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All Journal TELKOMNIKA (Telecommunication Computing Electronics and Control) Bulletin of Electrical Engineering and Informatics Indonesian Journal of Electrical Engineering and Computer Science
Ahmed Nabih Zaki Rashed
Menoufia University
Computer Science & IT Electrical & Electronics Engineering

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Raised cosine/NRZ line coding techniques for upgrading free space optical communication systems through various levels of fog Aadel M. Alatwi; Ahmed Nabih Zaki Rashed
TELKOMNIKA (Telecommunication Computing Electronics and Control) Vol 18, No 6: December 2020
Publisher : Universitas Ahmad Dahlan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12928/telkomnika.v18i6.16236

Abstract

This study examines raised cosine/NRZ line coding techniques for upgrading free space optical (FSO) communication systems through various levels of fog.The max. Q factors are simulated and estimated for clear air, light fog, and moderate fog weather conditions at a data rate of 20 Gb/s. The optical signal to noise ratio is also measured for different weather conditions. The total power after both FSO channel and avalanche photodiode (APD) photo-detector receiver is estimated by an optical power meter for max. distances.The study shows that the max. propagation distance is extended to 50 kmthrough clear air, 2.25 km through light fog, and 1.6 km through moderate fog with acceptable max. Q factor
High speed modulated wavelength division optical fiber transmission systems performance signature Aadel M. Alatwi; Ahmed Nabih Zaki Rashed; Ismail A. Abd El Aziz
TELKOMNIKA (Telecommunication Computing Electronics and Control) Vol 19, No 2: April 2021
Publisher : Universitas Ahmad Dahlan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12928/telkomnika.v19i2.16871

Abstract

This study presents modulated-wavelength division radio signals over fiber with mixed modulation techniques in the transmitter stage. Hybrid optical sources are used to achieve optimal performance and enhancement for an optical fiber communication network. The proposed modulation techniques work at a frequency of 250 GHz. Optical quadrature phase shift keying (OQPSK) and phase modulation (PM) techniques were merged to create OQPSKPM. This was in addition to the minimum shift keying (MSK) modulation scheme that was applied in the proposed model. The modulated wavelength division multiplexing design to four subscribers was examined with a single mode optical fiber at a 1550 nm wavelength. The proposed and previous simulation models were executed, investigated and measured on important operating parameter quantities that expressed the behavior of the optical fiber network in detail, like maximum quality factor, minimum bit error rate, and output power. The obtained simulation results demonstrated the priority of the proposed simulation model.
Advanced modulation coding schemes for an optical transceiver systems–based OWC communication channel model Hazem M. El-Hageen; Aadel M. Alatwi; Ahmed Nabih Zaki Rashed
Bulletin of Electrical Engineering and Informatics Vol 10, No 2: April 2021
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.11591/eei.v10i2.2433

Abstract

This paper examines advanced modulation coding schemes for an optical transceiver systems–based optical wireless communication (OWC) channel model. These modulation techniquesinclude On-Off keying and return to zero (RZ)/non–return to zero (NRZ) coding. The signal power level against time and frequency spectral variations are measured. The max. Q factor and min. bit error rate (BER) are estimated and clarified for each modulation code scheme by using an optisystem simulation model. Transmission bit rates of up to 40 Gb/s can be achieved for possible distances up to 500 km with acceptable Q factor. The received power and max. Q factor are measured and clarified with OWC distance variations. The On-Off keying modulation code scheme resulted in better performance than the other modulation code schemes did.
First order surface grating fiber coupler under the period chirp and apodization functions variations effects Alsharef Mohammad; Mohammed S. Alzaidi; Mahmoud M. A. Eid; Vishal Sorathiya; Sunil Lavadiya; Shobhit K. Patel; Ahmed Nabih Zaki Rashed
Indonesian Journal of Electrical Engineering and Computer Science Vol 25, No 2: February 2022
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.11591/ijeecs.v25.i2.pp1020-1029

Abstract

The paper has demonstrated the first order surface grating fiber coupler under the period chirp and apodization functions variations effects. The Fiber coupler transmittivity/reflectivity, the fiber coupler grating index change and the fiber coupler mesh transmission cross-section are clarified against the grating length with the quadratic/cubic root period chirp and Gaussian/uniform apodization functions. The fiber coupler delay and dispersion are simulated and demonstrated with grating wavelength with quadratic/cubic root period chirp and Gaussian/uniform apodization function. As well as the fiber coupler output pulse intensity is simulated against the time period with the quadratic/cubic root period chirp and Gaussian/uniform apodization function. The fiber coupler peak intensity variations against the transmission range variations is also demonstrated by OptiGrating simulation software.
Free space optical communication system for indoor applications based on printed circuit board design Alsharef Mohammad; Mohammed S. Alzaidi; Mahmoud M. A. Eid; Vishal Sorathiya; Sunil Lavadiya; Shobhit K. Patel; Ahmed Nabih Zaki Rashed
Indonesian Journal of Electrical Engineering and Computer Science Vol 25, No 2: February 2022
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.11591/ijeecs.v25.i2.pp1030-1037

Abstract

This study clarified an overview of wired and wireless optical communication system block diagram with practical applications. Freespace optical (FSO) communication is a trending field that is rising so fast to replace electromagnetic waves in a communication, so we have presented a theoretical circuit as an example and modified it to fit and work in communication purposes, simulation is used and then practical work is done and printed circuit board (PCB) is designed. Light emitting diode (LED) have been used as transmitter and Photo Transistor as a receiver and variable resistance to change voltage sent to the LED that indicates the change in the transmitted signal.
A pulse amplitude modulation scheme based on in-line semiconductor optical amplifiers (SOAs) for optical soliton systems Aadel M. Alatwi; Ahmed Nabih Zaki Rashed
Indonesian Journal of Electrical Engineering and Computer Science Vol 21, No 2: February 2021
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.11591/ijeecs.v21.i2.pp1014-1021

Abstract

The objective of this work is to simulate a pulse amplitude modulation (PAM) scheme based on in-line semiconductor optical amplifiers for optical soliton systems. The max. power for soliton systems, based on various bits/symbol PAM modulation schemes after a fiber length of 100 km, is simulated and clarified. In addition to the max. Q factor for soliton systems, PAM modulation schemes with various in-line SOA injection currents and a fiber length of 100 km are also simulated and demonstrated in the results. The total electrical power after photo-detectors for soliton systems, based on PAM modulation schemes with various in-line SOA injection currents and a fiber length of 100 km, is also simulated and clarified in the results. The study emphasizes that the higher the SOA injection current, the higher the electrical power and the lower the Q factor that can be achieved in the soliton system.
Conventional doped silica/fluoride glass fibers for low loss and minimum dispersion effects Aadel M. Alatwi; Ahmed Nabih Zaki Rashed
Indonesian Journal of Electrical Engineering and Computer Science Vol 21, No 1: January 2021
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.11591/ijeecs.v21.i1.pp287-295

Abstract

This paper has clarified the conventional silica doped (SiGeO2) and aluminum fluoride (AlF3) fibers for low loss and minimum dispersion effects for upgrading fiber-optic communication systems. The total dispersion with the total losses are modeled for both fibers. Fiber bandwidth and the power received are estimated based on different dopant ratios. The spectral and thermal effects are applied on both fibers. The study assured the negative effects of increasing ambient temperatures and the positive effects of increasing dopant ratios on the performance of the fibers. 
Numerical investigation of V shaped three elements resonator for optical closed loop system Iraj Sadegh Amiri; Ahmed Nabih Zaki Rashed
Indonesian Journal of Electrical Engineering and Computer Science Vol 16, No 3: December 2019
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.11591/ijeecs.v16.i3.pp1392-1397

Abstract

This study have outlined numerical investigation of V shaped three element resonator. The stability parameter is measured against back mirror curvature radius, back mirror phase angle, focusing length, focusing mirror phase angle, folding range in both S plane and T plane. The stability parameter is changed in positive and negative trend under the operating system parameters. The stability parameter should be optimized in order to achieve high performance efficiency of resonator system. Beam radius variations are also measured versus focusing range, folding range, and back mirror phase angle. It is clear that the negative effects of increasing system parameters on beam radius variation in both S plane and T plane. 
Influence of device to device interconnection elements on the system behavior and stability Iraj Sadegh Amiri; Ahmed Nabih Zaki Rashed; Preecha Yupapin
Indonesian Journal of Electrical Engineering and Computer Science Vol 18, No 2: May 2020
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.11591/ijeecs.v18.i2.pp843-847

Abstract

This work has presented the interaction between tangential/sagittal cylindrical thin lens in the titled plane parallel crystal. Stability criterion parameters are measured under the control of curvature radius of a spherical mirror, the thickness of the tilted plane crystal, the refractive index of tilted plane crystal, the thickness for a plate of matter and phase angle of the sagittal cylindrical thin lens. Beam radius waist is plotted against the focal length of the tangential cylindrical thin lens. Focal length for both thin lens in resonator crystal is optimized to upgrade the resonator system operation efficiency.
High modulated soliton power propagation interaction with optical fiber and optical wireless communication channels Mahmoud M. A. Eid; Ashraf S. Seliem; Ahmed Nabih Zaki Rashed; Abd El-Naser A. Mohammed; Mohamed Yassin Ali; Shaimaa S. Abaza
Indonesian Journal of Electrical Engineering and Computer Science Vol 21, No 3: March 2021
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.11591/ijeecs.v21.i3.pp1575-1583

Abstract

This paper has presented high modulated soliton power transmission interaction with optical fiber and optical wireless communication channels at flow rate of 40 Gbps and 20 km link range. The proposed modulation schemes are continuous phase frequency shift keying (CPFSK), Quadrature amplitude modulation (QAM), differential phase shift keying (DPSK), frequency shift keying (FSK), pulse amplitude modulation (PAM), minimum shift keying (MSK), and optical quadrature phase shift keying (OQPSK). CPFSK has presented better performance than other proposed modulation schemes for both optical fiber and optical wireless communication channels. The enhancement of optical signal/noise ratio at fiber/wireless channel, received electrical power and signal/noise ratio at optical receiver with increase of bits per symbol for different proposed modulation schemes except for CPFSK scheme. Therefore it is evident that CPFSK modulation scheme is more efficient and better performance than other modulation schemes for different communication channels. The obtained results are simulated with optisystem program version 13.
Co-Authors Aadel M. Alatwi Aadel M. Alatwi Aadel M. Alatwi Abd El-Naser A. Mohammed Abd El-Naser A. Mohammed Ahmed M. El-Eraki Alsharef Mohammad Ashraf S. Seliem Hazem M. El-Hageen Iraj Sadegh Amiri Ismail A. Abd El Aziz Mahmoud M. A. Eid Mohamed Yassin Ali Mohammed S. Alzaidi Norah Muhammad Alwadai Preecha Yupapin Shabana Urooj Shaimaa S. Abaza Shobhit K. Patel Sunil Lavadiya Vishal Sorathiya