Browsing by Author "Jamaluddin, M. H."

Now showing 1 - 4 of 4
  • Thumbnail Image
    ItemOpen Access
    Complementary split ring resonator for isolation enhancement in 5G communication antenna array
    (Electromagnetics Academy, 2018-04-24) Selvaraju, R.; Jamaluddin, M. H.; Kamarudin, Muhammad Ramlee; Nasir, J.; Dahri, M. H.
    A square-shaped complementary split ring resonator (CSRR) filtering structure for isolation improvement is presented in this paper. The proposed research work investigates the design and development of a simple and compact CSRR structure. In order to verify the performance of the proposed filtering element and improve the isolation among the closely placed antenna elements, arrays of configured CSRR structures are implemented between two antenna elements. An array of configured CSRR elements has been integrated with the printed antenna on the top and bottom layers. The proposed filtering elements offer an enhancement in isolation by 25 dB as compared to the simple array. The entire configuration has been simulated using the Ansoft HFSS simulator. Finally, the proposed design is fabricated and experimentally validated. In the experiment, coupling suppression of -51 dB at the operating frequency is successfully achieved, resulting in a recovery of the array pattern. The proposed antenna is highly efficient, which is suitable to be utilized for 5G communication.
  • Thumbnail Image
    ItemOpen Access
    Mutual coupling reduction and pattern error correction in a 5G beamforming linear array using CSRR
    (IEEE, 2019-10-01) Selvaraju, R.; Jamaluddin, M. H.; Kamarudin, Ramlee
    A four-element printed antenna array operating at 25 GHz frequency with complementary split ring resonator. (CSRR) has been proposed for beamforming applications. The CSRR elements has been used to suppress the mutual coupling in the proposed array. The existence of the CSRR configuration in antenna array, controls the unnecessary surface current flow between the array elements, thus the mutual coupling between array elements has been significantly reduced up to -55 dB. The effect of mutual coupling on the array radiation patterns has been studied in the presence and absence of CSRRs. The effectiveness of CSRR has been studied by steering the main beam as well as the nulls in different angles. By implementing the CSRR elements in array antenna, the distorted array patterns have been recovered and are presented. The proposed antenna array with the CSRR has the advantage of easy and low-cost fabrication and it offers excellent coupling suppression without changing the antenna profile. The commercially available simulation tools such as Matlab and Ansys HFSS have been used for array weights calculation and antenna design respectively. Finally, the fabricated prototype has been experimentally verified, and it shows that the analytical and computed results agree well with the measured results.
  • Thumbnail Image
    ItemOpen Access
    A review of wideband reflectarray antennas for 5G communication systems
    (IEEE, 2017-08-31) Dahri, M. H.; Jamaluddin, M. H.; Inam, M.; Kamarudin, M. R.
    The advancement in the current communication technology makes it incumbent to analyze the conventional features of reflectarray antenna for future adaptability. This work thoroughly reviews the design and experimental features of reflectarray antenna for its bandwidth improvement in microwave and millimeter wave frequency ranges. The paper surveys the fundamental and advanced topologies of reflectarray design implementations which are needed particularly for its broadband features. The realization of its design approaches has been studied at unit cell and full reflectarray levels for its bandwidth enhancement. Various design configurations have also been critically analyzed for the compatibility with the high frequency 5G systems.
  • Thumbnail Image
    ItemOpen Access
    Steerable Higher-order Mode Dielectric Resonator Antenna with Parasitic Elements for 5G Applications
    (IEEE, 2017-10-12) Shahadan, N. H.; Jamaluddin, M. H.; Kamarudin, M. R.; Yamada, Y.; Khalily, M.; Jusoh, M.; Dahlan, S. H.
    This paper presents the findings of a steerable higher-order mode (TEy 1δ3) dielectric resonator antenna with parasitic elements. The beam steering was successfully achieved by switching the termination capacitor on the parasitic element. In this light, all of the dielectric resonator antennas (DRAs) have the same dielectric permittivity similar to that of 10 and was excited by a 50Ω microstrip with a narrow aperture. The effect of the mutual coupling on the radiation pattern and the reflection coefficient, as well as the array factor were investigated clearly using MATLAB ver. 2014b and ANSYS HFSS ver. 16. As the result, the antenna beam of the proposed DRA array managed to steer from -32° to +32° at 15 GHz. Furthermore, the measured antenna array showed the maximum gain of 9.25 dBi and the reflection coefficients which are less than -10 dB with the bandwidth more than 1.3 GHz, which is viewed as desirable for Device-to-Device communication (D2D) in 5G Internet of Things (IoT) applications.