On the multi‐resonant antennas: Theory, history, and new development

Abstract

A survey of multi‐resonant antennas is comprehensively presented, with emphasis on theoretical framework, design approaches, and practical examples. This article begins with a brief history of the multi‐resonant dipole theory, and then concentrates on the design approaches that have been developed to typical, basic antenna elements, for example, electric dipole antenna, slotline antenna, loop antenna, complementary dipole antenna, and microstrip patch antenna. Design examples for different practical applications are then raised. In final, the multi‐resonant antenna design approach is summarized and compared to some relevant antenna design techniques.

Low‐profile complementary dipole antenna under quadruple mode resonance with nearly equal E‐ and H‐plane patterns

“…Although the quadruple resonance operates in a narrow band, its wideband operation can be implemented by modifying the shapes of ground, slot and dipoles. [51][52][53][54][55] Alternatively, the multi-resonant dipole concept can be incorporated to the dipoles to yield wideband designs, [56][57][58] too. The nearly equal E-and H-plane radiation patterns exhibits its great potential for application as planar antenna feeds for parabolic reflector antennas, and low-profile vehicular antennas to be integrated with bulky metal bodies.…”

Wide beamwidth planar self‐balanced magnetic dipole antenna with enhanced front‐to‐back ratio

“…As numerically and experimentally validated, it is seen the FBR of a planar antenna can be effectively to over 30 dB with the HPBWs broadened to 115° to 130° and 90° to 87° in both principal‐cut planes within an available bandwidth up to 16%. For future broadband designs, the multi‐resonant concept can be further introduced and emerged with the proposed design approach. The proposed design approach has provided clear physical insights into FBR enhancement and beamwidth broadening techniques for planar antenna designs.…”

Triple‐resonant wideband 1.5‐wavelength sectorial dipole antenna

“…An impedance bandwidth of 73.3%, stable radiation patterns with gain fluctuation less than 2.4 dB, low cross polarization level of À27 dB, and average boresight gain of 6.1 dBi have been successfully achieved. Compared to its few dual-resonant counterparts, [6][7][8][9][10][11][12] the proposed antenna can exhibit a wider impedance bandwidth, better polarization purity, and maintain stable radiation characteristic. Compared with the triple-resonant and full-wavelength counterparts, 3,[14][15][16] the proposed antenna has the simplest configuration without incorporating external feed accessories.…”

“…Based on the empirical equations in references, 6,7 the length L s1 and the width W s1 of the stubs at β 1 can be approximately equal to one-quarter and one-tenth wavelength of the TE 9/5,1 mode, respectively. Similarly, the length L s2 and the width W s2 of the slits at β 2 can be approximately equal to one-quarter and one-twentieth wavelength of the TE 3,1 mode, respectively.…”

“…Recently, the multimode resonance concept has been advanced as one of the most popular wideband antenna designed techniques by simultaneously exciting multiple resonant modes to broaden the available radiation bandwidth, relatively simple configuration can be yielded. [6][7][8][9][10][11][12][13][14][15][16] In order to simultaneously excite multiple resonant modes within a single radiator, the size of the radiator should be initially set to about one-wavelength. 10,11 Thus full-wavelength dipole antennas 3,[10][11][12][16][17][18] have been drawn more and more attention recently.…”