Wee Fwen Hoon
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Preferred name
Wee Fwen Hoon
Official Name
Hoon, Wee Fwen
Alternative Name
Fwen Hoon, Wee
Wee, F. H
Hoon, Wee Fwen
Main Affiliation
Scopus Author ID
57215069158
Researcher ID
CFL-8965-2022

Research Output

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  • Publication
    Parametric studies on effects of defected ground structure (DGS) for dual band bandstop microstrip filter
    ( 2017-11-22)
    Farah Shazuani Mahmud
    ;
    Mohammad Shahrazel Razalli
    ;
    Hasliza A Rahim @ Samsuddin
    ;
    Wee Fwen Hoon
    ;
    Mohd Zaizu Ilyas
    A dual-band bandstop microstrip filter is proposed and designed by using microstrip resonator with Defected Ground Structure (DGS). The DGS are placed in the ground plane to obtain high attenuation of the bandstop filter response. The proposed is designed by using R04003C printed circuit board with dimension of 38 mm x 20 mm. Simulated result shows an insertion loss of -12.31 dB, a return loss at -1.75 dB for center frequency at 2.4 GHz and insertion loss of -22.93 dB, a return loss of -0.78 dB for center frequency at 5.8 GHz The results of simulated in different parameters of DGS is analysed and discussed.
  • Publication
    Flexible Co-Planar Waveguide (CPW)-Fed Y-Shaped Patch UWB Antenna for Off-Body Communication
    ( 2020-03-18)
    Kassim S.
    ;
    Hasliza A Rahim @ Samsuddin
    ;
    Soh Ping Jack
    ;
    Abdulmalek M.
    ;
    Muzammil Jusoh
    ;
    Jamaluddin M.H.
    ;
    Sabli N.S.
    ;
    Yassin M.N.
    ;
    Thennarasan Sabapathy
    ;
    Wee Fwen Hoon
    ;
    Mohamed Nasrun Osman
    ;
    Ismail N.
    This paper intends to design an Ultra-Wideband (UWB) antenna for future Internet of Things (IoT) applications for off-body Wireless Body Area Networks (WBAN) communication. An antenna based on the Y-shaped patch fed using co-planar waveguide (CPW) line, with a full ground plane is designed. It is implemented on two different substrates, namely a 5mm thick Rogers RO4350B and a 5-mm-thick felt textile. Parametric analysis of antenna is performed by changing its critical dimensions and monitoring parameters such as gain, bandwidth, efficiency, radiation pattern when using both substrates. Besides that, the bending effects towards reflection coefficient and radiation patterns are also studied. The final patch size with the Y-shaped slot is 36 × 40 mm2 for both substrates. The antenna is capable of providing coverage for the bands from 8 to 10 GHz. Finally, the antenna designed on RO4350B substrate outperforms the antenna designed on felt by about four times in terms of bandwidth, with 3.3 GHz (7.7-11 GHz).
  • Publication
    Beam controller antenna for WiMAX application
    ( 2017-01-01)
    Leong Lim Wai
    ;
    Wee Fwen Hoon
    ;
    Yeow You Kok
    ;
    Mohd Fareq Abdul Malek
    ;
    Yew Lee Chia
    ;
    Seng Lee Yeng
    ;
    Siti Julia Rosli
    Introduce a practical design of an antenna that able to control the radiation beam pattern by using PIN diode and capacitor. The operation of the antenna is an on/off switch that controlled by PIN diode and Direct Current (DC) that supply from an an external source. The proposed antenna was verified to be able to cover the direction of 90 degreess when the DC is turn on. The DC pass through the PIN diode and activate the diode to be functioned as a switch. This proposed antenna is operated at a frequency of 2.3 GHz which is for Worldwide Interoperability for Microwave Access (WiMAX) application that symbolizes in the IEEE 802.16 family. This antenna is designed using a FR-4 substrate material with the dimension is 200 mm×200 mm using Computer Simulation Technology Microwave Studio (CST MWS) simulator software.
  • Publication
    Enhanced microwave absorption of rice husk‐based pyramidal microwave absorber with different lossy base layer
    (The Institution of Engineering and Technology, 2020)
    Lee Yeng Seng
    ;
    Soh Ping Jack
    ;
    You Kok Yeow
    ;
    Wee Fwen Hoon
    ;
    Lee Chia Yew
    ;
    Gan Hong Seng
    ;
    Fareq Malek
    The size of pyramidal microwave absorbers (PMA) is one of the main considerations for their selection for use in anechoic chambers. In this work, a new type of PMA is introduced, with rice husk (RH) as its filler. Meanwhile, a lossy base layer is also introduced in the PMA using a combined RH and carbon nanotube (CNT) composite. To do so, the dielectric properties of the RH‐CNT composite are first investigated from 2–18 GHz by using a dielectric probe. Next, the microwave absorption properties of the PMA were investigated in terms of different height of the pyramidal structure and base layer. The free‐space method was used to measure the microwave absorption of PMA at oblique incident angles of 0° to 60°, respectively. Results indicated good microwave absorption characteristics in the 2–6 GHz with a height of 11.5 cm the PMA structure, and 1 cm thickness of the base layer. The lossy base layer is found to increase the bandwidth of the absorber and improve the microwave absorption of PMA in the lower GHz frequencies. Further investigations concluded that the microwave absorption performance of the PMA is dependent on its dielectric properties, size and base layer.
  • Publication
    An ultrawideband full flexible 4 elements DGS based MIMO antenna for Sub-6 GHz wearable applications
    (IEEE, 2024-03)
    Bikash Chandra Sahoo
    ;
    Azremi Abdullah Al-Hadi
    ;
    Saidatul Norlyana Azemi
    ;
    Surentiran Padmanathan
    ;
    Sadia Afroz
    ;
    Wee Fwen Hoon
    ;
    Soh Ping Jack
    ;
    Che Muhammad Nor Che Isa
    ;
    Soumya Ranjan Mishra
    In this article, a compact wearable quad element MIMO antenna is presented operating at 4.5 GHz for 5G n77, n78, and n79 bands with the use of polyester substrate with a size of 80 × 82 × 0.4 mm3. Here T-shaped defected ground structure (DGS) technique has been utilized to improve the impedance bandwidth along with the reduction of the mutual coupling between the radiating elements. The antenna is evaluated in terms of reflection coefficient, gain, efficiency, and radiation pattern. The proposed MIMO antenna attained a maximum simulated gain of 4.3 dBi, and an efficiency of 96 % in the resonating band.
  • Publication
    Compact full flexible vivaldi antenna for 3.5 GHz wearable applications
    (IEEE, 2023)
    Bikash Chandra Sahoo
    ;
    Azremi Abdullah Al-Hadi
    ;
    Saidatul Norlyana Azemi
    ;
    Wee Fwen Hoon
    ;
    Surentiran Padmanathan
    ;
    Sadia Afroz
    ;
    Che Muhammad Nor Che Isa
    ;
    Yen San Loh
    ;
    Muhammad Syahir Mahyuddin
    ;
    Lai Ming Lim
    ;
    Zambri Samsudin
    ;
    Idris Mansor
    ;
    Soh Ping Jack
    In this paper, a compact wearable Vivaldi antenna resonating at 3.5 GHz is proposed for 5G n77, and n78 bands. It is designed upon a flexible polyester substrate having dielectric constant (εr) of 1.34 and loss tangent (tan δ) of 0.005. The antenna parameters were optimized via parametric analyses using CST software with a size of 45 × 45 × 0.4 mm3 (length × width × height). The antenna is evaluated in terms of reflection coefficient, gain, efficiency, radiation pattern, and surface current density. This antenna attained a maximum simulated gain of 4.7 dBi, and an efficiency of 98 % in the resonating band.
  • Publication
    Improvement of triple-band bandstop filter performances by using parametric analysis on Defected Ground Structure (DGS) and mechanical properties of Geopolymer ceramic reinforced Sn-0.7Cu
    (IOP Publishing, 2020)
    Farah Shazuani Mahmud
    ;
    Mohammad Shahrazel Razalli
    ;
    Wee Fwen Hoon
    In this paper, the parametric analysis of the configuration defected ground structure (DGS) for triple-band bandstop filter is proposed. The defected ground structures are used to improve the selectivity and S-parameters losses of the bandstop filter response. The rectangular-shaped DGS are added to the ground of the band stop filter. Initially, the DGS is applied to the first resonator (at 2.45 GHz) of the BSF. Several positions of the DGS are simulated to obtain the best S-parameters and selectivity performances. The same method is implemented on the second and third resonators of the BSF to obtain better performance in S-parameters and selectivity. Finally, all three resonators with the best DGS position are combined into one BSF to obtain triple-band BSF frequency response. This filter is designed by using Roger 4003C with relative dielectric constant, = 3.38 and substrate thickness, H = 0.508 mm. The bandstop filter is modelled and simulated by using high frequency Electromagnetic Simulator (EM). Simulated result shows the insertion losses are, S21 = -23.2 dB (at 2.45 GHz), -16.7 dB (at 3.5 GHz) and -24.4 dB (at 5.2 GHz). The return losses are, S11 = -0.49 dB (at 2.45 GHz), -0.64 dB (at 3.5GHz), 0.49 dB (at 5.2 GHz). The results of different configurations of DGS is analysed and discussed.
      1  10
  • Publication
    Analysis of Dielectric Properties on Agricultural Waste for Microwave Communication Application
    ( 2017-12-11)
    Nurul Ain Zulkifli
    ;
    Wee Fwen Hoon
    ;
    Norfadila Mahrom
    ;
    Been Seok Yew
    ;
    Yeng Seng Lee
    ;
    Siti Zuraidah Ibrahim
    ;
    Anusha Leemsuthep Am Phan
    This paper presents the analysis of dielectric properties of agricultural waste for microwave communication application such as microwave absorber and antenna. The residues products - rice straw, rice husk, banana leaves and sugar cane bagasse were studied in the range between 1-20GHz. Firstly, the 2 types of resins namely Epoxy der 331 and Polyamine clear hardener were mixed with the agricultural waste materials to produce the small size of agricultural waste sample. Then, the sample were measured using PNA network analyzer. The permittivity and tangent loss of different agricultural waste samples have been measured using dielectric probe technique. Besides, other objectives of this paper is to replace the conventional printed circuit board (PCB) using FR4, Taconic, and Roger material with the agricultural waste material. Besides that, the different percentage of filer for each agricultural waste materials were also investigated to specify the best material to be used as the substrate board and as the resonant material. the result shows the average of dielectric constants and the average of the tangent loss of agricultural waste materials.
      3  17
  • Publication
    Coconut shell, coconut shell activated carbon and beta-silicon carbide reinforced polymer composite: an alternative dielectric material for wireless communication application
    (Institute of Advanced Engineering and Science (IAES), 2020)
    Been Seok Yew
    ;
    Martini Muhamad
    ;
    Saiful Bahri Mohamed
    ;
    Wee Fwen Hoon
    The effect of coconut shell (CS), coconut shell activated carbon (CSAC) and beta-silicon carbide (β-SiC) in polymer composites was investigated. Elemental composition, surface morphologies and structural analyses of the fillers were performed using carbon, hydrogen, nitrogen and sulfur (CHNS) analyser, scanning electron microscope (SEM) and X-ray Diffractometer (XRD). The dielectric properties of the composites were measured using open-ended coaxial line method. CS and CSAC fillers had positive influence on the dielectric properties (ε’, ε” and σ) of the polymer composites, contributed by the orientation polarizations arises from polar nature of the amorphous CS and CSAC fillers. β-SiC filler had insignificant influence on the dielectric properties of the polymer composites due to its single polarization of the crystalline structure filler. This finding is in agreement with XRD patterns of CS and CSAC fillers that revealed the presence of amorphous structure with broad diffraction peaks that were detected at 2ϴ=22.236°, 34.8604° and 2ϴ=23.985° and 44.015°, respectively. The amorphization structure in the polymer composites allows the displacement and conduction currents that were induced from electric field to flow through the polymer composites when subjected to electromagnetic energy, thus increased the dielectric properties of the composites.
      6  1
  • Publication
    Flexible RFID Tag Antenna Design
    ( 2020-01-01)
    Wee Fwen Hoon
    ;
    Abdul Malek M.F.
    ;
    Yew B.S.
    ;
    Lee Y.S.
    ;
    Ibrahim S.Z.
    ;
    Hasliza A Rahim @ Samsuddin
    This research is to design a radio frequency identification (RFID) high sensitivity tag antenna which operates at UHF frequency band (919–923 MHz). The major problem in designing the tag antenna is that it needs to be designed for long-range transmission with a miniaturized size. However, reducing the size of the tag antenna can cause the gain to be decreased. Another challenge in designing RFID passive tag is to ensure no huge change occurs on the resonant frequency when the tag antenna is being bent. This research had provided two methods in overcoming those problems that include the construction of a meander line structure to reduce the antenna size that can be applied to a small device. In addition, flexible substrate, polyethylene terephthalate (PET) had been chosen for tag antenna. Thus, the expected result shows high gain (1.55 dB) with a small size of flexible tag antenna.
      13  1