Mechanically pattern reconfigurable dual‐band antenna with omnidirectional/directional pattern for 2.4/5GHz WLAN application

Abstract

A mechanically pattern reconfigurable dual‐band antenna with an omnidirectional radiation pattern or a directional pattern for 2.4/5GHz dual‐band WLAN application is presented. By manually rotating the top substrate, the antenna can operate at patch state or monopole state, respectively. A novel U‐gap structure consisting of an outer patch, an inner patch and a U‐shaped gap is introduced to achieve the dual band feature at both operation states. The measured overlapped bands of the two states are 2.4–2.56 GHz and 5.22–6 GHz, covering the 2.4–2.48 GHz and most of the 5.15–5.85 GHz WLAN band. The measured peak gain is 2.4 dBi at 2.5GHz, 6.2 dBi at 5.5 GHz for monopole state, and 5.8 dBi at 2.5 GHz, 7.2 dBi at 5.5 GHz for patch state.

Recent Development of Flexible and Stretchable Antennas for Bio-Integrated Electronics

“…The demonstrated examples include monopole, Yagi-Uda, and helical antennas. In a similar idea, rotating the top substrate mechanically reconfigures a dual-band antenna from a patch state (with an omnidirectional radiation pattern) to a monopole state (with a directional pattern) (Figure 5D) [101]. Combining such concept with smart materials such as those responding to external triggers could further enhance the performance of the system.…”

“…( D ) Photograph of fabricated antenna that can be mechanically reconfigured from a patch state to a monopole state. Reproduced from [101]; Copyright 2017, John Wiley and Sons. ( Ei ) Stretchable twisted-pair transmission line inspired by twisted-pair cables.…”

A Pattern-Reversal Wideband Antenna Integrating Metal Rings, Diodes-Loaded Stubs and Defective Ground

“…The first one is to change the structure of the antenna. [1] and [2] mechanically altered the geometry of the antenna to realize pattern tuning. This way will introduce large mechanical errors and is not suitable for the field of miniaturized civil mobile communications.…”

An efficient fractal rectenna for RF energy harvest at 2.45 GHz ISM band

“…Therefore, the antenna with omnidirectional characteristic and stable radiation pattern is preferred to capture more RF energy. [4][5][6] Furthermore, a fractal antenna is a better alternative for a compact potable electronic device. [7][8][9][10] Aside from the antenna, the overall RF to DC conversion efficiency of the rectenna is strongly dependant on the performance of the rectifier.…”

“…In addition, the RF energy in ambient atmosphere may come from any direction due to the unknown angle of incident RF signal and location of signal source. Therefore, the antenna with omnidirectional characteristic and stable radiation pattern is preferred to capture more RF energy . Furthermore, a fractal antenna is a better alternative for a compact potable electronic device .…”