Abstract: An improved system and method for defining an event based upon an object location and a user-defined zone and managing the conveyance of object location event information among computing devices where object location events are defined in terms of a condition based upon a relationship between user-defined zone information and object location information. One or more location information sources are associated with an object to provide the object location information. One or more user-defined zones are defined on a map and one or more object location events are defined. The occurrence of an object location event produces object location event information that is conveyed to users based on user identification codes. Accessibility to object location information, zone information, and object location event information is based upon an object location information access code, a zone information access code, and an object location event information access code, respectively.

Abstract: A system and method for shaping the energy spectrum of a pulse train used by a pulse transmission system. The initial temporal and non-temporal characteristics of pulses comprising the pulse train are established using a designed code or a pseudorandom code and the spectral properties of the pulse train are determined. At least one characteristic of at least one pulse of the plurality of pulses that make up the pulse train are modified or at least one pulse is added or deleted to the pulse train and the spectral properties of the modified pulse train are determined. Whether or not the modification to the pulse train improved the energy spectrum relative to acceptance criteria is determined. The pulse train having the most desirable energy spectrum is selected. The optimization process can also iterate and may employ a variety of search algorithms.

Abstract: A system and a method for position determination by impulse radio using a first transceiver having a first clock providing a first reference signal and a second transceiver placed spaced from the first transceiver. The system determines the position of the second transceiver. The second transceiver has a second clock that provides a second reference signal. A first sequence of pulses are transmitted from the first transceiver. The first sequence of pulses are then received at the second transceiver and the second transceiver is then synchronized with the first sequence of pulses. A second sequence of pulses are transmitted from the second transceiver. The first transceiver receives the second sequence of pulses and the first transceiver is synchronized with the second sequence of pulses. A delayed first reference signal is generated in response to the synchronization with the second sequence of pulses.

Abstract: A system and method for highly selective intrusion detection using a sparse array of time modulated ultra wideband (TM-UWB) radars. Two or more TM-UWB radars are arranged in a sparse array around the perimeter of a building. Each TM-UWB radar transmits ultra wideband pulses that illuminate the building and the surrounding area. Signal return data is processed to determine, among other things, whether an alarm condition has been triggered. High resolution radar images are formed that give an accurate picture of the inside of the building and the surrounding area. This image is used to detect motion in a highly selective manner and to track moving objects within the building and the surrounding area. Motion can be distinguished based on criteria appropriate to the environment in which the intrusion detection system operates.

Abstract: A system and a method for distance measurement utilizes a radio system. The distance is measured by determining the time it takes a pulse train to travel from a first radio transceiver to a second radio transceiver and then from the second radio transceiver back to the first radio transceiver. The actual measurement is a two step process. In the first step, the distance is measured in coarse resolution, and in the second step, the distance is measured in fine resolution. A first pulse train is transmitted using a transmit time base from the first radio transceiver. The first pulse train is received at a second radio transceiver. The second radio transceiver synchronizes its time base with the first pulse train before transmitting a second pulse train back to the first radio transceiver, which then synchronizes a receive time base with the second pulse train. The time delay between the transmit time base and the receive time base can then be determined.

Abstract: A method for positioning pulses over time (via a time layout) applies time-hopping codes having pre-defined characteristics. The time layout can be sequentially subdivided into at least first and second time components that have the same or different sizes. The method applies a first time-hopping code having first pre-defined properties to the first time component and a second time-hopping code having second pre-defined properties to the second time component. The pre-defined properties may relate to the auto-correlation property, the cross-correlation property, and spectral properties, as examples. The codes can be used to specify subcomponents within a frame, and positions (range-based, or discrete) within the subcomponents, where the pulses are positioned.

Abstract: This invention is a computer based system for the assessment, management and instruction of students, and for the delivery of work pages and other instructional materials in the form of electronic student workbooks. The computer based assessment of the student produces a student profile including skill gaps or learning objectives. Teacher (20) and student (22) workstations are networked CPUs with pen-based tablet inputs, and displays network with a central processor (10) and data base. A director workstation may also be networked with the central processor. The central processor generates a teacher workbook either directly or with input from the director workstation. The teacher, or teacher and director together, assemble an electronic student workbook containing instructional materials correlated with the student profile. The system tracks useful data such as instructional material (e.g., textbook pages, work sheets, software, simulations, tests, etc.) delivered to students.

Abstract: A frame reference signal is produced as a function of a clock signal. A first timing generator generates a coarse timing signal having a nominal period and a transition occurring at a precise temporal position with respect to the nominal period. The nominal period is a function of the frame reference signal. The temporal position is a function of a first input timing command and the clock signal. A second timing generator generates at least one fine timing transition as a function of a second input timing command and the clock signal. A combiner circuit uses the coarse timing signal to select one of the at least one fine timing transitions to output a precise timing signal, wherein the precise timing signal has a high temporal precision with respect to the frame reference signal.

Abstract: A coding method for a pulse transmission system specifies temporal and/or non-temporal pulse characteristics according to temporal and/or non-temporal characteristic value layouts having one or more allowable and non-allowable regions. The method generates codes having predefined properties. The method generates a pulse train by mapping codes to the characteristic value layouts, where the codes satisfy predefined criteria. In addition, the predefined criteria can limit the number of pulse characteristic values within a non-allowable region. The predefined criteria can be based on relative pulse characteristic values. The predefined criteria can also pertain to spectral properties and to correlation properties. The predefined criteria may pertain to code length and to the number of members of a code family. The pulse train characteristics may pertain to a subset of the pulse train.

Abstract: A code specifies characteristics of pulses transmitted and received by an impulse transmission system. The invention provides methods for defining non-allowable regions within pulse characteristic value range layouts enabling non-allowable regions to be considered when generating a code. Various approaches are used to define non-allowable regions based either on the pulse characteristic value range layout or on characteristic values of one or more other pulses. Various permutations accommodate differences between temporal and non-temporal pulse characteristics. Approaches address characteristic value layouts specifying fixed values and characteristic value layouts specifying non-fixed values. When generating codes to describe pulses, defined non-allowable regions within pulse characteristic value layouts are considered so that code element values do not map to non-allowable pulse characteristic values.

Abstract: An ultra-wideband magnetic antenna includes a planar conductor having a first and a second slot about an axis. The slots are substantially leaf-shaped having a varying width along the axis. The slots are interconnected along the axis. A cross polarized antenna system is comprised of an ultra-wideband magnetic antenna and an ultra-wideband dipole antenna. The magnetic antenna and the dipole antenna are positioned substantially close to each other and they create a cross polarized field pattern. The present invention provides isolation between a transmitter and a receiver in an ultra-wideband system. Additionally, the present invention allows isolation among radiating elements in an array antenna system.

Abstract: This invention is a computer based system for the assessment, management and instruction of students, and for the delivery of work pages and other instructional materials in the form of electronic student workbooks. The computer based assessment of the student produces a student profile including skill gaps or learning objectives. Teacher (21) and student (23) workstations are networked CPUs with pen-based tablet inputs, and displays network with a central processor (10) and data base. A director workstation may also be networked with the central processor. The central processor generates a teacher workbook either directly or with input from the director workstation. The teacher, or teacher and director together, assemble an electronic student workbook containing instructional materials correlated with the student profile. The system tracks useful data such as instructional material (e.g., textbook pages, work sheets, software, simulations, tests, etc.) delivered to students.

Abstract: The stored energy in the energy-storage capacitors of a power supply during the hold-up time is improved by providing two groups of energy storage capacitors, and by connecting one group of capacitors to the input of a hold-up-time extension circuit that has its output connected to the other group of energy-storage capacitors. Each group of energy-storage capacitors may consist of a single capacitor, or a number of capacitors connected in parallel. The hold-up-time extension circuit is designed so that its output is regulated at a voltage that is lower than the minimum regulation voltage of the output-stage dc/dc converter. As a result, the hold-up-time extension circuit is inactive during the normal operation mode. i.e., when the input voltage is present. In fact, during the normal operation mode both groups of capacitors are effectively connected in parallel so that their voltages are equal.

Abstract: A frequency modulator (100) is provided which includes a VCO (200) having a modulation varactor (122) coupled to its output (128). The VCO (200) includes a resonator stage (112) coupled to an amplifier stage comprising a transistor (118). Coupling of the varactor (122) and the resonator stage (112) is provided via the phase collector capacitance (C.mu.) of the transistor (118).

Abstract: A computer system that has a processor that services interrupts in response to receipt of a signal at the interrupt request has a first device and a second device coupled to the processor. The first device is capable of transmitting a first interrupt request signal that includes an edge transition. The second device is capable of transmitting a second interrupt request signal that comprises a level assertion. An interrupt handler is coupled to the processor and the first and second devices, the interrupt handler receiving the first and second interrupt request signals as inputs and providing the first and second interrupt request signals as outputs to the processor in a sequence according to a predetermined criteria, the first and second interrupt request signals having identical priority.

Abstract: An arrangement of cells with input and output steering circuitry as well as internal shifting capabilities is disclosed which advantageously provides a first in/first out (FIFO) register circuit which can be written to and read from in contiguous clock cycles. The FIFO register circuit is provided with an arrangement of self contained FIFO cells, each cell containing its own input multiplexer and control circuitry.

Abstract: A DMA controller is provided for transferring data between source and destination devices over an I/O bus. The DMA control circuit includes a bus interface unit for providing a bus size information at the beginning of each consecutive bus cycle and a look ahead responsive to the bus size information for providing a bus size control signal. A DMA control circuit responsive to the bus size control signal controls the bus width during contiguous transfer cycles. By dynamically adjusting the DMA control circuit, back to back data reads and writes may occur with no wait states inserted for generating the terminal count information.

Abstract: A bridge interface for a computer system having an industry standard architecture (ISA) bus and a peripheral controller interconnect (PCI) bus is coupled between the ISA and PCI buses. The bridge has a direct memory access (DMA) control circuit programmable by programming signals to perform a DMA transfer, and a scatter/gather unit coupled between the ISA bus and the DMA control circuit. The scatter/gather unit selectively provides the programming signals to the DMA control circuit directly or causes the programming signals to be provided over the ISA bus. Providing the programming signals to the DMA control circuit directly from the programming controller of the scatter/gather unit takes advantage of the location of both the DMA control circuit and the scatter/gather unit on the bridge chip.

Abstract: The queuing of commands on an input/output controller for a parity drive, in a level 4 or level 5 redundant array of inexpensive disk drives responds to receipt of a write instruction with appended data by determining a logical block address of a data drive for the appended data and a logical block address of a parity drive for redundant data belonging to a destination stripe of the appended data. If a parity cache entry corresponds to the parity address, a cache hit has occurred. Responsive to a cache hit, computation of replacement parity data for the stripe may be done from parity data in cache at a location given by the parity cache entry, data read from the data drive and the appended data. The newly calculated parity data is then placed in cache. A command is then sent to an input/output controller for the drive where the parity data is located to write the replacement parity data.

Abstract: An apparatus for transmitting an analog image signal representing an image over a bus including a driver circuit which receives a single ended analog image signal from a media source and provides a differential analog image signal and a switch circuit which selectively provides the differential analog image signal to the bus in response to control information.