Leaky-Wave Antenna With Switchable Omnidirectional Conical Radiation via Polarization Handedness

Abstract

Reconfigurable antennas capable of beam-steering offer an efficient solution to optimize the use of the crowded wireless medium and can serve as a multifunction antenna. Beam-steering is often achieved by antenna geometry switching at the expense of hardware complexity. Here, polarization is used to realize beam-steering without the need of antenna geometry modification. Depending on the handedness of the feed, backward or forward conical radiation is demonstrated in a ~13λ0-long shortcircuited helically slotted waveguide antenna. Tapering the slit width with a Taylor distribution reduces the measured sidelobe levels by ~3 dB in average and results in a realized gain of 10-13 dB and 11-13 dB for right-handed (backward radiation) and lefthanded circularly polarized (forward radiation) feeding, respectively, in the bandwidth from 8.5 to 9.5 GHz.

A Linearly and Circularly Polarization-Reconfigurable Leaky Wave Antenna Based on SSPPs-HSIW

“…As the p-i-n diodes are switched on, the proposed antenna radiates L ning from −32° to 41°, including the broadside direction with the frequenc The comparisons of the previous works and the proposed polarization-reco ble LWA are shown in Table 1. As is demonstrated in Table 1, it is worth noting proposed antenna has a wide scanning angle from the backward region to the region, including the broadside direction, while references [12][13][14] have a very The comparisons of the previous works and the proposed polarization-recon ble LWA are shown in Table 1. As is demonstrated in Table 1, it is worth noting proposed antenna has a wide scanning angle from the backward region to the f region, including the broadside direction, while references [12][13][14] have a very scanning region.…”

“…As is demonstrated in Table 1, it is worth noting proposed antenna has a wide scanning angle from the backward region to the region, including the broadside direction, while references [12][13][14] have a very The comparisons of the previous works and the proposed polarization-recon ble LWA are shown in Table 1. As is demonstrated in Table 1, it is worth noting proposed antenna has a wide scanning angle from the backward region to the f region, including the broadside direction, while references [12][13][14] have a very scanning region. In addition, compared with references [13,14], the proposed ante As the p-i-n diodes are switched on, the proposed antenna radiates LP beams scanning from −32 • to 41 • , including the broadside direction with the frequency varying.…”

“…Except for the pattern-reconfigurable LWA, the polarization-reconfigurable LWAs were recently reported [12][13][14]. In [12], a 2-D polarization-reconfigurable holographic antenna with broadside radiation was designed, which has linear polarization (LP), righthand circular polarization (RHCP), and left-hand circular polarization (LHCP) by utilizing a polarization-insensitive hologram as the radiating structure and an electrical-control polarization-reconfigurable feeding launcher.…”

“…In [12], a 2-D polarization-reconfigurable holographic antenna with broadside radiation was designed, which has linear polarization (LP), righthand circular polarization (RHCP), and left-hand circular polarization (LHCP) by utilizing a polarization-insensitive hologram as the radiating structure and an electrical-control polarization-reconfigurable feeding launcher. An LWA with RHCP and LHCP was also designed in [13], which is a short-circuited helically slotted circular waveguide antenna. The backward and forward conical radiation for RHCP and LHCP, respectively, are leaked through the helical slit, depending on the handedness of the feed.…”

“…In the reconfigurable LWA area, much attention focuses on the scanning radiation patterns at the fixed frequency. A few works study the polarization-reconfigurable LWA, and these designs [12][13][14] always possess the polarization diversity over a very narrow beam-scanning region or even at a fixed beam angle.…”