Size Reduction of Low Frequency Micro Strip Patch Antennas with Koch Fractal Slots

The development of communication engineering with integration technology demands size reduction of low frequency antennas as an important design perspective. In this work, a microstrip patch antenna with Koch shaped fractal slots implemented with a foam substrate (εr = 1.02) is shown to bring a size reduction of about 84 % compared to an ordinary microstrip patch antenna for the same resonant frequency. However size reduction comes at the cost of gain which is then enhanced to a good level by using 4element array of the same antenna structure as an element reducing the size reduction to 33 %. A 2-element array is then designed to achieve good gain as well as appreciable size reduction of 66 %.