Design of patch antennas and thinned array of patches in a Fabry-Perot Cavity covered by a partially reflective surface

Abstract

Antennas with large gain are obtained here with one or few radiators. The main idea consists of inserting simple radiating elements, as patches, inside a Fabry-Perot Cavity (FPC) resonator. This consists of a ground plane covered by a partially reflecting surface (PRS). We provide here some simple rules for the design of such systems, paying attention to a) the required bandwidth and gain, and b) the equivalent model of the periodic surface that forms the PRS, with the goal of designing large antenna gain by using arrays with thinned number of elements. In the present investigation we obtain 19 dB gain with a 2x2 array with a bandwidth of 3.6%.

Array Antenna With Increased Element Separation Based on a Fabry–PÉrot Resonant Cavity With AMC Walls

“…A further study confirmed that the same limit also applies to a FPC antenna based on a metallic PRS [11]. Returning to our discussion on the proposed antenna, an analysis of the simulations results, mentioned earlier, suggested that the use of vertical AMC walls increases the maximum array source separation distance from 1.5 to approximately (to be exact, it is 1.98 or 160 mm).…”

“…The AMC walls are introduced both on the sides and in the center of the structure, in order to improve the amplitude and phase distribution of fields within the cavity. This leads to a reduction of the sidelobe level and an increase of directivity, which enables one to increase the separation distance between the two radiating elements beyond the previously observed limit (1.5 [9]- [11]). Simulations have been carried out in order to determine this optimum separation distance and to compare the antenna performance against the case without AMC walls as well as the case with PEC walls.…”

“…In this way, it was possible to create a sparse array with low sidelobes [9]- [11]. Furthermore, a study into the performance of compact FPC antennas, excited by a single radiation source, employed PEC and AMC sidewalls along the -plane boundaries, in order to improve the aperture efficiency [12].…”