公开(公告)号：US5721551A

公开(公告)日：1998-02-24

申请号：US636009

申请日：1996-04-22

申请人： Hung Ban Tran ,  Dennis M. Rubien ,  Pravit Tulyathan

发明人： Hung Ban Tran ,  Dennis M. Rubien ,  Pravit Tulyathan

IPC分类号： H01Q17/00

CPC分类号： H01Q17/00

摘要： An apparatus for attenuating traveling wave reflections from a surface, due to an impedance mismatch between the surface and free space. The apparatus includes a resistive element having an impedance between that of the surface and free space. The resistive element is positionable relative to the surface so as to minimize the impedance mismatch between the surface and free space. The resistive element is preferably a resistively graded element, which includes a forward end with an impedance approaching the impedance of the surface. An aft end of the resistively graded element has a high impedance relative to free space. The aft end is positionable sufficiently distant from the surface so as to minimize any traveling wave reflection due to impedance mismatch between the surface and free space.

摘要翻译： 由于表面和自由空间之间的阻抗不匹配而衰减来自表面的行波反射的装置。 该装置包括在表面和自由空间之间具有阻抗的电阻元件。 电阻元件可相对于表面定位，以便最小化表面和自由空间之间的阻抗失配。 电阻元件优选是电阻渐变元件，其包括具有接近表面阻抗的阻抗的前端。 电阻分级元件的后端相对于自由空间具有高阻抗。 后端可以距离表面足够远，以便由于表面和自由空间之间的阻抗失配而使任何行波反射最小化。

公开(公告)号：US5337016A

公开(公告)日：1994-08-09

申请号：US88024

申请日：1993-07-09

申请人： Sam Wozniak ,  Hung B. Tran ,  Charles A. Newstrom ,  Pravit Tulyathan

发明人： Sam Wozniak ,  Hung B. Tran ,  Charles A. Newstrom ,  Pravit Tulyathan

IPC分类号： G01R27/32 ,  G01S7/40

CPC分类号： G01S7/40 ,  G01R27/32

摘要： A method and apparatus for traveling wave attenuation measurement in the UHF and VHF frequency bands. The test set up comprises a ramp structure located in the quiet zone of a parallel plate set up. The RAM specimen to be tested is attached to the top ramp surface starting at the highest point of the ramp. The time domain signal is gated to reject all scattering except the contribution from the ramp surface. The inverse Fourier transform of the gated time data results in the frequency response of the ramp. The RCS from ramp with RAM material attached is normalized to that of the perfectly conducting surface to provide a relative attenuation of the surface traveling wave.

摘要翻译： 一种用于在UHF和VHF频带中行波衰减测量的方法和装置。 测试装置包括位于平行板安装区域中的斜坡结构。 要测试的RAM样品从斜坡的最高点开始连接到顶部斜坡表面。 时域信号被门控以拒绝所有散射，除了来自斜面的贡献。 门控时间数据的傅立叶逆变换导致斜坡的频率响应。 带有RAM材料的斜坡的RCS被归一化为完美导电表面的RCS，以提供表面行波的相对衰减。