In this paper, the design method of a quadruple-band rejection ultra-wideband (UWB) antenna with three co-directional complementary split ring resonators (CSRRs) is proposed. Within the design step, individual antennas corresponding to each rejection band is flrst designed, and then a flnalized structure is determined by assembling these individual antennas altogether. The shape of the flnal antenna achieves both the impedance matching of ultra-wideband and the respective resonances at four rejection bands. Here, the mutual coupling among the band rejection elements is minimized, and the placement of the resonators is optimized. The fabricated antenna is compact enough to be integrated into the UWB system, and also the measured results show the validity of the proposed design strategy.

/pdf/design-of-the-ultrawideband-antenna-with-a-quadruple-band-2mg2gcq2fr.pdf

Design of the Ultrawideband Antenna with a Quadruple-Band Rejection Characteristics Using a Combination of the Complementary Split Ring Resonators

In this paper, we present a new ultra wideband antenna design with band rejection for UWB applications. A CPW-fed circular patch radiates through a circular aperture, which ensures wideband impedance matching and stable omnidirectional pattern over an UWB frequency range, from 3GHz to 10.6GHz. In order to avoid interference

/pdf/ultra-wideband-cpw-fed-aperture-antenna-with-wlan-band-3sdcwm6i18.pdf

Ultra wideband cpw-fed aperture antenna with wlan band rejection

A neuro-based approach to designing a Wilkinson power divider

In this paper a novel triple band compact microstrip slot antenna is designed, utilizing fractal Koch shape based on metamaterial electric-LC element coupling load. The antenna is fed by CPW line, and it has triple band resonances operating at frequencies of about 1.5, 3.5 and 5.4 GHz for GPS, WiMAX and WLAN applications. The bandwidth of antenna at aforementioned frequencies is about 1.9%, 14% and 5% with the gains of −4.5, 3.75 and 5.3 dBi respectively. Also it has property of circular polarization for WiMAX application at 3.5 GHz. Furthermore metamaterial ELC element based on the metasurface theory, and making variation of the current distribution for circular polarization, made a compact small antenna at 1.5 GHz, where the antenna size is reduced to λ/5 × λ/5 through coupling on ELC element. The total size of the fractal antenna is assumed 40 × 40 mm, and is designed and fabricated on FR-4. The simulation results are extracted by HFSS commercial software, and compared with experimental results.

Compact microstrip fractal Koch slot antenna with ELC coupling load for triple band application

In this paper, the application of compact non-uniform transmission line transformers (NTLTs) in suppressing and controlling the odd harmonics of the fundamental frequency is presented. A design example showing the complete suppression of the odd harmonics of the fundamental frequency is given. In addition, several compact NTLTs are designed showing the possibility of controlling the existence of a fundamental frequency's odd harmonics. Moreover, multi-band operation using NTLTs is investigated. Speciflcally, a design example of a miniaturized triple-frequency NTLT is introduced. Based on these compact NTLTs, a 3-way triple-frequency modifled Bagley power divider (BPD) with a size reduction of 50%, and a 5-way modifled BPD with harmonics suppression and size reduction of 34%, are designed. For veriflcation purposes, both dividers are simulated using the two full-wave simulators IE3D and HFSS. Moreover, the modifled 5-way BPD with harmonics suppression is fabricated and measured. Both the simulation and measurement results validate the design approach.

/pdf/non-uniform-transmission-line-transformers-and-their-136t8jgwpm.pdf

Non-Uniform Transmission Line Transformers and Their Application in the Design of Compact Multi-Band Bagley Power Dividers with Harmonics Suppression

In this paper, a novel dual-band rectangular slot antenna for wireless local area network (WLAN) applications in IEEE 802.11b/g/a systems is presented. The proposed antenna, fed by a 50› microstrip line, has size of 32mm £ 28mm £ 1:6mm. By introducing a pair of U-shaped strips, the proposed antenna can generate two separate impedance bandwidths. The prototype of the proposed antenna has been successfully constructed and tested. The low-band resonant frequency is located at about 2.4GHz, with i10dB impedance bandwidth from about 2.3 to 2.5GHz. The high- band resonant frequency is located at about 5.7GHz, with i10dB impedance bandwidth from about 4.9 to 6.0GHz. In addition, the measured results show good radiation characteristics at the two operating bands, proving the dual-band operation of the proposed antenna.

https://www.jpier.org/pierl/pierl13/09.09111103.pdf

Design of a novel microstrip-fed dual-band slot antenna for wlan applications

A novel planar out-of-phase (180°) power divider with ultra wideband behavior is presented The proposed power divider employs a T-junction in output ports combined with a slotline and a microstrip line accompanied by wideband microstrip to slotline transitions in order to achieve an out-of-phase signal division over a large frequency range With the help of the metal pin connected to the system ground plane, the impedance bandwidth improved from 85% to about 133% The simulated and measured results show that the proposed power divider has equal power division with high stability of phase, a low insertion loss and good return loss at the three ports across the band 31 GHz to more than 106 GHz

A Novel Planar 180° Out-of-Phase Power Divider for UWB Application

In this paper, a compact dual-frequency three-way unequal power divider is presented. The design of the proposed power divider is accomplished by transforming the length and impedance of each quarter-wave branch into two sections with the characteristic impedance of Z 1 and Z 2, the length of λ/4 and four resistors which provide enough isolation at two frequencies. The configuration of the proposed power divider and formulas used to determine the design parameters are given. To verify the validity of the formulas, a three-way power divider with a power split ratio of 1 : 1.5 : 3 for two frequencies of 915 MHz and 2450 MHz is fabricated and measured. The size of the proposed power divider is about two thirds of that of the conventional one. The measured results show good agreement with the simulated ones. Good experimental performances of the proposed power divider, including an unequal power split, low return loss, and good isolation at the two frequencies between the output ports, are obtained.

A Compact Dual-Frequency Three-Way Unequal Power Divider

In this paper, a printed ultra-wideband (UWB) antenna with dual band-notched characteristics suitable for UWB applications is presented. The proposed antenna, by inserting a pair of line-shaped slots into the radiating patch and adding a pair of C-shaped strips coupled to the microstrip feed line, is designed to realize the dual band-notched characteristics at 3.5 GHz and 5.5 GHz, respectively. Good agreement between the simulated and measured results is obtained, which shows that the proposed antenna has a broad impedance bandwidth ranging from 2.3 to 12.5 GHz with VSWR less than 2.0, except the frequency bands of 3.2–3.8 GHz for WiMAX and 5.0–5.9 GHz for WLAN. Moreover, the nearly omnidirectional radiation patterns and stable gain over the operating frequency band have been obtained, which meet the UWB system requirements.

Design of a Dual Band-Notched Ultra-wideband Antenna

The design and analysis of a printed UWB antenna with multiple band-notched characteristics are presented in this paper The proposed antenna consists of a fork-shaped radiation element on the front side and a modified rectangular slot on the ground plane By inserting three different novel resonating structures (curl slotline, zigzag open stub and C-shaped resonator) in the reference UWB antenna, multiple band-notched characteristics at 24 GHz, 35 GHz, 58 GHz are achieved Good agreement between simulation data and measurement results is obtained And the measured peak gain of the proposed antenna is shown in this paper The results prove that this antenna can be applied to the UWB communication systems to avoid interference with other narrowband wireless systems, such as 24 GHz WLAN, 35 GHz WiMAX, and 58 GHz WLAN The conceptual equivalent circuit models, which are based on the surface current distributions on the resonating structures, are also shown to further analyze the band-notched characteri

J.-G. Gong

Papers

Design of a novel microstrip-fed dual-band slot antenna for wlan applications

A Novel Planar 180° Out-of-Phase Power Divider for UWB Application

A Compact Dual-Frequency Three-Way Unequal Power Divider

Design of a Dual Band-Notched Ultra-wideband Antenna

Design and Analysis of a Printed UWB Antenna with Multiple Band-Notched Characteristics