International Journal of Computer and Applications

In recent years, free space optical (FSO) communication has gained significant importance owing to its unique features: large bandwidth, license free spectrum, high data rate, easy and quick deployability, less power, and low mass requirements. FSO communication uses optical carrier in the near infrared band to establish either terrestrial links within the Earth’s atmosphere or inter-satellite/deep space links or ground-to-satellite/satellite-to-ground links. It also finds its applications in remote sensing, radio astronomy, military, disaster recovery, last mile access, backhaul for wireless cellular networks, and many more. However, despite of great potential of FSO communication, its performance is limited by the adverse effects (viz., absorption, scattering, and turbulence) of the atmospheric channel. Out of these three effects, the atmospheric turbulence is a major challenge that may lead to serious degradation in the bit error rate performance of the system and make the communication link infeasible. This paper presents a comprehensive survey on various challenges faced by FSO communication system for ground-to-satellite/satellite-to-ground and inter-satellite links. It also provides details of various performance mitigation techniques in order to have high link availability and reliability. The first part of this paper will focus on various types of impairments that pose a serious challenge to the performance of optical communication system for ground-to-satellite/satellite-to-ground and inter-satellite links. The latter part of this paper will provide the reader with an exhaustive review of various techniques both at physical layer as well as at the other layers (link, network, or transport layer) to combat the adverse effects of the atmosphere. It also uniquely presents a recently developed technique using orbital angular momentum for utilizing the high capacity advantage of optical carrier in case of space-based and near-Earth optical communication links. This survey provides the reader with comprehensive details on the use of space-based optical backhaul links in order to provide high capacity and low cost backhaul solutions.

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Optical Communication in Space: Challenges and Mitigation Techniques

Synchronization:a universal concept in nonlinear science

In recent years, free space optical communication has gained significant importance owing to its unique features: large bandwidth, license-free spectrum, high data rate, easy and quick deployability, less power and low mass requirements. FSO communication uses the optical carrier in the near infrared band to establish either terrestrial links within the Earth's atmosphere or inter-satellite or deep space links or ground-to-satellite or satellite-to-ground links. However, despite the great potential of FSO communication, its performance is limited by the adverse effects viz., absorption, scattering, and turbulence of the atmospheric channel. This paper presents a comprehensive survey on various challenges faced by FSO communication system for ground-to-satellite or satellite-to-ground and inter-satellite links. It also provides details of various performance mitigation techniques in order to have high link availability and reliability. The first part of the paper will focus on various types of impairments that pose a serious challenge to the performance of optical communication system for ground-to-satellite or satellite-to-ground and inter-satellite links. The latter part of the paper will provide the reader with an exhaustive review of various techniques both at physical layer as well as at the other layers i.e., link, network or transport layer to combat the adverse effects of the atmosphere. It also uniquely presents a recently developed technique using orbital angular momentum for utilizing the high capacity advantage of the optical carrier in case of space-based and near-Earth optical communication links. This survey provides the reader with comprehensive details on the use of space-based optical backhaul links in order to provide high-capacity and low-cost backhaul solutions.

/pdf/optical-communication-in-space-challenges-and-mitigation-4wng3q8rfl.pdf

New high-data-rate multimedia services and applications are evolving continuously and exponentially increasing the demand for wireless capacity of fifth-generation (5G) and beyond. The existing radio frequency (RF) communication spectrum is insufficient to meet the demands of future high-data-rate 5G services. Optical wireless communication (OWC), which uses an ultra-wide range of unregulated spectrum, has emerged as a promising solution to overcome the RF spectrum crisis. It has attracted growing research interest worldwide in the last decade for indoor and outdoor applications. OWC offloads huge data traffic applications from RF networks. A 100 Gb/s data rate has already been demonstrated through OWC. It offers services indoors as well as outdoors, and communication distances range from several nm to more than 10 000 km. This paper provides a technology overview and a review on optical wireless technologies, such as visible light communication, light fidelity, optical camera communication, free space optical communication, and light detection and ranging. We survey the key technologies for understanding OWC and present state-of-the-art criteria in aspects, such as classification, spectrum use, architecture, and applications. The key contribution of this paper is to clarify the differences among different promising optical wireless technologies and between these technologies and their corresponding similar existing RF technologies.

A Comparative Survey of Optical Wireless Technologies: Architectures and Applications

A survey on LEACH and other’s routing protocols in wireless sensor network

Improved analysis of 2.5 Gbps-inter-satellite link (ISL) in inter-satellite optical-wireless communication (IsOWC) system

High speed CO-OFDM-FSO transmission system

Energy-efficient routing algorithms must handle power-limitation issue of the sensor nodes intelligently to prolong the network life of wireless networks. Accordingly, it is indispensable to collect and exchange the sensor data in an optimized way to reduce energy consumption. Subsequently, an ACO Optimized Self-Organized Tree-Based (AOSTEB) Energy Balance Algorithm for Wireless Sensor Network has been proposed that discovers an efficient route during intra-cluster communication. AOSTEB scheme operates in three phases: cluster-formation, multi-path creation, and data transmission. During cluster-formation, the desired number of sensor nodes are alleviated to the role of cluster-heads (CHs), and the remaining neighboring sensor nodes join the nearest CHs to form a cluster. Further, the multiple paths between the CH and member nodes are discovered using Ant Colony Optimization algorithm. A dynamic energy efficient optimized route is selected within a specific cluster on account of shortest distance and less energy-consumption to initiate the data exchange process within the cluster. The extensive simulation observations ascertain the efficiency of the proposed algorithm by demonstrating the prolonged network lifetime, enhanced stability period, and reduced energy consumption in contrast to the earlier reported works in wireless sensor networks.

Vishal Sharma

Papers

A survey on LEACH and other’s routing protocols in wireless sensor network

Improved analysis of 2.5 Gbps-inter-satellite link (ISL) in inter-satellite optical-wireless communication (IsOWC) system

High speed CO-OFDM-FSO transmission system

ACO optimized self-organized tree-based energy balance algorithm for wireless sensor network: AOSTEB

High speed, long reach OFDM-FSO transmission link incorporating OSSB and OTSB schemes