Yong-Chang Jiao

A Novel Microstrip Rectangular-Patch/Ring- Combination Reflectarray Element and Its Application

In this letter, a novel single-layer microstrip reflectarray element composed of a rectangular patch and a rectangular ring is presented. Ansoft HFSS and CST Microwave Studio, two different kinds of electromagnetic simulation softwares, are used to analyze the reflect phase for the designed element. To validate the proposed design and evaluate its performances, a parametric study is carried out. For the optimal parametrics, the proposed structure offers a slope value of 40deg/mm, while the phase range is in excess of 450deg. Then, a prime-focus 45-element microstrip reflectarray with the proposed element is designed and measured. The highest measured gain is about 20 dBi with 1 dBi drop within 30% bandwidth at the center frequency of 10 GHz.

A Three-Fed Microstrip Antenna for Wideband Circular Polarization

New design of a circular microstrip antenna with three feeds for wideband circular polarization is presented. Detailed theoretical analysis proves that a circular microstrip antenna, which is excited by three central symmetrical feeds with equal amplitudes and relative 120° phase shifts, can obtain good circular polarization characteristic. A broadband 120° phase shifter is developed using the metamaterial transmission line (MM TL). It consists of a Wilkinson power divider and three phase-adjusting TLs, namely a MM TL and two microstrips. The antenna is composed of two circular patches. The primary radiating patch under the parasitic patch is excited by three feeds. The proposed antenna can provide an impedance bandwidth of 54.75% and a 3-dB axial ratio bandwidth of 47.88%. The 3-dB gain bandwidth is as large as 40%, with the peak gain 8.8 dBic. In addition, the measured and simulated symmetrical radiation patterns are in good agreement.

Design of a Multiband Quasi-Yagi-Type Antenna With CPW-to-CPS Transition

A novel coplanar waveguide-fed planar quasi-Yagi antenna for multiband operation is presented in this letter. The antenna consists of a basic quasi-Yagi element and a coplanar-waveguide-to-coplanar-strip (CPW-to-CPS) transition, which can excite the odd-mode electric fields at the CPS line though the CPW feed line. The proposed antenna can be used in multiband operation with directional radiation patterns whose front-to-back ratios approximate to 10 dB for desired bands. Its impedance bandwidth, determined by -10-dB reflection coefficient, covers numbers of present wireless communication systems, and the antenna can be simply integrated with other circuit components for its planar structure. Experimental data obtained from a laboratory prototype are also presented. The experimental results confirm the good performances observed by the electromagnetic simulations.

Design of Novel Wideband Monopole Antenna with a Tunable Notched-Band for 2.4 GHz WLAN and UWB Applications

In this article, a novel wideband planar monopole antenna for applications in 2.4GHz WLAN and UWB bands is presented and investigated. The proposed antenna is composed of a gourd-like radiation element fed by a 50Ohm microstrip line and a step-shaped ground plane. A pair of slot lines is etched symmetrically on the ground plane to obtain the 5GHz band-notched characteristic, and the notched band can be tuned. The proposed antenna is successfully simulated, designed, and measured. The measured results agree reasonably with the simulated ones. According to the measured results, the proposed antenna yields a wide bandwidth ranging from 2.2 to 11GHz for VSWR less than 2, except the notched band of 5.1{6.2GHz for 5GHz WLAN. Moreover, it exhibits nearly omnidirectional radiation patterns, stable gain, and small group delay variation across the operation band, which meets the requirements of 2.4GHz WLAN and UWB applications.

Study on High Gain Patch Antenna with Metamaterial Cover

A new method to improve the gain of patch antenna with metamaterial composed of ring aperture lattice is presented. A comparison between the conventional patch antenna and the new metamaterial patch antenna is given. The experimental results show that this method is effective and metamaterial structure can realize congregating the radiation energy, so the gain of the antenna with metamaterial can greatly increase compared with the conventional one.

PRINTED BLUETOOTH AND UWB ANTENNA WITH DUAL BAND-NOTCHED FUNCTIONS

A novel hybrid design of Bluetooth and UWB antenna with dual band-notched functions is proposed. The proposed antenna structure consists of a microstrip-fed main patch and electromagnetically coupled parasitic patch with arc-shaped strips, achieving Bluetooth and UWB performance. Additionally, the split ring resonator (SRR) slot etched on the main patch and the square patch close to microstrip feedline are aimed to obtain dual notched bands. The numerical and experimental results exhibit that the designed antenna operates over the wide frequency band from 3 to more than 12GHz, while showing the extra resonant mode at 2.4-GHz Bluetooth and the band rejection performance at 3.5-GHz WiMAX and 5.2-GHz WLAN.

Compact Ultra-Wideband Monopole Antenna with Novel Filter

—In this article, a compact ultra-wideband (UWB) monopole antenna with a novel filter fed by coplanar waveguide (CPW) is proposed. The 5.5 GHz band-notched characteristic is obtained by introducing a filter composed of a rectangular metal patch and several via holes. There is hardly any change in the current distribution over UWB frequency band except the 5.5 GHz notched band. By adjusting the dimension of the rectangular metal patch, a wanted notched band can be achieved. The corresponding conceptual circuit model is built and discussed. Moreover, good radiation patterns, gains and group delay in the operating band have been obtained.

Design and Experiment on Substrate Integrated Waveguide Resonant Slot Array Antenna at Ku-Band

By transferring the conventional waveguide resonant slot array antenna to the substrate integrated waveguide (SIW) structure, The resonant slot array antenna can take the advantages of the SIW such as small size, low profile, low cost. The whole antenna is fabricated on a single substrate, the design process and experimental results of a five-slot SIW array antenna at Ku-band are presented.

Design of a compact dual-band printed monopole antenna for WLAN applications

A compact dual-band printed monopole antenna is presented in this article. The proposed antenna consists of a rectangular ring monopole and a T-shaped monopole for dual-band operation. The monopole antenna can excite resonances at 2.46 GHz and 5.5 GHz with impedance bandwidths of 16.7% and 24.4% respectively. The proposed antenna has an overall size of 37mm×25mm×1.6mm and can cover all the 2.4/5.2/5.8 GHz WLAN bands. Moreover, good radiation patterns and stable gains within the operating bands have been obtained. Details of experimental results are presented and discussed in this article.

Design and Optimization of a Compact Patch Antenna

A compact patch antenna with limited length is designed in this paper. Design method combining modified particle swarm optimization with Zelands IE3D is used to optimize the bandwidth of the compact antenna. A 75 MHz bandwidth is achieved for the compact patch antenna, and an 8.8 dBi gain is obtained. The optimized compact patch antenna has been fabricated and measured. Good agreement is observed between numerical and experimental results of the compact patch antenna.