Subhash B K
Bio: Subhash B K is an academic researcher from Reva Institute of Technology and Management. The author has contributed to research in topics: Radiation pattern & Ground plane. The author has an hindex of 2, co-authored 7 publications receiving 7 citations.
••02 Oct 2018
TL;DR: In this paper, a detailed analysis of two metamaterial unit cells through waveguide medium is presented, which exhibit stop-band phenomenon at 3.3GHz and 8.1GHz, respectively.
Abstract: In this research we present a detailed analysis of two metamaterial unit cell through waveguide medium. The first unit cell consists of four G-shaped resonators with split gap and thus named as G-shaped split ring resonator (GSRR). This unit cell exhibit stop-band phenomenon at 3.3GHz. The second unit cell is of Hexagonal shaped with split gaps, and thus named as, hexagonal split-ring resonator (HSRR). This unit cell exhibits stop-band phenomenon at 8.1GHz. Detailed analysis of extraction of medium parameters like permeability and refractive index for both metamaterial unit cells have been discussed in detail.
01 Sep 2018
TL;DR: A highly compact Toyota logo five band antenna loaded with pi and inverted L-shaped slots is proposed and good impedance matching, stable radiation pattern and radiation efficiency greater than 50% are achieved at the targeted frequencies.
Abstract: A highly compact Toyota logo five band antenna loaded with pi and inverted L-shaped slots is proposed. Compactness and the resonance at 3.38 GHz (WiMAX) in the design are achieved by inverted L-shaped slot. Pi-shaped slot controls the resonance at 5.88 (WLAN), 6.68 (Satellite band) and 9.28 GHz (X-band) whereas, the radiating patch (Toyota logo) controls the resonance at 8.24 GHz (X-band). The antenna has dimension of only (0.19λ 0 × 0.19λ 0 × 0.02λ 0 ) (λ 0 is the free space wavelength at 3.88 GHz). Good impedance matching, stable radiation pattern and radiation efficiency greater than 50% are achieved at the targeted frequencies.
••02 Oct 2018
TL;DR: In this paper, a compact metamaterial based antenna is proposed, which consists of a regular decagonal split ring resonator (RDSRR) as a radiating part and a feed line.
Abstract: A compact metamaterial based antenna is proposed in this research. The antenna has a compact area only 289 mm2 (17 × 17mm2).The antenna consists of metamaterial of regular decagonal split ring resonator (RDSRR) as a radiating part and a feed line. The metamaterial RDSRR analysis through waveguide medium has been discussed in detail. The antenna exhibits resonance at 6.5GHz with S11 <_10dB bandwidth of 120 MHz (6.46–6.58 GHz). A gain of 3 dBi, good impedance matching and stable radiation pattern at the operational bandwidths makes the proposed design suitable for satellite applications.
01 Sep 2018
TL;DR: In this article, the authors proposed a triple-band E-type unit cell DGS structure for WiMAX/WLAN applications, where each unit cell independently controls a set of bands (i.e., 2.5-2.64 GHz, 3.53-3.74 GHz, and 5.8-5.735 GHz).
Abstract: A compact (0.15 λ l ×0.15 λ l ×0.01λ l ) triple band antenna for WiMAX/ WLAN application is proposed. Compactness and multiband operation is accomplished by utilizing E-type unit cell Defected Ground Structure (DGS) in conjunction with H-shaped slot. The main advantages of the proposed E-type unit cell DGS structure is that each unit cell independently control a set of bands (i.e. Upper E-type unit cell DGS structure controls 2.56 and 3.64 GHz, while lower E-type unit cell controls the band at 5.8GHz). The antenna shows the resonance at 2.56 (lower WiMAX), 3.64 (middle WiMAX) and 5.8 (WLAN) with fractional bandwidth of about 5.44 % (2.5-2.64 GHz), 5.77% (3.53-3.74 GHz) and 1.5% (5.735.82 GHz). Good pattern and impedance matching is obtained at the targeted frequencies.
01 Sep 2018
TL;DR: A compact maple leaf shaped triple band antenna stacked with dodecagonal-shaped slot for WiMAX and satellite TV is proposed and exhibits good impedance matching, stable radiation pattern, acceptable gain and radiation efficiency greater than 65% at the targeted frequencies.
Abstract: A compact maple leaf shaped triple band antenna stacked with dodecagonal-shaped slot for WiMAX and satellite TV is proposed. The antenna consists of a maple leaf shaped radiating patch which makes the antenna to resonate at 3.72(WiMAX) and 6.76 GHz (satellite TV) frequency band. Operation at 6.16 GHz (satellite TV) in the proposed design is obtained by etching regular dodecagonal-shaped slot in the ground plane. The antenna has a dimension of only 0.27λ 0 × 0.27λ 0 × 0.01λ 0 (λ 0 is the free space wavelength at 3.72 GHz). The proposed design exhibits good impedance matching, stable radiation pattern, acceptable gain and radiation efficiency greater than 65% at the targeted frequencies.
TL;DR: The metamaterial design structure, SQM, successfully achieves the objectives of this research work and can be applied to multi band applications.
Abstract: This study explores the effect of symmetrical square shaped metamaterial design for microwave frequency applications. The latest technology demands of advanced performance and research studies of metamaterial integration in the related bands are increasing tremendously. Therefore, this motivates us to explore the metamaterial design structure that has a high possibility to be applied in more than two resonance bands using a compact design structure. This study emphasis on a compact 14 × 14 mm2 and 1.524 mm thick substrate material known as Rogers RT6002. Seven distinct square shaped metamaterial (SQM) rings were constructed on the substrate material to achieve the goal of this research study. Besides that, the investigations of the metamaterial electromagnetic properties and effective medium parameters were carried out by utilising the Computer Simulation Technology Microwave Studio (CST) software. According to the numerical simulation results, the proposed SQM unit cell manifested quintuple resonance frequencies precisely at 3.384 (S band), 5.436, 7.002 (C band), 11.664 (X band), and 17.838 GHz (Ku band). Meanwhile, for the validation process, the comparison between the simulation and measurement results was analysed and data showed that the first and third resonance frequencies were increased by 0.336 and 0.139 GHz, respectively while other frequencies were reduced by 0.186, 0.081, and 0.709 GHz in sequential order. The numerical simulation of the metamaterial design was conducted in a High Frequency Structure Simulator (HFSS) to further validate the results. Furthermore, the proposed SQM manifested left handed characteristics at the second to fifth resonance bands. In a nutshell, the SQM successfully achieves the objectives of this research work and can be applied to multi band applications.
01 Jul 2020
TL;DR: In this article, a penta band with complementary octagonal split ring resonator (COSRR) was proposed for Wi-MAX, WLAN, Satellite band and X-band applications.
Abstract: A penta band loaded with complementary octagonal split ring resonator (COSRR) is reported. The antenna has a size of 0.16λ l × 0.16λ l × 0.01λ l , at lower frequency band of 3.33 GHz. The antenna consists of a rectangular slot is placed in the ground plane and complementary octagonal split ring resonator in the radiating patch, which independently resonates lower frequency at 3.33 GHz and other four bands at 5.01GHz, 5.28GHz, 7.46GHz, and 9.48GHz respectively. The designed antenna operates at 3.33, 5.01, 5.28, 7.46 and 9.48 GHz. It is observed that the proposed structure is having better impedance matching, gain, efficiency and stable radiation pattern at targeted frequencies and used for Wi-MAX, WLAN, Satellite band and X-band applications.
••27 Sep 2021
TL;DR: In this article, an investigation of a dome-shape patch antenna for EMI wireless sensor purpose is presented, where the antenna has been deformed into three forms to investigate its performance when it is worn by user.
Abstract: Microstrip antenna is a popular planar antenna which is used in wide applications, including for EMI wireless sensor. It has small form factor and can be made from unique shapes. This paper presents an investigation of a dome-shape patch antenna for EMI wireless sensor purpose. It has two main structures which are the dome structure and the lower part structure. Some simulations have done to verify this antenna design performance such as its return loss, gain, and radiation pattern. It shows that the dome size contributes to the antenna frequency center while the lower part affects the return loss and bandwidth of the antenna. The antenna has been deformed into three forms to investigate its performance when it is worn by user. Overall, the deformation simulation results indicate there is no significant change regarding the initial design.
TL;DR: In this paper , a metamaterial unit cell is analyzed by modifying the geometric design of the metallic structure which mitigates the design to reduce the cost for the commercialization.
Abstract: Abstract In this research work, the development of the metamaterial unit cell is used to investigate multifunctional characteristics, exhibit preferable and capable adjustability, reconfigurable by changing the phase response of applied electromagnetic wave. This proposed metamaterial unit cell is analysed by modifying the geometric design of the metallic structure which mitigates the design to reduce the cost for the commercialisation. The resonant frequencies are located from 1.87, 2.55, 4.32, 5.46 GHz. The interaction with the electric field and magnetic field exhibit the polarisation in both planes which enhances the left handed characteristics. The field distribution of electric, magnetic, and surface current is presented with vector fields in different planes to observe the polarisation state. Different thicknesses of dielectric material are utilised to observe the impact of time varying electric and magnetic fields through the proposed metamaterial. The different substrate materials are described the degree of freedom for the implementation in different fields within the functional microwave frequency range.