Investigation of dual-mode cloaked cylindrical slot antennas with a pulsed radar signal processing

In this paper, the cloaked slot antennas (CSAs) in a circular conducting cylinder have been proposed, numerically studied, and fundamentally characterized with respect to the pulsed radar aspects. The two cylindrically slotted antennas have been introduced, namely the axially slotted cloaked antenna and the circumferentially slotted cloaked antenna (CSCA). These two cloaked slot antennas have been parametrically studied to explore the antenna’s resonant characteristics together with their cloaking performance. The resonant frequency of the antennas is controlled by the parameters of the aperture of the slot such as width and length, while independently cloaking the CSAs at the cloaking frequency controlled by the parameters of the coated metasurface. The characteristics of the dual-mode operation at resonant and cloaking frequencies have been intensively studied by pulsed radar signal processing. The modulated Gaussian pulse with the modulation frequency being either resonant or cloaking frequency is used as an excitation source. Several scenarios have been proposed and studied to characterize the cloaking performance and communication capacity of the cloaked slot antennas. The radiating pulse from the CSAs has been numerically characterized by a pulse radar signal processing with an interval of 22.5° in terms of the theta and phi polarizations. These two CSAs have directive and omnidirectional characteristics in the theta- and phi-polarization, respectively.