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Hasliza A Rahim @ Samsuddin
Preferred name
Hasliza A Rahim @ Samsuddin
Official Name
A Rahim @ Samsuddin, Hasliza
Alternative Name
A. Rahim, Hasliza
Rahim, Hasliza A.
Rahim Samsuddin, H. A.
Rahim, Hasliza Abdul
Rahim, Hazliza A.
Rahim, H. A.
Rahim, H.
Hasliza,
Rahim H, Abd
RahimAtSamusuddin, Hasliza A.
A Rahim, Hasliza
Rahim At Samsuddin, Hasliza A.
ARahim, H.
Rahim Samsuddin, A. Hasliza
Rahim At Samsuddin, H. A.
Rahim, Hasliza Abd
Rahim, Hasliza
Rahim At Shamsuddin, H. A.
Main Affiliation
Scopus Author ID
57202496362
Researcher ID
ABE-3328-2020
Now showing
1 - 10 of 16
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PublicationTwo layered 2 × 1 Koch curve patch array antenna with suspended air gap effect for wireless LAN applications( 2017-11-20)
;Abdulmalek M. ;Nornikman H. ;Al-Khatib O. ;Badrul Hisham Ahmad ;Abdulaziz N. ;Mohamad Zoinol Abidin Abd Aziz ; ;Ann N.Y. ;Shen J.Y.L. ;Salman N. ;Razak N.M.Bakar H.A.This paper proposed a two layered 2 × 1 Koch Curve patch array antenna design with suspended air gap technique for Wireless Local Area Network (WLAN) application of 2.4 GHz resonant frequency. This proposed patch antenna is using two FR-4 substrate layers with dielectric constant, εr = 4.4 and the electrical conductivity tangent loss, tanΔ = 0.019. It is using the suspended air gap technique between two layers for enhancement effect of antenna gain from 4.89 dB to 5.18 dB. At the upper part of substrate, it consists a two feeding networks that connected the two patch of Koch Curve array patch. Beside antenna gain, this technique also improves the bandwidth and return loss of the antenna. It also contains a Koch Curve array structure at the patch part and have a full ground of copper at the back. This Koch Curve is design based on the basic equilateral triangle with three iteration steps. For the first iteration step, it be made up of the equilateral triangular shaped while the second iteration are added with mirror design of equilateral triangular to create a six segment of star-shaped. For the third iteration step, the equilateral triangle with the length base on previous iteration step is constructed on top of the side line of the base triangle. This third iteration step of the Koch Curve effect the reduction size of the patch antenna from 100 mm × 100 mm to only 90 mm × 60 mm. The return loss performance at resonant frequency 2.4 GHz is −32.735 dB. -
PublicationA modified antipodal vivaldi antenna (AVA) with elliptical slotting edge (ESE) for ultra-wideband (UWB) applications( 2017-11-20)
;Nornikman H. ;Abdulmalek M. ;Ahmad B.H. ;Al-Khatib O. ;Aziz M.Z.A.A. ; ;Soon Y.Y. ;Muslimah M.S. ;Syazwany R. ;Salimi H.I. ;Amirul M.Y.Azizi M.S.N.As the demand of UWB system increases nowadays, several types of hybrid technique on antenna design are studied, modified, and proposed for UWB applications. In this work, an enhanced performance of modified antipodal Vivaldi antenna (AVA) for targeting ultrawideband (UWB) frequency range between 2.17 GHz and 10.6 GHz has been proposed. This proposed UWB antenna is using FR-4 substrate with dielectric constant, εr = 4.4 and the electrical conductivity tangent loss, tanΔ = 0.019. This antenna design is based on the modified from the dual exponential tapered slot antenna (DETSA) with varying of the exponential flares design for obtain the best return loss of the antenna within the frequency bandwidth of the UWB. It has two exponential flares that follow the characteristic of exponential curve. Next, an elliptical slotting edge (ESE) with fixed horizontal radius and varied vertical radius is implemented to the antenna which effectively increases the performance of the antenna at lower frequencies. These modifications are done without changing the antenna size, which is 70 mm × 90 mm in dimension, which is approximately 0.5λ × 0.6λ, where λ is the wavelength of 2 GHz. The effects of the parameters of the antenna characteristic are also studied. In this case, the parametric study on varying distance between elliptical slots, Ks. It shows that, the higher value of Ks will effect to shift to the resonant frequency and increase the return loss of the antenna. At 9.104 GHz of resonant frequencies, it shows of the best return loss of 48.809 dB. Rather than that, the side lobe levels of the radiation pattern of the antenna are reduced in the lower frequencies. -
PublicationA novel unsupervised spectral clustering for pure-tone audiograms towards hearing aid filter bank design and initial configurations( 2022-01-01)
;Elkhouly A. ; ; ;Abdulaziz N. ;Abdulmalek M. ; ; ;Siddique S.The current practice of adjusting hearing aids (HA) is tiring and time-consuming for both patients and audiologists. Of hearing-impaired people, 40–50% are not satisfied with their HAs. In addition, good designs of HAs are often avoided since the process of fitting them is exhausting. To improve the fitting process, a machine learning (ML) unsupervised approach is proposed to cluster the pure-tone audiograms (PTA). This work applies the spectral clustering (SP) approach to group audiograms according to their similarity in shape. Different SP approaches are tested for best results and these approaches were evaluated by Silhouette, Calinski-Harabasz, and Davies-Bouldin criteria values. Kutools for Excel add-in is used to generate audiograms’ population, annotated using the results from SP, and different criteria values are used to evaluate population clusters. Finally, these clusters are mapped to a standard set of audiograms used in HA characterization. The results indicated that grouping the data in 8 groups or 10 results in ones with high evaluation criteria. The evaluation for population audiograms clusters shows good performance, as it resulted in a Silhouette coefficient >0.5. This work introduces a new concept to classify audiograms using an ML algorithm according to the audiograms’ similarity in shape. -
PublicationFlexible Co-Planar Waveguide (CPW)-Fed Y-Shaped Patch UWB Antenna for Off-Body Communication( 2020-03-18)
;Kassim S. ; ;Soh Ping Jack ;Abdulmalek M. ; ;Jamaluddin M.H. ;Sabli N.S. ;Yassin M.N. ; ; ;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). -
PublicationCo-planar waveguide (CPW) slotted bow-tie antenna with band-notch using polygon-shaped branches structure( 2017-11-20)
;Abdulmalek M. ;Nornikman H. ;Al-Khatib O. ;Abdulaziz N. ;Aziz M.Z.A.A. ;Ahmad B.H. ; ;Mustapha M.S. ;Muslihat M.M.D.M. ;York S.B. ;Yusof S.H.M.Nazim N.S.M.Nowadays, the world has rapidly evolved in the communication system in term of speed and information capacity. Thus, a bow-tie antenna is the suggestion to use because of its exhibits low profile and lightweight. However, the bow-tie patch antenna, inherently have narrow bandwidths and in general are half wavelength structures operating at the fundamental resonant mode. To cater this problem, a slotted bow-tie antenna is designed for wireless applications with consist techniques a pair of polygon-shaped branches structure is implemented on each arm of the bow-tie slot antenna characteristics. The co-planar waveguide is applied to this antenna to effect the wider bandwidth to the antenna. This proposed CPW slotted bow-tie antenna is using FR-4 substrate with dielectric constant, εr = 4.4 and the electrical conductivity tangent loss, tan Δ = 0.019 with substrate dimension of 52.4 mm length × 22.3 mm width. Several parametric studies are done to make sure the suitable dimension for best antenna performance. In this case, several different dimensions of three part are consider to study, such as the microstrip line width (Wml), height of feedline (Hfl), and the length of branch, Lbr. The basic antenna without polygon-shaped branches can offer a wider frequency band operation at 2.293 GHz-2.541 GHz with bandwidth of 248 MHz effect by the co-planar waveguide technique. After the addition of the polygon-shaped branches structure to the bow-tie part, its effect a band-notch effect at the 2.46 GHz, while creating a new resonant frequency at two different part at 2.394 GHz and 2.511 GHz with resonant frequency of −18.585 dB and 19.555 dB, respectively.25 2 -
PublicationEvaluation of a broadband textile monopole antenna performance for subject-specific on-body applications( 2017-01-01)
; ;Abdulmalek M. ;Soh Ping JackGuy A. E. VandenboschThe human body characteristics with different dimensions and tissue properties are one of the major factors in influencing the on-body radio propagation channel characteristics. A broadband textile monopole antenna operating at 2.45 GHz is evaluated to validate its performance on different subjects’ characteristics. The results show that the textile monopole antenna is sufficiently robust against the variations introduced by the body up to 0.9 and 0.2% changes in the antenna’s impedance matching level and resonant frequency shift when evaluated 10 mm from the body.15 1 -
PublicationA hybrid modified method of the sine cosine algorithm using latin hypercube sampling with the cuckoo search algorithm for optimization problems( 2020-11-01)
; ; ; ;Yahaya N.Z. ; ; ;Abdulmalek M. ; ; ;The metaheuristic algorithm is a popular research area for solving various optimization problems. In this study, we proposed two approaches based on the Sine Cosine Algorithm (SCA), namely, modification and hybridization. First, we attempted to solve the constraints of the original SCA by developing a modified SCA (MSCA) version with an improved identification capability of a random population using the Latin Hypercube Sampling (LHS) technique. MSCA serves to guide SCA in obtaining a better local optimum in the exploitation phase with fast convergence based on an optimum value of the solution. Second, hybridization of the MSCA (HMSCA) and the Cuckoo Search Algorithm (CSA) led to the development of the Hybrid Modified Sine Cosine Algorithm Cuckoo Search Algorithm (HMSCACSA) optimizer, which could search better optimal host nest locations in the global domain. Moreover, the HMSCACSA optimizer was validated over six classical test functions, the IEEE CEC 2017, and the IEEE CEC 2014 benchmark functions. The effectiveness of HMSCACSA was also compared with other hybrid metaheuristics such as the Particle Swarm Optimization–Grey Wolf Optimization (PSOGWO), Particle Swarm Optimization–Artificial Bee Colony (PSOABC), and Particle Swarm Optimization–Gravitational Search Algorithm (PSOGSA). In summary, the proposed HMSCACSA converged 63.89% faster and achieved a shorter Central Processing Unit (CPU) duration by a maximum of up to 43.6% compared to the other hybrid counterparts.10 46 -
PublicationUWB Antenna with Artificial Magnetic Conductor (AMC) for 5G Applications( 2020-01-01)
;Syuhaimi Kassim ; ;Abdulmalek M. ; ;Jamaluddin M.H. ; ;Mohsin D.A. ;Yahya N.Z. ; ;Rani K.N.A.This paper presents the design of an ultra-wideband (UWB) antenna for Internet of Things (IoT) applications that operate within 5G operating frequencies. One of the IoT-based devices’ architecture is wireless body area networks (WBANs). WBAN allows computer device to communicate with human body signal by trading digital information like electrical conductivity. Fifth generation (5G) is the state-of-the-art generation mobile communication. A higher data speed it offers will improve data communication efficiency in WBAN system. One of the biggest challenges foreseen for the wearable UWB antenna is the antenna bandwidth. The challenge is to warrant a wideband performance throughout the operating frequency, and a trade-off with a high dielectric in proposed substrate is essential. This paper presents design and parametric analysis of an antenna using a typical industry-preferred Rogers material (RO4350B) substrate with wider bandwidth as compared to 5G frequencies, 10.125–10.225 GHz. This paper also exhibits bandwidth improvement with the presence of artificial magnetic conductor (AMC) as a metasurface. A typical UWB patch antenna was initially designed before being integrated with AMC through a parametric analysis. This paper analyzes the frequency, gain, directivity and antenna efficiency before and after optimization. This paper successfully demonstrates a slotted Y-shaped antenna design with coplanar waveguide (CPW) using a Rogers material (RO4350B) as a substrate and the bandwidth improvement by 15.6% with the AMC as a metasurface.32 2 -
PublicationCo-planar waveguide (CPW) patch antenna with octagonal-shaped ring for WiMAX application( 2017-11-20)
;Nornikman H. ;Abdulmalek M. ;Mohamad Zoinol Abidin Abd Aziz ;Badrul Hisham Ahmad ;Al-Khatib O. ; ;Md Daud A.A.A. ;Yee L.Y. ;Tahir M.A.Z.M. ;Yoong W.L. ;Rosdin M.F.Bakar H.A.WiMAX (Worldwide Interoperability for Microwave Access) is a part of wireless communication standards based on the IEEE 802.16 set of standards. In this work, a co-planar waveguide (CPW) patch antenna with octagonal-shaped ring had been design for WiMAX application of 3.5 GHz. This proposed CPW antenna is using FR-4 substrate with dielectric constant, εr = 4.4 and the electrical conductivity tangent loss, tan Δ = 0.019. There are three stages of the antenna design that consist the Design A - basic rectangular patch antenna, the Design B - rectangular patch antenna with octagonal-shaped ring while the last stage is Design C -rectangular patch antenna with octagonal-shaped ring with CPW effect. A parametric study of CPW length, LCPW had been done to make sure the best return loss performance and the location of the resonant frequency near to WiMAX frequency range. In this case, nine different dimensions of LCPW that considers is from 11 mm to 19 mm. It shows that the LCPW = 18 mm shows the resonant frequency of T 3.528 dB. The CPW patch antenna with octagonal-shaped ring effect a wider bandwidth and create two resonant frequencies. It shows that the proposed antenna covers from the 2.282 GHz to 4.216 GHz, with bandwidth of 1.978 GHz, improve from Design A and Design B of 0.11 GHz and 0.73 GHz, respectively. Two resonant frequencies are located at 2.59 GHz and 3.528 GHz with return loss of −23.89 dB and −34.78 dB, respectively. The antenna gain of Design C is improve to 2.92 dB, after the addition of the CPW technique.1 16 -
PublicationA Hybrid Mutual Coupling Reduction Technique in a Dual-Band MIMO Textile Antenna for WBAN and 5G Applications( 2021-01-01)
;Hamza A. Mashagba ; ; ;Jamaluddin M.H. ; ; ; ;Abdulmalek M. ; ;Soh Ping JackThis paper presents a hybrid mutual coupling reduction technique applied onto a dual-band textile MIMO antenna for wireless body area network and 5G applications. The MIMO antenna consists of two hexagonal patch antennas, each integrated with a split-ring (SR) and a bar slot to operate in dual-band mode at 2.45 GHz and 3.5 GHz. Each patch is dimensioned at 47.2 × 31 mm2. This hybrid technique results in a simple structure, while enabling significant reduction of mutual coupling (MC) between the closely spaced patches (up to 0.1 λ). This technique combines a line patch and a patch rotation technique, explained as follows. First, a line patch is introduced at an optimized distance to enable operation with a broad impedance bandwidth at both target frequencies. One of the patches is then rotated by 90° at an optimized distance, resulting in a significant MC suppression while maintaining the dual and broad impedance bandwidth. The proposed MIMO antenna is further evaluated under several bending configurations to assess its robustness. A satisfactory agreement between simulated and measured results is observed in both planar and bending conditions. Results show that the MIMO antenna achieves an impedance bandwidth of 4.3 % and 6.79 % in the 2.45 GHz and 3.5 GHz band, respectively. Moreover, very low MC (S21 <-30 dB) is achieved, with a low (< 0.002) envelop correlation coefficient, and about 10 dB of diversity gain at both desired frequencies using this technique. Even when bent at an angle of 50° at the x-and y-axes, the antenna bent maintained a realized gain of 1.878 dBi and 4.027 dBi in the lower and upper band, respectively. A robust performance is offered by the antenna against the lossy effects of the human body with good agreements between simulated and measured results.2 29