A Ka-Band Wideband Circularly Polarized High Gain Slotted Cavity Antenna Array Using High-Order Modes and Sequential Rotation Technique

A wideband and high gain circularly polarized (CP) 4×4 slotted cavity antenna array at Ka-band is presented in this paper. The array employs a substrate integrated waveguide based slotted cavity antenna using high order cavity modes as the basic element. A two stage sequential-phase feed network is utilized to guarantee good CP performances. A prototype of the full array is simulated, and the simulated results show that a wide 3-dB gain bandwidth of 18.3% and peak gain of 25 dBic are achieved. Within the bandwidth, the |S ₁₁ | is smaller than -10dB, and axial ratio at boresight is smaller than 0.3dB.