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介绍了一种在传统方形切角微带元上加PBG结构的微带天线。在辐射元的四周刻蚀了等间距的方型贴片,并在中心过孔与地板短路,形成高阻抗表面(HIGP)。仿真和实测结果表明,通过在方形切角微带元四周加高阻抗表面(HIGP)结构,能使天线在不改变园极化特性的基础上,有效地改善天线的前后比,提高天线的增益并有效减少天线的尺寸。 相似文献
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Focusing on the issue to deal with inadequate extraction of metallogenic information especially geological information, a
new method of extracting metallogenic information based on field model, i.e. the field analysis method of metallogenic information,
was proposed. In addition, a case study by using the method of the extraction of metallogenic information from the west Guangxi
and southeast Yunnan district as an example was performed. The representation method for the field models of metallogenic
information, including the metallogenic influence field model and the metallogenic distance field model, was discussed by
introducing the concept of the field theory, based on the characteristic analysis of the distance gradualness and the influence
superposition of metallogenic information. According to the field theory superposition principle and the spatial distance
analysis method, the mathematical models for the metallogenic influence field and the metallogenic distance field of point,
line and area geological bodies were derived out by using parameter equation and calculus. Based on the metallogenic background
analysis, the metallogenic information field models of synsedimentary faults and manganese sedimentary basins were built.
The relationship between the metallogenic information fields and the manganese mineralization distribution was also investigated
by using the method of metallogenic information field analysis. The instance study indicates that the proposed method of metallogenic
information field analysis is valid and useful for extracting the ore-controlling information of synsedimentary faults and
manganese sedimentary basins in the study area, with which the extraction results are significant both statistically and geologically. 相似文献
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设计了一种十字交叉耦合型结构的左手材料,左手材料构成的超宽带陷波滤波器通带范围为3.16~11.84GHz,陷波范围为7.01~8.56GHz。针对现有平面天线设计难、体积大和滤波性能低等问题,将左手材料的滤波器加载于两款结构简单、易于加工的平面天线上,构成基于左手材料的超宽带滤波天线。相比于现有平面天线,该滤波天线同时具有辐射和滤波功能。经HFSS软件仿真和计算得出该滤波天线工作在超宽带范围内,X波段陷波处回波损耗可达-1.30dB,实现了超宽带天线集成化、小型化的设计。 相似文献
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对己内酰胺循环冷却水的水质稳定与处理以及不停车清洗、预膜等新技术的应用进行了介绍,对冷却水碱性处理的腐蚀、结垢、微生物的控制进行了重点研讨。 相似文献