A Novel Coplanar Antenna Butterfly Structure for Portable Communication Devices: A Compact Antenna With Multioperating Bands

This article presents a novel antenna design that consists of a butterfly-shaped radiator, the ground, and the slot between them. A lumped element of resistance was inserted between the ground and the radiator plates to enhance the impedance bandwidth of the antenna. The value of the lumped element and the feeding position was carefully selected to achieve the triple-wide operating bands. The lower operating band (0.75-3 GHz) can support radio-frequency identification (RFID), 3G, GPS, wireless local area network (WLAN) (IEEE 802.11b and IEEE 802.11g), WiMax (IEEE 802.16a), and industrial, scientific and medical (ISM) communications. The second band (4.7-5.95 GHz) is suitable for WLAN (IEEE 802.11a), WiMax (IEEE 802.16d), ISM, and 5G applications, whereas the upper band (7.9-8.6 GHz) can support satellite communications (C-band). The compact size of the antenna (20 x 20 x 0.8 mm3), low profile, acceptable values of gain and efficiency, and omnidirectional pattern in the H-plane make the butterfly antenna suitable for many portable communication devices.