Research Output
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PublicationEnhancement receiver sensitivity under heavy attenuation effect for FSO system via double transmission technique( 2024-02-08)This paper focus on improvement of receiver sensitivity for free space optical communication. FSO communication is frequently drop performance when facing bad weather. In this research proposed new development of transmitter and receiver design in order to reduce the impact of atmospheric attenuation and increase receiver sensitivity. The analysis performance will compare with conventional amplitude shift keying (ASK) approach. Simulation result will be used to measure the performance and comparison between conventional and new proposed modulation double transmission balance receiver (DTBR) will also presented. The measurement of result will involve the effect of geometrical loss, data bit rate and distance propagation. From the result, the DTBR is increase the receiver sensitivity in term of bit error rate (BER) performance.
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PublicationPerformance Enhancement of SAC-OCDMA System Using an Identity Row Shifting Matrix Code( 2022-01-01)In order to face the shortcomings and problems, in spectral amplitude coding-optical code-division multiple access (SAC-OCDMA) systems, presented by multiple access interference (MAI) and its accompaniment phase-induced intensity noise (PIIN), limited capacity, etc., that prevent them to function effectively as well make performances poor. For these reasons, this paper offers a solution by proposing a novel encoding technique namely identity row shift matrix (IRSM) code based on an identity matrix and shifting property with target of beating the challenges aforementioned. Our proposed code is featured by zero cross-correlation (ZCC) property restricting the MAI effect as well neglecting PIIN which in turn positively reflects on system performance. Mathematical results appear the ability of IRSM code to improve the performance of SAC-OCDMA system as well outperform reported codes such as: diagonal permutation shift, (DPS), modified double weight (MDW), and random diagonal (RD) codes. For example, in term of system capacity, it amounts to 25, 48, 58, and 88, respectively, based on DPS, MDW, RD, and IRSM codes referring a remarkable enhancement. Additionally, mimic result demonstrates that IRSM code is suitable for attaining optical communication requirements through producing BER and Q-factor reach 10- 14 (≤ 10- 9 ) and 7.59 dB (≥ 6 dB ), consecutively.
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PublicationTemperature monitoring system using fiber Bragg grating (FBG) approach( 2020-01-08)In this paper, a temperature monitoring system is proposed by using fiber Bragg Grating (FBG) approach. This system can be done by using OptiSystem simulation and hardware implementation. FBG was employed as it allows a reflected wavelength of light that shifts in response to variations in temperature and/or strain. Generally, FBG sensors offer ease of installation, higher accuracy, longer stability, smaller size, immunity to electromagnetic interference (EMI) and the ability to measure ultra-high and speed events. The results indicated that wavelength shifting is depended on thermal expansion coefficient of materials, which are 0.55e-6 for default and 24e-6 for aluminium. Aluminum has a better sense rather than the default one in this study. For hardware implementation, it is shown that the power level is increased from one value to another progressively.
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PublicationModulation index and phase imbalance of dual-sideband optical carrier suppression (DSB-OCS) in optical Millimeter-wave system( 2021-01-01)This paper presents a Dual-sideband Optical Carrier Suppression (DSB-OCS) technique which is used to generate an optical millimeter-wave (mm-wave) signal in radio over fiber (RoF) systems. The proposed system employs a Dual-Electrode Mach-Zehnder Modulator (DE-MZM) and a carrier of 40 GHz mm-wave for data transmission through the RoF systems. Characteristics determining the performance of the system, among which are the modulation index, phase imbalance and dispersion parameters, are included. The performance evaluations of the system show that the mm-wave signal output power follows MZM’s transfer function when the modulation index is raised. Moreover, the generated optical mm-wave signal power is affected by phase imbalance and optical splitting ratio. It is observed that the optical fiber dispersion influences the DSB-OCS system by decreasing the amplitude of the mm-wave and the signal-to-noise ratio (SNR).
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PublicationHybrid Dy-NFIS & RLS equalization for ZCC code in optical-CDMA over multi-mode optical fiber( 2021-01-01)For long haul coherent optical fiber communication systems, it is significant to precisely monitor the quality of transmission links and optical signals. The channel capacity beyond Shannon limit of Single-mode optical fiber (SMOF) is achieved with the help of Multi-mode optical fiber (MMOF), where the signal is multiplexed in different spatial modes. To increase single-mode transmission capacity and to avoid a foreseen “capacity crunch”, researchers have been motivated to employ MMOF as an alternative. Furthermore, different multiplexing techniques could be applied in MMOF to improve the communication system. One of these techniques is the Optical Code Division Multiple Access (Optical-CDMA), which simplifies and decentralizes network controls to improve spectral efficiency and information security increasing flexibility in bandwidth granularity. This technique also allows synchronous and simultaneous transmission medium to be shared by many users. However, during the propagation of the data over the MMOF based on Optical-CDMA, an inevitable encountered issue is pulse dispersion, nonlinearity and MAI due to mode coupling. Moreover, pulse dispersion, nonlinearity and MAI are significant aspects for the evaluation of the performance of high-speed MMOF communication systems based on Optical-CDMA. This work suggests a hybrid algorithm based on nonlinear algorithm (Dynamic evolving neural fuzzy inference (Dy-NFIS)) and linear algorithm (Recursive least squares (RLS)) equalization for ZCC code in Optical-CDMA over MMOF. Root mean squared error (RMSE), mean squared error (MSE) and Structural Similarity index (SSIM) are used to measure performance results.
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PublicationEffect of phase imbalance on the mm-wave signal in the DWDM-RoF system( 2022-01-01)Dense wavelength division multiplexing (DWDM) and radio over fiber (RoF) are promising technologies that are able to provide unlimited transmission capacity, which meets the growing demands of bandwidth in communication systems. In this paper, an architecture for DWDM-RoF access networks uses a single Mach Zehnder modulator (MZM) to generate the mm-wave signal. This paper aims to study the effect of phase imbalance on the mm-wave signal to reduce the insertion loss in the system. It is found that the phase imbalance affects the insertion loss. The phase imbalance can be controlled by adjusting the injected phase, and the best result is collected at π 3 and 5π 12 phases.
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PublicationMedical healthcare M2M system using the VLC system( 2020-01-08)The RF communication has suffered from the interference and excessive latency issues. It is required a separated setup for transmission and reception of RF waves. To overcome this problem, the VLC system is a chosen technique due to high bandwidth and immunity to interference from electromagnetic sources. In this project, Optisystem Software version 15 has been chosen to study the perfomances of the VLC system in directed LOS. The performance results will be displayed on BER analyser and the simulation that has been done is iterating continuously in order to get the acceptable results. The result indicates that the reading of simulation of 1 user for both bit rate 155Mbps and 622Mbps shows the best result compared to 4 users. Without using any kind of OCDMA system, the number of users will reach the limitations which is not more than 4 users. The number of users influences the performance of the system and the result shows the decrement of BER reading which is lower than 10-9.
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PublicationDesign and Implementation of FPGA-based Single Computing Engine of VLC Image Transfer( 2023-10-06)This paper has proposed a single computing engine based on VLC technology for use in real-time to secured image of transmitter and receiver systems implemented on an FPGA in real time. It is proposed that a single computing engine system consist of the following components be implemented: UART control, FIFO buffer, VGA controller, and 128-bits AES algorithm decryption and encryption. An Altera DE1-SoC board is used to implement the design, coded in VHDL, and implemented in Quartz prime 15.1 FPGA using a software platform system architecture. The single computing engine communication via VLC system hardware provides the highest security benefit with excellent image quality and unnoticeable local area communication security features. It has been demonstrated through implementation results that the single computing engine can operate at a maximum clock frequency of Fmax 170.97 MHz and achieve a throughput of 1.367 Mbps with the design single computing engine.
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PublicationComparison study of 8-PPM, 8-DPIM, AND 8-RDH-PIM modulator FPGA hardware design in term of bandwidth efficiency and transmission rate( 2020-04-01)In this paper, a performance study of 8-Pulse-Position Modulation (PPM), 8-Digital Pulse Interval Modulation (DPIM), and 8-Reverse Dual Header-Pulse Interval Modulation (RDH-PIM) implementation in Verilog hardware design language is presented. The hardware design is chosen over software design since it could provide much more flexibility in term of transmission rate and reduce the workload of the processor in the complete system. Using 50 MHz clock as the reference data clock speeds, the transmission rate recorded are 11.11 Msymbol/second or 33.33 Mbps, 9.09 Msymbol/s or 27.27 Mbps, and 6.25 Msymbol/s or 18.75 Mbps for 8-RDH-PIM, 8-DPIM, and 8-PPM respectively. We conclude that 8-RDH-PIM modulator design provides better performance in term of bandwidth utilization and transmission rate as compared to 8-PPM and 8-DPIM.
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PublicationEnhancing Cardiac Arrhythmia Detection in WBAN Sensors Through Supervised Machine Learning and Data Dimensionality Reduction Techniques( 2023-12-01)In recent years, the global medical community has endeavored to provide swift and efficient patient care by leveraging real-time patient databases. However, the efficacy of these systems, particularly wireless body area network (WBAN) sensors, has been undermined by inaccurate and low-performance readings, leading to unnecessary alarm triggers. This study scrutinizes the potential of data dimensionality reduction techniques and machine learning algorithms in augmenting the detection accuracy of cardiac abnormalities in WBAN sensors. Dimensionality reduction was performed using principal component analysis (PCA), independent component analysis (ICA), and spatial correlation methods. For arrhythmia prediction, Decision Tree and Multilayer Perceptron algorithms were implemented and their performance compared. Numerical simulations and Python code analysis revealed that the application of data reduction techniques significantly improved the reliability and effectiveness of WBAN sensors in handling voluminous datasets. Furthermore, the use of PCA, ICA, and spatial correlation strategies notably reduced WBAN sensor battery energy consumption, data storage needs, computational complexity, and processing time. These pragmatic solutions could potentially empower healthcare practitioners to intervene proactively before patients encounter life-threatening conditions. The results also demonstrated that feature selection effectively eliminated irrelevant attributes from noisy Electrocardiograms (ECGs), thereby enhancing the precision of the analyses.
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