Abstract: A shielded antenna system is provided for reading from and/or writing to an RFID transponder wherein the RF energy radiated from the antenna system has a narrow beam width so that only one RFID transponder in a record member along a web of record members is read from and/or written to without affecting or being affected by any other RFID transponder along the web. It is preferred to provide shielding that enables more energy to be radiated in the upstream direction from the antenna than in the downstream direction from the antenna to provide for earlier reading and/or writing to the transponder in the moving web. The shielding is selectively configured and/or positionable to narrow or broaden the RF energy field of the antenna.

Abstract: A shielded antenna system is provided for reading from and/or writing to an RFID transponder wherein the energy radiated from the antenna system has a narrow beam width so that only one RFID transponder in a record member along a web of record members, each having an RFID transponder, is read from and/or written to without affecting or being affected by any other RFID transponder along the web.

Abstract: A shielded antenna system is provided for reading from and/or writing to an RFID transponder wherein the RF energy radiated from the antenna system has a narrow beam width so that only one RFID transponder in a record member along a web of record members is read from and/or written to without affecting or being affected by any other RFID transponder along the web. It is preferred to provide shielding that enables more energy to be radiated in the upstream direction from the antenna than in the downstream direction from the antenna to provide for earlier reading and/or writing to the transponder in the moving web. The shielding is selectively configured and/or positionable to narrow or broaden the RF energy field of the antenna.

Abstract: A shielded antenna system is provided for reading from and/or writing to an RFID transponder wherein the energy radiated from the antenna system has a narrow beam width so that only one RFID transponder in a record member along a web of record members, each having an RFID transponder, is read from and/or written to without affecting or being affected by any other RFID transponder along the web.

Abstract: A shielded antenna system is provided for reading from and/or writing to an RFID transponder wherein the energy radiated from the antenna system has a narrow beam width so that only one RFID transponder in a record member along a web of record members, each having an RFID transponder, is read from and/or written to without affecting or being affected by any other RFID transponder along the web.

Abstract: A shielded antenna system is provided for reading from and/or writing to an RFID transponder wherein the energy radiated from the antenna system has a narrow beam width so that only one RFID transponder in a record member along a web of record members, each having an RFID transponder, is read from and/or written to without affecting or being affected by any other RFID transponder along the web.

Abstract: A shielded antenna system is provided for reading from and/or writing to an RFID transponder wherein the energy radiated from the antenna system has a narrow beam width so that only one RFID transponder in a record member along a web of record members, each having an RFID transponder, is read from and/or written to without affecting or being affected by any other RFID transponder along the web.

Abstract: A shielded antenna system is provided for reading from and/or writing to an RFID transponder wherein the energy radiated from the antenna system has a narrow beam width so that only one RFID transponder in a record member along a web of record members, each having an RFID transponder, is read from and/or written to without affecting or being affected by any other RFID transponder along the web.

Abstract: A shielded antenna system is provided for reading from and/or writing to an RFID transponder wherein the energy radiated from the antenna system has a narrow beam width so that only one RFID transponder in a record member along a web of record members, each having an RFID transponder, is read from and/or written to without affecting or being affected by any other RFID transponder along the web.

Abstract: A directional coupler sensor is provided for measuring the moisture content of a substrate, such as hair. The sensor incorporates a high frequency directional coupler having a pair of generally parallel plates defining a coupling gap therebetween. A high frequency signal generator generates an electromagnetic field across the gap with the substrate placed across the coupling gap. The coupled power relates to the moisture content of the substrate. A pressure sensor is provided to ensure that the desired compactness of the substrate across the coupling gap is achieved to obtain accurate, reliable and consistent results.

Abstract: A personnel monitoring apparatus has a transmitter for transmitting a data encoded signal. A strap is provided for coupling the transmitter to a person to be monitored. An emitter is attached to the transmitter for emitting an optical signal. A detector is attached to the transmitter for detecting the optical signal. An optical fiber is incorporated with the strap for optically coupling the emitter and the detector. A comparator compares the optical signal and a reference signal, and the result of the comparison sets the value of a preselected data bit in the data encoded signal.

Abstract: A tamper-indicating transmitter is disclosed that indicates a subsequent tamper event during a tamper alert period, T, which is initiated by a first tamper event. In a preferred embodiment, the transmitter includes a transmitter housing having a conductive strap attached thereto for securing the transmitter about a confinee's limb, the confinee typically participating in a home arrest program. Within the housing, a clock source generates pulses having a period t that are input to a counter whose reset line is connected to the conductive strap. When the conductive strap is opened, the counter is held reset and its output is a predetermined multiple bit maximum. Upon the closing of the strap, the counter counts the clock pulses and decrements the counter output from the initial predetermined maximum count down to a predetermined minimum count which remains on the counter output if no subsequent opening of the strap occurs.

Abstract: A transmitter secured to the body of the confinee is provided with tamper detection means such as a conductive mounting strap, which if broken, sets a resettable electronic latch whose output determines the status of a tamper signal receivable by a remote station located within the confinement area. The latch is connected to a timer which serves to automatically reset the latch a first interval of time after it is initially set thereby eliminating the need for external reset equipment to carry out the reset operation. In order to avoid subterfuge, said first time interval is selected to be longer than any continuous interval of time the confinee is permitted to be absent from the confinement area. Information relating to the status of the tamper signal may also be relayed to a central monitoring station.