Optical Wireless Communications for Broadband Global Internet Connectivity

Fundamentals and Potential Applications

Arun K. Majumdar

• Publisher: Elsevier
• Year: 2018
• ISBN:
  9780128134061
• Topic: Physical Sciences
• Subtopic: Optics & Light

Optical Wireless Communications for Broadband Global Internet Connectivity: Fundamental and Potential Applications provides a comprehensive overview for readers who require information about the fundamental science behind optical wireless communications, as well as up-to-date advanced knowledge of the state-of-the-art technologies available today. The book is a useful resource for scientists, researchers, engineers and students interested in understanding optical, wireless communication systems for global channels. Readers will find beneficial knowledge on how related technologies of optical wireless communications can be integrated into achieving worldwide Internet connectivity.

• Presents an in-depth coverage of information on optical wireless communication in a single source
• Combines the fundamentals with the most recent advanced technology of achieving global Internet access and connectivity
• Provides derivations of the mathematical equations
• Includes between chapter sections where information and learning from one chapter is connected to other chapters

Chapter 1

Introduction

Abstract

This book covers various topics relevant to establishing worldwide optical wireless access independent of terrestrial infrastructure for Internet connectivity. The purpose of this initial chapter is to provide the technical background needed to understand and appropriate the following chapters, as well as to establish the connections and continuity among them, and point out how free-space optics is needed for accomplishing global all-optical network around the world and broadband data link between two points, either fixed or moving, and air-borne, satellite and space for data links between distant global locations for worldwide backbone. OWC-based Internet connectivity can thus provide global broadband Internet access to anywhere anytime.

Keywords

All-Optical Network; FSO; GEO; Global Internet Connectivity; LEO; OWC

1.1. Introduction

Chapter 1 is an introduction to broadband global Internet connectivity: the need, the existing technology, and the need for free-space optical (FSO) communications in the proposed technological plans for achieving this goal. Wireless Internet access can be delivered through mobile phone towers to computers, cell phones, and other digital devices using portable modems that can be built into laptop computers, tablets, cell phones, and other devices. This chapter discusses statistical projections for the number of Internet users worldwide by 2018. Specifically, it is important to note the following: globally, mobile data traffic will grow 11-fold from 2013 to 2018, a compound annual growth rate of 61% reaching 15.9 exabytes/month by 2018 (1 exabyte ∼1 billion gigabytes); the total Internet video traffic will be 75% of all Internet traffic in 2018, up from 57% in 2013; and finally, broadband speed will triple by 2018. This chapter explains why optical wireless communication (OWC) is a viable technology to solve these huge demands for Internet access as well as the recent development of the relevant technology developments such as LED-based hotspots to replace Wi-Fi and Li-Fi using visible light communication. Providing Internet access to more people in the world will allow taking advantage of all the opportunities available over the Internet. The UN reports and declares Internet access a human right.

It is therefore obvious that the demand for bandwidth in communications, either fixed platform-based or mobile, is growing as the numbers of users worldwide is increasing significantly. Future increasing demand will continuously grow higher in the next decade for high-quality multimedia services and for developing more efficient access networks addressed by a number of technologies to meet the end users' communication needs. Some of the applications where higher capacity to support various broadband wireless services are necessary include high-definition TV, broadband computer network applications, mobile videophones, video conferencing, and high-speed Internet access. Optical wireless communication can offer possible solutions to provide high-speed Internet access for broadband services to locations everywhere, including remote places. This chapter gives an overview of the book, which addresses the problem of all-optical technology for establishing global Internet connectivity and access using FSO communication and high-bandwidth, fiber-based solutions. FSO must be included in the set of solutions for meeting the bandwidth requirements of the modern Internet. FSO communication is the most practical alternative to solve the bottleneck broadband connectivity problem, and as a supplement to conventional radio frequency/microwave links. FSO is recently very active with many exciting fundamental and technological challenges to improve its performance in a range of scenarios. The data rate provided by FSO links continues to increase in both long- and short-range applications. FSO will be one of the most unique and powerful tools to address connectivity bottlenecks that have been created in high-speed networks during the past decade due to the tremendous success and continued acceptance of the Internet. The next generation of Internet connectivity will push the limits of existing infrastructure with high-bandwidth applications such as videoconferencing, streaming multimedia content, and network-enabled portable devices. Clearing these bottlenecks is crucial for the future growth and success of the contemporary Internet society. The bandwidth of optical communications access and edge networks will be needed to satisfy these demands. A scheme of FSO communication technology with optical wireless and different user connectivity involves encoder, optical source, and atmospheric channel (or fiber-optics channel), optical receiver (photodetector), and decoder [1,2].

Continued global demand for increased bandwidth and security issues, free-space optical, and fiber-based access networks are the only viable solutions to offer high-capacity Internet services to the end users. OWC is a promising technology for indoor and outdoor applications for voice and data, video and entertainment, business connectivity, disaster recovery, and data communications, and will play a significant role in future information superhighways.

A number of chapters mainly discuss the free-space optical connectivity in today's network. FSO communications refers to a line-of-sight technology transmitting modulated visible or infrared beams through the atmosphere to establish optical communications. FSO has been considered one of the most viable technologies for next-generation broadband communicating and wireless networks. The greatest disadvantage of FSO is the weather. When the communication link includes part of the atmosphere, clear-air turbulence and a possible boundary-layer turbulence (e.g., one end of the communication link is on an aircraft) cause serious phase distortions and fading to the link. FSO networks may also suffer because of insufficient availability and low reliability due to weather turbulence. Weather conditions such as fog, smog, snow, rain, and dust particles affect FSO communication performance.

This chapter gives an overview of the optical communications technologies to develop schemes for indoor, outdoor, terrestrial, and space applications and to address the immediate next challenge and today's need for providing practical solutions and systems design for global Internet connectivity. The chapter provides and explains the basics of the modular advanced communication systems that will allow worldwide access to the Internet by combining satellite communications, airborne/balloon platform, FSO wireless local area network (LAN), local multipoint distribution system, and terrestrial digital video broadcast. The chapter describes in detail the scenarios, and mentions the need for establishing bidirectional (duplex) mobile global Internet connectivity. Whereas wireless LAN offers uninterrupted connectivity in a network cell, FSO allows established broadband wireless links through air, and satellite communication provides access to fixed and mobile services and is a key element of the Internet backbone between various locations worldwide to close the Internet connectivity loop between any two or among various distant locations. The evolving technology is emerging to provide 10s to 100s of gigabits/sec (Gb/s) or more OWC-based Internet connectivity for global broadband Internet access anytime, anywhere. The ultimate goal of developing various communications technologies is to develop innovative Internet for remote areas for establishing broadband connectivity anytime, anywhere, which eventually should be cost effective and affordable for everybody. In order to achieve this goal to meet the growing demands of Internet access everywhere a number of most recent advanced technological developments worldwide are described, which are independent but closely related to Internet connectivity. Global all-optical broadband network around the world has the potential solution. Various broadband optical communication technologies and scenarios are necessary to determine conceptual designs and architectures. Some of them can be summarized as follows, and each one of them is described in detail in different chapters:

• 1. Terrestrial optical communication from one user to another user, including horizontal and slant paths
• 2. Longer distance terrestrial and connecting to the Internet (access points to optical tower via LAN, connection to fiber backbone: FSO communication as a solution for last-mile problem
• 3. Maintaining Internet connectivity on the fly
• • a. Mobile ad-hop platforms and communications, concept for optical antenna, retroreflector for automatic alignment
  • b. Small cell solution: All-optically
• 4. Optical tower to optical communication satellite
• 5. Optical ground station to optical communication satellite
• 6. Optical ground station to various optical access points/optical towers
• 7. Remote locations via optical communication satellite
• • a. Low earth orbit (LEO) to other LEOs, or between small satellites
  • b. LEO to airplane or geosynchronous earth orbit (GEO) to airplane platform
  • c. Airplane platform to ground optical tower/cells
  • d. GEO to LEO
  • e. GEO to another GEO
  • f. Constellation of satellites, small satellites, and CubeSat
• 8. Remote locations via drones, balloon, high altitude platforms (HAP) for optical communication
• 9. Internet access for Internet of Things devices to integrate with 5G communication networks
• 10. Additional innovations in design
• • a. Li-Fi–based hotspots to replace Wi-Fi in future
  • b. Modulated retroreflector based on my patent for achieving two-way (duplex) communications
  • c. Chip-based compact optical devices such as optical router, optical switching to be integrated with the optical networks systems for Internet accesses by smartphones
• 11. Quantum entanglement and communications for achieving the most secure Internet communication links over a distance

The Internet is now really a part of our social fabric and is essential to how we connect, communicate, share, and collaborate. Digital technologies, information and communication technologies, and broadband global connectivity when combined offer various opportunities to improve people's lives in worldwide societies by exchanging and sharing information. Some of the potential applications of broadband global connectivity include social connections, health, well-being and telemedicine, education, business and financial transaction, emergency response, and search and rescue. These are all possible with global Internet access and connectivity. Some of the current advanced research relevant to establishing all-optical connectivity for future optical communications includes the following: fast luminescent detector, nonlinear silicon photonic, high-speed photo...

Table of contents

• Cover image
• Title page
• Table of Contents
• Copyright
• Dedication
• Biography
• Preface
• Chapter 1. Introduction
• Chapter 2. Basics of Worldwide Broadband Wireless Access Independent of Terrestrial Limitations
• Chapter 3. Last-Mile Problem Revisited With Potential Solution for Broadband Connectivity
• Chapter 4. Fundamentals of Free-Space Optical Communications Systems, Optical Channels, Characterization, and Network/Access Technology
• Chapter 5. All-Optical Broadband Global Communications for Internet Connectivity: Free-Space Optic Links and Optical Network Architectures
• Chapter 6. Demonstration of Successful LEO/GO/Small Satellites/UAV/Airplanes to Ground Optical Communication Experiments: Opening Future Potential for All-Optical Networks Around the World for Global Internet Connectivity
• Chapter 7. Principles and Implementation of Secure Free-Space Optical Wireless Communications
• Chapter 8. Free-Space Optical Communications: Role and Integration With the Internet of Things
• Chapter 9. Potential Applications for Broadband Global Internet Connectivity
• Chapter 10. Current Recent Research and Future Directions
• Chapter 11. Conclusions and Discussion
• Index