Abstract-In this paper, the higher order hierarchical basis functions are employed to solve the electric field integral equation for computing electromagnetic scattering from three-dimension bodies comprising both conducting and dielectric objects. In higher-order methods of moments (HO-MoM), the equivalent surface electric and magnetic currents are usually expanded by the same basis functions, which are not appropriate in our problem here. The pointwise orthogonal basis functions respectively for electric and magnetic currents are proposed in our improved HO-MoM. Quadrilateral patches are used in curvilinear geometry modeling since they result in the lowest number of unknowns. Numerical solution procedure is particularly analyzed, and numerical results are given for various structures and compared with other available data lastly.

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By means of 34.5 GHz millimeter-wave (MMW) sintering, BaO-Nd2O3-TiO2 microwave ceramic dielectric was prepared from nano-particles of the xBaO×(0.35-x)Nd2O3×0.65TiO2 ternary compound, which possess fine grain, low porosity and good dielectric characteristics. The materials which have ultra-low dielectric loss can be fired by MMW heating at very high frequency, which is unable to be done by normal microwave heating at 2.45 GHz. The sintering temperature is 160 ~ 400°C lower than that of normal firing. The ceramic sample consists of the main phase of Nd2Ti2O7 with perovskite-like layer structure (PLS) and the secondary phase of BaNd2Ti4O12 (Ba4.5Nd9Ti18O54)with perovskite-like tungsten bronze structure, being the same as the results from normal sintering. The excellent microwave characteristics were observed.

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