Design and Implementation of Fractal Antenna For SWB applications

The miniaturized wideband antennas are used widely in modern communication systems. Fractal geometries can be used to fabricate multi-band and broad-band antennas. One of the main components of super wideband communication systems is a SWB antenna. Applying fractals to the antenna elements allows for smaller size, multiband and broad band properties. The term fractal, which means broken or irregular fragments, each of which having reduced size and copy of the whole. This paper focuses the design and analysis of star triangular fractal antenna. The designed structure offers maximum gain and bandwidth ratio greater than 10:1 for SWB (2.18 to 44.5 GHz) applications. The purpose of the iteration is to reduce the size of the fractal antenna. The proposed antenna has been analysed for the part of SWB band from 1 GHz to 30 GHz. The proposed antenna structure can be designed using design equations and simulated using computer simulation technology (CST). Finally prototype has been developed and parameters are measure using network analyser. The observed results show that the proposed antenna structure can be used for wideband wireless communication applications with minimum loss and excellent radiation.

A compact dual band-notched SWB antenna with high bandwidth dimension ratio

In this research, a compact dual band-notched (DBN) super-wideband (SWB) coplanar waveguide-fed antenna with high bandwidth (BW) dimension ratio of 7427.4 has been presented. The proposed antenna covers a very wide frequency range from 2.8 to 40 GHz (BW ratio of 14.28:1) with |S11|<−10 dB. The overall antenna size is 20 × 14 × 1.6 mm3 which consists of an FR4 substrate with a dielectric constant of 4.4, a shovel-shaped radiating patch and the symmetric stair-shaped ground plane. The DBN characteristics are achieved by employing a pair of C-shaped and circular slots on its shovel-shaped radiating patch to reject the interferences caused by two WiMAX (3.7–4.7 GHz) and WLAN (5.7–6.4 GHz) bands. The notched frequency bands can be controlled by changing the radii of slots. The SWB property of the antenna is obtained by using a symmetric stair-shaped ground plane and also a shovel-shaped radiating patch. The measured results of the fabricated prototype in frequency-and time-domain are also presented and compared with the numerical results. The results indicate that the antenna has good performance over the entire operating BW (173.8%) which makes it very potential candidate for modern SWB applications.

Design and Investigation of Modern UWB-MIMO Antenna with Optimized Isolation

This paper proposes a compact, semi-circular shaped multiple input multiple output (MIMO) antenna design with high isolation and enhanced bandwidth for ultrawide band (UWB) applications. A decoupling stub is used for high isolation reaching up to −55 dB over the entire bandwidth. The proposed antenna is used for UWB as well as super wide band (SWB) applications. The overall size of the proposed antenna is 18 × 36 × 1.6 mm3. The | S 11 | and voltage standing wave ratio (VSWR) of the proposed antenna are less than −10 dB and 2, respectively, in the range of 3–40 GHz. The total impedance bandwidth of the proposed design is 37 GHz. The VSWR, | S 11 | , | S 22 | , | S 21 | , | S 12 | , gain, envelope correlation coefficient (ECC), radiation pattern, and various other characteristic parameters are discussed in detail. The proposed antenna is optimized and simulated in a computer simulation technology (CST) studio, and printed on a FR4 substrate.

Design of SWB MIMO Antenna with Extremely Wideband Isolation

This paper presents a compact planar multiple input multiple output (MIMO) antenna for super wide band (SWB) applications. The presented MIMO antenna comprises two identical patches on the same substrate. Dimensions of the MIMO antenna are 0.17λ × 0.20λ × 0.006λ mm3, with respect to the lowest resonance of 1.30 GHz. The SWB antenna was manufactured using F4B substrate having a dielectric constant of 2.65 that provides a percent impedance bandwidth and bandwidth ratio of 187% and 30.76:1, respectively. The mutual coupling between the antenna elements is suppressed by placing a T-shaped corrugated strip in the mid of two antenna elements. The proposed MIMO antenna exhibits maximum diversity gain of 10 dB, low mutual coupling (<−20 dB), low envelope correlation coefficient (ECC < 0.02), efficiency >80%, and low reflection coefficient (<−10 dB) in the SWB frequency range (1.30 GH–40 GHz). The presented antenna is a good candidate for SWB applications. The designed antenna has been experimentally validated, and the simulated results were also verified.

A Modified Avian Egg Shaped CPW Fed Printed Monopole for SWB Applications

A compact egg-shaped super wide-band patch antenna with coplanar waveguide (CPW) feed is proposed. A much simpler design equation has been identified compared to previous reported works for egg-shaped patch antennas. An optimized egg shaped antenna has been designed and implemented on FR4 substrate with the dimensions 30mm x 27.5mm x 1.6mm.The antenna with geometry modifications has an impedance bandwidth 2.85-31.6 GHz. The performance of the antenna was validated analytically for super wideband (SWB) operation and experimentally for ultra-wideband (UWB) operation. A maximum gain of 4.4dBi and a minimum of 2dBi was observed at 6.5GHz and 3GHz respectively. A 30% reduction in patch area has been achieved compared to existing egg-shaped SWB antennas in literature. The lower frequency bound of the antenna is scalable with dimensions for lesser permittivity substrates which has been analytically validated. It is identified that the proposed antenna design could be used to achieve flexibility in bandwidth. This antenna is a potential candidate for super wideband applications.

A Novel SWB Antenna with Triple Band-Notches Based on Elliptical Slot and Rectangular Split Ring Resonators

In this paper, a wideband antenna was designed for super-wideband (SWB) applications. The proposed antenna was fed with a rectangular tapered microstrip feed line, which operated over a SWB frequency range (1.42 GHz to 50 GHz). The antenna was implemented at a compact size with electrical dimensions of 0.16 λ × 0.27 λ × 0.0047 λ mm3, where λ was with respect to the lowest resonance frequency. The proposed antenna prototype was fabricated on a F4B substrate, which had a permittivity of 2.65 and 1 mm thickness. The SWB antenna exhibited an impedance bandwidth of 189% and a bandwidth ratio of 35.2:1. Additionally, the proposed antenna design exhibited three band notch characteristics that were necessary to eradicate interference from WLAN, WiMAX, and X bands in the SWB range. One notch was achieved by etching an elliptical split ring resonator (ESRR) in the radiator and the other two notches were achieved by placing rectangular split ring resonators close to the signal line. The first notch was tuned by incorporating a varactor diode into the ESRR. The prototype was experimentally validated with, with notch and without notch characteristics for SWB applications. The experimental results showed good agreement with simulated results.