Dual-Beam and Tri-Band SIW Leaky-Wave Antenna With Wide Beam Scanning Range Including Broadside Direction

Abstract

In this letter, a novel dual-beam and tri-band leaky-wave antenna (LWA) based on substrate integrated waveguide (SIW) structure is proposed, which has the capability of wide beam scanning range including broadside direction. The antenna consists of two kinds of periodic structures which can excite two -1st spatial harmonic waves and result in two radiation beams simultaneously. Through theoretical dispersion diagram analysis of the unit cells of two periodic structures and by applying the techniques of impedance-matching and reflection-cancelling, the open-stopbands at broadside are suppressed. Then the main beam of the proposed LWA can scan from backward to forward through broadside when frequency changes. Moreover, a tri-band application can be achieved in the dual-beam antenna by optimization of the second periodic structure. The measured results validate that the proposed SIW LWA has three operating frequency bands. In band 1 from 8.6 to 9.2 GHz, there is one beam scanning from 42 • to 71 • in the forward, in band 2 from 10 to 12 GHz, there is one beam scanning from -40 • to 4 • in the backward, and in band 3 from 12.5 to 15 GHz, there is a dual-beam scanning from -55 • to 54 • including broadside direction, which show good agreements with the simulated results. Dual-beam, tri-band, open-stopband (OSB), leaky-wave antenna (LWA), substrate integrated waveguide (SIW). INDEX TERMS

A compact circularly polarized half‐mode substrate integrated waveguide‐based leaky‐wave antenna array with wide range of dual‐beam scanning

“…19 The dispersion curve of the proposed unit cell is plotted in Figure 2 based on the S-parameters from the CST simulation. 14 As it can be seen, there is no bandgap near the broadside (around 6.8 GHz), which means the OSB has been mitigated. Figure 3 gives the simulated electric fields on the aperture of the unit cell with four different sequential feeding phases at 7.0 GHz.…”

A tunable ⵣ‐shaped microstrip leaky wave antenna based on liquid crystal

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A Dual-Beam Leaky-Wave Antenna Based on Squarely Modulated Reactance Surface

“…In this work, a superposition method based on SquMRS was used to design a dual-beam LWA, due to the capability of flexible control of phase constant and attenuation constant. Unlike using n = −1 and n = −2 spatial harmonics to generate dual-beam (β eff (−1) <k 0 , β eff (−2) < k 0 ) [29][30][31], the produced two beams in this work are both excited by the n = −1 space harmonic, and other space harmonics are all slow waves (only β eff (−1) < k 0 ).…”