We propose a push/pull origami antenna, transformable between a single antenna element and a three-element array. In limited space, the proposed origami antenna can work as a single antenna. When the space is not limited and a higher gain is required, the proposed origami antenna can be transformed to a series antenna array by pulling the frame.
In order to push the antenna array back to a single antenna, the frame for each antenna element size must be different. The frame and supporting dielectric materials are built using a three-dimensional (3D) printer. The conductive patterns are inkjet-printed on paper. Thus, the proposed origami antenna is built using hybrid printing technology. The 10-dB impedance bandwidth is 2.5–2.65 GHz and 2.48–2.62 GHz for the single-antenna and array mode, respectively, and the peak gains in the single-antenna and array mode are 5.8 dBi and 7.6 dBi, respectively. The proposed antenna can be used for wireless remote-sensing applications.
To ensure the stability of the paper on the 3D-printed frames, supporting beams with width W b were built in the first and third antennas. The geometries of the antenna in the single antenna mode and array mode are shown in Figure 1. The frames of all the three elements are shown in Figure 2.
FABRICATION AND MEASUREMENT RESULTS
Copper tape was attached to the bottom side of the 3D-printed dielectric to serve as the antenna ground plane. Conductive silver epoxy (CW2400, Electronics Materials Co., Daejoo, Korea) was used to connect an SMA connector to the microstrip line. The volume resistivity of CW2400 is less than 0.001 Ω·cm; therefore, it has enough conductivity. The final antenna prototypes in the single antenna and array modes are shown in Figure 4.
A push/pull origami antenna that provides the flexibility to be operated both as a single antenna and as a 3 × 1 series array is proposed. The antenna has three elements with different frame sizes. In limited space, the frame of the third antenna element is pushed into the frame of the second antenna element, which is pushed under the first antenna element. In this mode, the antenna operates as a single element antenna.
When the available space for the antenna is not limited and a higher gain is required, the proposed origami antenna can be transformed into a series array by pulling the second and third antenna elements. The proposed origami antenna was built using hybrid printing technology. This type of antenna can play an important role in remote-sensing applications.
Source: Chung-Ang University
Authors: Syed Imran Hussain Shah | Sungjoon Lim