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公开(公告)号：US5132699A
公开(公告)日：1992-07-21
申请号：US615963
申请日：1990-11-19
IPC分类号： H01Q1/08
CPC分类号： H01Q1/081
摘要： Provided is a collapsible antenna formed of one or more generally planar and vertically inclined inflatable panels. According to the invention, each of the panels has a continuous outer wall, a continuous inner wall and a plurality of web partitions extending between the inner and outer walls to form a series of tubular members. The inner wall of the collapsible antenna is at least partially covered by a metallic material and a plurality of dipole elements are affixed to the web partitions and spaced from the inner wall in a predetermined relationship such that the antenna will operate at a preselected frequency when inflated.
摘要翻译： 提供了由一个或多个大致平面和垂直倾斜的可充气面板形成的可折叠天线。 根据本发明，每个面板具有连续的外壁，连续的内壁和在内壁和外壁之间延伸以形成一系列管状构件的多个腹板隔板。 可折叠天线的内壁至少部分地被金属材料覆盖，并且多个偶极子元件被固定到幅材隔板上并且以预定关系与内壁间隔开，使得天线将在充气时以预选频率工作 。
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公开(公告)号：US4698634A
公开(公告)日：1987-10-06
申请号：US753695
申请日：1985-07-10
CPC分类号： G01V3/12 , G01S13/0209 , G01S7/292 , G01S13/885
摘要： A radar system for subsurface inspection comprising a short pulse transmitter, an antenna for radiating signals to and receiving external reflections from the surface and from below the surface being inspected, a receiver connected to the antenna for generating an output signal in response to the external reflections, and a clutter cancellation circuit for eliminating internal reflections developed in the system to prevent interference by such internal reflections with the desired external reflections to enhance the system detection capability and reliability of evaluation of such external reflections. Clutter cancellation is accomplished by storing the internally generated clutter and subsequently subtracting it from each incoming radar range sweep consisting of surface and subsurface signals plus unwanted clutter. An internal signal recognition circuit rejects all return signals except that generated internally to the radar by the antenna structure, and this internal antenna echo is used as an internal reference signal whereby the radar system is relatively insensitive to wide variations in external reflection characteristics caused by wide variations in the nature of materials present in the surface being inspected. This in turn provides for a reliable control of the receiver sampling process which is indpendent of external signals and of their amplitude variations. A circuit for compensating for thermal drift permits long term cancellation of the internally generated clutter. The drift compensation circuit, the internal signal recognition circuit and the receiver provide a closed loop stabilization to allow the internal clutter to remain correlated on a range sweep by range sweep basis.
摘要翻译： 一种用于地下检查的雷达系统，包括短脉冲发射器，用于向所述表面和正下方正在被检查的表面辐射信号并接收外部反射的天线，连接到天线的接收器，用于响应于外部反射而产生输出信号 以及用于消除系统中产生的内部反射的杂波消除电路，以防止具有期望的外部反射的这种内部反射的干扰，以增强系统检测能力和这种外部反射的评估的可靠性。 通过存储内部产生的杂波并随后从包括表面和地下信号加上不想要的杂波的每个入射雷达范围扫描中减去杂波消除来实现杂波消除。 内部信号识别电路拒绝所有返回信号，除了由天线结构在雷达内部产生的返回信号，并且将该内部天线回波用作内部参考信号，由此雷达系统对由宽广的引起的外部反射特性的宽变化相对不敏感 存在于被检查表面的材料性质的变化。 这进一步提供对外部信号和它们的幅度变化是独立的接收机采样过程的可靠控制。 用于补偿热漂移的电路允许长期消除内部产生的杂波。 漂移补偿电路，内部信号识别电路和接收器提供闭环稳定，以允许内部杂波在范围扫描范围扫描的基础上保持相关。
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公开(公告)号：US4072942A
公开(公告)日：1978-02-07
申请号：US741312
申请日：1976-11-11
申请人： Anthony V. Alongi
发明人： Anthony V. Alongi
CPC分类号： G01S13/18 , G01S13/003
摘要： Apparatus for the detection of buried objects comprising a broadband, high resolution short pulse transmitter and a bistatic or monostatic noncontacting antenna for radiating the transmitted signal through the ground for reflection from a buried object, a sampling type receiver which reduces the bandwidth and center frequency of the received signal, and a locking circuit controlled by the first reflection from the ground or soil surface to thereby lock the range sweep to the soil surface and eliminate the effects of antenna height variations.
摘要翻译： 用于检测包括宽带，高分辨率短脉冲发射机和双稳态或单稳态非接触天线的掩埋物体的装置，用于通过地面辐射发射的信号以从掩埋物体反射;采样型接收机，其降低带宽和中心频率 接收到的信号和由地面或土壤表面的第一次反射控制的锁定电路，从而将范围扫描锁定到土壤表面，并消除天线高度变化的影响。
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