This paper describes composite cavity-backed crossed scythe-shaped dipoles with wide-beam circularly polarized (CP) radiation for use in Global Navigation Satellite Systems. Each branch of the dipole arm contains a meander line, with the end shaped like a scythe to achieve a significant reduction in the size of the radiator. For dual-band operation, each dipole arm is divided into two branches of different lengths. The dipoles are crossed through a 90° phase delay line of a vacant-quarter printed ring to achieve CP radiation. The crossed dipoles are incorporated with a cavity-backed reflector to make the CP radiation unidirectional and to improve the CP radiation beamwidth. The proposed antennas have broad impedance matching and 3-dB axial ratio bandwidths, as well as right-hand CP radiation with a wide-beamwidth and high front-to-back ratio.

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Circularly polarized crossed dipole antennas are presented in this paper. A compact crossed dipole is realized with the use of a meander line and a barbed end in each dipole arm. A vacant-quarter printed ring is used as a 90 o phase delay line to achieve circularly polarized radiation. For multi-band applications, each dipole arm is divided into multi-branches with different lengths to obtain multiple resonances. These radiators can be equipped with different reflectors, such as a finite planar metallic conductor, a cavity-backed metallic conductor, and a finite artificial magnetic conductor to obtain the desired antenna radiation characteristics. These antennas are quite practical for many wireless communication systems, such as satellite communications, global positioning systems, wireless local area networks, and radio-frequency identification devices.

In this article, we propose a dual‐band angled printed dipole antenna with wide beamwidth for use in the access points of wireless local area network operating in the 2.4‐ and 5‐GHz bands.The antenna is fed by a novel integrated balun consisting of a curved microstripline and a circular slot for broadband operation. An angled dipole and two vertical copper plates on the ground plane are used to achieve wide beamwidth in the lower and upper bands, respectively. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2806–2811, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27176

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