Design of a Compact Reconfigurable Sierpinski Gasket Fractal Antenna for 5G and Satellite Communications

Reconfigurability is one of the key features of 5G/6G radiofrequency systems. The possibility to adapt the working frequency depending on the application or the status of the nodes is important, especially in Smart Radio Environments. In this regard, the design of antennas operating at different frequency bands is challenging since strict requirements on the footprints and the radiation properties are introduced. Among other geometries, fractals present unique features in terms of small electrical lengths: they have been used for years by researchers to shrink antenna dimensions in a very effective way. An interesting perspective of these antennas is the possibility to switch the working frequency among several bands connecting/disconnecting the fractal cells. The aim of this paper is the design and the optimization of an electrically reconfigurable Sierpinski gasket fractal antenna. Four different states are obtained: in the first the device works at 27 GHz (mmWave), in the second at 16 GHz, in the third at 11 GHz (Ku-band), and in the fourth at 3.5 GHz (Sub-6GHz). The antenna operates efficiently in all the bands of interest.