Realization of Electrically Small, Low-Profile Quasi-Isotropic Antenna Using 3D Printing Technology

Abstract

A 3D printed, low-profile, electrically small antenna with a quasi-isotropic radiation pattern is presented herein. It is composed of an electric meandered dipole antenna, and the extended arcs from the meander line mimicking the current flow of the loop antenna. A quasi-isotropic radiation pattern is achieved from the total current flow over the proposed structure. Modern stereolithographic 3D printing and nano-polycrystalline copper coating technologies are used to build a prototype. The measured antenna exhibits a good uniformity in terms of the radiation pattern with a maximum gain deviation of 4.5 dB at 959 MHz and a radiation efficiency of 81 %, close to the computed expectations. The electrical size of the antenna ka is 0.48, and its height is λ 0 /82.32.INDEX TERMS 3D printing, isotropic radiation pattern, electrically small antennas, radiation pattern synthesis.

Design of an Electrically Small, Planar Quasi-Isotropic Antenna for Enhancement of Wireless Link Reliability under NLOS Channels

“…The design parameters are also listed. The antenna is composed of a small meander dipole and arcs extended from each end of the dipole as in [18]. The arc at the top of the substrate rotates in a counterclockwise direction, while the arc at the bottom rotates in a clockwise direction, and they form a small loop together.…”

“…The quasi-isotropic radiation pattern can be generated by the pattern synthesis of small dipoles such that the null point of one dipole is along the maximum-field direction of the other dipole, consequently minimizing the blind spots of each dipole. Cross-placement, proper wrapping of electric dipoles, or a combination of small electric and magnetic dipoles are common approaches [14][15][16][17][18][19][20]. The reported antennae designed under this principle show a measured gain deviation from 2.6 to 12.9 dB over the entire space [16][17][18][19][20][21][22][23][24][25].…”

“…Cross-placement, proper wrapping of electric dipoles, or a combination of small electric and magnetic dipoles are common approaches [14][15][16][17][18][19][20]. The reported antennae designed under this principle show a measured gain deviation from 2.6 to 12.9 dB over the entire space [16][17][18][19][20][21][22][23][24][25]. They are either in a volumetric or planar form.…”

The Use of 3D Printing Technology for Manufacturing Metal Antennas in the 5G/IoT Context

“…Although a microstrip patch antenna and a pyramidal horn antenna were correctly built with Electrifi [ 24 ], respectively for the operating frequencies of 2.5 GHz and 5.8 GHz, there are some challenges in the production of RF devices for higher frequencies using this type of material. In [ 25 , 26 , 27 ] three different antennas were developed using Electrifi filament with conductive properties, an electric meandered dipole antenna, a 3D-printed dipole, and a 3D-printed conformal patch antenna, for 915 MHz, 900 MHz, and 2.32 GHz respectively.…”

Electrically Equivalent Model Design of a Ku-Band Helical Antenna Matching Section for Ease of 3D Printing Technology Use

“…뿐만 아니라, 스프레이 코팅 등의 도금 과정을 통해 얻어 지는 도전율은 구리 덩어리(bulk copper)에 비해 20배 정 도 낮고 [6] , 선택적 도금 역시 절연 부분에 대한 마스킹과 같은 추가 작업으로 인해 제작 시간이 길어지는 경향이 있다. 이와 같은 상황에서 3차원 구조 안테나의 임피던스 및 방사 특성을 유지하며, 그 형상을 선택적 도금에 적합 하도록 변형한 연구 결과 또한 발표된 바 있다 [9] .…”