Omnidirectional Slots Antenna

获得“2021年度国家科学技术学术著作出版基金”资助

Junping Geng,

Springer Press, Shanghai Jiao Tong University Press, 2021，

（海外版，2021年）：ISBN 978-981-15-9088-7 ISBN 978-981-15-9089-4 (eBook)

https://doi.org/10.1007/978-981-15-9089-4

（国内版，2022年8月）：全向缝隙天线技术（英文版），ISBN  978-7-313-27187-7

    Omnidirectional slots antenna with high gain, low profile, vertical polarization, even CP polarization is very difficult to design, although it is from the dipole. In this book, a novel idea that the running wave in the coaxial wire is disturbed by the orthogonal slot array on the cylindrical metal shell is introduced, which radiates the CP wave in omni-direction.

    When feeding on two ends of the coaxial wire respectively, there will appear left hand circularly polarized (LHCP) omnidirectional radiation or right hand circularly polarized (RHCP) omnidirectional radiation. By introducing the T-shaped feed structure, the coaxial wire with slot array can conveniently produce the LHCP and RHCP radiation diversity with one end feeding. In the further, combining with the directional antenna, it will generate the pattern diversity in the half-sphere space.

    The antenna of the coaxial wire with slot array can further transform into onical CP beam antenna if the coaxial wire becomes into a conical frustum. By introducing the PIN diode into the slot, the antenna of the coaxial wire with slot array can radiate the reconfigurable directional beam by switching the states of the PIN diodes. By introducing a novel switchable microwave circuit, the omnidirectional /directional pattern switchable antenna can be realized easily.

    This book proposes a continues method to develop the potentialities of the omnidirectional antenna. And the readers can study the method or ideas of the omnidirectional antenna, even graft the CP or diversity methods to other antennae.