A metamaterial loaded hybrid fractal multiband antenna for wireless applications with frequency band reconfigurability characteristics

Abstract

In the present article authors propose the design and analysis of an octagonal shape multiband metamaterial loaded antenna with implementation of hybrid fractal geometry for wireless applications. Multiband features in the antenna structure is realized by applying the slotted and hybrid fractalization of Moore and Koch curve approach in radiating section along with introduction of two metamaterial SRR cells. The frequency band reconfigurability characteristics in proposed design is achieved by placing the PIN diode inside the connecting strip between the central hybrid fractal geometry and feedline. During forward bias condition of PIN diode antenna structure resonates at hepta (seven) band mode at WiMAX (3.5 GHz)/Lower C-band (4.41 GHz)/WLAN (5.4/5.8 GHz)/Lower X-band (8.26 GHz)/Upper X-band (10.48 GHz)/Lower Ku-band (13.35 GHz)/Middle Ku-band (14.42 GHz) wireless standards with S11 ≤ −10 dB. Proposed antenna represent the hexa and hepta band features during reverse bias (OFF-state) and forward bias condition (ON-state) of PIN diode respectively. A stable and consistent radiation patterns, appropriate impedance matching and an acceptable gain are achieved at all the operating frequencies of the proposed antenna.

Metamaterial-Inspired Electrically Compact Triangular Antennas Loaded with CSRR and 3 × 3 Cross-Slots for 5G Indoor Distributed Antenna Systems

“…Table 2 compares the proposed MTM antenna performance with several other MTM antennas presented in the literature and operating at 3.5 GHz [52][53][54][55][56][57][58]. All MTM antenna sizes and thicknesses in Table 2 are normalized to the free space wavelength λ o at the resonant frequency 3.5 GHz.…”

“…The −10 dB relative bandwidth (BW) of these MTM antennas' results are summarized in the BW column. Table 2 shows that previous MTM antenna designs either improved the bandwidth [52,53] or gain [54][55][56] or reduced the antenna size [56][57][58]. Although, the proposed MTM antenna based on cross-slot results shows a 60 percent reduction in size and a seven-fold increase in the bandwidth over the conventional MPA design at 3.5 GHz.…”

Compact ACS‐fed frequency reconfigurable octa‐band antenna for wireless portable systems

“…However, despite being reconfigurable, these antennas 20–33 have large dimensions and only a few operational bands, which restricts their applications in contemporary RF front‐ends where there is limited space for the antennas. Additionally, a few of these antennas 20–33 used numerous bias lines, lumped components, and more PIN diodes to tune the operating states, which complicated the antenna structure and created additional integration and cost challenges.…”

“…A compact frequency reconfigurable monopole antenna utilizing two PIN diodes is reported in Reference 23. In Reference 24, a frequency‐reconfigurable multiband fractal antenna loaded with metamaterial is proposed. A low‐profile frequency agile quad‐band antenna employing varactor diodes is reported in Reference 25.…”

“…A frequency reconfigurable inverted-F shape antenna with capacitors and PIN diodes is proposed in Reference 32, and a frequency reconfigurable multiband slot antenna is proposed in Reference 33. However, despite being reconfigurable, these antennas [20][21][22][23][24][25][26][27][28][29][30][31][32][33] have large dimensions and only a few operational bands, which restricts their applications in contemporary RF front-ends where there is limited space for the antennas. Additionally, a few of these antennas [20][21][22][23][24][25][26][27][28][29][30][31][32][33] used numerous bias lines, lumped components, and more PIN diodes to tune the operating states, which complicated the antenna structure and created additional integration and cost challenges.…”