This article basically deals with the implementation of a negligible resistance varactor with a wide capacitance value into a modified version of a cedar shape antenna [1]. The electromagnetic characteristics of the antenna are manipulated both at the level of fractal geometry and electrical length using diodes. The antenna achieves tunability in a wide frequency range as a quad band antenna operating between 1.45 GHz and 4.6 GHz when 3 pairs of varactors are connected across slots. Pin diodes are also implemented leading to tunability in triple frequency bands between 3.7 GHz and 5.8 GHz. Moreover, implementing pin diodes as switches allows frequency reconfigurability of a dual band between 2.5 and 4 GHz and a single band of 6.6 GHz. The antenna RF frequencies have many applications in wireless communication that cover GPS, Bluetooth, WIFI, WIMAX and WLAN.
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18. https://www.digikey.com/product-detail/en/skyworks-solutions-inc/SMP1322 079LF/863-1100-1- ND/2052232),.
19. H.-N. https://www.digikey.com/product-detail/en/toshiba-semiconductor-and storage/1SV325,.