Wideband cavity-backed log-periodic-slot end-fire antenna with vertical polarization for conformal application

Abstract

A 6–18 GHz wideband cavity‐backed log‐periodic‐slot end‐fire antenna with vertical polarization for conformal application is presented. The log‐periodic folded slots and parasitic slots with 10 slot elements are applied to cover 6–18 GHz frequency band and the log‐periodic metallic cavity is placed under each slot element to keep wideband performance and prevent the effects of large metallic carrier on radiation patterns. The ground plane etched with log‐periodic slots is reversed and touched directly to the backed cavity and a dielectric cover is added to the antenna, to further improve the antenna performance. Meanwhile, a broadband microstrip‐coplanar waveguide transition is inserted in the antenna for measurements. With these designs, the proposed antenna shows good impedance matching (|S11|<27 dB) and end‐fire gain (>4 dBi) performances in 6–18 GHz. The proposed antenna also keeps low‐profile and easy flush‐mounted characteristic which is suitable for conformal applications of high speed moving carriers.

Low-Profile Ultra-Broadband Log-Period Monopole End-Fire Antenna

“…It shows that, over the whole 2-13 GHz, the measured peak gain is averaged above 6 dBi. This gain performance is more stable than most of the previously reported end-fire antennas [6][7][8][9][10][11][12][13][14][15][16][17]. Table 1 concludes the 6-18 GHz wideband end-fire antennas reported recently.…”

“…It clearly shows very good end-fire radiation performances with low cross-polarizations at all the frequencies obtained. In the E-plane radiation patterns, a 30-degree titling angle is presented, due to the limited ground plane size [6][7][8][9][10][11][12][13][14][15][16][17].…”

“…In recent years, a wideband and low-profile antenna with an end-fire radiation pattern has attracted much attention because of the high demand in modern wireless communication and radar areas [1][2][3][4][5]. Many high-performance end-fire antennas have been reported, especially the newest designs published in the past several years, like the monocone quasi-Yagi antenna [6,7], log-periodic slot antenna [8], SIW H-plane ridged antenna [9][10][11], Vivaldi antenna [12,13], surface wave antenna [14,15], and low-profile log-period monopole antenna [16,17]. Most of those endfire antennas have realized the ultra-wideband and lowprofile features.…”

Cylindrical conformal array antenna for near field focusing

“…Compared with the aforementioned planar antennas for near‐field focusing, conformal antennas can be easily pasted on the surface of carrier platforms such as aircraft, missiles, and satellites, without damaging the carrier's shape, structure and aerodynamics. In addition, it provides more flexible designs and broadens range of beam scanning 21–25 . In this letter, we use the conformal cylindrical phased array antenna to realize near‐field focusing.…”

“…In addition, it provides more flexible designs and broadens range of beam scanning. [21][22][23][24][25] In this letter, we use the conformal cylindrical phased array antenna to realize near-field focusing. Firstly, theoretical analysis of generating near-field focusing by cylindrical array is given and omnidirectional scanning along circumference of the cylinder with good stability can be obtained.…”