Wideband Low-RCS Step-Type Cavity-Backed Stacked Dielectric Resonator Antenna for Unmanned Aerial Vehicle Communications

This letter explains the design of a cavity-backed stacked dielectric resonator antenna (SDRA) with wider impedance bandwidth (IBW) and improved gain for
S
-band and
C
-band applications. The antenna mainly comprises of four dielectric resonators stacked above one another of varying size and shape. Combining the SDRA with step-type cavity and conformal radome forms the final antenna. The antenna provides a wider IBW of 103% (2.07–6.55 GHz) and dual-band axial ratio bandwidth of 27.90% (2.38–3.15 GHz) and 16% (5.01–5.88 GHz), respectively. The antenna provides a maximum gain of 9 dBi. The final cavity-backed antenna offers good radar cross-sectional reduction ranging from 2 to 8 GHz for both normal and oblique incidence angles. Hence, the proposed SDRA with the dual-layer cavity is applicable for unmanned aerial vehicle communications.