Siti Julia Rosli
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Preferred name
Siti Julia Rosli
Official Name
Siti Julia, Rosli
Alternative Name
Rosli, S.J.
Main Affiliation
Scopus Author ID
16053179200
Researcher ID
GTM-8357-2022

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Hybridization of modified sine Cosine and Cuckoo search algorithms for binary sequences in radar communication system

2021 , Siti Julia Rosli

Finding binary sequences with high Merit Factor (MF) is a main problem in Low Autocorrelation Binary Sequences (LABS) for range compression radar to provide information concerning the target's location, motion, size and other parameters. MF is a measure of the quality of the sequence with low Energy level (E) and flexible length of binary sequences. The largest binary sequence of high MF is known as a supply for a good initial bound for exact search methods. This study attempted to solve the constraints of Sine Cosine Algorithm (SCA) that may have redundancy values of search agent and tendency to trap in local optima for LABS in achieving high MF. The main contribution of this work is the Hybridization of Modified Sine Cosine and Cuckoo Search Algorithms (HMSCACSA) to develop an improved identification capability compared to the conventional SCA. Second contribution is the HMSCACSA featuring the Inverse Filtering (IF) for LABS. In this case, SCA was modified using Latin Hypercube Sampling (LHS) to identify SCA random solution. Therefore, Modified SCA (MSCA) serves to guide SCA in obtaining a better local optimum in the exploitation phase with a fast convergence achievement through an optimum value of the solution. HMSCACSA lead to an excellent combination to determine the ideal nest location and a new position to achieve better results in the search process. The HMSCACSA optimizer was tested over fourteen (14) benchmark experimental functions within a classical category of 24 significant benchmark issues, a current variety of benchmark issues IEEE CEC 2017. The effectiveness of HMSCACSA was validated in terms of performance and statistical analysis, which included hybrid-to-hybrid metaheuristic, Particle Swarm Optimization- Grey Wolf Optimizer (PSOGWO), particle swarm optimization-artificial bee colony (PSOABC), and particle swarm optimization-gravitational search algorithm (PSOGSA) to ensure that the comparison between the metaheuristics was fair. Compared to other hybrid metaheuristics, the majority of the used benchmark mathematical functions indicated that the simulation of the HMSCACSA achieved faster convergence curves by 63.89%. In LABS, HMSCACSA using IF method was proposed to achieve better results with two large MF is 12.12 (LABS-IF) and 12.6678 (HMSCACSA-IF) were obtained for both lengths 231 and 237 where both of the optimal solutions belong to the skewsymmetric sequences. Now, the MF was outperformed up to 24.335% and 2.708% against the state-of-the art benchmark algorithms, xLastovka and Golay. These results indicated that the simulation of the proposed algorithm had quality solutions in a fast convergence curve, better optimal means and standard deviation. The HMSCACSA-IF has a potential to increase the target detection capability with low energy and good range resolution that has low autocorrelation function in LABS.

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Side lobe suppression of Vivaldi antenna using shorting pin structure

2017-01-03 , Wee Fwen Hoon , Yew Been Seok , Siti Julia Rosli , Siti Nur Ainni Dzaaba , Lee Yeng Seng

This paper was executed in order to design side lobe suppression of Vivaldi antenna using shorting pin structure at S-band frequency. Nowadays, Vivaldi antenna has been used to satellite communications, remote sensing and radio telescope. There are a variety of designs such as tapered slot Vivaldi antenna, antipodal Vivaldi antenna and balanced antipodal Vivaldi antenna. Tapered slot Vivaldi antenna has been selected to design the project. The design of the antenna is start with patch antenna by using basis of transmission line model (TLM) formula to calculate the length and width of the patch. It is shaped into Vivaldi antenna. For the final design, the shorting pin structure will connect the patch on top side and the ground plane to absorb the unbalanced current. The shorting pin will reduce the side lobe. The antenna was simulated by using CST Microwave Studio. Based on the simulation results, the Vivaldi antenna shows a good performance as the return loss less than - 10 dB, voltage standing wave ratio, gain, directivity and radiation pattern was obtained the desired result as for a resonant frequency of 3 GHz. The radiation pattern of Vivaldi antenna with shorting pin structure reducing as compared with the design without shorting pin structure. The final antenna design shows that it has a few main lobe magnitudes where the antenna can focus and direct the energy for transmission or receiving of the energy signal.

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Synthesis of multilevel and binary sequences with good correlation properties

2013 , Siti Julia Rosli

In radar systems the very low side lobes that can be achieved with amplitude and phase modulated pulse trains especially particularly in systems requiring a large dynamic range. Moreover, the excellent self-clutter rejection performance is obtained without sacrificing the ability for the separation of close targets (no main lobe widening). The additional expense of encoding and decoding in amplitude and phase may be justified for radars that must cope with land clutter or operating in a dense-target environment. To choose a suitable transmit waveform is an important problem in radar design. This is so because, the waveform controls resolution, clutter performance and also bears heavily on the system cost. Theoretical studies which provide the basis for technical advances have not so far solved the general signal design problem. The knowledge about the properties of the pulse trains shows that, a class of signals particularly well suited to digital processing of increasing practical importance. Two properties of such sequences are of interest. One is the energy ratio (ER) defined as the ratio of the total energy of the sequence to the energy of the largest pulse. The other property is the total side lobe energy (SLE) which is the energy in the side lobes of the autocorrelation function of the sequency. The work presented in this research is mainly concerned with the synthesis of multilevel and binary waveform of any desired length that has high energy ratio and low side lobe in their autocorrelation function (ACF). For the design of multilevel sequences in iterative technique is proposed, this techniques employed the properties of optimum inverse filtering and shown to be effective for the generation of multilevel sequences in any desired lengths. The method of clipping proposed in this research converts a multilevel sequence to binary sequence in same lengths while it is still retaining at low side lobe in autocorrelation function. It is shown that the iterative method based on inverse filtering and the method of clipping provide effective techniques for the generation of multilevel sequences that have high energy ratio and low side lobe energy in their autocorrelation function. Such sequences can then be effectively used to improve the range and Doppler resolution of radars.

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Design of A 20-Bit Chipless RFID Tag Utilizing Multiple Resonators in UWB Frequency Range

2023-01-01 , Radhakrishna K. , Khairul Najmy Abdul Rani , Wahab A.A. , Siti Julia Rosli , Hasliza A Rahim @ Samsuddin , Seng L.Y. , Omar M.H. , Khairul Affendi Rosli

Radio frequency identification (RFID) is a growing technology for monitoring and recognizing objects, persons, or animals via wireless communications. Precisely, RFID can operate longer range and has an ability to be automated without human control. Chipless RFID tag basically is a RFID tag that does not require a microchip in the transponder. The major impediments in designing chipless RFID tag are data encoding and transmission. The passive chipless RFID tag can be fabricated on any substrate material without external operating circuit, which is different compared to a conventional chipped RFID tag. In this paper, 20 resonators are used to design a 20-bit chipless RFID tag, which operates at the ultra-wideband (UWB) frequency range between 3.00 and 10.00 GHz. It is found that the additional resonators can encode data and increase the chipless RFID tag's encoding capacity significantly. In sum, multiple resonators enable the chipless RFID tag to encode data at different operating frequencies.

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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.

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A Review on Research Trends in using Cuckoo Search Algorithm: Applications and Open Research Challenges

2023-01-01 , Safdar K. , Khairul Najmy Abdul Rani , Hasliza A Rahim @ Samsuddin , Siti Julia Rosli , Mohd Aminudin Jamlos

This paper provides an exclusive understanding of the Cuckoo Search Algorithm (CSA) using a comprehensive review for various optimization problems. CSA is a swarm-based nature inspired, intelligent and metaheuristic approach, which is used to solve complex, single or multi objective optimization problems to provide better solutions with maximum or minimum parameters. It was developed in 2009 by Yang and Deb to emulate the breeding behaviour of cuckoos. Since CSA provides promising solutions to solve real world optimization problems, in recent years there have been introduced several new modified and hybridized CSAs using for different applications. In this regard this article provides a comprehensive survey including recent trends, modifications, open research challenges, applications, and related taxonomies for various optimization problems. The literature of this reviewed paper belongs to the domains of engineering, optimization, and pattern recognition. The aim of this review paper is to provide a detailed overview regarding CSA for possible future directions using the recent contributions.

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