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Author

Wenquan Che

Bio: Wenquan Che is an academic researcher from South China University of Technology. The author has contributed to research in topics: Wideband & Band-pass filter. The author has an hindex of 37, co-authored 528 publications receiving 5649 citations. Previous affiliations of Wenquan Che include Nanjing University & Southeast University.


Papers
More filters
Journal ArticleDOI
TL;DR: In this article, a dielectric loaded substrate integrated waveguide (SIW) H-plane sectoral horn antenna has been proposed and two antennas with rectangular and elliptical shaped loaded dielectrics were designed and fabricated.
Abstract: A dielectric loaded substrate integrated waveguide (SIW) H-plane sectoral horn antenna has been proposed in this paper. The horn and the loaded dielectric are integrated by using the same single substrate resulting in easy fabrication and low cost. Two antennas with rectangular and elliptical shaped loaded dielectrics were designed and fabricated. These antennas have high gain and narrow beamwidths both in the E-plane and in the H-plane. The results from the simulation and those from the measurement are in good agreement. To demonstrate applications of the array, the small aperture elliptical dielectric loaded antenna has been used to form an array to obtain higher gain and to form a one-dimensional monopulse antenna array.

331 citations

Journal ArticleDOI
TL;DR: In this article, a planar ultrawideband (UWB) antenna with dual notched bands is proposed and investigated, where a T-shaped stub embedded in the square slot of the radiation patch and a pair of U-shaped parasitic strips beside the feed line is used.
Abstract: A novel planar ultrawideband (UWB) antenna with dual notched bands is proposed and investigated. The antenna consists of a square patch and a modified grounded plane. To realize dual notched bands characteristics, a T-shaped stub embedded in the square slot of the radiation patch and a pair of U-shaped parasitic strips beside the feed line is used. The advantage of this antenna is the high rejection level in the stopband. The measured results show that the proposed dual-notched-bands planar antenna shows a very wide bandwidth from 2.8 to 11.0 GHz defined by voltage standing wave ratio VSWR <; 2, with two notched bands of 3.3-4.0 GHz (WiMAX band) and 5.05-5.90 GHz (WLAN band), respectively. Both the experimental and simulated results of the proposed antenna are presented, indicating that the antenna is a good candidate for various UWB applications.

170 citations

Journal ArticleDOI
TL;DR: In this paper, a switchable low-profile broadband frequency rasorber/ absorber based on slot arrays is presented and investigated, which exhibits small insertion loss at the transmission window and a bandwidth around 100%.
Abstract: Switchable low-profile broadband frequency rasorber/ absorber based on slot arrays is presented and investigated. First, an equivalent circuit model is proposed to synthesize a rasorber with the transmission window within the absorption band. Based on the slot arrays, simple design guidelines for rasorber design are further developed. Low-profile broadband rasorber and high-selectivity rasorber are, respectively, designed and analyzed to verify the design strategies. Moreover, by loading the switching diodes, a switchable rasorber/absorber is proposed and analyzed, which exhibits small insertion loss at the transmission window and a bandwidth around 100% while the thickness is less than 10% of the free-space wavelength at the lowest operating frequency. Moreover, one extension of dual-polarized rasorber is also designed and analyzed to further validate the design strategy. For demonstration, the rasorber prototypes are fabricated and measured, good agreement between the simulation and measured results is observed.

156 citations

Journal ArticleDOI
TL;DR: In this paper, two novel wideband differential bandpass filters based on a T-shaped structure are proposed, and two prototypes with 3-dB fractional bandwidth of 70% and 70.7% for the differential mode and insertion loss greater than 13.5 dB for common mode (0-19 GHz).
Abstract: Two novel wideband differential bandpass filters based on a T-shaped structure are proposed in this paper. Broad passband and wideband harmonic suppression for the differential/common mode can be easily achieved for the wideband differential filter without cross coupling, due to the controlled resonator frequencies of the shorted/open T-shaped structure. In addition, another more compact differential filter using cross coupling is proposed with two transmission zeros close to the passband to improve the selectivity for the differential mode. To verify the presented concept, two prototypes (er = 2.65, h = 0.5 mm) with 3-dB fractional bandwidth of 70% and 70.7% for the differential mode and insertion loss greater than 13.5 dB for common mode (0-19 GHz) are designed and fabricated. Good agreement can be observed between measured results and theoretical expectations.

146 citations

Journal ArticleDOI
TL;DR: In this article, the analytical equivalence of the SIW and the RW of the solid wall is established on comparing the surface impedances along the side walls, of the SiW and of an RW through analytical continuation.
Abstract: Rectangular waveguide (RW) with sidewalls of vertical conducting cylinders (i.e. SIW, substrate-integrated waveguide) becomes popular with the advent of low-temperature co-fired ceramic structure; its analysis is usually numerical, or modal, leading to empirical design formulas. However, its analytical equivalence to the common RW of the solidwall is identified; in other words, analytical design formulas of the SIW and the equivalent RW of solid sidewalls are the same. The equivalence is established on comparing the surface impedances along the side walls, of the SIW and of an RW through analytical continuation. The equivalence formulas, propagation and cut off frequency show very good agreement with the results from both numerical simulations and measurements of hardware experiments, and over wide frequencies. The good agreements are easily understood on the basis of the conformal maps and the variational principle.

122 citations


Cited by
More filters
Journal ArticleDOI
TL;DR: In this article, the authors provide an overview of the recent advances in the modelling, design and technological implementation of SIW structures and components, as well as their application in the development of circuits and components operating in the microwave and millimetre wave region.
Abstract: Substrate-integrated waveguide (SIW) technology represents an emerging and very promising candidate for the development of circuits and components operating in the microwave and millimetre-wave region. SIW structures are generally fabricated by using two rows of conducting cylinders or slots embedded in a dielectric substrate that connects two parallel metal plates, and permit the implementation of classical rectangular waveguide components in planar form, along with printed circuitry, active devices and antennas. This study aims to provide an overview of the recent advances in the modelling, design and technological implementation of SIW structures and components.

1,129 citations

ReportDOI
08 Dec 1998
TL;DR: In this article, the authors consider the unique features of UWB technology and propose that the FCC should consider them in considering changes to Part 15 and take into account their unique features for radar and communications uses.
Abstract: In general, Micropower Impulse Radar (MIR) depends on Ultra-Wideband (UWB) transmission systems. UWB technology can supply innovative new systems and products that have an obvious value for radar and communications uses. Important applications include bridge-deck inspection systems, ground penetrating radar, mine detection, and precise distance resolution for such things as liquid level measurement. Most of these UWB inspection and measurement methods have some unique qualities, which need to be pursued. Therefore, in considering changes to Part 15 the FCC needs to take into account the unique features of UWB technology. MIR is applicable to two general types of UWB systems: radar systems and communications systems. Currently LLNL and its licensees are focusing on radar or radar type systems. LLNL is evaluating MIR for specialized communication systems. MIR is a relatively low power technology. Therefore, MIR systems seem to have a low potential for causing harmful interference to other users of the spectrum since the transmitted signal is spread over a wide bandwidth, which results in a relatively low spectral power density.

644 citations

01 Nov 1984
TL;DR: In this article, a substrate-superstrate printed antenna geometry which allows for large antenna gain is presented, asymptotic formulas for gain, beamwidth, and bandwidth are given, and the bandwidth limitation of the method is discussed.
Abstract: Resonance conditions for a substrate-superstrate printed antenna geometry which allow for large antenna gain are presented. Asymptotic formulas for gain, beamwidth, and bandwidth are given, and the bandwidth limitation of the method is discussed. The method is extended to produce narrow patterns about the horizon, and directive patterns at two different angles.

568 citations