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：US4302846A

公开(公告)日：1981-11-24

申请号：US899422

申请日：1978-04-24

申请人： James H. Stephen ,  John D. McCann

发明人： James H. Stephen ,  John D. McCann

IPC分类号： G08B13/24

CPC分类号： G08B13/2422 ,  G08B13/2431 ,  G08B13/2471 ,  G08B13/2477

摘要： This invention is directed to a receptor reradiator for use in a system for detecting the position of the receptor reradiator in a surveillance zone. It comprises a first aerial means for receiving the first signal, second aerial means for radiating said reply signal and a non-linear element coupling the first and second aerial means.

摘要翻译： 本发明涉及一种用于在监视区域中检测受体再辐射器的位置的系统中的受体再辐射器。 它包括用于接收第一信号的第一天线装置，用于辐射所述应答信号的第二天线装置和耦合第一和第二天线装置的非线性元件。

公开(公告)号：US5144312A

公开(公告)日：1992-09-01

申请号：US553253

申请日：1990-07-09

申请人： John D. McCann

发明人： John D. McCann

IPC分类号： G01S5/02 ,  G01S13/87

CPC分类号： G01S13/878

摘要： A system for locating a transponder (10) to an accuracy of plus or minus about 10 m in an area about 5 km across includes a master station (12) and two slave stations (14, 16) at known positions. The transponder and the two slaves each incorporates an electronic flywheel circuit and means to bring it into synchronism with a synchronizing signal from the master station. After a preset delay the transponder then transmits a radio signal to be received by the slave stations and by the master station, the time of receipt of which is measured at each. From these times the location of the transponder (10) is determined by a computer (18).

公开(公告)号：US4303910A

公开(公告)日：1981-12-01

申请号：US899773

申请日：1978-04-25

申请人： John D. McCann

发明人： John D. McCann

IPC分类号： G08B13/24 ,  G08B13/14

CPC分类号： G08B13/2422 ,  G08B13/2431 ,  G08B13/2471 ,  G08B13/2477

摘要： A system for monitoring the position of a receptor reradiator in a surveillance zone having a first means for transmitting a first signal through the zone, and a receptor reradiator operable in response to reception of said signal to radiate at least one reply signal which is a function of the first signal and of the position of said receptor reradiator in the zone. There is also a receiver for receiving the reply signal, means controlled by the receiver, dependent upon the reply signal to indicate the position of the receptor reradiator in the zone, and an alarm triggerable by the receiver responsive to the latter for receiving the reply signals.

摘要翻译： 一种用于监视受监护区域的位置的系统，该监视区域具有用于传送第一信号通过该区域的第一装置，以及受体再辐射器，其响应于所述信号的接收而可操作以辐射至少一个作为功能的应答信号 的第一信号和所述受体再辐射器在该区域中的位置。 还有一个用于接收应答信号的接收机，由接收机控制的装置，取决于应答信号，以指示该区域中的受体再辐射器的位置，以及接收器可触发的报警器，响应于后者用于接收应答信号 。