Nor Azura Malini Ahmad Hambali
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Preferred name
Nor Azura Malini Ahmad Hambali
Official Name
Nor Azura Malini, Ahmad Hambali
Alternative Name
Hambali, N. A. M. Ahmad
Hambali, N. A. M. A.
Hambali, Nor Azura Malini Ahmad
Idris, N. A.
Hambali, N. Azura M. Ahmad
Main Affiliation
Scopus Author ID
27567626900
Researcher ID
JFK-8606-2023

Research Output

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  • Publication
    Geometrical optimization of lithium niobate on insulator rib waveguide for quantum communication application
    (AIP Publishing, 2020)
    Nor Roshidah Yusof
    ;
    Norshamsuri Ali @ Hasim
    ;
    P. Kolenderski
    ;
    Nor Azura Malini Ahmad Hambali
    ;
    Syed Alwee Aljunid Syed Junid
    Recently, thin film Lithium niobate has been recognized as an alternative material to silicon based technology due to its capability to support a broader range for quantum communication system. With the aim to operate within single photon application, we demonstrate the mode distribution, propagation constant and effective refractive indices of the Lithium Niobate on Insulator rib waveguide which operates at both fundamental wavelength, 1550 nm and second harmonic wavelength, 775 nm, respectively by using Finite Element Method. The etched depth and width of the core was varied from 340 to 400 nm and 700 to 1400 nm, respectively with the thickness of slab is fixed at 100 nm. From the result, it shows the effective refractive index increases gradually with the increment of etched depth and width of core, respectively. At second harmonic wavelength, the effective refractive indices and propagation constant shows a significant increment compare to observation at 1550 nm with an ability to produce both fundamental mode and first order mode across the structure.
  • Publication
    Two dimensional (2D) OCDMA encoder-decoder for various industrial application
    ( 2021-12)
    Syed Alwee Aljunid Syed Junid
    ;
    Mohd Arif Anuar Mohd Salleh
    ;
    A A M Ismail
    ;
    ND Keraf
    ;
    R Matem
    ;
    Mohd Rashidi Che Beson
    ;
    Norshamsuri Ali @ Hasim
    ;
    Mohd Shafiq Amirul
    ;
    Rosdisham Endut
    ;
    Nor Azura Malini Ahmad Hambali
    Future telecommunication systems and networks are expected to provide a variety of integrated broadband services to the customers. There has been a tremendous interest in applying Code Division Multiple Access (CDMA) techniques to fiber optic communication systems. This technique is one of the multiple access schemes that is becoming popular because of the flexibility in the allocation of channels, ability to operate asynchronously, enhanced privacy and increased capacity in bursty networks. This project is focusing on designing 2D OCDMA system with the hardware implementation of design using FPGA. The coding techniques in OCDMA are time versus wavelength and amplitude versus phase. 2D OCDMA coding incorporates both wavelength selection and time distribution. The data bit would be encoded as consecutive chips with various wavelengths. The code architecture seeks to produce codes with high autocorrelation and low cross-correlation properties. Code length is an essential aspect of code and device architecture for coding characteristics. The hardware implementation of the system is designed by using FPGA De1-SoC. The FPGA have the abilities to enhance the transmission of data to the receiver in a short period of time. The performance of 2D OCDMA system is expected to surpass 1D OCDMA system in terms of BER and the number of simultaneous users that can be supported. The system encoder and decoder were designed using optical switch, splitter, combiner and modulator. The performance of 2D OCDMA system in terms of time spreading and wavelength spreading is also compared which shown a huge difference in the results. The best performance of the system is when the number of wavelength (M) is fixed to 18 and the number of times spreading (N) is 31 which can support 350 more simultaneous users.
      2  15
  • Publication
    Modeling on impact of metal object obstruction in urban environment for internet of things application in vehicular communication
    ( 2020-01-08)
    Turner J.S.C.
    ;
    Azizi Harun
    ;
    Mohd Najib Mohd Yasin
    ;
    Norshamsuri Ali @ Hasim
    ;
    Shahriman Abu Bakar
    ;
    Fadzilla M.A.
    ;
    Sohiful Anuar Zainol Murad
    ;
    Nor Azura Malini Ahmad Hambali
    ;
    Razlan Z.M.
    ;
    Mohd Sani Mohamad Hashim
    ;
    Wan Khairunizam Wan Ahmad
    ;
    Phoon C.Y.
    Objects such as vehicles are considered one of challenging obstruction on the road and very little attention has been made to address its significance on the wireless signal. As such, this paper validates the impact of vehicle obstruction on signal propagation using received signal strength indicator (RSSI) based on the wireless channel measurements of realistic environmental obstruction at 2.4 GHz frequency band. Low mobility IEEE 802.15.4 XBee S2C compliant device which is designed to collect received signal power was used and these devices were deployed at area congested with cars. The channel measurements were conducted on LOS car parking area with two scenarios; single-sided and double-sided vehicle obstruction which mimics the obstruction of metal objects. The effect of existing vehicle on the signal propagation is demonstrated based on RSSI and RMSE. The attenuation profile of vehicular obstruction on wireless signal is modeled and compared with large-scale propagation models. Results show that metal object significantly reduce transmission range and signal power. The findings may incite for future implementation of cooperative deployment program and internet of things (IoT) applications in vehicle-to-infrastructure (V2I) and vehicle-to-vehicle (V2V) communication.
      1  31
  • Publication
    Thermal analysis of LED packaging with single-walled carbon nanotube heat sink
    ( 2023)
    Chu Kok Keong
    ;
    Nor Azura Malini Ahmad Hambali
    ;
    Mohamad Halim Abd. Wahid
    ;
    H. Mohamad
    ;
    Norshamsuri Ali @ Hasim
    The thermal issue is still the bottleneck of a light emitting diode (LED) system to sustain its operational performance. In this paper, we design, simulated, and analysed an LED packaging with single walled carbon nanotubes as a heat sink. The 5W LED packaging is simulated with different types of LED chips materials which comprise gallium nitride, indium nitride, zinc oxide, zinc selenide and titanium dioxide. Using LED chips materials as the heat source, the heat flow is conducted through the bottom layer to the heat sink and dissipates by convection or radiation heat transfer to the surrounding. The addition of thin film on top of the phosphorus layer functions to enhance the recombination rate and guided the flow of heat to the bottom. The 5W titanium dioxide light emitted diode packaging (LED packaging C) has been successfully demonstrated to have overall temperature reduced to around ~10°C by using single walled carbon nanotube heat sink as compared to copper heat sink and aluminium heat sink. Meanwhile, carbon material as thermal interface material and substrate also plays a major role as a thermal cooling solution in LED packaging. For 5W titanium dioxide light emitted diode packaging, under self-heating conditions, the maximum average temperature generated is 81.05 °C. Despite that, under convection conditions, the maximum average temperature generated is 41.53°C.
      9  27
  • Publication
    Generation Orbital Angular Momentum Modes Using Metasurfaces
    ( 2023-10-06)
    NHuda S.
    ;
    Norshamsuri Ali @ Hasim
    ;
    Amphawan A.
    ;
    Nor Roshidah Yusof
    ;
    Rosdisham Endut
    ;
    Nor Azura Malini Ahmad Hambali
    ;
    Mohd Najib Mohd Yasin
    ;
    Syed Alwee Aljunid Syed Junid
    The purpose of this study is to investigate how numerous orbital angular momentum (OAM) modes may be produced by mixing acoustic plane beams with different metasurfaces. This study proposes a novel metasurface that may be simulated in order to generate OAM beams. Multi-beam and multi-mode terahertz wave incidence are produced utilizing vortex modes in the beams. The study of suitable OAM superpositions of waveguide eigenmodes is done using COMSOL Multiphysic, followed by a description of the software's usage and examples of challenges involved. With the existence of these studies, we can also prove that the mode can be produced completely with the results that have been studied. Based on the results obtained, an objective was achieved, which is to design the feature of the vortex beam modes. These results include the construction of a multi-functional vortex beam based on a theoretical model of phase gradient distribution. Also, by using metasurface mimics to specify a periodic structure specified by the user from the built-in unit cell, and the beam was attenuated and split into two paths inside the thin layer. Finally, the simulation process between 2D and 3D is very significant because the mesh and geometry in a design are very different, but generating a beam using COMSOL already has a specific module, namely the wave optic module, which can be used to predict the beam modes.
      1  37
  • Publication
    Smart embedded-analytics sensors with cloud-based measurement system for HVAC
    ( 2020-01-08)
    Aseri N.S.M.
    ;
    Norshamsuri Ali @ Hasim
    ;
    Mohd Najib Mohd Yasin
    ;
    Mohd Rashidi Che Beson
    ;
    Syed Alwee Aljunid Syed Junid
    ;
    Rosdisham Endut
    ;
    Nor Azura Malini Ahmad Hambali
    ;
    Shapiai M.I.
    HVAC system is a necessary component of environment to maintain the temperature and humidity to be kept at certain levels by using air taken from outside to ensure the indoor comfort. The purpose of the study is to reduce the electricity energy usage and cost from air conditioning by using smart embedded-analytics sensors to provide the automatic thermal control in an area. In this study, we used sensors such as temperature and humidity sensors to detect and read the currently temperature and humidity of an area monitored by a microcontroller. The cloud-based system and the sensors are connected via wifi in the presence of MQTT protocol. The protocol enables publish and subscribe method which provide the communication between sensors, cloud-based system and HVAC system. This communication can serve thermal control automatically thus resulting the optimize usage of energy from air conditioning according to the external environment temperature and humidity. The control of the temperature and humidity from air conditioning can be designed through the programming embedded in the microcontroller. The monitoring result can be displayed from the control panel to ensure how the system works.
      31  2
  • Publication
    Multiwavelength fiber laser employing semiconductor optical amplifier in nonlinear optical loop mirror with polarization controller and polarization maintaining fiber
    ( 2020-01-08)
    Husshini N.F.H.
    ;
    Nor Azura Malini Ahmad Hambali
    ;
    Mohamad Halim Abd. Wahid
    ;
    Shahimin M.M.
    ;
    Mohd Najib Mohd Yasin
    ;
    Norshamsuri Ali @ Hasim
    ;
    Al-Asadi H.A.A.
    ;
    Raghavendra C.G.
    This paper demonstrates multiwavelength fiber laser employing semiconductor optical amplifier in nonlinear optical loop mirror with polarization controller and polarization maintaining fiber. The configuration consists of a 3-dB coupler, polarization controller and several lengths of polarization maintaining fiber. The results showed a single polarization controller with 5 meters of polarization maintaining fiber length generated 36 of lasing lines at 160mA of semiconductor optical amplifier current. In addition, for the average peak power and average optical signal to noise ratio, the 2 meters of polarization maintaining fiber length with single polarization controller in the nonlinear optical loop mirror shows higher values, 0.55mW at 210mA and 31.98dB at 210mA, respectively. Both gain media have a wider bandwidth operating in the C-band and L-band at room temperature.
      27  1
  • Publication
    Characteristics of multiwavelength fiber laser employing semiconductor optical amplifier in nonlinear optical loop mirror with different length polarization maintaining fiber
    ( 2020-01-08)
    Husshini N.F.H.
    ;
    Nor Azura Malini Ahmad Hambali
    ;
    Mohamad Halim Abd. Wahid
    ;
    Shahimin M.
    ;
    Mohd Najib Mohd Yasin
    ;
    Norshamsuri Ali @ Hasim
    ;
    Al-Asadi H.A.A.
    In this paper, we propose and demonstrate generated characteristics of a multiwavelength fiber laser based on semiconductor optical amplifier in a nonlinear optical loop mirror with different length of polarization maintaining fiber. The configuration comprises 3-dB optical coupler, semiconductor optical amplifier and, 2 meters and 10 meters of polarization maintaining fiber. Characteristics of multiwavelength fiber laser are studied through the use of polarization maintaining fiber at different lengths. The experimental results revealed the number of lasing lines increases with the increment of the polarization maintaining fiber length. The polarization maintaining fiber with 10 meters of length has the ability to generate a higher number of lasing lines up to 47 signals with semiconductor optical amplifier injected current at 180mA, respectively. However, in terms of average peak power and average optical signal to noise ratio, the 2 meter of polarization maintaining fiber length has the capability to produce a higher value which is 0.45mW at 250mA of semiconductor optical amplifier driven current and 28.86dB at 170mA of semiconductor optical amplifier driven current, respectively. Furthermore, it is observable that this configuration capable to generate a wider bandwidth which is operating in the conventional (C) band to long (L) band at the room temperature.
      37  1
  • Publication
    Tunable transparency and group delay in cavity optomechanical systems with degenerate fermi gas
    (MDPI, 2023)
    Fatin Nadiah Yusoff
    ;
    Muhammad Afiq Zulkifli
    ;
    Norshamsuri Ali @ Hasim
    ;
    Shailendra Kumar Singh
    ;
    Nooraihan Abdullah
    ;
    Nor Azura Malini Ahmad Hambali
    ;
    Collins Okon Edet
    We theoretically investigate the optical response and the propagation of an external probe field in a Fabry–Perot cavity, which consists of a mechanical mode of trapped, ultracold, fermionic atoms inside and simultaneously driven by an optical laser field. We investigate the electromagnetically-induced transparency due to coupling of the optical cavity field with the collective density excitations of the ultracold fermionic atoms via radiation pressure force. Moreover, we discuss the variations in the phase and group delay of the transmitted probe field with respect to effective cavity detuning as well as pumping power. It is observed that the transmitted field is lagging in this fermionic cavity optomechanical system. Our study shall provide a method to control the propagation as well as the speed of the transmitted probe field in this kind of fermionic, ultracold, atom-based, optomechanical cavity system, which might have potential applications in optical communications, signal processing and quantum information processing.
      12  2