A novel coplanar waveguide (CPW)-fed compact ultrawideband (UWB) microstrip antenna is proposed for ultrawideband applications. The proposed antenna posseses a method to minimize the monopole antenna by loading of inverted L-strip over the conventional monopole patch antenna to lower the height of the antenna. The ground was vertically extended toward two sides of the single radiator. Therefore, the large space around the radiator that is usually wasted can be effectively saved. The antenna is practically fabricated and simulated. Measured results show a good agreement with simulated results. The prototype with overall size of $25 \times 25 \times 1.6\ {\hbox{mm}}^3$ achieves good impedance matching, constant gain, stable radiation patterns, and constant group delay over an operating bandwidth of 2.6-13.04 GHz (10.44 GHz).

A CPW-Fed Compact UWB Microstrip Antenna

This paper presents the design of a compact split ring resonator (SRR) loaded coplanar waveguide (CPW) fed ultrawideband circular monopole antenna having frequency notch characteristics. The electromagnetic coupling of the SRR with the CPW yields the frequency notch. Fabricated prototypes were measured and compared with simulations and good agreement was obtained. The impedance and radiation plots confirm the suppression of the desired notch frequency. A theoretical formulation to calculate the notch frequency is also proposed and validated.

Compact SRR loaded UWB circular monopole antenna with frequency notch characteristics

Development And modification of materials to build cost-effective Anodes for microbial fuel cells (MFCs): An overview

This letter presents the design of a compact dual-split-ring-resonator (SRR)-loaded coplanar waveguide (CPW)- fed ultrawideband circular monopole antenna exhibiting dual frequency notch and wideband notch characteristics. The SRR pairs are inductively coupled to the radiator and loaded on the back side of the CPW line. Fabricated prototypes were measured and compared to simulations, and good agreement was obtained.

Compact Dual-SRR-Loaded UWB Monopole Antenna With Dual Frequency and Wideband Notch Characteristics

A compact printed microstrip-fed monopole ultrawideband antenna with triple notched bands is presented and analyzed in detail. A straight, open-ended quarter-wavelength slot is etched in the radiating patch to create the first notched band in 3.3-3.7 GHz for the WiMAX system. In addition, three semicircular half-wavelength slots are cut in the radiating patch to generate the second and third notched bands in 5.15-5.825 GHz for WLAN and 7.25-7.75 GHz for downlink of X-band satellite communication systems. Surface current distributions and transmission line models are used to analyze the effect of these slots. The antenna is successfully fabricated and measured, showing broad band matched impedance and good omnidirectional radiation pattern. The designed antenna has a compact size of 25 × 29 mm2.

Design and Analysis of Compact Printed Triple Band-Notched UWB Antenna

A very compact coplanar waveguide (CPW)-fed ultrawideband (UWB) printed monopole antenna (PMA) with triple band-notched characteristics is presented. The antenna uses three open-ended quarter-wavelength slots to create triple band-notched characteristics in 3.3-3.7 GHz for WiMAX, 5.15-5.825 GHz for WLAN, and 7.25-7.75 GHz for downlink of X-band satellite communication systems, respectively. The open-ended quarter-wavelength slot is analyzed in detail. Surface current distributions are used to show the effect of these slots. The antenna shows broad bandwidth and good omnidirectional radiation patterns in the passband, with a very compact size of 19 × 24 mm2.

Very Compact Printed Triple Band-Notched UWB Antenna With Quarter-Wavelength Slots

A disposable water-activated paper-based MFC using dry E. coli biofilm

Enhancing the performance of E. coli-powered MFCs by using porous 3D anodes based on coconut activated carbon

Titanium dioxide powder (TDP) and nickel-doped titanium dioxide powder (NiTDP) were synthesized by simple processes based on the sol–gel method. Nickel can be doped into titanium dioxide to narrow its energy bandgap; as a result, the visible-light photoactivity can be improved. In this study, the particle size of the fabricated TDP and NiTDP were larger than 100 nm, which is suitable for fabricating the light scattering layer (LSL) of the photoanode of dye-sensitized solar cells (DSSCs). The photoanode of our DSSCs comprised two layers: (1) a light absorbent layer made of commercial P25 titanium dioxide nanoparticles and (2) an LSL made of TDP or NiTDP. The DSSC used an organic MK-2 dye sensitizer, iodine-based redox electrolyte, and a multiwalled carbon nanotube counter electrode. Experimental results show that the photocurrent was significantly enhanced when the LSL was used. The DSSC with the absence of the LSL exhibited a conversion efficiency of 2.15%, while those of the DSSCs with the TDP-based LSL and NiTDP-based LSL were 2.37% and 2.78%, respectively. These results combined with UV–Vis spectra data, confirm the effectiveness of the extended visible-light photoactivity of the NiTDP-based LSL on the performance of the photoanode.

Dang Trang Nguyen

Papers

Very Compact Printed Triple Band-Notched UWB Antenna With Quarter-Wavelength Slots

A disposable water-activated paper-based MFC using dry E. coli biofilm

Enhancing the performance of E. coli-powered MFCs by using porous 3D anodes based on coconut activated carbon

Enhancing DSSC Photoanode Performance by Using Ni-Doped TiO 2 to Fabricate Scattering Layers

A floating microbial fuel cell: Generating electricity from Japanese rice washing wastewater