Yunliang Long

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A novel slotted substrate integrated waveguide (SIW) leaky-wave antenna is proposed. This antenna works in the TE<sub>10</sub> mode of the SIW. Leakage is obtained by introducing a periodic set of transverse slots on the top of the SIW, which interrupt the current flow on the top wall. It is seen that three modes (a leaky mode, a proper waveguide mode, and(More)
A new microstrip monopolar patch antenna is proposed and analyzed. The antenna has a wide bandwidth and a monopole like radiation pattern. Such antenna is constructed on a circular patch antenna that is shorted concentrically with a set of conductive vias. The antenna is analyzed using a cavity model. The cavity model analysis not only distinguishes each(More)
The periodic half-width microstrip leaky wave antenna (MLWA) with a backward to forward scanning capability is presented in this paper. The proposed antenna consists of a series of half-width MLWA. The radiating periods place on the different sides of the transmission line. The radiating period works in cutoff region of the first higher order mode, the(More)
A new substrate integrated waveguide (SIW) leaky-wave antenna is investigated for endfire-radiation with a narrow beam and sidelobe suppression. Maximum directivity conditions for endfire-radiation from line sources with different amplitude distributions are theoretically discussed as a design aid. Interestingly, for endfire beams it is seen that designs(More)
Equations are presented for calculating the propagation wavenumbers for half- and full-width microstrip lines operating in the <i>EH</i><sub>1</sub> mode. The transverse resonance method is used for determining the propagation wavenumbers. For the half-width microstrip line, only the self-admittance of the open edge needs to be considered. The(More)
A novel design of a multiband monopole mobile phone antenna with circular polarization for GNSS application is presented. The proposed antenna generates four resonant frequencies with branch lines and a shorted parasitic strip to obtain a wide operating band. With the definition of 2.5:1 VSWR, the bandwidth covers several wireless communication systems,(More)
The two-way split-step parabolic equation (2W-SSPE) method is improved to be able to model both forward- and backward-waves propagation over irregular perfectly electrical conducting (PEC) surfaces and irregular lossy surfaces with impedance boundary conditions (IBC). The discrete mixed Fourier transform (DMFT) is applied in both forward- and backward-(More)
A fourth-order compact symplectic finite-difference time-domain (CS-FDTD) method for modeling long-range propagation is proposed. Theoretical analyses of numerical stability and dispersion are presented, and the comparisons to Fang's high-order FDTD and symplectic FDTD (S-FDTD) method are provided. One-dimensional (1-D) numerical simulation is performed to(More)
The time domain (TD) solution for the multiple diffraction of spherical waves after an arbitrary number of obstacles with different shapes such as knife-edges and wedges, is presented. The proposed TD solution is based on the representation of the inverse Laplace transform of the corresponding frequency domain solution in closed form, as it is given by a(More)
A center-fed circular patch antenna with shorting vias and a coupled annular ring is proposed. With a low-profile configuration, the antenna provides a wide bandwidth by merging three resonant modes, including the TM<sub>02</sub> mode of the circular patch, the TM<sub>01</sub> mode generated by the shorting vias, and the TM<sub>02</sub> mode of the coupled(More)