Baert & Robin Theunis.

Features:
Good radiation efficiency. Most FR4-based patches have terrible efficiency because FR4 is very lossy at 5.8 GHz
Good axial ratio, not just directly perpendicular to the patch but also off-center
Note: The PCBs must use 1.0 mm thickness FR4 material

Specifications:
Center frequency: 5.8 GHz
Bandwidth: 660 MHz (5.47 6.13 GHz)
Matching: S11 < -20 dB, VSWR < 1.22 (at center frequency)
Axial ratio: < 1.3
Antenna gain: 9.4 dBi
Half power beam width: 55 (horizontal and vertical)
Radiation efficiency: 83.5%
Diameter of large disk : 5.94cm
Diameter of small disk: 2.46cm

Package included:
1 x Triple Feed Patch-1 5.8GHz 9.4dBi Directional Circular Polarized FPV Antenna
1 x Extended cable for RPSMA Connection