Abstract: A pre-payment energy metering system uses two-way smart card communications. Secure power line carrier communications are provided at the consumer locations communication between a customer terminal and the utility meter. Two-way secure communication of data is provided through the use of a smart card or memory card which conveys data from the utility service provider to the customer's terminal and also conveys information from the customer's terminal back to the utility. The pre-payment power system of the present invention allows consumers to pay for electricity prior to consumption through the use of the smart card which is loaded with funds at a fully automatic point-of-sale (POS) terminal or at the utility service providers staffed customer service center. Back office software interfaces between the POS terminals and customer service centers, and utility service providers customer information systems.

Abstract: An animal-actuated feeder (20) has a treadle (26) to be tread upon by an animal (36) desirous of obtaining food, a food compartment (24), a cover (30) with closed and open positions (32, 34) denying and granting access to the compartment (24), and linkage (28) to open the cover (30) when the animal (36) treads upon the treadle (26). A damper (88) is coupled to the cover (30) and dampens transit between open and closed positions (32, 34). A dish (106) having a mating lid (108) coupled to the cover (30) promotes the retention of the food in a palatable condition. A plurality of moat assemblies (118) serve as legs for the feeder (20) and inhibit crawling arthropods from gaining access to the food. A control unit (154) and latch (152) control the opening of the cover (30) in response to a tag unit (162) worn by the animal (36) treading upon the treadle (26).

Abstract: An animal-actuated feeder (20) has a treadle (26) to be tread upon by an animal (36) desirous of obtaining food, a food compartment (24), a cover (30) with closed and open positions (32,34) denying and granting access to the compartment (24), and linkage (28) to open the cover (30) when the animal (36) treads upon the treadle (26). A damper (88) is coupled to the cover (30) and dampens transit between open and closed positions (32,34). A dish (106) having a mating lid (108) coupled to the cover (30) promotes the retention of the food in a palatable condition. A plurality of moat assemblies (118) serve as legs for the feeder (20) and inhibit crawling arthropods from gaining access to the food. A control unit (154) and latch (152) control the opening of the cover (30) in response to a tag unit (162) worn by the animal (36) treading upon the treadle (26).

Abstract: Utility consumption data is provided over power line carrier links to local nodes and routed through a network of local nodes over peer-to-peer line-of-sight RF links to a utility service provider. Backhauler nodes combine the utility consumption data from the local nodes within a coverage region for routing to the utility service provider. Consumer nodes include sensing elements for measuring the utility consumption data, and switching elements for connecting or disconnecting the utility from a consumer location. Messages are sent through the network requesting the utility consumption data and for activating the switching elements.

Abstract: Voice call group functionality is provided in a satellite based air traffic control system to allow air traffic controllers and pilots of one or more aircraft to establish and maintain voice communication over a group call. A pilot of an aircraft may maintain voice communication with the same air traffic controller the entire duration of the flight over the entire globe. Voice communication between the pilot of an aircraft may be handed off from one air traffic controller to another by switching voice call groups. The voice call group functionality allows an air traffic controller to communicate simultaneously with pilots of different aircraft, and also allows pilots of different aircraft to communicate with each other.

Abstract: A satellite based broadcast data communications service for a satellite communications system is presented which allows a data information service provider (40) to send large blocks of data information to mobile subscriber units (50). A satellite gateway (30) is coupled to a service provider (40) via a ground link (42) and to a satellite communications network (10) via a gateway link (36). A mobile subscriber unit (50) is coupled to the satellite communications network (10) via both a message link (56) and a high-speed high-bandwidth downlink (58). The mobile subscriber unit sends a data request for requested data information to service provider (40) via message link (56), satellite communications network (10), gateway link (36), gateway (30), and ground link (42).

Abstract: A data message routing and delivery system for an air traffic control system includes a communications network with one or more ground processing nodes, one or more satellite processing nodes, and one or more avionics processing nodes each configured to send and receive data packets to and from others network processing nodes in the communications network. One or more transmission prioritizing controllers are provided to determine the locations of each of network processing node, and to control access to communication channels and routing of data messages in order of priority between the network processing nodes. An application executing on one network processing node is send to an application executing on another network processing node under the control of the transmission prioritizing controllers.

Abstract: A local traffic signal controller (3) is interfaced to a satellite subscriber unit (10) to provide for centralized control of the traffic signals (1) controlled by the local controller (3). A central controller (7) provides central control and can download program control information to local controller (3). Dial-up access to local controller (3) is provided to central controller (7) with the subscriber unit (10). The resultant communication path may be utilized to provide for accessing information from the local traffic signal controller (3). Such information may include indications of lamp failures, traffic pattern information and other status or traffic related information.

Abstract: A direct conversion receiver (DCR)(10) comprises amplitude modulated interference (AMI) nulling circuitry (32) for achieving enhanced cancellation of AMI. The AMI nulling circuitry (32) includes a first signal processor (42) and a second signal processor (44) for processing first and second differential output signals, respectively, from a mixer (24a). The first signal processor (42) includes an adjustable transfer function that is controlled by a controller (50). The controller (50) adjusts the transfer function of the first signal processor (42) to equalize the magnitudes of AMI components in the first and second differential output signals. The first and second differential output signals are then combined in a manner which cancels the equalized AMI components.

Abstract: An autonomous interrogatable information and position device combines the functionality of a satellite communications device capable of sending and receiving voice and digital data messages, a geo-location device capable of self-determining its positional location; an input/output port configured to allow attachment of the device to external local site sensors or equipment in order to obtain external local site sensor data or control the equipment, and a control processor capable of monitoring and responding to positional location information, input sensor data, and incoming voice and digital data messages.

Abstract: A satellite-based air traffic control system utilizes global-coverage satellite communications network to provide voice and data communication between an air traffic control center and one or more aircraft worldwide. Each aircraft is provided with an airborne navigation location reporting system device which has the capability of determining positional information of the aircraft and to transmit and receive voice and data messages to and from the ATC center via the satellite communications network.

Abstract: A battery powered electronic system (50, FIG. 1) is controlled by a movement sensor (20) which senses the acceleration of the electronic system (50). The output of the movement sensor (20) is filtered by an event duration filter (FIG. 2, 120, 121) which determines if the output is of sufficient duration and acceleration to trigger a change in the operation of the electronic system (50). If the acceleration meets the triggering criteria, the electronic system (50) can be made to change an on/off state, an operating mode, or to effect an incremental change in the electronic system (50) such as adjusting the volume or channel setting. Additional movement sensors (20) oriented in different axes can be used to trigger a change in the operation of the electronic system (50) according to a plurality of different directions of acceleration.

Abstract: A survival radio of the type useable in search and rescue operations and carried by the party to be rescued is described. The survival radio includes a GPS receiver, a transceiver and a microcontroller. The microcontroller responds to interrogation messages containing a predetermined identification code for the survival radio to cause a transceiver to transmit a geographic location of the survival radio as derived from GPS signals.

Abstract: In a GPS receiver, power is conserved by powering down P-code circuitry during and utilizing C/A code circuits during times when interfering signals, such as spoofing signals, are not detected. When spoofing is detected, the P-code circuitry is powered up so that the GPS receiver can continue to operate in the presence of spoofing.

Abstract: A sensor apparatus to sense when an aircraft pilot has ejected is provided for safe actuation of a rescue locator radio. The ejection sensor apparatus (20) has a microphone (40), an accelerometer (35) and logic for determining that a pilot ejection event has occurred. The microphone (40) detects the differences in sound level (30) from normal cockpit noise to those during ejection and after deployment of a rescue chute. The accelerometer (35) detects the differences in acceleration level (25) during ejection and after deployment of a rescue chute. Pre-programmed acceptance templates (55) are compared in a digital processor (60) to ensure that ejection has occurred before a rescue radio (90) is activated. A manual turn on delay or turn off capability for the rescue radio is provided for facilitation of communications. Encrypted GPS location information and a pilot code are also included in the rescue radio transmission.

Abstract: A GPS based search and rescue system utilizes an airborne interrogation unit for extending the range of a second interrogation unit. The airborne unit relays communication between a survival radio and the second interrogation unit. The second interrogation unit is typically a ground based unit and is arranged to provide GPS correction information to the survival radio. The normal line of sight communication between a survival radio and an interrogation unit is extended to an over the horizon communication path by utilizing the airborne interrogation unit as a relay for communications.

Abstract: A method and apparatus for automatic tuning calibration of electronically tuned filters which comprises a programmable frequency generator for producing a calibration frequency signal, a filter for filtering the calibration frequency signal, a detector for producing a detector voltage, a processor for programming the frequency generator to specific test frequencies and for producing a stepped filter tuning voltage and storing the detector voltage in response to the stepped filter tuning voltage, and a converter for digital-to-analog conversion of the stepped filter tuning voltage. Calibration frequency signal versus tuning voltage responses are stored for a number of calibration iterations within the usable range of the filter and the resulting table can be used to determine the correct tuning voltage for the filter when operating at any frequency within the usable filter range.

Abstract: A secure, portable position locating radio has a geolocation receiver providing local position and timing information from geolocation means (e.g. GPS satellites) and a local transceiver for sending local position information to a communication system (e.g., an airborne or orbiting transceiver). A crypto unit is provided between the receiver and local transceiver for encrypting the local position information prior to transmission. A data processor coupled to the local transceiver, receiver and crypto unit controls operation of the device, including storing local position information and separating signals broadcast by the communication system into those intended or not intended for the device. An external interface and display and a real-time clock (e.g., slaved to the GPS receiver) are also coupled to the data processor. Encryption keys and message abbreviation codes are conveniently loaded into the device from a demountable accessory unit at the interface, and stored therein.

Abstract: A high power tunable radio frequency circuit which may be used, for example, in a power oscillator, frequency discriminator, diplexer, filter, or a multicoupler comprising a stripline distributed circuit in the influence of a variable magnetic field introduced orthogonally to the plane of the stripline circuit. The stripline is laminated between two layers of planar ferrite members and the D.C. magnetic field intensity is varied to bias the material to a predetermined but variable permeability level, thus changing the propagation velocity of the R.F. signal in the stripline and, therefore, acting to tune the device. Alternately, a microstrip embodiment may be employed utilizing a planar ferrite substrate on one side of the circuit configuration only.