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Radio over fiber (RoF) has found to be one of the most effective communication techniques. It has the tendency to incorporate both optical fiber and free space radio paths. In this research article, importance, benefits, and applications of RoF system are discussed in detail for futuristic networks. The performance of RoF system is visualized by modulating the data with the RF signal having same frequency at both transmitter and receiver ends. Initially, the performance is checked using non-return to zero (NRZ) format and later compared with duobinary (DB) and carrier suppressed return to zero (CSRZ). Various simulations are performed which directly affect the system performance. Important parameters such as RoF link distance, data rate, transmitter power, amplifier gain, and RF signal frequency are tested. The operation is carried out at 1550 nm wavelength and 30 GHz RF frequency. System is optimized to receive the transmitted waveforms successfully. Simulations are performed in Optisystem 17.0 and MATLAB. For the analysis, the results are plotted using Q-factor and BER values.

Previously, different types of energy management systems were planned to operate independently, but nowadays with the development of efficient energy conversion and multigeneration systems, integrated energy systems are more eminent. The synergy of different forms of energies led to more efficient and sustainable solution to meet the energy demand of the world. Energy hub is a concept of integrating and converting different form of energies to form a system combined with storage capacities to meet the energy demand more efficiently. This chapter provides the solution to the problem of optimization of energy hub. It includes the mathematical model of energy hub including different constraints associated with it. The mathematical models of electrical, heat, and cold storages are also presented in this chapter. To make the energy hub more efficient, economical, and environment friendly, different types of renewable energies have been integrated to the proposed model. The problem of optimization of energy hub has been modeled as mixed integer linear programming and solved in GAMS (General Algebraic Modeling System) software. Four different types of case studies have been performed and analyzed on the proposed energy hub model. In case 1, simple energy hub model is optimized for electrical, heating, and cooling load. In case 2, energy storages (ES) are added to the energy hub which results in a decrease of its operating cost. In case 3, renewable energy resources (RERs) are added to the same hub which further reduces its operational cost. Finally, in case 4, both RERs and ES capacities are added in the proposed model and the results show that it is more beneficial to use both simultaneously for getting maximum benefit in its operational cost.

Latency is the time delay between sending and receiving a signal during transmission due to high-latency components, the path followed by an optical signal, and many other reasons. Latency in any network may degrade the quality of a signal at the receiver. Presented paper addresses the causes and problems regarding latency in optical networks and provides solution without compromising on signal quality. Latency is a dispensable problem when we are using critical applications (video-gaming, E-banking, and live-streaming) which cannot bear even delay of few nanoseconds. To address latency problems in optical metro networks at different data rates and distances, some components in the network having high latency have been replaced with low latency components. Presented paper is providing a new arrangement of low latency components in optical metro networks to lessen overall latency of signal during transmission.

FSO (Free Space Optics) is a type of communication in which free space is used as a medium between transmitters and receivers. For this, transmitter and receiver dishes must be in line of sight for the proper transmission. In communication it has very affordable initial investment, and no license is required for this type of communication. This paper compares the advanced modulation formats i.e., AMI, Duobinary, Chirped NRZ and 33% RZ, which are the building blocks of next-generation software-defined optical networks for the 5G (fifth generation) network. Their performance is evaluated by considering different factors such as bit rates, FSO range and attenuation in different weather conditions. The signal quality of the received signal is analyzed by using Q-factor and the BER analyzer. The proposed scheme is implemented by designing different types of transmitters based on modulation formats. The work is carried out for the DWDM environment and performed in licensed version of Optisystem software v.14.

An analytical study is presented in this paper related to the emerging 5G network based on radio over fiber communication. Security of 5G front haul is ensured by using chaos in optical domain. Optical chaos generated by semiconductor laser is used for this purpose. Optical fiber is chosen to provide high bandwidth and minimum latency whereas chaos masking technique is used to implement the security features. In this work, a Radio over fiber (RoF) communication system is designed in licensed version of Optisystem software v.14.0 in which radio frequency signal is modulated on optical signal by using laser and Mach-Zehnder modulator (MZM). Chaos generation is represented by rate equations of laser. Message signal is secured by hiding it in the chaotic carrier produced by semiconductor laser. After transmission the original signal is retrieved through perfect synchronization between transmitter and receiver, thus maximizing not only Q-factor but reduced bit error rate (BER) as well. System performance is evaluated by using different lengths of optical fiber and varying laser power.

The evolving 5G technology is currently facing some huge challenges such as cost, bandwidth, network flexibility, deployment and capacity. Free space optics (FSO) is an emerging technology and viable approach to address the challenges of upcoming networks. This paper presents the performance comparison of advance variants of Return to zero (RZ) and Non-return to zero (NRZ) modulation formats in FSO communication. Detailed analysis of FSO link is carried out under various weather conditions by means of numerical simulations in which different data rates and distances are tested to evaluate the performance. The effects of different weather conditions over the performance, efficiency and availability of FSO link are analyzed on the basis of quality factor (Q-factor) of received signal. The work is performed on the licensed version of Optisystem v14.0.

Free-space optical (FSO) communication is one of the choice of researchers for most of the bandwidth hungry applications in evolving networks where the deployment of optical fiber is not directly possible as a transmission medium. In this research article, benefits, challenges, applications and role of FSO is discussed in detail for evolving networks. Further, performance of FSO communication system is tested using four channels of dense wavelength division multiplexing (DWDM). Various simulations are performed on FSO including different weather conditions, that directly affect the link performance. Many important parameters such as distance, data rate, bit error rate, amplifier gain, transmitter power, and attenuation under different weather conditions are tested in this research work. The operation of FSO communication system is carried out in the range 760-850 nm where equal channel spacing is considered for the working of DWDM communication system. Moreover, a fair comparison of proposed system is also presented for its operation in two more bands i.e. C and L-band, to show which one offers better performance. Simulation are performed in licensed version of Optisystem 14.0 and MATLAB. For the analysis of proposed system, results are presented in the form of BER and Q-factor plots.

Dense Wavelength Division multiplexing (DWDM) is a promising technology that has ability to provide potentially unlimited transmission capacity to meet the growing demand of bandwidth in optical fiber communication systems. In this paper, we have proposed a dual polarized 128-QAM DWDM communication system consisting of 8 channels. The data rate of each channel is set to 90 Gbits/sec and simulations are carried out by using single mode fiber (SMF) of 80 km. Dispersion compensation fiber (DCF) of appropriate length is used for dispersion compensation. Linear impairments are controlled by using appropriate optical amplifier in addition to the DCF. The model is tested by varying the data rates, length of SMF and filter gain. Lumped and distributed configurations of amplifiers are used to find the optimal results. Comparison of Gaussian and Bessel optical filters is also made in the proposed system. The results are presented by using constellation diagrams, EVM and BER plots in licensed version of Optisystem v.14.

Dense Wavelength Division multiplexing (DWDM) is a promising technology that has ability to provide potentially unlimited transmission capacity which meets the growing demands of bandwidth in fiber communication systems. In this paper we have proposed a bi-directional DWDM communication system consisting of 40-channels. The data rate of each channel is set to 10 Gbits/sec and simulations are carried out at fiber length of 75 km to achieve the long-haul bidirectional transmission of overall 800 Gbps. Linear impairments are controlled by using appropriate amplifier and Dispersion compensation fiber (DCF). Lumped and distributed configuration of amplifiers are used to find the optimal results. The presented solution is optimized by connecting DCF and amplifier in pre, post and symmetric configurations. Further the model is tested by using RZ and NRZ modulation schemes and varying laser’s input power. The results are presented by using Q-factor and BER plots in licensed version of Optisystem v.14.