Active Radar Cross Section Reduction

This book discusses the active and passive radar cross section estimation and techniques to examine the low observable aerospace platforms.

This book discusses the active and passive radar cross section (RCS) estimation and techniques to examine the low observable aerospace platforms. It begins with the fundamentals of RCS, followed by the dielectric, magnetic and metamaterials parameters of the constituent materials and then explains various methods and the emerging trends followed in this area of study. The RCS estimation of phased array including the mutual coupling effect is also presented in detail in the book. The active RCS reduction is carefully touched upon through the performance of phased arrays, sidelobe cancellers and mitigation of multipath effect. Providing information on various adaptive algorithms like least mean square (LMS), recursive least square (RLS) and weighted least square algorithms, the authors also mention the recent developments in the area of embedded antennas, conformal load bearing antenna, metamaterials and frequency selective surface (FSS) based RCS reduction.

This reference describes techniques for controlling the RCS of targets, provides analytical methods for estimating RCS, develops models for the design of low RCS targets and antennas, and discusses several RCS enhancement techniques.

The leading text and reference on radar cross section (RCS) theory and applications, this work presents a comparison of two radar signal strengths. One is the strength of the radar bean sweeping over a target, the other is the strength of the reflected echo senses by the receiver. This book shows how the RCS "gauge" can be predicted for theoretical objects.

This book presents a comprehensive review of plasma-based stealth, covering the basics, methods, parametric analysis, and challenges towards the realization of the idea. The concealment of aircraft from radar sources, or stealth, is achieved through shaping, radar absorbing coatings, engineered materials, or plasma, etc. Plasma-based stealth is a radar cross section (RCS) reduction technique associated with the reflection and absorption of incident electromagnetic (EM) waves by the plasma layer surrounding the structure. A plasma cloud covering the aircraft may give rise to other signatures such as thermal, acoustic, infrared, or visual. Thus it is a matter of concern that the RCS reduction by plasma enhances its detectability due to other signatures. This needs a careful approach towards the plasma generation and its EM wave interaction. The book starts with the basics of EM wave interactions with plasma, briefly discuss the methods used to analyze the propagation characteristics of plasma, and its generation. It presents the parametric analysis of propagation behaviour of plasma, and the challenges in the implementation of plasma-based stealth technology. This review serves as a starting point for the graduate and research students, scientists and engineers working in the area of low-observables and stealth technology.

The design and development of low radar cross section (RCS) phased array has been a challenging subject in stealth technology. The frequency selective surface elements act as absorbers in specific frequency band and facilitate gain enhancement and reduction of antenna RCS. This book presents a comprehensive EM design and analysis of such low-profile patch arrays with high impedance surface-based ground plane. It explains how to determine radiation mode RCS of low-profile antenna arrays with arbitrary configurations. Detailed descriptions of design, workflow of determining radiation and scattering behavior of antenna arrays have been supported with schematics, tables, and illustrations. Aimed at engineers and researchers for RCS, antenna engineers and graduate students in electrical engineering and electromagnetics, it • Discusses both radiation and scattering features of both planar and conformal HIS-based low profile antennas • Describes the theoretical background, design, simulations and analysis of low RCS phased array in detail • Presents the physics behind the resultant radiation and scattering characteristics of designed antenna array • Helps readers understand design and analysis of low RCS antenna array without any degradation in its radiation performance • Includes figures, schematics and illustrations to provide comprehensive descriptions of both radiation and scattering characteristics of phased arrays of different configurations

ELECTROMAGNETIC METAMATERIALS The book presents an overview of metamaterials current state of development in several domains of application such as electromagnetics, electrical engineering, classical optics, microwave and antenna engineering, solid-state physics, materials sciences, and optoelectronics. Metamaterials have become a hot topic in the scientific community in recent years due to their remarkable electromagnetic properties. Metamaterials have the ability to alter electromagnetic and acoustic waves in ways that bulk materials cannot. Electromagnetic Metamaterials: Properties and Applications discusses a wide range of components to make metamaterial-engineered devices. It gives an overview of metamaterials’ current stage of development in a variety of fields such as remote aerospace applications, medical appliances, sensor detectors and monitoring devices of infrastructure, crowd handling, smart solar panels, radomes, high-gain antennas lens, high-frequency communication on the battlefield, ultrasonic detectors, and structures to shield from earthquakes. Audience Researchers and engineers in electromagnetic and electrical engineering, classical optics, microwave and antenna engineering, solid-state physics, materials sciences, and optoelectronics.

The objective of this thesis is to investigate and evaluate the effectiveness of radar cross section (RCS) reduction by means of the geometric control of discontinuities using serrated edges. Although the use of serrated edges for RCS reduction can be clearly seen on stealth aircraft such as the Northrop B-2, and was mentioned in several papers and references, not much data on the reduction magnitude, the associated geometry, or the design methodology are available in the open literature. Parameters of interest include the number of basic serration cells (triangles) required per wavelength, and the aspect ratio of the triangles that form the zig zags. An infinitely thin metallic plate is considered for the analysis. The RCS of such a plate with serrated edges is computed and compared against the RCS of a plate of the same sized without serrated edges. The infinitely thin assumption is valid if the wing of the aircraft, which is represented by the plate, is thin compared to the wavelength. The results obtained show significant reduction in RCS.