Combined Triangle Quarter-Wavelength Patches and Their Application to High-Gain CP Antenna

A modified triangle quarter-wavelength patch is proposed in this letter, and a compact circularly polarized (CP) antenna is designed by combining two of them. The evolution process of the combined modified triangle quarter-wavelength patches is depicted, and the current distribution is analyzed to illustrate the right-hand circularly polarized radiation generated by the designed antenna. In order to achieve better performance, a subarray with high-gain radiation characteristics consisting of four radiators and a power distribution network is designed and fabricated within a compact size of 0.176 λ
₀
²
and thickness of 0.026 λ
₀
. The measured maximum gain is up to 8.4 dBic at 1.935 GHz, and the gain is flat in the operating frequency band with maximum ripple less than 0.9 dB.