A Compact Dual-Band Circularly Polarized Antenna with Wide HPBWs for CNSS Applications

Abstract

A compact dual-band circularly polarized antenna with wide half-power beamwidths (HPBWs) for compass navigation satellite system applications is proposed in this paper. The CP radiation is realized by arranging four compact dual-band inverted-F monopoles symmetrically to the center point, where the four monopoles are excited with a 90° phase offset through a compact sequential-phase feeding network. The compactness of the dual-band inverted-F monopole is realized by inserting two chip inductors in the horizontal portion of the monopole. The overall dimension of the antenna is only 0.211λ0 × 0.211λ0 × 0.057λ0, where λ0 is the corresponding free-space wavelength at 1.268 GHz. Experimental results show that the proposed antenna exhibits two overlapped impedance and axial ratio bandwidths of 50 MHz (1.236–1.286 GHz) and 40 MHz (1.532–1.572 GHz). Wide HPBWs of about 120°/125° and 121°/116° (XOZ/YOZ planes) at center frequencies (1.268, 1.561 GHz) of the CNSS-2 B3 and B1 bands are obtained, respectively. With these good performances, the antenna can be a good candidate for CNSS applications.

Beamwidth-Enhanced Low-Profile Dual-Band Circular Polarized Patch Antenna for CNSS Applications

“…Table 2 compares our design with some previous dualband CP antennas. It is observed that the proposed antenna exhibits similar HPBW with other antennas [9][10][11][12] at the upper center frequency. However, at the lower center frequency, the HPBW of the proposed antenna is smaller than those in [10,11].…”

“…It is observed that the proposed antenna exhibits similar HPBW with other antennas [9][10][11][12] at the upper center frequency. However, at the lower center frequency, the HPBW of the proposed antenna is smaller than those in [10,11]. Although the antenna in [10] is better than the proposed structure, cavity has to be used, which increases design complexity and cost.…”

“…Although the antenna in [10] is better than the proposed structure, cavity has to be used, which increases design complexity and cost. In the item of impedance bandwidth and 3 dB AR bandwidth, the proposed antenna shows better performance than the antennas in [9,11,14]. However, compared with [10][11][12][13], the proposed antenna has smaller volume and lower profile.…”

“…In the item of impedance bandwidth and 3 dB AR bandwidth, the proposed antenna shows better performance than the antennas in [9,11,14]. However, compared with [10][11][12][13], the proposed antenna has smaller volume and lower profile. In summary, the proposed antenna features the characteristics of wider bandwidth and HPBWs with compact dimension and low profile.…”

“…By using stacked cone patches and a dual-ring cavity, the HPBWs are 135°and 112°at the two center frequencies. In [11], a compact dual-band CP antenna with wide HPBWs is proposed by using four compact inverted-F monopoles, and cross dipoles combined with the cavity-backed reflectors are also presented [12]. However, high profile, complex in geometry, and high cost are generated by the structure.…”