Preface

Nowadays, hundreds of millions of people around the world are involved in cellular and noncellular wireless communications. It is purely a matter of convenience: receive and make audio and video calls at your leisure, send and receive SMS, MMS, etc., surf the WEB and send e-mails, or reach formats of online messages, anytime and almost everywhere. The mobile phone has become a fashionable and everyday object. In the present "information age," various subscribers find the necessity to access data while on the move or need to be connected 24 hours a day, 7 days a week to the outside world. Moreover, subscribers located at helicopters and aircrafts also want to be serviced any time and in any place from ground-based radio networks with a good quality of service (QoS) and grade of service (GoS).

During the past century, the cellular network has gone through three generations (from 1G to 3G). The first generation (1G) of cellular networks was analog in nature. To accommodate more cellular phone subscribers, digital TDMA (time-division multiple access), FDMA (frequency-division multiple access), and CDMA (code-division multiple access) technologies were used in the second generation (2G), to increase the network capacity. With digital technologies, digitized voice can be coded and encrypted. Therefore, the 2G cellular network is also more secure.

The third generation (3G) integrates cellular phones into the internet by providing high-speed packet-switching data transmission in addition to circuit-switching voice transmission. The 3G cellular networks have been deployed in some parts of Asia, Europe, and the United States since 2002, and are now widely deployed all over the world (full information on the matter can be seen in the books [1-12] and in bibliography therein).

By 2009, it had become clear that, at some point, 3G networks would be overwhelmed by the growth of bandwidth-intensive applications like streaming media. Consequently, the industry began looking for data-optimized technologies, with the promise of speed, capacity, and data rates improvements, with emphasis on GoS and C/I (carrier to interference ratio), especially in urban or suburban environments, with different density and rates of calls and/or data flow which can change at any time [13, 14].

Moreover, the demand for mobile data access is intense and will continue to increase exponentially in the foreseeable future. The only clear way to increase the capacity by the orders of magnitude required over the recent and the next decade is by adding more network infrastructure. These trends require fundamentally new network approaches to deploying such infrastructure in a cost-effective manner [13, 14].

A key recent trend in this regard is the use of femtocells overlaid throughout the traditional tower-based network. These small, inexpensive, and short-range access points can be deployed either by the end user or by the service provider and typically occupy licensed spectrum and have an IP backhaul [15-18].

There are several issues in the macrocell networks, especially in urban or suburban areas with medium or high density of cellular users. When mobile users are within a range close to the macro antenna, the C/I is about , which means good capacity and good data rates of the channel. However, when mobile users are approaching toward the edges of a cell, especially inside buildings, the C/I gets reduced (about ), which means that users are more susceptible to interference and obtain very low data rate [19]. To solve this problem, communication operators went to consult new technologies, such as femtocell, to improve the capacity and data rates of the channel [20-22, 11, 12, 23-29].

This is why the fourth-generation (4G) cellular networks are based on the advanced technologies and the so-called adaptive/smart antennas, combined with multiple-input-multiple-output (MIMO) configurations. These, combined with cellular planning strategy, from macrocell to femtocell networks, are needed to satisfy the increasing demand for the implementation of modern terrestrial wireless systems [1-5, 13].

Therefore, this book, as a continuation and extension of the two books published in 2007 and 2014, respectively (see [11, 12]), deals now with new wireless networks, from fourth generation (4G) to fifth generation (5G), in their historical perspective, and accounting for the corresponding so-called physical layer of each of them, such as multicarrier MIMO techniques, orthogonal frequency-division multiplex (OFDM), orthogonal frequency-division multiple access (OFDMA), LTE-MIMO, and other advanced technologies.

This book has been arranged to account for several current and modern wireless networks and the corresponding novel technologies and techniques based on the main aspects of "physical layer" - radio propagation phenomena in various terrestrial wireless communication links. The practical aspects of the presented approach can be easily transferred to atmospheric (aircraft) and satellite communication links. These aspects have been described in detail in [11, 12]. In [12], the main aspects of cellular and noncellular multiple-access networks based on standard technologies, such as frequency-division multiple access (FDMA), time-division multiple access (TDMA), and space-division multiple access (SDMA), which were mostly created for 3G network operational characteristics prediction, such as GoS, QoS, data stream capacity, and spectral efficiency passing such types of wireless networks, are briefly described.

As mentioned above, during the recent decades new advanced technologies were presented, such as MIMO, based on the usage of multibeam adaptive antennas, OFDM and OFDMA multiple-access techniques, and multicarrier service based on the integration of femto/pico/micro/macrocell concepts of cellular layout deployments. Therefore, this book is intended to appeal to any scientist, practical engineer, or designer, who is concerned with the operation and service of various radio networks, current and modern, including personal, mobile, aircraft, and satellite communication.

The book is composed of four parts, consisting 10 chapters. Part I includes two chapters. Chapter 1 briefly describes the well-known networks-from 2G to 3G - in a historical perspective. In Chapter 2, the corresponding 2G to 3G technologies and networks are presented in brief, describing their advantages and disadvantages.

Part II consists of three chapters. Chapter 3 illuminates the so-called physical layer of the network, based on those propagation models in terrestrial communication links which have been found as more attractive to the real land communication through their comparison with the recent experiments carried out in the built-up terrain. Chapter 4 presents the polarization diversity analysis for networks beyond 4G and gives comparative analysis of depolarization effects and the corresponding path loss factor. Various land areas are considered: rural, mixed residential, suburban, and urban, based on the results obtained from the corresponding stochastic multiparametric approach as a combination of physical "layer" based on the propagation phenomena of radio waves in such kinds of the terrain and the statistical description of the terrain features. Chapter 5 discusses, via the same stochastic multiparametric approach, the positioning of any subscriber located in the areas of service, both for land-to-land and land-to-atmosphere communication links. Positioning is becoming actual with the development of networks of fourth and fifth generations.

Part III consists of one chapter. Chapter 6 illuminates the techniques of how to plan different integrated femto/pico/micro/macrocell deployments for increasing of the GoS of the multiuser 4G and 5G networks. Part IV consists of three chapters. In Chapter 7, the reader will meet with new technologies of time and frequency dispersion for the currently used 4G networks and the upcoming 5G new networks. In Chapter 8, MIMO modern network design in space and time domains is presented along with different techniques of signal data capacity and spectral efficiency based on the universal stochastic approach. Then, in Chapter 9, a MIMO network based on multibeam adaptive antennas integrated with modern LTE releases is discussed showing that the usage of MIMO system with adaptive multibeam antennas can significantly increase the capacity of signal data transmitting via LTE networks and users' layout in the areas of service, that is, increase grade of service and quality of service of modern networks beyond 4G. Part V consists of only one chapter-Chapter 10 - which deals with mega-cell satellite networks for land-to-satellite and satellite-to-land wireless communications. Here, the most adaptive and experimentally proved models are presented as a physical-statistical...