A Hexaband Quad-Circular-Polarization Slotted Patch Antenna for 5G, GPS, WLAN, LTE, and Radio Navigation Applications

A hexaband, quad-circular-polarization (CP) slotted patch antenna for 5G (3.5 GHz), GPS L5 (1.17 GHz), GPS L1 (1.57 GHz), wireless local area network (WLAN) IEEE 802.11b/g/n (2.4 GHz), LTE(Long Term Evolution) (0.7 GHz), and radio navigation (1.3 GHz) applications is proposed in this letter. Primarily, the patch antenna is optimized to excite the modes TM
₁₀₀
, TM
₁₁₀
, TM
₂₁₀
, and TM
₂₂₀
at 0.7, 1.17, 1.57, and 2.4 GHz, respectively, while being fed by a single microstrip line. Then, the feeding microstrip line is tuned such that three additional hybrid modes EH
₁
, EH
₃
, and EH
₄
are excited to resonate at 1.3 GHz and a contiguous band 2.7-3.6 GHz. Meanwhile, a rotated and inverted S-shaped slot is etched on the patch metal to split surface currents of each of the modes TM
₁₁₀
, TM
₂₁₀
, EH
₃
, and EH
₄
into two orthogonal and 90
^°
phase-shifted versions, enabling the antenna to radiate CP waves at 1.17, 1.57, 3.18, and 3.5 GHz. While supporting quad-band CP operation, the proposed antenna is simply proximity-fed by a single microstrip line, which omits the need for external feeding networks and reduces the cost and complexity. The proposed antenna gain ranges from 3 to 9 dBi/dBic over operating bands.