Abstract: A method and system for using power and timing estimates to acquire frame acquisition of a reverse CDMA carrier signal. The method includes providing at least one remote transceiver device acquiring a forward CDMA carrier signal, and the one remote transceiver device transmitting a reverse CDMA carrier signal modified to include a frequency associated with the forward CDMA carrier signal. A transceiver base station, in response to determining if the reverse CDMA carrier signal exceeds a reverse CDMA carrier signal threshold (RCCST), uses the frequency embedded in the modified reverse CDMA carrier signal to acquire phase of the reverse CDMA carrier signal. Achieving acquisition the transceiver base station signals a mode change to the remote transceiver. Otherwise, the transceiver base station signals the remote transceiver device to slip the reverse CDMA carrier signal a predetermined number of chips; and/or transmit the reverse CDMA carrier signal at a second power level.

Abstract: An integrating capacitor circuit for an integrating amplifier and related methods are disclosed that allow for efficient detection of currents or charges, particularly those produced by pixel cells in a detector image array. By placing a capacitor-connected field-effect-transistor (FET) in parallel with an integration capacitor and setting its gate voltage to a selected voltage level, the current or charge from the detector depletes the charge on the gate of the FET capacitor while integrating on the capacitor. In addition, the gate voltage level can be adjusted to modify the current depleting characteristics of the capacitor-connected FET. The resulting operation of this integrating circuitry provides significant resulting advantages for the integrating amplifier.

Abstract: A low power self-organizing network is made up of a plurality of wireless communication nodes communicating wirelessly with each other. The nodes each have a sensor providing a respective sensor data value indicative of a physical parameter in the environment of that node. The wireless network discontinues communication with any nodes in which the sensor data value is outside a range of network sensor data values. The network is preferably a group of vehicles moving together, especially a train in which each node is associated with a respective wheel of a railroad car. The nodes are low-power devices that communicate using wireless communications according to a Zigbee protocol. The nodes each have an additional sensor sensing a physical parameter the respective wheel thereof and determines from said electrical signal a degree of degradation of a bearing of the wheel, and transmits data of the degree of degradation to the main node.

Abstract: A method and apparatus for reducing the likelihood of an article becoming jammed in a conveyor system. The width of an article, like luggage, may be detected and the article rotated if the width is greater than a threshold value. A jammed article in the conveyance system may be detected, and repositioned by a positioner, to clear the jam. Spacing between articles in the conveyor system may also be controlled.

Abstract: A circuit and method for correcting phase of a received phase modulated (PM) signal. The method uses k most recently received data bits, which alternate between in-phase I and quadrature Q bits, as an address for a lookup table 60. The lookup table outputs a phase figure 62 derived from a reconstructed waveform. When the most recent k bit is a Q bit, the complement 68 of the phase figure 62 is calculated to yield a phase correction. Otherwise, the phase figure is the phase correction, which is applied to adjust the phase of a delayed version of the received signal. The delayed, phase adjusted signal is then applied to correct the phase of a received signal. The circuit splits an input PM signal in parallel between a matched filter 54 and a delay block 76, 88. The matched filter output provides the input to a register 58 for storing the k data bits. The delay block holds the PM signal until it is input into a loop phase shifter 78 synchronously with the phase correction.

Abstract: Methods for making optically blind reference pixels and systems employing the same. The reference pixels may be configured to be identical to, or substantially identical to, the active detector elements of a focal plane array assembly. The reference pixels may be configured to use the same relatively longer thermal isolation legs as the active detector pixels of the focal plane, thus eliminating joule heating differences. An optically blocking structure may be placed in close proximity directly over the reference pixels.

Abstract: A method of advance baggage screening includes steps of transmitting a threat file corresponding to an item under inspection to a processing center, analyzing the threat file according to a detection algorithm at the processing center to determine a screening result for the item under inspection, and transmitting the screening result to a remotely located operator interface for access by an operator.

Abstract: A communication multiplexer device is provided. The multiplexer device includes a legacy port adapted to communicate a legacy data frame format having at least one major data frame. The legacy major data frame includes overhead fields which may include a sync field. The legacy major data frame also includes three minor frame groups, where each of the minor frame group includes minor frames having subframe formats. The multiplexer also includes a contemporary port adapted to communicate a contemporary data frame format; and a translator coupled between the legacy port and the contemporary port for translation between the legacy data frame format and contemporary data fame format.

Abstract: Method and apparatus for dynamically placing sensors in a 3D model is provided. Specifically, in one embodiment, the method selects a 3D model and a sensor for placement into the 3D model. The method renders the sensor and the 3D model in accordance with sensor parameters associated with the sensor and parameters desired by a user. In addition, the method determines whether an occlusion to the sensor is present.

Abstract: An system for detecting contraband, particularly explosives or other energetic materials. The system includes a source of ionizing radiation that irradiates an item under inspection. The radiation stimulates the emission of RF energy from objects within the item under inspection. The characteristics of the emitted RF energy reveals information about the material composition of the objects. The system detects this emitted RF energy and comparers it to a signature of RF emissions from contraband objects. Apparatus to detect and analyze RF emissions may be constructed as a stand-alone unit or may be incorporated into an imaging system in which the ionizing radiation is used to form an image of the item under inspection. Similarly, the RF analysis may be used, in the first instance, to determine whether an object contains a contraband item or may be used as a second level analysis to clear alarms generated by analysis of images formed by the imaging system.

Abstract: A method estimates a signal to noise ratio (SNR) of a received direct sequence spread spectrum (DSSS) signal. Using the estimated SNR, a control signal is determined that is suitable for modifying a position of a directional antenna. The control signal may be used to modify the position of the directional antenna. In another method, a first estimated SNR is determined for a received radio frequency (RF) signal. An output voltage of an AGC circuit is converted to a second estimated SNR. Using at least the first estimated SNR when the first estimated SNR is within a first range and using at least the second estimated SNR when the second estimated SNR is within a second range, an output SNR is determined. The output SNR may be used to determine the at least one control signal, which may then be used to modify the position of the directional antenna.

Abstract: A multi-level contraband detection system. At a first level, the system obtains volumetric information about an item under inspection. The volumetric information provides a basis for identifying suspect objects in the item under inspection and their locations. The location information is expressed in a first coordinate system relative to the device used for first level scanning. When first level scanning identifies a suspicious object, the item under inspection is passed to a second level scanner that can take further measurements on the suspicious objects. The second level machine is controlled in a second coordinate system. A translation between the two coordinate systems is obtained by registering a multi-dimensional image obtained at the first level with positioning information obtained at the second level. Registration is performed using a coarse and then a fine registration process for quick and accurate registration.

Abstract: The present invention provides an apparatus and method for measuring the angular rotation of a moving body. The apparatus comprises an upper sensor layer, a lower handle layer substantially parallel to the sensor layer, at least one dither frame formed of the upper sensor layer, the frame having a dither axis disposed substantially parallel to the upper sensor layer and the lower handle layer. The apparatus further comprises a first accelerometer formed of the upper sensor layer and having a first force sensing axis perpendicular to the dither axis for producing a first output signal indicative of the acceleration of the moving body along the first force sensing axis, the first accelerometer having a proof mass and at least one flexure connecting the proof mass to the dither frame such that the proof mass can be electrically rotated perpendicular to the dither axis.

Abstract: An system for detecting contraband, particularly explosives or other energetic materials. The system includes a source of ionizing radiation that irradiates an item under inspection. The radiation stimulates the emission of RF energy from objects within the item under inspection. The characteristics of the emitted RF energy reveals information about the material composition of the objects. The system detects this emitted RF energy and comparers it to a signature of RF emissions from contraband objects. Apparatus to detect and analyze RF emissions may be constructed as a stand-alone unit or may be incorporated into an imaging system in which the ionizing radiation is used to form an image of the item under inspection. Similarly, the RF analysis may be used, in the first instance, to determine whether an object contains a contraband item or may be used as a second level analysis to clear alarms generated by analysis of images formed by the imaging system.

Abstract: A circuit and method for correcting timing of a received phase modulated signal. The method uses k most recently received data bits as an address for a lookup table 60. The lookup table includes reconstructed waveforms from which a timing weighing factor is determined. The received PM from time t1 is delayed, phase adjusted, and multiplied by the timing weighing factor, the product of which is used by a timing adjust block 50 to adjust timing of the PM signal at a time after t1. The circuit inputs a PM signal to a timing adjust block 50. The output is split between a matched filter 54 and a loop phase shifter 78. The matched filter feeds alternating I and Q bits into a register 58 that holds k data bits, which are used as an address for a lookup table 60. The output of the lookup table 60 becomes a timing weighing figure, which is multiplied 74 with an output of the loop phase shifter 78 and then input into the timing adjust block 50 for adjusting timing of a PM signal.

Abstract: A re-enterable end-to-end hydrophone assembly which is at least partially transparent, so that the routing of the hydrophone fibers is visible during all phases of assembly and operation. The inventive hydrophone assembly includes a cylindrical sensing mandrel with at least one optical fiber wrapped around its outer wall, and an at least partially transparent oil-filled reference housing attached to the sensing mandrel. The reference housing contains an internal support for holding at least one end of the optical fiber, as well as other hydrophone components such as input couplers, output couplers, and the like. The inventive hydrophone assemblies can be easily disassembled, repaired, and reassembled, facilitating recovery and reuse of expensive optical components.

Abstract: A fast and accurate non-contacting angle sensor. According to one aspect of the described sensor and method of operation thereof, the angular orientation of an inner payload relative to an outer structure is monitored with a 2 axis optical angle sensor for azimuth and elevation angles. The sensor operates on the same principle as an autocollimator, thus it measures both azimuth and elevation angles simultaneously. The angle sensor measurements are highly accurate in the angles of interest, while having low sensitivity to translation in three axes and low sensitivity to roll angle between the inner payload and the outer structure.

Abstract: A system is disclosed that includes a lens system that directs energy from a scene toward a detector and display unit coupled to the detector. The display unit forms an image using information received from the detector. The detector includes an array of detector elements, each detector element receiving energy from a portion of the scene and converting the received energy into information representative of the received energy. The detector sends the information associated with at least some of the detector elements to the display unit. The system further includes a computer coupled to the sensor. The computer selects the detector elements that should be used to form an image based on vehicle operating conditions and instructs the detector which detector elements should have their associated information provided to the display unit.

Abstract: A method for manufacturing optically-transparent lids includes etching sub-wavelength structures on a surface of a lid wafer. The structures may be arrayed in a hexagonally closed-packed pattern.

Abstract: A hardened voyage data recorder includes two subsystems: a removable non-volatile memory and a base containing electronics and firmware for communicating with data sensing systems and for accessing the memory. According to the invention, the memory is protected in a “boiler” and the electronics includes an ETHERNET interface for connecting to shipboard data acquisition devices. The firmware is preferably configured via web pages. A communications protocol for communicating with the recorder is also disclosed.