In this work, a beam‐steering array antenna for pattern stabilisation is presented. The antenna element consists of two layers with a unique structure of microstrip to coplanar waveguide (CPW) transition to cover a frequency range from 20 to 30 GHz and a stable pattern at all operating frequencies. To increase the gain of the antenna element, an elliptical broadband Fabry–Perot cavity structure is used. The element manages 3 dB gain bandwidth of almost 23–26 GHz with a 14.4 dBi peak. In addition, a modified Butler matrix consisting of two 90° and two 135° couplers without phase shift section is used to attain a stable pattern. The proposed Butler matrix performs a stationary phase with a phase error of less than ±6° over a frequency band from 21 to 29 GHz. The integration of the proposed element and feed network leads to a beam‐tilting antenna capable of managing its patterns through the input ports in the operating frequency range of 20–29.5 GHz (9.5 GHz) and 20.6–29.6 GHz (9 GHz) for ports 1 and 2, respectively.

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A wideband antenna is studied in this paper using a multi‐layer metasurface structure and implementing a periodic array for enhancing the gain. The performance of the multilayer antenna is improved by using a sub‐wavelength Fabry‐Perot cavity (FPC). The feeding and main radiation patches of the microstrip antenna are placed separately on two substrates, which are stacked on top of each other without an air‐gap in between. Two other substrates are placed within an optimized distance on top of the microstrip antenna. This structure, which has a double‐sided periodic array configuration, includes a capacitive artificial impedance surface (AIS) on one side, and an inductive partially reflective surface (PRS) on the other side of the substrates. Making use of this configuration increases the gain up to 18 dBi and widens the frequency bandwidth. Moreover, measurement results indicate a frequency range from 10.8 GHz to 15 GHz with an S11 less than −10 dB.

In this work, a novel circularly polarized (CP) Fabry-Perot resonator beamsteering antenna array with capability covering C-band applications is introduced. The proposed antenna array caters to a relatively constant high gain at a broadband impedance bandwidth in comparison with conventional arrays.The presented antenna is designed based on a broadband Butler matrix feeding network which is able to stabilize direction patterns at different frequencies for each of the ports for the sake of phase distribution in whole operation frequency with low phase error.