Abstract: An ultra wideband (UWB) or short-pulse RF system is disclosed that can be used to precisely locate or track objects (such as personnel, equipment, assets, etc.) in real-time in an arbitrarily large, physically connected or disconnected, multipath and/or noisy environment. A system implementation includes multiple zones or groups of receivers that receives RF signals transmitted by one or more timing reference tags and one or more objects having associated object tags. Each zone or group may share a common receiver. By combining a multiple reference tag system with a virtual group of receivers, i.e., a zoning technique or system, a cost-effective system can be provided that offers scalability and flexibility to monitor a significantly expanded coverage area.

Abstract: Various methods and apparatuses that utilize a wireless time reference system are provided herein. One example method involves calibrating independent, spatially-located clocks of a geoposition system in order to geolocate an object having an associated object tag. The example method may include transmitting an RF pulse pair, receiving the pulse pair at multiple locations, utilizing respective frequencies of first and second spatially-located clocks to produce count values to effect measurement of an interarrival interval at each of multiple locations, determining a ratio of count values relative to said first and second spatially-located clocks, and utilizing said ratio to calibrate time indications of said clocks. Other related methods and apparatus are also provided.

Abstract: An ultra wideband (UWB) or short-pulse RF system is disclosed that can be used to precisely locate or track objects (such as personnel, equipment, assets, etc.) in real-time in an arbitrarily large, physically connected or disconnected, multipath and/or noisy environment. A system implementation includes multiple zones or groups of receivers that receives RF signals transmitted by one or more timing reference tags and one or more objects having associated object tags. Each zone or group may share a common receiver. By combining a multiple reference tag system with a virtual group of receivers, i.e., a zoning technique or system, a cost-effective system can be provided that offers scalability and flexibility to monitor a significantly expanded coverage area.

Abstract: Various methods for determining a configuration of a communications system are provided, including methods for determining system node positions. One example method includes generating a node attribute information segment, and adding the node attribute information segment to an attribute information message at a position within the attribute information message indicative of a position of a node within a series string of communications connections. Some of the methods may be implemented within the context of an asset locating system that analyzes the timing of wireless signals to determine a location of the source of the signal. Related systems and apparatuses are also provided.

Abstract: Various methods for performing amplifier gain compensation to correct for variations in temperature are provided. One example method includes modifying a gain adjustment value based on a current temperature reading, receiving a signal, applying a gain adjustment to the signal based on the gain adjustment value, comparing the gain adjusted signal to a plurality of thresholds to generate respective comparison outputs, and selecting one of the comparison outputs for use in determining content and timing information of the received signal. Related systems and apparatuses are also provided.

Abstract: Instead of normalizing time reference of independent spatially-located clocks using a reference tag transmission from known location, the present invention uses an interarrival time interval between a pulse pair of UWB pulses as a timing metric. Thus, a method of synchronizing spatially-located clocks or normalizing time indications thereof comprises transmitting a UWB pulse pair, determining at first and second monitoring stations a respective count value indicative of a locally measured time interval between received pulse pairs, determining a ratio between clock counts of first and second monitoring stations, and utilizing the ratio to determine clock skew, e.g., a timing correction to be applied to respective local clocks of the monitoring stations.

Abstract: An ultra wideband (UWB) or short-pulse RF system is disclosed that can be used to precisely locate or track objects (such as personnel, equipment, assets, etc.) in real-time in an arbitrarily large, physically connected or disconnected, multipath and/or noisy environment. A system implementation includes multiple zones or groups of receivers that receives RF signals transmitted by one or more timing reference tags and one or more objects having associated object tags. Each zone or group may share a common receiver. By combining a multiple reference tag system with a virtual group of receivers, i.e., a zoning technique or system, a cost-effective system can be provided that offers scalability and flexibility to monitor a significantly expanded coverage area.

Abstract: Instead of normalizing time reference of independent spatially-located clocks using a reference tag transmission from known location, the present invention uses an interarrival time interval between a pulse pair of UWB pulses as a timing metric. Thus, a method of synchronizing spatially-located clocks or normalizing time indications thereof comprises transmitting a UWB pulse pair, determining at first and second monitoring stations a respective count value indicative of a locally measured time interval between received pulse pairs, determining a ratio between clock counts of first and second monitoring stations, and utilizing the ratio to determine clock skew, e.g., a timing correction to be applied to respective local clocks of the monitoring stations.

Abstract: Instead of normalizing time reference of independent spatially-located clocks using a reference tag transmission from known location, the present invention uses an interarrival time interval between a pulse pair of UWB pulses as a timing metric. Thus, a method of synchronizing spatially-located clock or normalizing time indications thereof comprises transmitting a UWB pulse pair, determining at first and second monitoring stations a respective count value indicative of a locally measured time interval between received pulse pairs, determining a ratio between clock counts of first and second monitoring stations, and utilizing the ratio to determine clock skew, e.g., a timing correction to be applied to respective local clocks of the monitoring stations.

Abstract: A method and system to produce a spectrally filtered ultra wideband (UWB) signal preferably utilizing a singly terminated filter having an input section and a current switching device directly coupled to the input section. The switching device is operated in a highly nonlinear manner such that an impulse of energy excites the filter in such a way that a vast majority of impulse energy is transmitted to an antenna after spectral filtering thereby yielding a highly efficient, broadband (e.g., ultra wideband) transmission. A substantial fraction of the current switched into the filter passes directly to the antenna. Optionally, the input section of the filter possesses a secondary resonance and the current switching device has a conduction time chosen to be compatible with the secondary resonance.

Abstract: A system for identification and tracking of a tag distributed in a room is presented. A laser base station is configured to scan laser beams through a portion of a room. A tag is configured to be reactive to incident laser beams scanned from the laser base station to provide a data signal back to the laser base station. A tag tracking system is configured to receive input derived from the data signal from the laser base station. The tag tracking system stores state records of position and informational content of the tag generated from the input. The tag tracking system determines angular position of the tag with respect to the laser base station based on the position and information content of the tag stored in the state records.

Abstract: A system for identification and tracking of a tag distributed in a room is presented. A laser base station is configured to scan laser beams through a portion of a room. A tag is configured to be reactive to incident laser beams scanned from the laser base station to provide a data signal back to the laser base station. A tag tracking system is configured to receive input derived from the data signal from the laser base station. The tag tracking system stores state records of position and informational content of the tag generated from the input. The tag tracking system determines angular position of the tag with respect to the laser base station based on the position and information content of the tag stored in the state records.

Abstract: A rotation mechanism for bichromal balls in a twisting ball display is based on electrostatic induction. A bichromal ball with hemispherically differentiated electrical time constants is immersed in a dielectric liquid containing a charge director solution. The liquid is contained within an encapsulant. The charge director solution has positive and negative ions with substantially different mobilities. Space charge clouds created in this fluid upon application of an electric field act so as to induce polarization differently in each hemisphere, leading to a net dynamic polarization. Interaction between the space charge and the induced polarization serves to rotate the ball. Ions are subsequently trapped at the fluid/encapsulant interface due to greater polarizability of the encapsulant. A threshold is obtained by the excess field needed to release the ions and so reverse the ion motion.

Abstract: An RF object locating system and method that uses or includes a set of N (N>2) receivers (monitoring stations) located at fixed positions in and/or about a region to be monitored, one or more reference transmitters that transmit a timing reference, a location processor that determines object location based on time-of-arrival measurements, and at least one object having an untethered tag transmitter that transmits RF pulses, which may additionally include object ID or other information. Free-running counters in the monitoring stations, whose phase offsets are determined relative to a reference transmitter, are frequency-locked with a centralized reference clock. Time-of-arrival measurements made at the monitoring stations may be stored and held in a local memory until polled by the location processor.

Abstract: A transceiver for short-pulse radar applications is disclosed in which a shift register or the like is used to collect return signal information in a manner to reduce the number of transmit pulses needed and to increase the speed of determining the positions of multiple scattering objects. In addition, there is also disclosed cooperating transceivers arranged as transponders similarly utilizing shift registers or other pulse sampling techniques to accurately determine the linear distance between them based on relationships between or among propagation time, measured offsets, and internal clock skews. Corresponding methods are also disclosed.

Abstract: A system for identification and tracking of microwave responsive tags, the system comprising, a microwave responsive tag having a passive modulating element to uniquely backscatter directed microwave beams, a microwave base station for directing microwave beams in room sized areas, and a tag tracking system receiving input from the microwave base station, the tag tracking system storing state records of position and informational content of the microwave tag.

Abstract: A transceiver for short-pulse radar applications is disclosed in which a shift register or the like is used to collect return signal information in a manner to reduce the number of transmit pulses needed and to increase the speed of determining the positions of multiple scattering objects. In addition, there is also disclosed cooperating transceivers arranged as transponders similarly utilizing shift registers or other pulse sampling techniques to accurately determine the linear distance between them based on relationships between or among propagation time, measured offsets, and internal clock skews. Corresponding methods are also disclosed.

Abstract: A system and method for detecting the presence or absence of cars, locomotives, or obstructions which may occupy a particular section of track of a model railroad. Digital Command Control signals are used to provide the excitation voltage needed to perform a measurement of the capacitance of an unoccupied section of track. Deviations from this unoccupied capacitance are then measured to indicate occupancy.

Abstract: An RF object locating system and method that uses or includes a set of N (N>2) receivers (monitoring stations) located at fixed positions in and/or about a region to be monitored, one or more reference transmitters that transmit a timing reference, a location processor that determines object location based on time-of-arrival measurements, and at least one object having an untethered tag transmitter that transmits RF pulses, which may additionally include object ID or other information. Free-running counters in the monitoring stations, whose phase offsets are determined relative to a reference transmitter, are frequency-locked with a centralized reference clock. Time-of-arrival measurements made at the monitoring stations may be stored and held in a local memory until polled by the location processor.

Abstract: An internal field activated display sheet is disclosed which comprises a medial plane disposed between reservoirs in the display sheet. The reservoirs communicate with each other through apertures in the medial plane, which includes a plurality of conductors. At least one of the reservoirs is filled with a liquid means, which is responsive to a peristaltic internal field developed within the medial plane. Applying a field across selected apertures in the medial plane causes the liquid means to be electrically pumped from one reservoir into the other, thereby displaying an image.