CPW Fed Wideband Bowtie Slot Antenna on Pet Substrate

Abstract

In this article, a new wideband bowtie shaped slot antenna is realized on a flexible polyethylene terephthalate (PET). The slotted bowtie design is implemented with an asymmetric bowtie flare angle and a larger feeding neck with a metal strip inside the bowtie slot to achieve a wider bandwidth and a higher gain. The designed free space antenna is fabricated using inkjet printing and tested. The fabricated antenna operates over 2.1-4.35 GHz frequency range (69.77% fractional bandwidth) which covers WLAN, WiMax, and most of the 3G and 4G frequency bands. Further, the antenna exhibits an omnidirectional radiation pattern with a peak gain of 6.3 dBi at 4.35 GHz. The bending test of the fabricated device reveals adequate flexibility without significant antenna performance degradation. Moreover, the antenna tunability for any mounting structure application is also investigated by simulating another version of the parent antenna (free space antenna) for drywall mounting applications. The tuned antenna covers a similar frequency band as a free space antenna maintaining the desired radiation performances. The compact size, higher bandwidth, omnidirectional pattern with a higher peak gain and flexible properties make the antenna design suitable for mounting structure for Internet of Things (IoT) applications.

Flexible Antennas: A Review

“…They are popular and attractive in recent years for flexible electronics due to their robustness, flexibility, wettability, and stretchability. Due to high T g, polyimide is one of the most preferred materials for flexible antennas, which had been used as a substrate in prior studies [ 54 , 55 , 56 , 57 , 58 , 59 , 60 , 61 , 62 ]. Sanusi et al [ 55 ] reported on the design and performance of an artificial magnetic conductor (AMC)-backed dipole antenna on Kapton Polymiode for RF energy harvesting in the context of next-generation blood irradiation systems.…”

“…Etching or printing slots on the flexible substrate is another way to manipulate the characteristics of the flexible antenna. [ 61 , 197 , 198 ] showed the compact, flexible antenna with slots in the patch. In another study [ 199 ], Sierpinski carpet fractal antenna on Hilbert slot pattern ground was introduced.…”

“…An implantable ring-slot antenna in the ISM frequency band was proposed using the grounded metamaterial technique in [ 61 ]. This antenna was validated inside the human tissue-mimicking gel and a chicken tissue sample.…”

Fully Flexible, Polymer based Microwave Devices Part I: Materials, Fabrication Technique, and Application to Transmission Lines

“…The antenna's performance and bending effects will be discussed in part II of this work [38]. Many materials that are used in the "flexible" electronics can be considered flexible only with extremely small thicknesses (around 100um), e.g., polyimide (Kapton) [39], polyethylene [40], PTFE [41], and others [42], [7], [43]. To show the fair flexibility our polymer-based microwave devices, the substrate thickness is 3mm in all cases.…”

Fully Flexible, Polymer based Microwave Devices Part II: Flexible Antennas and Performance Evaluation

“…The substrate thickness is 3mm in all cases, which illustrates the flexibility with relatively high substrate thicknesses. Many materials that are used in the "flexible" electronics can be considered flexible only with minimal thicknesses (around 100um), e.g., polyimide (Kapton) [20], polyethylene [21], PTFE [22], and others [23], [7], [24].…”