Abstract: A selection method of satellites for RTK positioning calculation includes initializing a mask threshold of the elevation angle mask and/or the signal strength mask, setting the mask threshold as a first mask threshold other than a mask threshold which carried out an initial setting, performing a first RTK positioning calculation based on a signal from the satellite, performing a first quality check about a positioning solution in the first RTK positioning calculation, and when the first quality check is under the threshold of the ratio test, performing a second RTK positioning calculation based on the signal from the satellite newly chosen via the first mask threshold and performing a second quality check about a second positioning solution in the second RTK positioning calculation.

Abstract: To reduce power consumption in a user terminal, especially mobile devices, a system and method are introduced that use terrestrial beacons as a location proxy when satellite positioning signals are not available. The geographic locations of the terrestrial beacons need not be known to use the beacons as a proxy for a satellite positioning signals derived location.

Abstract: Systems and methods are provided for determining position location information in a wireless network. In one embodiment, timing offset information is communicated between multiple transmitters and one or more receivers. Such information enables accurate position or location determinations to be made that account for timing differences throughout the network. In another embodiment, transmitter phase adjustments are made that advance or delay transmissions from the transmitters to account for potential timing differences at receivers. In yet another embodiment, combinations of timing offset communications and/or transmitter phase adjustments can be employed in the wireless network to facilitate position location determinations.

Abstract: A method of determining adequacy of acquisition includes: attempting to acquire a satellite signal from a satellite and decoding first satellite orbit data; and determining the adequacy of acquisition of the satellite signal by using the first satellite orbit data and second satellite orbit data that has been acquired from the satellite.

Abstract: A satellite system for detecting radio frequency signals from space including at least two sensors, a processing unit and at least one receiver. Each sensor receives a plurality of radio frequency signals containing messages and outputs a sensor signal that is representative of the plurality of radio frequency signals. The processing unit selects a predetermined number of mathematical combinations of the sensor signals and combines the sensor signals into the predetermined number of mathematical combinations to produce a plurality of zone signals. The characteristics of each zone signal are undefined at the time the predetermined number of mathematical combinations is selected. The receiver extracts the messages contained in the zone signals.

Abstract: Methods and apparatus are presented for improved productivity in determining static position of an antenna of a GNSS rover, such as in stop-and-go surveying. Computer-implemented methods and apparatus provide for determining a static position of an antenna of a GNSS rover from observations of GNSS signals collected at the antenna over multiple epochs and from correction data for at least one of the epochs.

Abstract: A frequency synthesizer in a GNSS receiver chip enables duty cycling operation of the frequency synthesizer. The frequency synthesizer is cycled on to generate required clock signals for the GNSS receiver chip, and cycled off during a measurement duty cycle comprising measurement available intervals and measurement unavailable intervals. A reference clock inputted to the frequency synthesizer is on during the measurement duty-cycle. During the measurement available intervals, the frequency synthesizer is cycled on to generate the required clock based on the reference clock. During the measurement unavailable intervals, the frequency synthesizer is cycled off and clock timing is maintained based on the reference clock. A number of elapsed clock cycles of the reference clock is captured for a measurement unavailable interval and transferred to a clock offset. The GNSS receiver chip processes signals received using the required clock and the clock offset in a following measurement available interval.

Abstract: An antenna array for the transmission of signals is disclosed which comprises a plurality of antenna elements connected to a plurality of transceivers. The plurality of transceivers receive transceiver signals for transmission to the plurality of antenna elements. The antenna comprises a failure detector or monitoring and control system connected to the plurality of transceivers, which autonomously detects malfunction of the individual transceivers and reports this to the signal processor without involvement of the transmitter and receiver. The antenna array also comprises a signal processor connected to the plurality of transceivers and adapted to weight using complex values the transceiver signals for automatically compensating for power losses by tilt adjustments and for interference by suppression of sidelobes of the signals based on the information from the failure detector or monitoring and control system.

Abstract: To enable high-speed learning of an antenna directionality to be used for millimeter-wave communication, there is provided a communication device including a first radio communication unit capable of radio communication in accordance with a first communication method, and a second radio communication unit capable of radio communication in accordance with a second communication method using a higher frequency band than the first communication method, in which, upon receiving an instruction signal instructing to learn a beam directionality, the first radio communication unit determines a reception start time point of a beam reference signal based on the instruction signal, and the second radio communication unit starts reception of the beam reference signal from the reception start time point determined by the first radio communication unit and determines a parameter value for specifying an optimum beam pattern based on the received beam reference signal.

Abstract: A system for aligning two ground-based antennae (100, 110) or a ground-based antenna (100) and a satellite antenna (110), for use in military and civilian settings, in which a visual display is generated showing a graphical representation of the antennae including graphical representations indicating both the axis of the main lobe (102) and the approximate radiation pattern (414) of the antennae, superimposed over a live imaging of the local terrain. The alignment is achieved when the graphical representations of the main axis and radiation patterns of the two antennae align with each other.

Abstract: Apparatus for longitudinally segmenting a cruciform shaped irradiated boiling water reactor control rod having four elongated blades radially extending from a central spline, into four flat panels. The apparatus employs a double bladed band saw with the band saw blades orthogonally oriented at two different elevations and having one side of each band saw blade crossing over the center of the spline of the control rod in between the control rod blades.

Abstract: A nuclear component transfer device that incorporates a shielded canister into the mast design of a conventional nuclear refueling machine. A moveable mast telescopes within a stationary mast which is attached to a bridge for lateral positioning. The canister allows for the addition of shielding that is positioned with the movement of the moveable mast without additional motorized components to deploy the shielding during nuclear component movement. The nuclear component is drawn up into the shielded canister as the moveable mast lifts the nuclear component. The nuclear component is then placed into a transfer cart that is also fitted with a shielded canister. The transfer is made without exposing the nuclear components resulting in completely shield movement.

Abstract: An optimum measurement subset with a specified number n of elements is generated from a set of N>n weighted input global navigation satellite system (GNSS) measurements. A group of trial measurement subsets is generated by removing a different individual weighted input GNSS measurement from the set. A value of accuracy criterion for a target parameter is calculated for each trial measurement subset, and the trial measurement subset with the minimum value of accuracy criterion is selected. A new group of trial measurement subsets is generated by removing a different individual weighted GNSS measurement from the previously selected trial measurement subset. A value of accuracy criterion is calculated for each new trial measurement subset, and a new trial measurement subset with the new minimum value of accuracy criterion is selected. The process is repeated until the selected trial measurement subset has the specified number n of elements.

Abstract: The present invention provides a system and method for determining the authenticity of reported positions of GNSS receivers, such as aircraft equipped with GPS positioning devices, and provides an in-band verification capability for GNSS positions by tasking one or more GNSS satellites as designated authentication support (DAS) satellites that transmit corrupted ephemeris data in a pseudo-random error corrupted C/A signal on the L1 band, and the GNSS receivers determine authentication ranges to the DAS satellites and transmit the DAS authentication ranges as part of their position report. The surveillance system can verify the authenticity by comparing the transmitted authentication ranges to true authentication ranges determined using actual ephemeris data and the known C/A code pseudo-random error for the DAS satellites.

Abstract: An antenna apparatus for determining the position of a radio-frequency transponder is provided, comprising a phased array of antennas enabled to transmit and receive power at a given frequency for communicating with a radio frequency (RF) transponder, the phased array being movable; and a phase shifter for providing a phase shift to at least one antenna of the phased array to provide a minima in a main radiated lobe of the phased array, such that when the phased array is moved from a first position, for detecting the RF transponder via the main radiated lobe, to a second position, where a signal from the RF transponder is minimized, a position of the RF transponder determined to be along an axis of the minima in the second position.

Abstract: The present system relates to a GNSS receiver that includes a processor. The processor is configured to receive a temperature signal from a temperature sensor indicating an operating temperature of an resonator. The processor is also configured to compute a frequency and a frequency correction data of the resonator based on the temperature and a frequency model of the resonator. The processor then transmits the frequency correction data to an RF receiver which utilizes the frequency correction data and the resonator to receive and RF signal.

Abstract: A scan alignment system and method for calibrating a scan path for a directional antenna system is presented. The scan alignment system calibrates the scan path by generating a scan path, scanning the directional antenna through the scan path, receiving a signal signature responsive to the scanning, comparing the signal signature with a reference signature, and determining a corrective calibration to apply to the scan path that minimizes the difference between the signal signature and the reference signature. In an embodiment, the reference signature is modeled based on the directional antenna and the intended scan path.

Abstract: Techniques for the design of low cost, low complexity phased arrays are described. The techniques allow control of the phase progression in the entire phased array by using only one phase shifter for a bank of arrays. In some examples, the phased array includes directional couplers, amplifying stages, power combiners and a phase shifter. The phase shifter may be of various kinds, including simple and compact phase shifters formed of varactor diodes and inductors or transmission lines.

Abstract: Dynamic inter-channel bias calibration of a navigational receiver is provided. A reference signal is propagated through front-end circuitry of the receiver. A delay caused by the propagation of the reference signal through the front-end circuitry is measured. The inter-channel bias of the navigational receiver is reduced using the measured delay associated with the front-end circuitry of the receiver.

Abstract: A method for extracting tritium from irradiated boiling water reactor control rods that have cruciform-shaped. Bands of a malleable metal are wrapped around the flat portions of the blades, one band near the top of each blade panel and a second band near the bottom. The bands are crimped and an inlet penetration is formed through one of the bands and the panel and an outlet penetration is formed through the second band and the panel. A termination of each end of a closed loop conduit is sealably connected to the inlet and outlet for transporting a carrier gas through the interior of the panel. The carrier gas passing through the interior transports the tritium out of the panel to a tritium getter filter to capture the tritium. The carrier gas then recirculates through the system.