公开(公告)号：US4413254A

公开(公告)日：1983-11-01

申请号：US299304

申请日：1981-09-04

申请人： George G. Pinneo ,  Jon N. Weaver

发明人： George G. Pinneo ,  Jon N. Weaver

IPC分类号： G01S13/82 ,  G01S13/04 ,  G08B13/24

CPC分类号： G08B13/2422 ,  G08B13/2437 ,  G08B13/2448 ,  G08B13/2471 ,  G08B13/2474

摘要： A surveillance marker has a semiconductor connected between arms of a dipole antenna, one arm being of non-ferrous conductive material and the other of high permeability low coercivity material such as permalloy. Higher coercivity magnetizable pieces are disposed adjacent the low coercivity arm, and all is sandwiched between paper or other insulating layers. The marker is detected by a combination of RF field and low frequency magnetic field generating and receiving units that energize a master alarm only when both units simultaneously detect the marker signals. Magnetizing the higher coercivity pieces suppresses a signal that would otherwise be reradiated by the marker from the high permeability arm thereby rendering the marker undetectable.

摘要翻译： 监视标记具有连接在偶极天线的臂之间的半导体，一个臂由有色金属导电材料连接，另一个连接在高磁导率低矫顽力材料如坡莫合金之间。 高矫顽力可磁化片靠近低矫顽力臂设置，全部夹在纸或其他绝缘层之间。 通过RF场和低频磁场产生和接收单元的组合来检测标记，仅在两个单元同时检测标记信号时激励主报警。 磁化较高的矫顽力片段抑制了否则将会被标记物从高磁导率臂重新辐射的信号，从而使标记物不可检测。

公开(公告)号：US4352098A

公开(公告)日：1982-09-28

申请号：US150461

申请日：1980-05-16

申请人： James H. Stephen ,  John D. McCann ,  Michael A. Flemming

发明人： James H. Stephen ,  John D. McCann ,  Michael A. Flemming

IPC分类号： G01S13/82 ,  G08B13/24 ,  G08B13/14

CPC分类号： G08B13/2422 ,  G08B13/2431 ,  G08B13/2477

摘要： A surveillance system transmits a microwave carrier signal through a surveillance zone (14). Two low frequency energy fields are also established in the zone being produced by respective pairs of closely spaced apart low frequency signals radiated from opposite sides of the zone. A receptor reradiator in the zones receives these signals and reradiates a reply signal to a receiver the reply signal consisting of the microwave carrier signal amplitude modulated in accordance with the instantaneous value of the low frequency fields at the location of the receptor reradiator. The receiver separates out preselected intermodulation products and activates an alarm only when the preselected intermodulation products are present.

摘要翻译： 监视系统通过监视区（14）发送微波载波信号。 在由区域的相对侧辐射的相应的彼此间隔开的低频信号对中产生的区域中也建立了两个低频能量场。 区域中的受体再辐射器接收这些信号，并且向接收机再发送响应信号，该响应信号由根据受体再辐射器位置处的低频场的瞬时值幅度调制的微波载波信号组成。 接收器分离预选的互调产物，并且只有当预选的互调产物存在时才激活报警。

公开(公告)号：US4274089A

公开(公告)日：1981-06-16

申请号：US41225

申请日：1979-05-21

申请人： Terence G. Giles

发明人： Terence G. Giles

IPC分类号： G08B13/22 ,  G01V3/00 ,  G01V3/10 ,  G01V3/12 ,  G01V15/00 ,  G08B13/24

CPC分类号： G08B13/2414 ,  G01V15/00 ,  G08B13/2417 ,  G08B13/2422 ,  G08B13/2431 ,  G08B13/2477

摘要： A merchandise security system in which a signal having a first frequency is generated and is multiplied or divided by n to provide a signal having a second frequency which is transmitted. A responder circuit in a tag on the merchandise divides or multiplies the transmitted signal by n and transmits it to a receiver where it is compared with the originally generated first frequency and is used to produce an alarm signal.

摘要翻译： 一种商品安全系统，其中生成具有第一频率的信号并将其乘以或除以n以提供具有发送的第二频率的信号。 商品中的标签中的应答器电路将发送的信号乘以n并将其发送到与原始产生的第一频率进行比较的接收机，并用于产生报警信号。

公开(公告)号：US4160209A

公开(公告)日：1979-07-03

申请号：US812133

申请日：1977-07-01

申请人： Thomas F. Thompson

发明人： Thomas F. Thompson

IPC分类号： G08B13/24 ,  H04B5/00 ,  H04B1/59 ,  H04B7/145

CPC分类号： G08B13/2488 ,  G08B13/2422

摘要： A method and apparatus using a single-frequency oscillator as a source for resonating, selectively, an infinite number of different higher-frequency resonant circuits. The oscillator signal is clipped, and this clipped signal is processed in an infinitely adjustable amplifier to change the slopes of leading and trailing edges thereof. The amplifier also functions to cause these modified edges to extend over a predetermined signal-level range.

公开(公告)号：US4087802A

公开(公告)日：1978-05-02

申请号：US689336

申请日：1976-05-24

申请人： Robert D. Williamson

发明人： Robert D. Williamson

IPC分类号： G08B13/24 ,  G08B13/22

CPC分类号： G08B13/2422 ,  G08B13/2471

摘要： A high frequency generator projects an electronic wave into a control zone under surveillance to establish a first field. A frequency modulated (FM) generator is used for establishing a second field throughout the zone. A third field of the same FM carrier frequency, but with a different modulation, is established only at extreme ends of the control zone to define the limits of the control zone. Presence only within the control zone of a transponder causes the reradiation of a signal comprised of the FM signal and the high frequency signal, which in turn activates an alarm circuit.

摘要翻译： 高频发生器将电子波投入监控区域，建立第一个领域。 调频（FM）发生器用于在整个区域建立第二场。 相同FM载波频率的第三个场，但是具有不同的调制，仅在控制区的最末端被建立，以限定控制区的限制。 仅在应答器的控制区域内存在导致由FM信号和高频信号组成的信号的再辐射，其再次激活报警电路。

公开(公告)号：US3798642A

公开(公告)日：1974-03-19

申请号：US3798642D

申请日：1972-09-27

申请人： MICROLAB FXR

发明人： AUGENBLICK H ,  ENGLE W

IPC分类号： G01S13/75 ,  G06K7/10 ,  G06K19/067 ,  G08B13/24 ,  G01S9/56

CPC分类号： G08B13/2422 ,  G01S13/753 ,  G06K7/10009 ,  G06K19/0672 ,  G08B13/2431 ,  G08B13/2454 ,  G08B13/2471 ,  G08B13/2477

摘要： A recognition system comprising a transmitter for radiating an amplitude modulated signal to a target that generates a harmonic of the received signal, detects the amplitude modulating signal and modulates the harmonic signal with the detected signal. The target contains a frequency selective network that produces a coded arrangement of signal components which comprise the signal returned by the target. A receiver detects the coded arrangement of signal components.

摘要翻译： 一种识别系统，包括：发射机，用于向生成接收信号的谐波的目标辐射幅度调制信号，检测振幅调制信号并用所检测的信号调制谐波信号。 目标包含频率选择网络，其产生包括由目标返回的信号的信号分量的编码布置。 接收机检测信号分量的编码布置。