Ultra-Wideband Integrated Circularly Polarized Tightly Coupled Array Antenna Using Sequential Rotation Technology

This paper introduces an ultra-wideband (UWB) integrated circularly polarized (CP) tightly coupled array (TCA) antenna using sequential rotation technology. The ultra-wide impedance matching property is realized by the TCA technology. And the sequential rotation technology uses 90° phase different feed to improve the axial ratio (AR). The combination of the two technologies can achieve an UWB CP array antenna. The final results show that the antenna can achieve ultra-wideband CP radiation from 6.97-18.69 GHz with AR < 3dB and VSWR < 3. Moreover, the TCA is designed in an integrated way, which makes its size very small.