A Compact Broadband Loop Complementary Source Antenna With Switchable Tilted Beams for Intelligent Communication

A compact broadband loop complementary source antenna with four switchable tilted beams is proposed in this paper. The antenna is constructed by adding vertical quarter wavelength shorting pins to a horizontal four-leaf-clover-shaped loop patch. A packaged microstrip line structure is developed to excite different ports of the antenna. The complementary antenna features a wide impedance bandwidth of 56.5%, covering from 6.07 to 10.85 GHz, and the profile height of the proposed structure is 0.165λ<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0</sub> at the operating frequency of 8.46 GHz. In addition to its broadband and tilted radiation performances, the antenna can generate four switchable tilted beams in different directions to cover the entire hemispheric space. Measured results show that a gain of 7.89 dBi is achieved. Compared to available works, the proposed antenna demonstrates a notable bandwidth improvement, making it a preferable candidate for future intelligent wireless communication.