Nelidya Md. Yusoff

Universiti Teknologi Malaysia | UTM · Razak Faculty of Technology and Informatics

A tapered microfiber decorated with titanium dioxide-silicon dioxide nanocomposite saturable absorber (TiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> -SiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> -SA) is demonstrated via alkali...

We propose the generation of a multiwavelength spectrum based on Rayleigh backscattering. An erbium-doped fiber amplifier (EDFA) and a Lyot filter act as gain medium and comb filter, respectively. A high number of stable lasing lines is achieved at 51 channels with a 21 dB extinction ratio using 18 dBm of EDFA power. The output multiwavelength spec...

This paper demonstrates a selectable wavelength spacing of thulium-doped fiber laser (TDFL) based on a parallel Lyot filter. An intensity-dependent loss (IDL) mechanism acts as an amplitude equalizer to flatten and stabilize the multiwavelength spectrum. The IDL mechanism is obtained at a specific polarization state from the combination of highly n...

Optical fibers coated with polyaniline (PANI) nanostructures were used to sense ammonia gas (NH3) concentration. The PANI nanostructures were synthesized using the oxidative polymerization process in a solution containing poly(methyl vinyl ether-alt-maleic acid) (PMVEA). The PANI nanostructures were in situ deposited on silica optical fibers by imm...

Energy-saving strategies are required to address the increasing global CO2 and electrical energy consumption problems. Therefore, the determinant factors of electrical energy consumption consist of socio-demographic changes, occupant behavior, house and appliance characteristics, or so-called techno-socioeconomic factors, which all need to be asses...

The dynamic bandwidth allocation (DBA) algorithm is highly impactful in improving the network performance of gigabit passive optical networks (GPON). However, reports delineating its vulnerability to certain attacks can be found in the literature, thus raising concerns. A degradation attack manipulates the transmission control protocol (TCP) conges...

We investigated multiwavelength fiber laser (MWFL) performance using different types of semiconductor optical amplifiers (SOAs) utilizing Lyot filter as comb filter. The lasing performances of linear SOA (LSOA), nonlinear SOA (NLSOA) and booster optical amplifier (BOA) at different current settings were observed. Among the three SOAs, LSOA has the...

We investigate the performance of multiwavelength fiber laser (MWFL) at six simultaneous angle settings of half wave plate (HWP) and quarter wave plate (QWP) using two different types of semiconductor optical amplifiers (SOAs): a booster amplifier and an in-line amplifier. In order to generate multiwavelength, a Lyot filter is inserted into the cav...

A stable dual-wavelength erbium-doped fiber laser is proposed and experimentally demonstrated. The mode competition in the gain medium was suppressed by enhancing the polarization hole burning mechanism through incorporation of polarization maintaining erbium-doped fiber and nonlinear polarization rotation. The fiber laser displayed high stability...

Electricity-saving strategies are an essential solution to overcoming increasing global CO2 emission and electricity consumption problems; therefore, the determinant factors of electricity consumption in households need to be assessed. Most previous studies were conducted in developed countries of subtropical regions that had different household ch...

We investigate the flatness of the output spectrum in two multiwavelength fiber lasers (MWFLs) using two different configurations, unidirectional and bidirectional semiconductor optical amplifiers (SOAs). The most significant finding is the large variance in flatness values between the configurations where the unidirectional SOA is at 6.54 dB and t...

This paper demonstrates a multiwavelength fiber laser (MWFL) using different types of semiconductor optical amplifiers (SOAs) in conjunction with Lyot filter as comb filter. Three different SOAs were compared; linear, non-linear and booster optical amplifier (BOA). The multiwavelength generation using BOA had produced the best performance with exti...

This paper presented an investigation on the effect of hybrid amplifier to multiwavelength fiber laser (MWFL) with in-cavity Lyot filter. The hybrid amplifier comprising semiconductor optical amplifier (SOA) and erbium doped fiber amplifier (EDFA) was used to boost the lasing output peak power. The multiwavelength lasing output has improved by 20 d...

A tunable multiwavelength fiber laser (MWFL) based on bidirectional semiconductor optical amplifier (SOA) in conjunction with a Sagnac loop mirror (SLM) interferometer is proposed. The best multiwavelength spectrum from this setup produces 164 lasing lines within 3 dB uniformity. The main study is to investigate the multiwavelength laser performanc...

We demonstrate a remotely pumped L-band erbium-doped fiber amplifier for long-haul transmission system that consists of a multiwavelength dispersion compensator. In this proposed amplifier, the L-band signals experience double pass amplification using the multiwavelength dispersion compensator as signal reflector. In addition, the distributed Raman...

A literature review is presented specifically on the photovoltaic (PV) as a distributed generation (DG) integration approach and the extensiveness through renewable energy (RE) assessment criteria in current green building rating system (GBRS) to: delineate for further classification in terms of installed-capacity; identify the RE applications' int...

The objective of this paper is to investigate the application of the cross-correlation technique in localizing the leakage in Acrylonitrile Butadiene Styrene (ABS) pipeline using wireless three-axis vibration sensors. Most of the existing leak localization techniques that utilized the cross-correlation method is using acoustic and pressure sensors....

span>This paper shows dual stage thulium-doped fiber amplifiers (TDFAs) that use a pump power distribution technique. Simulations were done with signals ranging from 1975 nm to 2000 nm using the OptiSystem v.13 software. The results required were gathered from the software. The results of gain, noise figure, optical signal-to-noise ratio (OSNR) and...

This paper describes the pattern of electricity consumption from total and selected domestic appliances at a typical terrace house in Malaysia. The measured appliances can be classified into four groups on the basis of pattern of use which are ‘standby’ (TV), ‘active’ (massage chair, charger of hand phone, laptop and power bank, washing machine, ai...

Load profile of household air-conditioning (AC) and total electricity consumption is essential to increase the stability of the energy demand on the grid. Therefore, field measurements on time series data of total and AC electricity consumption from 20 households were conducted from March 2016 to August 2017. The questionnaire survey was carried ou...

We demonstrated a multiwavelength performance based on bidirectional Lyot filter at different temperature of polarization maintaining fiber (PMF) and semiconductor optical amplifiers (SOAs). The multiwavelength fiber laser (MWFL) based on bidirectional Lyot filter is not investigated thoroughly on its channel spacing tunability due to birefringence...

A study about different types of semiconductor optical amplifiers (SOA)s - linear, nonlinear and in-line SOAs modelling is carried out. The SOA key performance characteristics covered in this paper include optical gain, power, and amplified spontaneous emission (ASE) noise figure. These characteristics definition are included in this work together...

Pipeline leakages in water distribution network (WDN) is one of the prominent issues that has gain an interest among researchers in the past few years. Time and accuracy play an important role in leak localization as it has huge impact to the human population and economic point of view. The complexity of WDN has prompt numerous techniques and metho...

We demonstrate a broad bandwidth multiwavelength laser based on a bidirectional Lyot filter and a semiconductor optical amplifier with a mechanism of intensity-dependent loss as the flatness agent. A wide bandwidth of a multiwavelength spectrum of 32.9 nm within a 5 dB uniformity is obtained under optimized polarization parameters. For this case, t...

We experimentally demonstrate a multiwavelength fiber laser (MWFL) based on bidirectional Lyot filter. A semiconductor optical amplifier (SOA) is used as the gain medium, while its combination with polarization controllers (PCs) and polarization beam combiner (PBC) induces intensity dependent loss (IDL) mechanism. The IDL mechanism acts as an inten...

The residential sector was one of the contributors to the increase in the world energy consumption and CO2 emission due to the increase population, economic development, and improved living standard. Developing a reliable model of electrical energy consumption based on techno-socio economic factors was challenging since many assumptions need to be...

We have demonstrated the performance improvement of L-band hybrid remote Erbium-doped fiber amplifier by introducing a phase modulator to suppress the stimulated Brilloiun scattering (SBS) effect in the transmission. The transmission gain has improved by 12.65 dB while the noise figure has reduced by 47.1 dB when 0 dBm signal power is generated at...

The aim of this study was to conduct short-term measurements on household electricity demand under hot weather conditions in a residential area in Kuala Lumpur. The measurements included total and air conditioner (AC) electricity consumption of 10 households in an apartment building as well as outdoor air temperatures, which were collected from Mar...

We demonstrate two pumping scheme for thulium-doped fiber amplifier (TDFA) by using OptiSys v. 13 that is spanning from 1770 nm to 1970 nm; providing all the results represented in the figures. Higher gain is achieved in the single stage TDFA however high output power is achieved in the distributed pumping TDFA. The reduction of noise figure by alm...

A Q-switched Thulium-doped Fiber Laser (TDFL) operating at approximately 2 µm wavelength is successfully generated by using four different saturable absorbers (SAs) which are nitrogen-doped graphene in PVA (NG:PVA), nitrogen-doped graphene in PEO (NG:PEO), single-walled carbon nanotube in PVA (SWCNT:PVA), and high pressure carbon monoxide carbon na...

Q-switched Thulium-doped fiber laser has been demonstrated with two configurations; linear cavity and ring cavity. Nitrogen-doped graphene in polyvynil alcohol has been applied in both laser cavities during loss modulation process.

The placement of Chirped Fiber Bragg grating in between the span plays an important role as it affects the signal quality when it reaches the transmission end. The work highlights on the signal performance at 10 Gbps data rate after propagating through a 90 km transmission fiber. The worst BER is obtained in the inline compensation configuration as...

We have demonstrated multiwavelength fiber laser (MWFL) based on bidirectional Lyot filter and semiconductor optical amplifier (SOA). The intensity dependent loss (IDL) mechanism is utilized to obtain a flat multiwavelength spectrum of 94 wavelength lines within 5 dB bandwidth. The extinction ratio (ER) is 9 dB, while the line spacing is narrow at...

The work investigated the Q-switched Thulium-Doped Fiber Laser (TDFL) that operates in 1900 nm region by using nitrogen graphene (NG) embedded in polyethylene oxide (PEO) as saturable absorber (SA). The highest output power achieved was 0.52 mW with highest repetition rate of 33.43 kHz. The shortest pulse width was 3.205 μs with pulse energy of 31....

Bidirectional pumped dual-stage L-band EDFA utilizing a single power splitter and pump laser has been presented in this paper. A power splitter has been used to distribute the pump power bidirectionally to pump two EDFs with different length. An average gain of 18.6 dB with average NF of 8.6 dB has been attained when the signal is equal to 0 dBm ra...

We investigate a flat multiwavelength fiber laser (MWFL) with the extinction ratio (ER) is continuously adjustable at variation of either half wave plate (HWP) position or polarization maintaining fiber (PMF) length. The multiwavelength laser is generated from an intensity dependent transmission (IDT) effect which is induced from nonlinear polariza...

A downlink remote optical local oscillator for radio over fiber (RoF-ROLO) system was successfully demonstrated experimentally at up-conversion frequency of 12.92 GHz. Up-conversion architecture was employed at the base station (BS) while the optical signal was generated at the central station (CS) using stimulated Brillouin scattering (SBS) techni...

A dual-stage erbium doped fiber amplifier (EDFA) having a flat gain wavelength response throughout L-band transmission window is presented. By applying pump power distribution technique, the pump power is distributed to two different stages with different length of EDF depending on the coupling ratio. By controlling these two parameters, gain of 19...

Erbium-doped fiber amplifier with flat gain over 30 nm bandwidth is demonstrated using flexible selective band methods. The band optical amplifier was designed to cater 44 wavelength division multiplexing channels which were separated into bands of 4 nm. Without using any gain flattening filter, the gain of optical amplifier was maintained at 19 dB...

A dual-stage L-band erbium-doped fiber amplifier with a flat gain bandwidth over 36 nm is demonstrated using pump distribution technique. The pump power was distributed to two stages depending on the splitting ratio and the length of erbium-doped fiber that was used for this configuration. Both parameters are the key components for achieving a subs...

We demonstrated a tunable S-band multiwavelength fiber laser based on semiconductor optical amplifier (SOA) and hybrid amplifier. The proposed multiwavelength utilizes a comb filter based on one PMF segment of Lyot birefringence filter for multiwavelength tunability. The wavelength spacing and the peak flatness can be altered by adjusting polarizat...

The effect of stimulated Raman scattering (SRS) in remote pumping scheme for L-band erbium-doped fiber amplifier (EDFA) was studied in this experiment. Observation was done on the gain and noise figure performance as well as the Raman distributed gains of the remotely-pumped L-band erbium-doped fiber amplifier with the existence of SRS. The utiliza...

Gain and noise figure improvements are demonstrated in a shorter wavelength region of a double-pass EDFA using a macrobending approach. The EDF is wound in a small radius to suppress the amplified spontaneous emission at the longer wavelength in order to achieve a high amplification in the shorter wavelength. Gain enhancements of about 12–14 dB are...