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Abstract-A planar monopole loaded with composite right/left-handed transmission line (CRLH-TL) for broadband LTE mobile phone is presented. The CRLH-TL with a propagation constant of zero is added to widen the input impedance bandwidth of the antenna. The proposed antenna covers the LTE700/2500/GSM850/900/1800/1900/UMTS2100 and WLAN2400 bands. Impedance bandwidths of VSWR < 2.5 (S 11 < −7 dB) ranging from 675 to 1010 MHz and 1690 to 2550 MHz are obtained. The size of the monopole is 60×16×1 mm 3 which is smaller than most of the LTE antennas. Detailed design considerations of the monopole are described. A prototype is fabricated and tested. Both simulated and experimental results are discussed.

In this paper, a triangular facets based, highly accurate, and adaptive finite-difference time-domain (FDTD) mesh generation technique is presented. There are two innovations in the implementation of this technique. One is adaptive mesh lines placement method. The mesh lines are automatically set to be dense where the object has fine structure and sparse where the object has rough structure based on the incremental placement of the triangular mesh vertices. The other is ray column tracing method. Ray columns in the normal direction of the coordinate plane are employed to intersect the surface facets to make the mesh generation results highly accurate. The generating FDTD results of the numerical examples show that the proposed technique can well-restore objects with complex edge structures. The simulation results are in good agreement with the theoretical results.

The MnO x /Al2O3 catalysts with different Ce content doping were prepared by an ultrasonic impregnation method, and the catalytic activity for NO oxidation removal was tested in a fixed-bed quartz tube furnace. Simultaneously, the catalysts were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), full-automatic physical-chemical adsorption instrument, and field emission scanning electron microscope (FESEM) to analyze the effect of Ce addition on the adsorption capacity and catalytic activity. Experimental results validated that the activity of the MnO x /Al2O3 catalyst was greatly promoted with Ce addition. According to the characterization results, it could be concluded that Ce doping led to significant changes in the crystalline phase on the catalyst surface, which increased the relative content of surface lattice oxygen and promoted the catalytic oxidation of NO. By observing the physical properties of the surface and analyzing the surface elements of the catalyst, it could be inferred that a manganese-cerium solid solution was formed on the surface of Mn0.4Ce0.05/Al. Moreover, Ce addition increased the catalyst pore size, which enhanced the adsorption and contact of NO and O2 with the active sites on the catalyst surface, and reduced the resistance of the reactants during internal diffusion. All these variations assigned to Mn0.4Ce0.05/Al were favorable for the catalytic oxidation of NO.

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