Super-wideband Characteristics Research Articles

A Compact SWB Monopole Antenna and FSS for Gain Enhancement

In this research, a compact super-wideband monopole antenna is introduced. The antenna's electrical dimensions are 0.228λ × 0.144λ × 0.009λ, the λ represents the wavelength of the lowest operating frequency. The suggested antenna achieves a single operating band 10 dB between 2.8 and 40 GHz, a percentage bandwidth of 173.83%, and a BW ratio greater than 10:1. The suggested super wideband antenna has a large BDR of 5432.18 and a maximum gain of 6.6 dB. The antenna features a U-shaped radiating element and a rectangular, chamferedcornered partial ground plane to attain super wideband characteristics. The antenna has been designed to be compact and flat in structure while still providing adequate gain and a broad range of frequencies, which makes it suitable for a variety of uses in contemporary wireless communication. To increase the antenna, gain for ultrawideband applications, an FSS is developed. The FSS has a compact unit cell with physical dimensions of 18 x 18 mm2 . When the FSS is used as a substrate, the antenna reaches a maximum realized gain of 10 dB. Additionally, at UWB frequencies, a gain amendment of up to 4.61 dB is observed.

Binomial stub loaded compact Vivaldi antenna for superwideband applications

AbstractA compact antipodal Vivaldi antenna with superwideband characteristics is presented in this paper. For improved matching of input impedance at lower frequency region, techniques like binomial tapering of outer edges, binomial slit loaded outer edge, and protruded binomial tapered stub loading have been adopted. The antenna operates in a wide frequency range from 2 to 20 GHz. Experimental results show, stable radiation pattern with peak realized gain of more than 8 dBi, group delay within 1 ns, 164% fractional bandwidth, radiation efficiency of more than 90%, which are in good agreement with the simulated results. The compact size of the proposed antenna (1.14λ0 × 1.21λ0) with wide frequency bandwidth and directional radiation characteristics make it suitable for through-wall radar and medical imaging applications.

Design and Analysis of MIMO Antenna with High Isolation and Dual Notched Band Characteristics for Wireless Applications

A very compact Superwideband multiple-input–multiple-output antenna with dual notched band characteristics is presented. Superwideband characteristics is obtained by means of radiating patch and high isolation between two input ports are obtained by using T-shaped stub in ground plane. Two rejection bands (wireless interoperability for microwave access (WiMAX)/C-band and wireless local area network) are obtained by etching two elliptical slots on radiating patch. Antenna offers large measured useable bandwidth of 2.60–20.04 GHz. Diversity performance is studied in terms of envelope correlation coefficient, diversity gain and total active reflection coefficient. Antenna also offers desirable radiation pattern, gain and radiation efficiency which makes proposed antenna quite suitable for different wireless applications.

Super wideband characteristics of monopolar patch antenna

A simple method of acquiring super wideband characteristics for monopolar patch antenna is proposed. Through adopting a modified cone as feeding and radiating structure, the monopolar patch antenna can reach the impedance bandwidth of more than 1:23.4 for voltage standing wave ratio (VSWR) ≤ 2. In the whole operating band, the antenna has the like-monopole omnidirectional radiation patterns and the peak gains of 3.8–8.7 dB. Meanwhile, the height of the antenna is just 0.074λ c, and the diameter of the radiated body is 0.205λ c, which is smaller than other ultra-wideband omnidirectional antenna.

A Study on Design and Fabrication of Complex Type EM Wave Absorber with Super Wide-band Characteristics

In order to construct an Anechoic Chamber satisfying international standards for EMI testing, it has been recognized that the absorption characteristics of the EM wave absorber must be higher than 20 dB over the frequency band from 30 MHz to 18 GHz. In this paper, an EM wave absorber with super wide-band frequency characteristics was proposed and designed in order to satisfy the above requirements by using the Equivalent Material Constant Method(EMCM) and Finite Difference Time Domain(FDTD). The proposed absorber is to attach a pyramidal absorber onto a hemisphere-type absorber on a cutting cone-shaped ferrite. As a result, the proposed absorber has absorption characteristics higher than 20 dB over the frequency band from 30 MHz to more than 20 GHz.