Aperture coupled modified rectangular dielectric resonator antenna arrays for X-band applications

Abstract

This paper proposes an aperture coupled 3×3 rectilinear geometry-based periodic modified rectangular dielectric resonator antenna array for X-band applications. In this paper, the complex electromagnetic field problem of RDRA is addressed through a modified rectilinear-shaped DRA. Notches are created on the dielectric resonator to alter the normal components of the electric field pattern instantaneously. It leads to the reduction in the magnitude of reactive current density, resulting in a lessening of the Q-factor and enhancement of the bandwidth. This antenna shows multiband response, resonating at 8.42, 10.08, and 11.60 GHz frequency with a peak gain of 12.94 dBi at 9.75 GHz with consistent gain stability over the entire frequency band of operation. The radiation efficiency is around 96.1% due to low losses. The impedance bandwidths for different bands are 4.51%, 2.77%, and 4.56% at the resonating frequency of 8.42, 10.08, and 11.60 GHz. A comparative analysis of input and output characteristics is carried out between single, double, and nine-cell arrays. The designed antenna is excited by a branch line series-corporate constrained micro-strip feeding network with three apertures. This novel design is suitable for microwave X-band applications.