Spidron fractal tapered slot antenna for dual-band radar applications

A dual-broadband Spidron fractal tapered slot antenna is proposed for radar applications in the S and X bands. Dual-Spidron fractal patches are symmetrically arranged adjacent to each other, and a slot is etched from the central section of the patch to form a feeding slot. A microstrip-to-slotline transition is used to excite the tapered aperture of the Spidron fractal patch. The proposed antenna is fabricated and tested, and has compact dimensions of 35.8mmx24mm (0.358(0)x0.24(0)). The measured -10dB reflection bandwidths for the lower and upper frequency bands are 39.42% (2.75-4.10GHz) and 34.74% (7.85-11.15GHz), respectively. The measurements also indicate that the proposed antenna exhibits two types of radiation patterns, namely, a near omni-directional pattern in the lower band and a directional pattern in the upper band. The measured peak gains range from 0.4 to 2.97dBi in the lower band and from 1.42 to 5.52dBi in the upper band.