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 bow-tie 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.
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