3D printed reconfigurable helical antenna based on microfluidics and liquid metal alloy

This paper demonstrates a new approach to build 3D reconfigurable antennas at an extremely low cost and the first 3D printed reconfigurable helical antenna based on microfluidics and liquid metal alloy (LMA). With the fused deposition modeling (FDM) 3D printing technique, 3D microfluidic channel can be fabricated in a short production cycle cost-effectively. EGaIn, a non-toxic LMA, is filled into a 3D printed helix channel and form the helical antenna. As the gain of the antenna is determined by the number of turns of the helix which is controlled by the volume of LMA, the gain of the antenna can be tuned when needed. A more than 4 dB gain increase around 5 GHz is measured with the prototype when the number of turns of helix increases from 2 to 8 (0.2 mL LMA volume change), which demonstrates the reconfigurability of the proposed helical antenna.