Thennarasan Sabapathy
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Preferred name
Thennarasan Sabapathy
Official Name
Thennarasan, Sabapathy
Alternative Name
Sabapathy, Thennarasan
Sabapathy, Thenna
Sabapathy, T.
Sapabathy, T.
Main Affiliation
Scopus Author ID
35424377200
Researcher ID
AAA-9706-2019

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Compact ultra-wideband monopole antenna loaded with metamaterial

2020-02-01 , Al-bawri S.S. , Goh H.H. , Islam M.S. , Wong H.Y. , Jamlos M.F. , Narbudowicz A. , Muzammil Jusoh , Thennarasan Sabapathy , Khan, Rizwan D. , Islam M.T.

A printed compact monopole antenna based on a single negative (SNG) metamaterial is proposed for ultra-wideband (UWB) applications. A low-profile, key-shaped structure forms the radiating monopole and is loaded with metamaterial unit cells with negative permittivity and more than 1.5 GHz bandwidth of near-zero refractive index (NZRI) property. The antenna offers a wide bandwidth from 3.08 to 14.1 GHz and an average gain of 4.54 dBi, with a peak gain of 6.12 dBi; this is in contrast to the poor performance when metamaterial is not used. Moreover, the maximum obtained radiation efficiency is 97%. A reasonable agreement between simulation and experiments is realized, demonstrating that the proposed antenna can operate over a wide bandwidth with symmetric split-ring resonator (SSRR) metamaterial structures and compact size of 14.5 × 22 mm2 (0.148 λ0 × 0.226 λ0) with respect to the lowest operating frequency.

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Decagonal c-shaped csrr textile-based metamaterial for microwave applications

2022-01-01 , Hossain K. , Thennarasan Sabapathy , Muzammil Jusoh , Soh Ping Jack , Al-Bawri S.S. , Osman M.N. , Hasliza A Rahim @ Samsuddin , Torrungrueng D. , Akkaraekthalin P.

This paper introduces a decagonal C-shaped complementary splitring resonator (CSRR) textile-based metamaterial (MTM). The overall size of the proposed sub-wavelength MTM unit cell is 0.28λ0 ×0.255λ0 at 3 GHz. Its stopband behaviour was first studied prior analysing the negative index properties of the proposed MTM. It is worth noting that in this work a unique way the experiments were completed. For both simulations andmeasurements, the proposed MTM exhibited negative-permittivity and negative-refractive index characteristics with an average bandwidth of more than 3 GHz (considering 1.7 to 8.2 GHz as the measurements were carried out within this range). In simulations, the MTM exhibited negative-permittivity properties within the range of 1.7 to 7.52 GHz and 7.96 to 8.2 GHz; and negative-refractive index from 1.7 to 2.23 GHz and 2.33 to 5.09 GHz and 5.63 to 7.45 GHz. When measured from 1.7 to 8.2 GHz, negative-permittivity and negative-refractive index characteristics are exhibited throughout an average bandwidth of more than 3 GHz. Similarly, the transmission coefficient attained in simulations and measurements indicated about 3 GHz of bandwidth, from 1.7 to 3.88 GHz and from 6.68 to 7.4 GHz. The satisfactory agreement between simulations and experiments indicates the potential of the proposed MTM for microwave applications.

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Design of Reconfigurable Antenna for RFID System

2021-07-26 , Renukka Sivakumar , Thennarasan Sabapathy , Muzammil Jusoh , Soh Ping Jack , Mohamed Nasrun Osman , Salem Al-Bawri S. , Jayaprakasam S. , Mohd Najib Mohd Yasin , Saluja N.

This paper proposes a reconfigurable antenna for RFID system which can operate between 860MHz to 960MHz frequency that belongs to ultra-high frequency (UHF) band used in Malaysia with the center frequency of 910MHz. One rectangular slot and two triangle-shaped slots are used in designing this antenna. A good circular polarization obtained from the slotted structure along the diagonal axis in the design. RF pin diodes are used as the switching mechanism of the antenna. However, in this work to proof the concept of switching mechanism, copper pins are used as artificial switches. Parasitic elements are deployed on the right and left side of the driven element to assist the radiation pattern reconfiguration. Overall, the proposed antenna able to steer the beam at approximately at -30 , -16 , and 10 with peak gain of 3.2dB and average gain of 2.5dB. With this result, overall coverage of UHF RFID reader antenna could be improved.

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Beam Steering Monopole Antenna for Low Power Wireless Communication in WSN

2020-03-20 , Mahdir N.A.F. , Osman M.N. , Thennarasan Sabapathy , Muzammil Jusoh , Zainudin N.A.F.M.

Antenna for wireless sensor networks (WSN) application need to satisfy a number of additional properties like antenna efficiency. Since there are many WSN nodes, the use of low cost and high efficient antenna is highly important. Therefore, in this paper, a beam steering antenna resonate at 2.4 GHz with monopole element by using parasitic array technique is proposed. The parasitic array element is introduced to achieve a better gain and acts as a reflector to steer the beam to the desired degree of angles. The structure of the proposed design consists of monopole antenna as the radiating element, and to parasitic patches with the same dimension of monopole are placed next to the radiating patch. Two switches (PIN diode) are used and embedded at the back of the structure. By activating and deactivating of the switches (ON or OFF), the parasitic is either grounded or disconnected from ground. Consequently, depending on the switches configuration, the beam pattern can be steered two direction angles which 25 left or right. The simulated and measured results are presented to demonstrate the performance of the proposed antenna.

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A multilayered acoustic signal generator for low power energy harvesting

2017-10-10 , Awal M.R. , Muzammil Jusoh , Hasliza A Rahim @ Samsuddin , Thennarasan Sabapathy , Mohamed Nasrun Osman , Mohd Ilman Jais , Kamarudin M.R.

This paper presents the design and analysis of a multilayer cantilever to harvest vibration energy by generating acoustic signal. To do so, a five layer configuration is used to design the cantilever. Lead Zirconate Titanate (PZT-8), Stainless Steel 405 Annealed, Aluminum and Zinc Oxide are used to develop the layers. Water is used as the medium to analyze the sound propagation pattern. Sound Pressure Level, displacements and electric potential of the cantilever are analyzed along with other parameters. From the results, it is evident that, the proposed cantilever can propagate sound within a range of 78.7 dB to 73.4 dB in a 50 mm spherical distance.

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Reliable Early Breast Cancer Detection using Artificial Neural Network for Small Data Set

2021-03-01 , Vijayasarveswari V. , Muzammil Jusoh , Thennarasan Sabapathy , Rafikha Aliana A Raof , Khatun S. , Iszaidy I.

This paper proposes a breast cancer detection module using Artificial Neural Network for small data set. The developed system consists of hardware and software. Hardware included UWB transceiver and a pair of home-made directional sensor/antenna. The software included a Graphical User Interface (GUI) and k-fold based feed-forward back propagation Neural Network module to detect the tumor existence, size and location along with soft interface between software and hardware. Forward scattering technique is used by placing two sensors diagonally opposite sides of a breast phantom. UWB pulses are transmitted from one side of phantom and received from other side, controlled by the software interface in PC environment. Firstly feed forward backpropagation neural network (FFBNN) is developed. Then, k-fold is combined with developed FFBNN for testing purpose. Four data sets are created where contains 125, 95, 65 and 30 data samples in 1st,2nd,3rd and 4th data set respectively. Collected received signals were then fed into the NN module for training, testing and validation. The process is done for all data sets separately. The system exhibits detection efficiency of tumor existence, location (x, y, z), and size were approximately 87.72%, 87.24%, 83.93% and 80.51% for 1st, 2nd, 3rd and 4th data set respectively. The proposed module is very practical with low-cost and user friendly. The developed breast cancer detection module can be used for large data samples as well as for minimum data samples.

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Self-Isolated Frequency Reconfigurable two-port MIMO Antenna for 5G Application

2024-01-01 , Angadi S. , Sharma Y. , Rghava S.N. , Thennarasan Sabapathy

In this work two-port multiple input multiple output (MIMO) antenna with self-isolation between antenna elements is presented. Initially, the proposed antenna is constructed as a single-port square-shaped radiating patch connected diagonally with a stub to operate the antenna in frequency reconfigurable mode. A 2×2 mm slot is cut at the middle part of the stub for implementing reconfigurability on the radiating patch to operate the antenna in multi-functional mode. Later the proposed antenna is converted to two-port frequency reconfigurable MIMO antenna that realizes an S11 below -10 dB intended for two resonant bands operating at 3.79 GHz (3.41-4.04 GHz) with pin-diode off-mode and 4.53 GHz (4.69-4.88 GHz) in on-mode with maximum peak realized gain of 4.93 dB at diode off-mode and 4.55 dB in pin diode on-mode. moreover, the gain is enhanced by 1.5 dB after converting to the two-port antenna. The two feeding ports of the proposed antenna are positioned orthogonal to each other to permit the antenna in self-isolation mode without connecting any de-coupling circuit and maintaining the mutual coupling (S21) below-21 dB in off-mode and -29.50 dB in diode on-mode. The distance between antenna elements is 0.12 λ0. In addition to that, two-port MIMO of envelope correlation coefficient (ECC), channel capacity loss (CCL), total active reflection coefficient (TARC), mean effective gain (MEG), and diversity gain (DG) are simulated. The designed antenna is applicable for 5G new radio (NR) bands of n48, n78 in off-mode, and n79 in on-mode respectively.

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Metamaterial cell-based superstrate towards bandwidth and gain enhancement of quad-band CPW-fed antenna for wireless applications

2020-01-02 , Al-Bawri S.S. , Islam M.S. , Wong H.Y. , Jamlos M.F. , Narbudowicz A. , Muzammil Jusoh , Thennarasan Sabapathy , Islam M.T.

A multiband coplanar waveguide (CPW)-fed antenna loaded with metamaterial unit cell for GSM900, WLAN, LTE-A, and 5G Wi-Fi applications is presented in this paper. The proposed metamaterial structure is a combination of various symmetric split-ring resonators (SSRR) and its characteristics were investigated for two major axes directions at (x and y-axis) wave propagation through the material. For x-axis wave propagation, it indicates a wide range of negative refractive index in the frequency span of 2–8.5 GHz. For y-axis wave propagation, it shows more than 2 GHz bandwidth of near-zero refractive index (NZRI) property. Two categories of the proposed metamaterial plane were applied to enhance the bandwidth and gain. The measured reflection coefficient (S11) demonstrated significant bandwidths increase at the upper bands by 4.92–6.49 GHz and 3.251–4.324 GHz, considered as a rise of 71.4% and 168%, respectively, against the proposed antenna without using metamaterial. Besides being high bandwidth achieving, the proposed antenna radiates bi-directionally with 95% as the maximum radiation efficiency. Moreover, the maximum measured gain reaches 6.74 dBi by a 92.57% improvement compared with the antenna without using metamaterial. The simulation and measurement results of the proposed antenna show good agreement.

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Investigation on the Effect of Deflected Ground Structure in Multi-Direction Steerable Antenna for WSN

2020-03-20 , Zainudin N.A.F.M. , Osman M.N. , Thennarasan Sabapathy , Muzammil Jusoh

In this paper, a multi-direction steerable radiation pattern antenna is designed and investigated, which operates at 2.45 GHz frequency. The radiation pattern reconfigurable is achieved by locating four parasitic elements surrounding the driving element at the centre. The artificial switches, are currently used to replace the ideal diode for proof of the concept, are inserted at the specific position on the parasitic element. By controlling the state ON/OFF of the switches, the parasitic is grounded via shorting pin, thus realizing the beam steering to be directed into four direction angles; right, left, upwards and downwards. In this research, an investigation on the effect of deflected ground plane on the steering angles has been carried out. With minimum numbers of switches deployed, the proposed antenna is a potential candidate to serve as a transmitting element in WSN applications.

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Design a hexagonal shape frequency reconfigurable antenna for new C-band 5G applications

2022-01-01 , Ganesh M. , Raghava N.S. , Thennarasan Sabapathy

In this Communication, a simple hexagonal shape frequency reconfigurable antenna is designed with reduced ground plane for new C-band 5G (3.7GHz-3.98GHz applications. To enable frequency reconfiguration a PIN diode is adopted in the reduced ground plane with a gap size of 1mm. When diode is in OFF state the designed antenna resonates at 3.6 GHz with a bandwidth of 760 MHz, range used for Wi-Max and in ON state the designed structure resonates at 3.8 GHz with a bandwidth of 930 MHz, range used for New C-band 5G networks. The designed structure of an antenna is etched on a Fr-4 substrate with a size of 38X36X1.6mm3.

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