Wideband and low-profile beam-tilted H-plane horn array based on MMPTE

A wideband and low-profile H-plane horn antenna array is proposed to achieve a tilted-beam in H-plane based on the theory of maximum power transfer efficiency (method of maximum power transfer efficiency (MMPTE)), which is built on bent corrugated substrate integrated waveguide structure. The horn array is implemented in the substrate with the thickness of 0.13 ${\lambda }_0$ at the centre frequency. The arc-shaped aperture is employed to achieve smooth transition from horn aperture to the free space, which also improve the front-to-back ratio of the radiation pattern. In order to realise a tilted-beam, MMPTE is used to obtain the excitation distribution of array elements. A double-layer butler matrix feed network is built based on the calculated excitation, maintaining the characteristic of broadband and miniaturisation simultaneously. Measured VSWR parameter of the proposed antenna is less than 2.0 from 6 to 18 GHz. The antenna achieves a beam titling of ±6° in H-plane. It is observed that the measured results agree well with the simulated ones.