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本文阐述了智能天线的概念.波束形成方法.分析了智能天线在TD-SCDMA系统中的应用以及使用它的有关问题。 相似文献
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Focusing properties of Gaussian beam induced by nonspiral and spiral phase plates are investigated numerically. The nonspiral phase plate introduces phase singularity to the incident beam, and the spiral one adjusts the radial phase distribution. Intensity distributions in geometrical focal plane show that the parameters of phase plates can alter the intensity distributions considerably. And local dark focal spots may be obtained, the focal spot may evolve into a circle, a two-peak spot, or a curve line, which indicates that the combination of nonspiral and spiral phase plates can be used to form novel focal spots. 相似文献
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The effect of an apodizer with two parallel taper refractive surfaces is theoretically investigated for highdensity optical storage. The apodizer may modulate an incident Gaussian beam into an annular beam. Simulation shows that with the increasing inner radius of the modulated beam, the focal spot shrinks obviously. The depolarization effect gets strong simultaneously, which induces the circular symmetry loss of the focal spot. In this process, pattern density of the orthogonal and longitudinal diffractive fields increases remarkably. 相似文献
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梯度折射率纤维透镜玻璃的研究 总被引:1,自引:0,他引:1
本文对发散型和聚焦型两种纤维透镜玻璃的配方设计、熔制以及离子交换工艺进行了研究。从玻璃结构观点出发,就离子交换问题进行了讨论,最后给出自聚焦面阵的研制结果。 相似文献
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制导光纤强度的依赖关系 总被引:1,自引:0,他引:1
分析研究制导高强度光纤强度8个方面的依赖关系,指出光纤强度降低的关键原因是光纤中存在着缺陷即表面微裂纹。因此,必须从制造工艺、制造环境入手,严格控制减少微裂纹方能制造出过2%筛选应变的高强度光纤。 相似文献