the obtained

bandwidth is from 2 THz to 6.5 THz.

3.2

Radiation Pattern

The S(1,1) parameter result has provided two

resonant frequencies in the obtained band.

These

are 3.4 THz and 4.6 THz. The radiation pattern of

these frequencies is shown in Fig. 3 and Fig. 4

respectively. It shows a pattern uniformly distributed

in each direction while the phase angles are 0

, 90

IC3Com 2024 - International Conference on Cognitive & Cloud Computing

Figure 2: Reflection Co-efficient.

Figure 3: Radiation Pattern at 3.4 THz.

Figure 4: Radiation Pattern at4.6 THz.

3.3

Gain & Efficiency

In this section, the gain, and efficiency are studied.

This section shows how the Polyflon Cuflon affects

the performance of the antenna. Fig.5 and Fig.6

show the gain and efficiency of the proposed

antenna respectively. These show that without the

attached layer, the maximum gain is 3.5 dB while the

attachment of the layer increases it up to 6.1 dB. The

Radiation efficiency is also improved from 62% to

81% by implementing the attachment.

Figure 5: Gain of the proposed nano-antenna.

Figure 6: Radiation Efficiency of the proposed nano-

antenna.

COMPARISON

The proposed work is compared with recent

literature in Table 1.

Revolutionizing Wireless Communication: The Convergence of CNT and Antennas for Futuristic THz Communication

Table 1: Table of Performance Evaluation.

References

Dimension

(

)

B/W

(THz)

Max.

Eff.

(%)

Alazemi, 2016 46×24×0.432 0.4

Yu, 2020 10×6.7×1.5 0.3 99.5

Dash, 2020

P 1 93.7

Wahyudi, 2017 6×6×0.3 0.3 90

Jyothi, 2016 1.2×1.2×0.625 2 75

Li, 2016

P 1 90

40×40×1.6 4.5 82

CONCLUSION

The design of the antenna is elaborated in steps in

this paper. The compact size of the antenna is one

of the significant parts of this work. The band-

width achieved is 4.5 THz (2 to 6.5 THz) with a

maximum efficiency is 82% and a maximum gain

is about 6.1 dB. This antenna covers the full band

of the optical frequency. The performance

improvement is also studied using a matching layer

(Polyflon Cuflon). It shows a new way to improve

the antenna performance.

Advancements in fabrication techniques

promise to revolutionise multiple technological

sectors through the development of nanoantennas.

These techniques will allow for precise control

over dimensions and materials, consequently

enhancing performance and efficiency. Nano

antennas hold potential across a spectrum of

applications including communication

technologies, sensing, imaging, and energy

harvesting. Breakthroughs in terahertz technology

and meta-material development are anticipated,

further amplifying their impact. Ongoing research

and innovation in this field are poised to unlock

transformative applications in electronics,

telecommunications, and beyond.

ACKNOWLEDGEMENTS

Both authors express their heartiest

acknowledgement to themselves, their

organizations and ultimately to the god for the

completion of the research work.

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Revolutionizing Wireless Communication: The Convergence of CNT and Antennas for Futuristic THz Communication