Contents


Preface

With the increasing demand for antennas and narrow beam widths with beam steering capabilities, array antennas have become a wise choice as they offer versatile and flexible solutions for desired radiation patterns. The radiated field of the array depends on the main design parameters, such as the geometrical layout of the elements and their spacings, the excitation in amplitude, and/or phase of the individual elements, and finally the pattern of the individual elements. Many array synthesis techniques that use either analytical or numerical approaches have been extensively employed to improve the radiation pattern of the array. This book addresses recent techniques that aim to improve and optimize the radiation pattern of the array antenna. The book presents a concerted set of issues related to design concepts and methodologies that have recently been proposed to develop and

While most of the array pattern synthesis approaches deal with all of the elements of the array antenna, recent techniques try to offer easier solutions as only a limited number of the elements need to have their magnitudes and/or phases adjusted. Such approaches reduce the cost and complexity of the optimization process by dealing with a small number of selected elements. Whether dealing with all the array elements or a selected number of them, the analytical approaches give better insight and a more explicit way to synthesize the desired pattern. However, global numerical optimization methods have easier and shorter paths towards achieving better performance and optimum results. As the distribution of the power density in the near field of the array is required in some applications, the problem of array synthesis using numerical approaches becomes more desirable than using analytical

Beamforming techniques have been an important approach to the design and optimization of the array pattern. Here the array elements are fed through a network that furnishes the phases and magnitudes necessary to obtain the desired radiation pattern. This approach offers the capability to employ various algorithms that are intended for the next generation ultra-wideband millimeter-wave phased array antennas. This book tries to augment this recent issue to the field of array synthesis.

In compliance with the development of massive MIMO and beamforming techniques in 5G technology, increasing the number of antenna elements has become an issue for further concern. The integrated antenna, which is composed of multiple antenna elements, can be a promising candidate for the next generation of technologies. The Smart Antenna Systems (SAS) and Massive MIMO systems are giving a strong and increasing impact relative to 5G wireless communication systems. They offer many benefits in terms of performance improvements with respect to omnidi-

Therefore, this book aims to provide a good reference for practicing engineers as well as postgraduate students and researchers working in the field of antenna arrays. The book uses fundamental concepts that are necessary to explain the recent applications to provide a base on which the interested reader can either acquire new

improve the radiation characteristics of antenna arrays.

ways as the latter will involve lengthy and cumbersome derivations.

rectional antennas.
