Leaky‐Wave Antennas

Abstract

The radiation characteristics, main applications, design techniques, and practical implementations for the class of leaky‐wave antennas are considered. The basic relations between the propagation properties of open waveguides, on which these antennas are based, and the relevant features of the radiation patterns are discussed, exploiting the leaky‐wave concept. The principal radiative properties as main‐beam direction, beamwidth, radiation efficiency, scanning behavior, and sidelobe level are described. The various steps of a practical design are outlined. Examples of proposed structures derived from metallic, dielectric, and printed waveguides are reported. Accounts for measurement procedures and practical operation are given.

Application of FDTD Method to the Analysis and Design of Leaky-Wave Antennas at Microwaves and Millimeter Waves

“…As is known, the phase constant is related to the direction θ m of maximum radiation in the longitudinal (elevation) plane, while the attenuation constant is related to the width Δθ of the emitted beam, according to the relations [1]:…”

“…As is known, the principal radiation characteristics, that are the direction of maximum radiation and the width of the radiated beam, are related in a simple way to the real and imaginary parts of the complex propagation constant, respectively [1]. Moreover, it is possible to get a scan of the emitted beam, on the longitudinal (elevation) plane, through a variation of frequency, without the need of mechanically rotating the structure.…”