Abstract: A mechanical interface (84) for a PDA (80) allows the PDA to be positioned in an operative relationship relative to an electronic lock or electronic lockbox (82). The mechanical interface allows the PDA to be used as a key (80) to actuate the lock, by transmitting signals from the PDA to the lock. The PDA retains its normal functionality as a general purpose computer, and the interface can also form part of a link between the PDA and a remote computer (88) and/or database (92).

Abstract: One or more lock or key units of a secure entry system is equipped with a radio receiver. The receiver permits a memory in the lock or key unit to be updated with new data that is modulated onto a radio frequency signal. By this technique, system-wide changes of programming data, such as changes of lockout lists and access codes, and changes targeted to specific units, such as disabling a particular key, can be implemented simply and quickly.

Abstract: One or more lock or key units of a secure entry system is equipped with a radio receiver. The receiver permits a memory in the lock or key unit to be updated with new data that is modulated onto a radio frequency signal. By this technique, system-wide changes of programming data, such as changes of lockout lists and access codes, and changes targeted to specific units, such as disabling a particular key, can be implemented simply and quickly.

Abstract: A key for accessing an electronic lock that also has an optical scanner includes a user interface, first and second memories and a shared data transfer circuit. The first memory serves to store access data detailing identities of locks accessed by the key. The second memory stores data scanned by the scanner. The access data and the scanned data can both be downloaded from the key via the shared data transfer circuit.

Abstract: The position of a radio frequency identification (RFID) transponder may be determined with respect to a plurality of stationary sensors located in an array within certain physical areas. Each sensor comprises a plurality of antenna coils arranged in unique physical orientations and capable of transmitting radio frequency signals of differing phase. The RFID transponder includes an antenna which receives the plurality of signals generated by the antenna coils, and compares the phase of at least two of the signals to determine the relative position of the transponder. The location of the transponder with respect to two or more sensor(s) may also be determined through measurement of the intensity of the signals received by the antenna coil of the transponder. The system and method may also transmit data between a sensor and a dormant (motionless) RFID transponder using a hand-held high intensity RF probe.

Abstract: A system and method for determining the position of a radio frequency identification (RFID) transponder with respect to a sensor. In one embodiment, the system comprises a plurality of stationary sensors located in an array within certain physical areas. Each sensor comprises a plurality of antenna coils arranged in unique physical orientations and capable of transmitting radio frequency signals of differing phase. The RFID transponder includes an antenna which receives the plurality of signals generated by the antenna coils, and compares the phase of at least two of the signals to determine the relative position of the transponder. In a second aspect of the invention, the aforementioned antenna coils emit two direction finding mode (DFM) signals in succession; the first signal with all antenna coils turned on, the second with one of the coils turned off.

Abstract: A wireless alarm system (10) employs two-way transceivers (32, 60) in a network of smoke detectors (16), a base station (12), and other sensors. A keypad (14) is not needed because the system is reset by pressing a Test/Silence button (66) built into every detector or sensor. A siren is also eliminated because a sounder (64) in every detector sounds an alarm when any sensor is triggered. This is possible because every detector includes a transceiver that can receive alarm messages from any other detector. AC power wiring is also eliminated because the base station and sensors are battery powered. Only a telephone connection (48) is needed if the system is to be monitored. In apartments or dormitory installations, smoke detectors in one apartment relay alarm messages to the next apartment, and onto the next, and so on, to a centralized base station for the entire facility.

Abstract: A key container mountable to the body of a vehicle includes a body and a removable cover. The body has a forward flanged end and a storage portion that may be inserted through an opening defined in the vehicle body. The flanged end has at least one hole adapted to receive a fastener for mounting the flanged end to the outside surface of the vehicle. An internal chamber for storing keys or other items is defined in the storage portion, and the chamber can be accessed through an access opening defined in the flanged end. The removable cover covers the access opening and the fasteners when the cover is coupled to the flanged end. A locking mechanism is coupled to the cover for locking the cover to the body of the key container at any orientation about its central axis.

Abstract: A two-way slam bolt controllably locks a bolt against retraction when impacted on one side by a doorjamb, while still permitting free retraction when impacted on the other side. The preferred embodiment employs a U-shaped bolt that must tilt in one of two directions for retraction.

Abstract: The system comprises a plurality of stationary sensors located in an array within certain physical areas. Each sensor comprises a plurality of antenna coils arranged in unique physical orientations and capable of transmitting radio frequency signals of differing phase. The RFID transponder includes an antenna which receives the signals generated by the antenna coils, and compares the phase of at least two of the signals to determined the relative position of the transponder. The antenna coils may emit two direction finding mode (DFM) signals in succession; the first signal with all antenna coils turned on, the second with a subset of the coils turned off. The spatial relationship of the transponder antenna and individual antenna coils precludes all of the signals in each sensor from being rejected by the transponder during emission of both the first and second DFM signal.

Abstract: A key container has a body with a chamber, an access opening that communicates with the chamber and a cover that can be locked in place over the opening. A key-operated locking assembly is attached to the cover and engagable with the body to lock the cover in place. The cover can be engaged with the body and locked in place without operating the key.

Abstract: A location or other description of the source of a transmission is inserted into the communication as a prefix to transmitter data. A multi-format receiver emits a sequence of different handshakes until the transmitter begins to respond. The receiver stores the prefix and a descriptor of the last handshake prior to the transmitter response. Subsequent signals with a stored prefix are greeted immediately with the stored associated handshake.

Abstract: A cover for an electronic device having a screen that includes a window and at least one device operating feature. The cover is coupleable with the electronic device such that the window of the cover overlies at least a portion of the screen and the electronic device is operable with the device operating feature of the cover.

Abstract: Various enhancements are provided to a pushbutton lock to enhance its security. One is the provision of button tips that are mounted on the ends of the button assemblies and spring-loaded to protrude from the face of the lock, regardless of whether the underlying button is “in” or “out.” By this arrangement, a bystander cannot readily see the button combination by the pattern of depressed buttons. This arrangement also reduces tactile feedback between the underlying button assembly and the externally available button tips, increasing resistance to pick attacks. A further enhancement is the provision of button bars between adjacent pairs of button tips. Whenever any of the button tips is manually depressed, the corresponding button bar is pressed into engagement with, and prevents movement of, a member that must be moved in order to unlock the lock.

Abstract: A motion detector combines an FCC approved homodyne pulsed range-gated radar (“RGR”) detector (10) and a PIR detector (158). Narrow microwave pulses are transmitted at a predetermined pulse repetition frequency (“PRF”) and the pulses are reflected by a target. The RGR detector senses the presence of moving human sized objects within predetermined ranges. Moving objects beyond the ranges are not sensed. The RGR detector employs a pulsed microwave oscillator (12) that is triggered by a system clock (14) and immediately retriggered after a 3 to 100 nanosecond delay (20). The duration of each pulse is 3 to 20 nanoseconds with a half-sine envelope shape. The RGR employs a homodyne detector (36) and shares an antenna (38) with the transmitter. The receiver range is determined by the delay imposed between the transmitted pulses, the first being a transmitted pulse and the second being a local oscillator pulse. Each received 5.8 GHz pulse is mixed down to a baseband by the homodyne detector.

Abstract: Various enhancements are provided to a pushbutton lock to enhance its security. One is the provision of button tips that are mounted on the ends of the button assemblies and spring-loaded to protrude from the face of the lock, regardless of whether the underlying button is "in" or "out." By this arrangement, a bystander cannot readily see the button combination by the pattern of depressed buttons. This arrangement also reduces tactile feedback between the underlying button assembly and the externally available button tips, increasing resistance to pick attacks. A further enhancement is the provision of button bars between adjacent pairs of button tips. Whenever any of the button tips is manually depressed, the corresponding button bar is pressed into engagement with, and prevents movement of, a member that must be moved in order to unlock the lock.

Abstract: The invention provides a method and apparatus for processing video data signals to generate a time division multiplexed video signal which incorporates a maxima number of fields from successive selected video input signals. The invention provides dual video decoder channels associated synchronisation circuits for generating an early synchronisation signal. The early synchronisation signals are applied to control inputs of the video decoders to enable reading of their output earlier than would normally be possible, avoiding delays in the combining of successive fields of video information in the video TDM signal. The provision of dual channels avoids delays due to lack of synchronisation between the different video sources.