Microwave Planar Lens Antenna Designed With a Three-Layer Frequency-Selective Surface

Abstract

A multilevel Frequency Selective Surface (FSS) formed by a non-uniform distribution of circular holes on a metallic sheet is presented. The FSS is aimed at working as a planar lens to increase the gain of the feeding aperture. The unit cell of the FSS acts as a high-pass filter that provides the necessary phase shift to focus the beam on the far-field region. The phase shift is synthesized by suitably configuring the size and position of each unit cell in the FSS. The planar lens is placed next to the feeding aperture to confer the structure a low-profile shape. A prototype has been designed, fabricated and measured. Results show an increment of 7.32 dB in the gain compared to the feeding aperture within a 7.33% bandwidth around 20.45 GHz, and a side-lobe level below −12 dB, with an aperture efficiency of 65% and a radiation efficiency above 90%.

Analysis and Design of a Metamaterial Lens Antenna Using the Theory of Characteristic Modes

“…where J n are the characteristic currents on the conducting body, λ n are the eigenvalues, and V i n is the modal excitation coefficient expressed in (2). Associated with each eigenvalue, a characteristic angle can be defined as…”

“…Metal lenses have attracted an increasing interest during the last decade due to their multiple applications [1][2][3][4][5][6][7][8][9]. In this context, different lenses have been recently proposed aimed at maximizing the gain and the efficiency of the radiating structures.…”

“…These lenses are formed by periodic structures, for example, EBG (electromagnetic band gap) or FSS (frequency selective surfaces), which provide the aforementioned characteristics in a low-profile shape. In [1,2], a type of FSS, the so-called metallic hole array (MHA), was used to design a low-profile planar lens at millimeter-wave frequencies, while in [3], an extended version was proposed, which was fed by two open-ended waveguides.…”

Dual‐polarized planar lens antenna designed with a quad‐ridged frequency selective surface

“…In order to demonstrate the feasibility of the proposal, this letter shows the design of a single lens formed by 5×5 unit cells, and illuminated by an RCHA, as illustrated in Figure . Unlike designs based on metallic hole arrays, in which the response of the cell strongly depends on the period of the cell, the unit cell of the proposed FSS is a quad‐ridged cell with orthogonal stubs that control the frequency response of the cell. Thereby, the phase shift produced for each polarization can be adjusted by just tuning the length of the stubs, what facilitates the design process.…”

Gap Waveguide Array Antennas and Corporate-Feed Networks for mm-Wave band Applications

“…Many interesting examples of lenses in the mm-wave band can be found in [24]- [27]. Moreover, its usefulness and feasibility as a solution for SATCOM antennas is emphasized in recent contributions based on printed lenses as [28]- [32]. Printed lenses ( Fig.…”