Miniaturised low-profile super-wideband Koch snowflake fractal monopole slot antenna with improved BW and stabilised radiation pattern

摘要

This communication explores the super-wideband Koch snowflake fractal monopole slot antenna for different wireless/multiband applications. The antenna comprises of a modified star-shaped patch, a 50 O triangular tapered feedline, a partial slot loaded ground plane and an I-shaped parasitic element located beneath the radiating element. The self-similarity and space-filling features of Koch iteration technique have been employed at the triangular patch to acquire the antenna compactness and broadband performances. Further by placing a pair of symmetrical L-shaped slots and an inverted U-shaped slot in the ground plane, a super-wide-impedance bandwidth (BW) (S11 < -10 dB) of 650 MHz-20 GHz with a ratio BW of 30.7: 7 is attained. The proposed antenna has a compact size of 17 x 29 x 0.787 mm3 and has a stable radiation pattern over the entire frequency spectrum. For pattern stability, an I-shaped parasitic element was utilised. Moreover, the typical antenna parameters such as return loss, gain, radiation pattern and group delay have been simulated and verified experimentally. Timedomain characteristics have also been studied.