A new high-directivity fractal antenna based on the Modified Koch Snowflake geometry

A high-directivity microstrip antenna based on the modified Koch Snowflake geometry is presented in this paper. The antenna achieves high-directivity behavior owing to the Fractino-Mode current-density localizations or active regions exhibited by boundary fractal microstrip antennas. The antenna geometry is based on the third-iteration Koch Snowflake and has been modified by introducing a fractal-shaped slot. The presence of this slot is responsible for initiating and sustaining a second level of active regions, in addition to those already existing around the patch boundary. Due to the presence of two levels of active regions, the Modified Koch antenna exhibits an increased directivity and improved sidelobe-level behavior compared to the previously reported high-directivity Koch-Fractal antenna. A peak directivity of 14.15dB has been achieved. The antenna has been fabricated and tested. Simulated and measured results have shown a good level of agreement.