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The Linear and nonlinear effects in optical fibers are very important and influential factors that effect on the power of the signal transmitted within the optical fiber. In this paper, the mathematical model for these effects was presented. The most important methods used to compensate these losses were also reviewed. The compensation methods reviewed include various linear and nonlinear effects most of the methods reviewed focused on increasing the length of the optical fiber to transmit the signal with the least consumed power and high data transfer rate at low design cost

— A novel single-step, low-complexity Artificial Intelligence (AI) algorithms proposed by using a Deep Neural Network (DNN) technique based a nonlinear compensation (NLC) to determine and resolve the fiber nonlinearity impairments for Coherent-OpticOrthogonal-Frequency-Division-Multiplexing (CO-OFDM) with 8 channels WDM, it done by learning the network from the receiving information itself as a new alternative framework for future optical communications. The results will be comparing with the recent NLC technique such as Volterra-Series Transfer Function (VSTF) and electronic non-linearity compensation schemes. The proposed scheme is verified by the OptiSystem simulations app. with transmission link up to 3000 km @ 60 Gbps bit rate/ch., Quadrature Amplitude Modulation (QAM)-Single Polarization-CO-OFDM. The obtained results showed that: The proposed DNN has scalability to higher-order QAM modulations with achieving greater gain in nonlinear impairments compensation compare to classical NLC techniques based on Digital Back Propagation (DBP) and its successfully demonstrated to modify the QAM constellation and a Qfactor improvement 2 dB with respect to the Artificial Neural Network (ANN-NLC) and 4 dB to the VSTF-NLE. Its performance is evaluated experimentally on coherent 262144-bit sequence length back-to-back measurements by pre-distort symbols at transmitter side to exhibit Q factor improvements. The DNN's weights are constructed from training data with intrachannel cross-phase modulation (XPM) and self-phase modulation (SPM) that used as input features. Knowing that, the essential goal for DNNs is to compensation nonlinearity impairments which effect on optical data transmission in terms of Quality factor (Q), Bit Error Rate (BER) and Eye-Opening Factor (EOF). So, more importantly channel. distortion and noises are effectively compensated.by DNNs .

The optical frequency comb generator (OFCG) is an efficient optoelectronic device that is included in many important applications over a various field such as microwave and optical communication. A novel scheme of OFCG presented in this work for visible light communication application based on amplitude modulation, radio frequency (RF) signal, phase shift and two Mach-Zehnder modulators (MZMs), our design features are simple with more efficient power and premium flatness of comb lines, the number of generating frequencies lines was 64 with a power stronger than -2 dBm over a 340 GHz bandwidth from a single continuous laser diode. Different chirping factor (α) of MZMs are implemented (3, 5, 7), as the results the best results related to α=5 with extra flatness, the system was designed and simulated by VPI design suite 9.8.

Pesticide residue has become as one of the major food adulterants as a result , rapid, simple, spectrophotometric method for pesticide residue measurement (bifenthrin, glyphosate) in milk sample based on UV-Vis spectrophotometer and Artificial neural network had been developed .The developed system detecting the milk contaminants like pesticide residue and classified it based on absorption spectrum. The hybrid system consists of UV-Vis spectrophotometer and neural package. The detection and classification processes depend on the readout of the UV-Vis spectroscopy to achieve the detection and recognition of all the samples by using Levenberg-Marquardt back propagation (LM-BP) neural network algorithm. The reported classification rate accuracy reached above 99.98%.

(FSO) Frees Space Optical communication is considered one of the communication systems types which uses light to carry the data between transmitter and receiver. It is previously known that the system which uses single input single output (SISO) technique is suffered from high rate of attenuation due to obstacles and various conditions of weather. The impacts of weather conditions which influence on the performance of the overall FSO communication system. Wavelength division multiplexing (WDM) is vastly utilized in FSO communication to take advantage of channel capacity with high efficiency. Multiple input multiple output (MIMO) is used in FSO systems to maintain perfect availability of transmission path. The study is proposed represent by integration between WDM and MIMO techniques to get FSO-WDM-MIMO system to enhance the performance of FSO communication system. Also in this study Comparison between the proposed system and the normal FSO-WDM system is made in terms of quality factor and transmission range under different weather attenuation. The proposed system FSO-WDM-MIMO system shows promising results in the performance and the quality of the received signal. The enhancement is achieved in transmission range, received power of optical signal, best quality factor, minimum bit error rate (BER) under different weather conditions.

The global demand for high-speed communication has increased dramatically over the past few years when data beginning to dominating of the traffic according to the Cisco Visual Networking Index (VNI). Data traffic is triple between 2014 and 2020, mainly, due to developing applications that consume bandwidth such as cloud services, HD video, high quality of real-time video transmission, virtual- augmented reality (VR-AR), online- games (video games), exchange of multimedia via smartphones and the more like. In fact, in 2020, more than a million minutes of multimedia (video) content is transiting the IP network every second according to the VNI; and the demands will exceed the capability of the current (core) internet backbone systems, in which optical communications are the main infrastructure. In this paper, the focus was on reviewing the mechanisms used for the most important and most effective techniques used to increase the capacity of optical transmission systems, namely Nonlinear Compensation (NLC) which work to reduce the nonlinear impairments that represent the main intrinsic challenges and the main capacity limitations facing the optical systems. The traditional NLC techniques were determined based on the approximate solution of the Nonlinear Schrodinger Equation (NLSE) through Digital Back Propagation (DBP), or Split- step Fourier Method (SSFM). however, their implementation demands excessive signal processing resources, and high-level accurate knowledge. A completely new approach that uses artificial intelligence (AI) algorithms to identify and solve these impairments has been studied in this paper. Traditional NLC techniques are reviewed in the first part to mitigation the nonlinearities and estimate the quality of transmission (QoT). Whereas in the second part, we review the uses of AI techniques that have been studied in applications related to monitoring performance, reduce nonlinearity, and quantify QoT. Finally, this paper presents a summary with a conclusion and outlook for development and challenges in optical fiber communication systems where AI is predictable to represent a hot major role in the near future.

Today, optical systems are important element that suit the consumer to expand important services in this civilized age. These networks are developed on the basis of the optical fiber bandwidth frequency using optical spread spectrum system and through Optical Code Division Multiple Access technologies OCDMA and a good solution for high bandwidth networks. In this message, we propose a system to increase the number of users. To meet future demands these networks should be developed where OCDMA is designed and simulated for the purpose of expanding the communication network by increasing the data transfer rate. To add the numeral of users in the network should check a encoder/decoder OCDMA system. In addition, Optical Fiber system (OFS) is utilized with some of incoherent (SAC- OCDMA) code using hadamard code to reduce the Multi Access interference (MAI) effect in OFS. MAI is one of the most important factors affecting system performance. In this simulator the transmitter adopts Mach- Zehnder Modulators (MZM) and light source for multi-source electrical data transmission where it provides low cost, high transmission power and easy system implementation. Using the program optisystem Ver.15.

The streaming of wireless applications and growth in bandwidth demand led to huge interest in Ultra Wide Band (UWB) technology. In this paper a Wavelength Division Multiplexing (WDM)-UWB system based Optical Wireless Communication (OWC) is designed and simulated with two modulation formats OOk and QAM at three bit rates values(1Gbps, 2.5Gbps and 5Gbps). In the designed system, two methods to generate UWB pulses are proposed and demonstrated, optical method based cross-gain modulation (XGM) in a Semiconductor Optical Amplifier (SOA) and the electrical method depends on the differentiation of the Gaussian pulse. The full width half maximum (FWHM) of the generated pulses (monocycle and doublet) are 32 ps, 19ps for optical method and2.2 ns, 1.9ns for electrical method. All the generated pulses are compatible with the Federal Communications Commission (FCC) rules . In order to understand the linear and nonlinear effects, and the maximum achievable reach at each modulation scheme, the performance of the system is tested under four cases of weather conditions: clear, rainy, fog and snow weather with single channel and 8-WDM channels at 100GHz, 75GHz and 50GHz channel spacing.

In this paper wireless optical communication system (FSO) is designed through the use of software (Optisystem) . The paper also study the effect of atmospheric dust on the performance of communication system (FSO), the effect of dust concentration on the visibility by taking a different concentrations of dust (9, 20, 40, 60, 80 100, 120) gm / month / m2 . The effect of the visibility on the attenuation of dust concentration on each of these concentrations , and calculate attenuation of dust for the wavelengths (784 nm, 1550 nm). The Paper also deals with effect of the transmitted laser power on the transmitter range (propagation distance) where five different values of transmitted laser power (10mw, 20mw, 30mw, 40mw, 50mw) are taken and the study calculates the maximum transmitter range of each value of the transmitted power under the influence of attenuation atmospheric dust concentrations for each concentration of dust used and also for the two wavelengths (1550nm, 784nm).

In this work we present a computer simulation of a simple technique for the generation of power-efficient, FCC-compliant Ultra-Wideband (UWB) (monocycle and doublet) pulses. A Simulated system consist of a laser sources, semiconductor optical amplifier, optical modulator, fiber Bragg grating (FBG).This technique based on combination of optically reconfigurable photonic microwave delay-line filter and using the cross gain modulation (XGM) in Semiconductor Optical amplifier (SOA). In SOA the cross gain modulation (XGM) technique was used to produce a UWB monocycle pulse with a full width at half-maximum of 35 ps, by entering the output monocycle pulses from first stage to the second stage that included reconfigurable photonic microwave delay-line filter the last act as first- or second-order difference, which can be approximated as a first- or second-order derivative, after derivative the monocycle pulse the doublet pulses was obtained.

The sensor arrays are now an essential part of any communication, medical and remote sensing system. These arrays should be designed with utmost performance to ensure the maximum link efficiency. The available commercial sensor arrays design packages are expensive, complicated and cannot be easily modified to accommodate the users’ needs. This work suggests a solution that is to design an open source specialized application to serve the ever-changing needs of the users. This package is called Sensor Array Design and Optimization (SADO) and it is developed to allow the unexperienced users and the researchers to design, test and optimize their sensor arrays using effi-cient optimization algorithms. The optimization is trying to reduce the sidelobe levels to reduce the interference. The application is simple and friendly to use, with professional graphical results. The predesigned arrays configurations supplied with this package are uniform and random arrays. The built in optimization algorithms are: Artificial Bee Colony (ABC), Biogeography-Based Optimization (BBO) and Teaching Learning Based Optimization (TLBO). The results for various designs and optimization results are also given and compared to indicate the best settings for the user. Some optimization ratios might reach about 50% that represent -3dB reduction in sidelobe level.

In this work, a practical wireless optical communication system has been proposed for the purpose of monitoring the health condition of patients who are in hospital operating on the basis of the wireless communication system and fiber sensors. The suggest practical system employ a diffuse optical broadband link technique based on laser Li-Fi the technology, Fiber Bragg grating (FBG) sensors was investigated. The focused on optical fiber sensors (pressure and temperature) for medical applications because it’s small size, immunity to electromagnetic interferences and their suitability for remote monitoring. Fiber Bragg grating (FBG) based (blood pressure, temperature) sensors is designed and implemented using a conventional laser source, Optisystem version 15. The collected data from sensors is transmitted to main unit, the suggested system tested under different operating conditions such as , optical link distance, laser power and transmitter angles, all operating conditions was successively demonstrated.

Melamine has become as one of the major food adulterants. Therefore in this article, we developed a novel method for detecting the milk contaminants like toxicity of melamine and classified it based on data spectroscopy. The developed system based on optical fiber sensor, Optical spectroscopy and artificial neural network (ANN). The system consists of an optical source, refractive index sensor (RIS), optical detector (photodiode), spectroscopy data and neural package. Where the detection and classification process depends on the read out of the RIS sensor and near-infrared spectroscopies to achieve the detection and recognition of all the samples by using LM-BP neural network algorithm. The classification rate was reported at accuracy rate reach above 99.98%.