Browsing by Author "Raghavan, Singaravelu"

Now showing 1 - 6 of 6
  • No Thumbnail Available
    Item
    Compact QMSIW based antennas for WLAN/WBAN applications
    (Electromagnetics Academy, 2018-03-28) Chaturvedi, Divya; Raghavan, Singaravelu
    In this paper, two compact planar substrate integrated waveguide (SIW) cavity-backed antennas are proposed for wireless local area network (WLAN) at 5.5GHz and wireless body area network (WBAN) at 5.8GHz. The miniaturization is achieved with the concept of quarter-modetopology, and the size of the cavity is reduced up to one-fourth of the circular SIW cavity. A L-shaped slot is etched on the top plane for miniaturization, and antenna-1 is realized which resonates at 5.5GHz. A metal strip has been added in the middle section of the slot, and antenna-2 is realized, which resonates at 5.8GHz. Both proposed antennas are tested in free space, while the performance of antenna-2 is investigated for on-body condition. In free space, the measured impedance bandwidths of the antenna are 160 MHz and 210MHz at 5.5 GHz and 5.8GHz, respectively. The radiation efficiency of the antenna is 89.4% in free space and 57% on phantom at 5.8GHz. Both measured and simulated results are observed, and they are in a good agreement.
  • No Thumbnail Available
    Item
    Design and analysis of open complementary split ring resonators loaded monopole antenna for multiband operation
    (Electromagnetics Academy, 2017-10-12) Daniel, Raphael Samson; Pandeeswari, Ramasamy; Raghavan, Singaravelu
    This paper describes a compact triple-band monopole antenna based on Open Complementary Split Ring Resonators (OCSRRs) for Wireless Local Area Network (WLAN) and Worldwide interoperability Microwave Access (WiMAX) applications. The monopole antenna with engraved ground plane is used to cover WLAN frequencies (2.67 GHz and 5.47 GHz). The resonant frequency of WiMAX (3.43GHz) is achieved by introducing OCSRR in the monopole antenna. In order to achieve multiband and good impedance matching, OCSRRs are introduced in the rectangular monopole antenna. The prototype antenna is fabricated on an FR-4 substrate having dimension of 29.4 × 26 × 1.6mm3. Simulated and measured results are shown in good equivalence. The dipole radiation pattern is obtained in the elevation plane (E-plane), and omnidirectional radiation pattern is obtained in the azimuthal plane (H-plane). Parametric analysis of OCSRRs is studied to attain the best results. The proposed antenna has adequate advantages, including compact size, multiband, and impedance matching.
  • No Thumbnail Available
    Item
    Design and analysis of open complementary split ring resonators loaded monopole antenna for multiband operation
    (Electromagnetics Academy, 2017-10-12) Daniel, Raphael Samson; Pandeeswari, Ramasamy; Raghavan, Singaravelu
    This paper describes a compact triple-band monopole antenna based on Open Complementary Split Ring Resonators (OCSRRs) for Wireless Local Area Network (WLAN) and Worldwide interoperability Microwave Access (WiMAX) applications. The monopole antenna with engraved ground plane is used to cover WLAN frequencies (2.67 GHz and 5.47 GHz). The resonant frequency of WiMAX (3.43GHz) is achieved by introducing OCSRR in the monopole antenna. In order to achieve multiband and good impedance matching, OCSRRs are introduced in the rectangular monopole antenna. The prototype antenna is fabricated on an FR-4 substrate having dimension of 29.4 × 26 × 1.6mm3. Simulated and measured results are shown in good equivalence. The dipole radiation pattern is obtained in the elevation plane (E-plane), and omnidirectional radiation pattern is obtained in the azimuthal plane (H-plane). Parametric analysis of OCSRRs is studied to attain the best results. The proposed antenna has adequate advantages, including compact size, multiband, and impedance matching.
  • No Thumbnail Available
    Item
    Design and Optimization of Substrate Integrated Waveguide Bandpass Filter with T-Shape Slots Using Artificial Neural Networks
    (Electromagnetics Academy, 2023-03-15) Rayala, Ranjit Kumar; Pandeeswari, Ramasamy; Raghavan, Singaravelu
    The present paper describes a substrate integrated waveguide (SIW) bandpass filter with a T-shape slot on the upper layer, which exhibits a wide-band frequency response. The parameters of the filter are optimized by using Multi-Layer Perceptron artificial neural network (MLP-ANN) that uses Levenberg-Marquardt (LM) algorithm. A comparison is made between ANN optimized results and simulated results, and they result in minimum mean square error (MSE). A physical prototype is fabricated using printed circuit board (PCB) process, and measurements are conducted using the network analyzer. The measured results obtained agree well with the estimated ones. The filter shows a wide-band response with a transmission bandwidth of 8.96 GHz, ranging from 6.10 to 15.06 GHz with a fractional bandwidth of 81.4%. Furthermore, the insertion loss of the filter in the entire passband is varied from −0.4 dB to −0.2 dB, and the return loss is more than −10 dB. © 2023, Electromagnetics Academy. All rights reserved.
  • No Thumbnail Available
    Item
    Metamaterial inspired structure with offset-fed microstrip line for multi band operations
    (Electromagnetics Academy, 2019-06-25) Murugeshwari, Balasubramanian; Daniel, Raphael Samson; Raghavan, Singaravelu
    A miniaturized rectangle-shaped complementary split ring radiating element with an offset-fed microstrip line is reported for multiband operations. The fabricated antenna with a compact size of 19×19×1.6 mm3 is designed on an FR-4 substrate with loss tangent tan δ = 0.02 and dielectric constant (εr) of 4.4. Multiband and antenna miniaturization are achieved by a complementary split ring radiating element, and it produces an impedance bandwidth of 40 MHz resonance at 3.03 GHz, 40 MHz resonance at 3.66 GHz, and 1470 MHz resonance at 5.5 GHz. The passband behaviour of the complementary split ring radiating element is studied in detail for obtaining multiband abilities of the miniaturized antenna. The metamaterial property of the complementary split ring radiating element is analyzed, by which the negative permittivity (ε) existence and the new resonance frequency are confirmed. The fabricated antenna shows optimum performance at the measured radiation characteristics. © 2019, Electromagnetics Academy. All rights reserved
  • No Thumbnail Available
    Item
    SRR-loaded metamaterial-inspired electrically-small monopole antenna
    (Electromagnetics Academy, 2018-01-25) Chaturvedi, Divya Send mail to Chaturvedi D.; Raghavan, Singaravelu
    In this paper, a CPW-fed compact metamaterial-inspired monopole antenna is proposed for Industrial, Scientific and Medical radio band (ISM, 2.4–2.483 GHz). The proposed antenna consists of a T-shaped patch and a set of split ring resonators (SRRs). The miniaturization is attained after loading SRRs in proximity to the T-shaped radiator, which makes the antenna structure electrically small. The measured fractional bandwidth of the antenna is 4% (2.42–2.52 GHz), and its size is 0.22λo 0.098λo ×.013λo. In addition, the electrically equivalent circuit of the proposed antenna is modeled, and the resonant frequency is calculated by using an analytical approach. Also, the permeability plot of SRRs is extracted using Nicolson Ross weir method. The measured peak gain and radiation efficiency of the antenna are obtained as 1.76 dBi and 78.5%. The simulated results and measured results are found in a good agreement.