Parallel-Fed Planar Dipole Antenna Arrays for Low-Observable Platforms

Abstract

In aerospace vehicle phased arrays are mostly of planar configuration. The radar cross section of the vehicle is mainly due to its structure and the antennas mounted over it. There can be a situation when the signatures due to antennas dominate over the structural RCS of the platform. This necessitates the study toward RCS reduction and control of antenna/ array RCS. In this book, scattering of parallel-fed planar dipole arrays is determined in terms of reflection and transmission coefficients at different levels of the array system. The planar dipole array is considered as stacked linear dipole array along the y-direction. A systematic step-by-step approach is used to calculate the RCS pattern including the finite dimensions of dipole antenna element. The mutual impedance between the dipole elements for planar configuration is determined. The scattering till second level of couplers in parallel feed network is taken into account. Phase shifters are modeled as delay line. All the couplers in the feed network are assumed to be four-port devices. It is shown that the array RCS can be reduced considerably toward low observable platform by an optimization of array design parameters, even in the presence of mutual coupling. This book presents a systematic step-by-step analytical formulation for RCS of planar half-wavelength center-fed dipole arrays through various schematics and illustrations. The adequate analytical description and analysis discussed in this book will be useful for students, researchers, and design engineers of phased arrays.