Abstract: A position fix identifying a geographic location of a receiver is received. The position fix was generated using signals received at the receiver from respective high-altitude signal sources (such as satellites). Imagery of a geographic area that includes the geographic location is also received. The imagery is automatically processed to determine whether one or more of the high-altitude signal sources were occluded from the geographic location when the position fix was generated. In response to determining that one or more of the high-altitude signal sources were occluded from the geographic location when the position fix was generated, the position fix is identified as being potentially erroneous.

Abstract: The present invention discloses a system and a method for detecting, localizing and categorizing radio frequency (RF) emitting sources. In operation presence of one or more RF sources are determined. Further, movement in the detected one or more RF sources is detected based on at least presence of spread power in spatial harmonics and visibility phase measurement. The frequencies of the radio waves at which the movement of one or more RF sources is detected are identified. A localization antenna subsystem is tuned to the identified frequencies one at a time to localize and identify the RF sources. Furthermore, the RF source is classified as an airborne source or ground-based source using radio interferometry imaging. Finally, on determination that the moving RF source is airborne, the interferometric images are further processed to confirm the type of airborne source.

Abstract: A phase shifter that includes an RF splitter is disclosed. The RF splitter is arranged so that an RF input signal is provided to, and split over portions of, a feed line that connects an antenna element with a radio transmitter/receiver/transceiver, thus realizing a feed line splitter. Feed line splitters described herein are provided with switches that allow changing a point at which the RF input signal is fed to the feed line, where the switches may be semiconductor-based or MEMS-based switches. The point at which the RF input signal is provided to the feed line to be split defines the electrical path length that the RF energy will travel down each respective path of the feed line splitter, which, in turn, changes the phase shift realized at each output of the feed line splitter. Different antenna elements may be coupled to different outputs of the feed line splitter.

Abstract: A method for detecting the spoofing of a signal from a satellite in orbit. A receiver can be located on an aircraft to receive an apparent satellite signal. The method can include determining at least two characteristic signatures of the signal including a power level, and indicating the apparent satellite signal is a spoofed satellite signal.

Abstract: A precise line locator is presented that provides precise line location. The locator includes a housing; a wand attached to the housing, the wand including an array of low frequency antennas arranged along the wand, the array of low frequency antennas defining an electromagnetic locate axis of the line locator system; a real-time kinematic (RTK) Global Navigation Satellite (GNSS) antenna attached to the housing; a user interface positioned in the housing; and a processing circuit coupled to the array of low frequency antennas, the RTK GNSS antenna, and the user interface, wherein the underground line locator determines locate data of the underground line based on signals from the array of low frequency antennas and determines a precise position of the underground line locator from the RTK GNSS antenna.

Abstract: Provided is an information processing method including: acquiring position information associated with installation points of a plurality of observation apparatuses based on signals received from a GNSS satellite by the plurality of observation apparatuses that has executed simultaneous observation, and position information associated with known control points; and generating, by a processor, a check network based on a first automatic generation algorithm by using the position information associated with the installation points of the plurality of observation apparatuses acquired and the position information associated with the known control points.

Abstract: A directional receiver system may include a receiver, a plurality of receive antenna elements, and a circuit. The receiver may include an input port and an output. The plurality of receive antenna elements may be fixedly configured into a known geometric relationship to each other, and each of the receive antenna elements may be connected to the input port of the receiver. The circuit may be coupled to the output of the receiver, configured to determine time differences at which signals from a source are incident upon the antenna elements, and configured to determine an angular orientation of the source to the receive antenna elements based on the time differences.

Abstract: A low sidelobe beam forming method and dual-beam antenna schematic are disclosed, which may preferably be used for 3-sector and 6-sector cellular communication system. Complete antenna combines 2-, 3- or -4 columns dual-beam sub-arrays (modules) with improved beam-forming network (BFN). The modules may be used as part of an array, or as an independent 2-beam antenna. By integrating different types of modules to form a complete array, the present invention provides an improved dual-beam antenna with improved azimuth sidelobe suppression in a wide frequency band of operation, with improved coverage of a desired cellular sector and with less interference being created with other cells. Advantageously, a better cell efficiency is realized with up to 95% of the radiated power being directed in a desired cellular sector.

Abstract: There is provided a beam steerable antenna system including: an antenna array including a plurality of first radiating elements; a first phase control section coupled to the plurality of first radiating elements, the first phase control section being configured to control a phase of signals from the plurality of first radiating elements to output first phase controlled signals; a first combiner coupled to the first phase control section, the first combiner being configured to combine the first phase controlled signals to output a first combined signal; a first frequency converter coupled to the first combiner, the first frequency converter being configured to downconvert a frequency of the first combined signal to output a first downconverted signal; and a second phase control section coupled to the first frequency converter, the second phase control section being configured to control a phase of the first downconverted signal to output a second phase controlled signal.

Abstract: Embodiments herein describe performing AoA resolving to identify a plurality of AoAs corresponding to a multipath signal and then using AP voting to identify a location of the client device. AoA resolving enables an AP to identify the different angles at which a multipath signal reaches the AP. That is, due to reflections, a wireless signal transmitted by a single client device may reach the AP using multiple paths that each has their own AoA. The AP can perform AoA resolving to identify the AoAs for the different paths in a multipath signal. In one embodiment, the AoAs for two APs (or a subset of the APs) can be used to identify cross points or intersection points that represent candidate locations of the client device. A voting module can determine whether those cross points corresponds to AoAs identified by the remaining APs.

Abstract: A system for determining a direction of arrival for signals is provided. The system includes a non-uniform linear array including a plurality of antenna and configured to receive a wireless signal. The system is programmed to receive a plurality of normalized phase candidates for the direction of arrival of the received wireless signal. For each of the plurality of normalized phase candidates, the at least one processor is programmed to calculate a phase error, estimate a plurality of unwrapped measured phases based on the corresponding phase error, and calculate a likelihood based on the corresponding plurality of unwrapped measured phases. The at least one processor is further programmed to select a normalized phase candidate as a direction of arrival estimate based on a comparison of the plurality of likelihood normalized phases.

Abstract: A communication system includes communication units onboard a vehicle system. A first unit receives satellite positioning data and correction data based on phase measurements of satellite signals. A second unit receives the satellite positioning data. One or more processors determine a first geographical position of the first unit based on the position correction data and the satellite positioning data. The processors communicate the position correction data or a copy thereof to the second unit. The processors determine second geographical position data of the second unit based on the position correction data and the satellite positioning data. The one or more processors communicate the second geographical position data that is determined to the first communication unit.

Abstract: Described herein is a method for improving the reception of a satellite navigation message divided in several pages and transmitted by one or several satellites. A satellite navigation message M of k pages is encoded inn pages, and any k retrieved pages from any satellite enables decoding of the original satellite navigation message M. An implementation of the method uses parallel block encoding for a binary erasure channel with high parity and zero overhead, where symbols at a fixed position of all pages are encoded in parallel into shorter codes. This method achieves full page interchangeability in the message transmission, optimizes message reception and reduces decoding cost.

Abstract: An electronic timepiece is provided that executes navigation to a destination site. The timepiece includes a display unit, a magnetic sensor, a reception unit that receives time information indicating a time from a GPS satellite, a storage unit that stores orbit information indicating an orbit of the GPS satellite, and a control unit that generates positional information indicating a position of the electronic timepiece using the time information received by the reception unit and the orbit information stored in the storage unit and executes the navigation using the display unit based on the positional information, an output of the magnetic sensor, and destination site information indicating a position of the destination site. When the orbit information is stored in the storage unit and then a first predetermined time equal to or less than a valid period of the orbit information elapses, the control unit updates the orbit information stored in the storage unit.

Abstract: Disclosed by way of example embodiments is a wireless communication system transmitting or receiving a wireless signal according to an orientation of the wireless communication system. In one aspect, the wireless communication system includes an antenna operable in different configurations. In each configuration, the antenna has a corresponding antenna gain in a direction with respect to the antenna. The wireless communication system further includes a sensor for determining an orientation of the wireless communication system. According to the determined orientation, the antenna is configured to transmit or receive the wireless signal in a corresponding configuration. Hence, the wireless communication system disposed in different orientations can successfully communicate with another wireless communication system.

Abstract: A method for launching a round from an airborne platform, receiving a plurality of RF signals at the round, determining an amount of time between a first and second received RF signal, where the second signal is a multi-path signal and the first signal is a direct path signal. An altitude of the round is determined based on the delay between the first and second received signal and aligning the round's flight path with an initial velocity vector of the aircraft platform to reduce dispersion. The round can include a plurality of sensors for detecting the RF signals. The second received RF signal may be a multi-path signal having been reflected off of the earth's surface or another object on the earth's surface. The altitude of the round can be determined using the known altitude of the airborne platform, the delay of time between the first and second received signals, and the speed of light.

Abstract: An angle of arrival (AoA) of an electromagnetic wave is determined. A phase of an antenna signal associated with each of two receive antenna is measured. A measured phase difference of arrival (PDoA) of the electromagnetic wave is determined based on the measured phase of each of the antenna signals. The measured PDoA is corrected based on one or more crosstalk factors associated with the two receive antennas. The AoA of the electromagnetic wave at the two receive antenna is generated based on the corrected measured PDoA.

Abstract: A method and device for estimating the time of arrival (ToA) of a radio signal are proposed. The radio signal comprises M subsignals carried on M subcarriers, where M is an integer ?2. The number of propagation paths and the time of arrival associated with a first path are estimated. The technique can improve ToA estimation accuracy, especially in a multipath fading channel, and reduce the need for channel information.

Abstract: Disclosed are a positioning communication device, a positioning method, and a computer storage medium.

Abstract: A phase shifter that includes an RF splitter is disclosed. The RF splitter is arranged so that an RF input signal is provided to, and split over portions of, a feed line that connects an antenna element with a radio transmitter/receiver/transceiver, thus realizing a feed line splitter. Feed line splitters described herein are provided with switches that allow changing a point at which the RF input signal is fed to the feed line, where the switches may be semiconductor-based or MEMS-based switches. The point at which the RF input signal is provided to the feed line to be split defines the electrical path length that the RF energy will travel down each respective path of the feed line splitter, which, in turn, changes the phase shift realized at each output of the feed line splitter. Different antenna elements may be coupled to different outputs of the feed line splitter.