High-gain circularly polarized millimeter-wave antenna

Improving the gain and reducing the side lobe levels of a microstrip/dielectric resonator millimeter-wave antenna

“…The patch itself is fed via a resonant slot in the ground plane by a microstrip line, which is placed on the other side. Dual-and circularly-polarized versions of this PCB-based antenna have also been implemented [2]- [3], making the latter an interesting low-cost alternative to arrays [4]- [5] for millimeter-wave applications.…”

Analytic study on CP enhancement of millimeter wave DR and patch subarray antennas

“…In the early 1980s for the first time, because of the inherent features of low‐loss and high‐efficiency, dielectric resonators were utilized as radiating elements . On the other hand, circularly polarized antennas offer many advantages due to their good resistance to polarization mismatch, multi‐path effects, and some phasing issues due to rain or snow . Examples include the cylindrical DRA excited by two microstrip line feedings, cross slot etched off the ground plate in aperture coupled patch/DR antenna, cylindrical DRA excited by dual conformal strips .…”

“…On the other hand, circularly polarized antennas offer many advantages due to their good resistance to polarization mismatch, multi‐path effects, and some phasing issues due to rain or snow . Examples include the cylindrical DRA excited by two microstrip line feedings, cross slot etched off the ground plate in aperture coupled patch/DR antenna, cylindrical DRA excited by dual conformal strips . On the other hand, because of their planar geometry, patch antennas are also utilized as elements of large arrays in plenty of applications.…”

A novel PIFA antenna for broadband circular polarization

“…However, it is necessary to comprise an external feed network such as a Wilkinson power divider, which might complicate the design of array antennas. To avoid the disadvantages stated above, [6][7][8][9][10][11][12][13] put forward other types of slot broadband circularly polarized antenna, but the published literatures show there are not enough in AR bandwidth comparing with the voltage standing wave ratio (VSWR) bandwidth. Recently, PIFA antennas [14][15][16] have been dawn much attention in antenna design with wideband characteristic, good radiation patterns, simple structure, and easy integration with other active devices, but they usually generate linear polarization.…”

“…However, the PAs operated at a large BOP has a serious problem such as poor efficiency. Therefore, several techniques such as switchingmode PAs, envelope elimination and restoration, and Doherty PAs (DPA) have been investigated to boost the efficiency [1][2][3][4][5][6][7][8][9][10][11][12]. Among these techniques, the DPAs are regarded as the promising solution due to high efficiency at a BOP without an additional circuitry [5][6][7].…”