A dual-band circularly polarized (CP) antenna with wide half power beamwidths (HPBWs) for compass navigation satellite system (CNSS) applications is proposed in this paper. The CP radiation is realized by feeding four sequentially rotated U-shape patches shorted to the ground at both ends of them with a 90°phase difference feeding network. Loading four parasitic arc-shape patches with one end shorted to the ground provides the dual-band CP operation. Experimental results show that the proposed antenna exhibits two overlapped impedance and axial ratio relative bandwidth of 2.8% and 3.3%. Wide HPBWs of over 122°at center frequencies (1.268 and 1.561 GHz) of the CNSS-2 B3 and B1 bands are obtained. With these good performances, the antenna can be a good candidate for CNSS applications.
Abstract-This letter presents a broadband circularly polarized (CP) crossed dipole antenna with wide axial ratio (AR) beamwidth. The antenna consists of a crossed dipole fed by two baluns, a wideband feed network and a cylindrical metallic cavity. To broaden the beamwidth, circular arms are introduced. Meanwhile, the metallic cavity is utilized to broaden the AR beamwidth. Measurements show that the antenna has an impedance bandwidth of 70.6% (1.87-3.91 GHz) for voltage standing wave ratio (VSWR) ≤ 2 and a 3-dB AR bandwidth of 62.4% (1.92-3.66 GHz). In addition, the 3-dB AR beamwidth of the antenna is larger than 100 • , and the gain varies from 4 dBic to 6 dBic over the whole CP operation bandwidth. Owing to the high-gain and wideband operation, the proposed CP antenna is potentially capable for satellite applications and high-gain applications.
A frequency reconfigurable antenna array is presented. The array consists of eight arms with two different feed networks. By controlling PIN diode switches, high frequency array with four dipole elements and low frequency array with two dipole elements can be obtained, respectively. Resonant frequencies within the ranges of 1.0-2.5 GHz (Case I) and 2.5-6.0 GHz (Case II) can be achieved, which translates into an overall tuning ratio of 6:1 (1.0-6.0 GHz) for the antenna array. The proposed antenna array is simulated, fabricated, and tested with good agreement between measurements and simulations.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.