A State-of-the-Art Review on 4D Printed Antennas and Other Adaptable Designs

This article offers a thorough review of the current state-of-the-art in four-dimensional (4D) printed antennas and possible adaptable designs. It provides a succinct examination of various categories of materials used in three-dimensional (3D) and 4D printing, including the utilization of smart materials available in both printable and synthesized forms. The review encompasses a concise analysis of fabrication techniques, stimuli, and response behaviors applied in various types of smart materials. These materials have the potential to fabricate antennas with tunable and reconfigurable properties, including frequency of operation, bandwidth, gain, and radiation pattern. Given the novelty of applying 4D printing in antenna technologies, the review also considers additional reconfigurable antennas with mechanically tunable properties, as well as those in non-printed formats. This exploration hints at potential adaptations to the latter for the development of 4D printed antennas. The utilization of 4D printing presents a complex yet intriguing approach to antenna fabrication, offering the possibility of creating dynamic antennas with sophisticated characteristics.