An Efficient Slotted Waveguide Antenna System Integrated with Inside-Grooves and Modified Gaussian Slot Distribution

Abstract

In this work, an efficient slotted waveguide antenna (SWA) system is designed for S-band high power microwave (HPM) applications. The designed SWA comprises of 10-slot elements placed on the broad wall of SWA with a modified Gaussian distribution (MGD), integrated with two inside-grooves and a Gaussian dielectric radome of high-density polyethylene (HDPE) material. The inside-grooves are introduced to suppress the surface current on the waveguide, which results in high gain as well as sidelobe level (SLL) reduction in the E-plane. The MGD controls the SLLs, and the unique Gaussian profile shape radome offers constant radiation characteristics. The proposed antenna system, within existing size constraints, offers a high gain of 20.1 dBi in conjunction with a high-power handling capability of greater than 100 MW. The designed SWA system has compact dimensions of 8.46λ0× 1.38λ0× 1.50λ0, with SLLs of −20 dB and −22 dB in the H- and E-plane, respectively. The HPM antenna system, radiating at 3 GHz, is fabricated on aluminium material using the milling process. The simulated SWA system has good agreement with measured results. Moreover, the proposed SWA system offers clear advantages in terms of its robustness, design simplicity, high power handling capability, and high gain.

Design, Analysis and Fabrication of an Inside-Grooved Slotted Waveguide Array Antenna for HPM Applications

“…In this section, the single element inside grooved-based slotted waveguide antenna has been analyzed. The detailed design of grooved structure in SWA and its associated parameters including Gaussian profile, its importance in surface current suppression is studied by our group and presented in [13] wherein, it has been established that the use of a Gaussian shaped dielectric radome improves the power handling capability as well as the directivity of SWA.…”

“…5. The depth of the groove on wall of the waveguide is about 0.23 λ 0 with 0.04 λ 0 and 8.17 Table 3 [13]. The slots have round edges to avoid electric field concentration and local scattering.…”

“…These are the critical issues in the design of a phased array antenna with large beam steering requirements [7]. The unwanted MC among the array elements is overcome by using different techniques including but not limited to inter-element spacing, metal wall integration, frequency selective surfaces, metamaterial structures, and grooved regions [12], [13], [14]. Finding an optimum slot spacing eliminates nulls and grating lobes, and is considered a challenging task in the design of an HPM phased array antenna.…”

“…A 10-slot based rectangular SWA configuration integrated with non-periodic grooves and dielectric radome is reported in [13]. The integration of one-dimensional corrugated grooves re-radiate the EM waves to the targeted direction by properly optimizing the period, width, position, and depth.…”