Abstract: A vehicle direction estimation section estimates an absolute direction of a heading direction of a vehicle based on GPS information and vehicle information. A satellite direction estimation section estimates an absolute direction of a target satellite of several satellites for positioning based on corresponding GPS information, and estimates a relative direction of the target satellite with respect to the heading direction based on the estimated absolute direction of the heading direction and the estimated absolute direction of the target satellite. A shield determination section determines a shielded state of the target satellite by determining whether a signal strength of a satellite signal from the target satellite is greater than a threshold value relative to a target partition of several partitions into which a three-dimensional sphere with respect to the heading direction is divided, the target partition which the calculated relative direction of the target satellite belongs to.

Abstract: A vehicle-to-vehicle communication filtering system is provided to selectively process broadcast messages between a host vehicle and a remote vehicle. A processing unit evaluates a time-to-collision status between the host vehicle and the remote vehicle sending the message. The time-to-collision status is a function of a relative distance and a relative velocity between the host vehicle and the remote vehicle which are determined from data provided within a first portion of the message received from the remote vehicle. An attentive factor is assigned to each of the remote vehicles based on the time-to-collision with respect to each remote vehicle. The attentive factor identifies a proportion of messages broadcast from the remote vehicle to be targeted for security processing. Security processing of the message is performed based on a second portion of the message unless the attentive factor indicates the message should be ignored.

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: A system and method of calculating corrections to a navigation solution based on accurate data are provided. GNSS ephemeris, clock models and other navigation information are received from at least three GNSS satellites and pseudo-ranging to the GNSS satellites is performed. A PVT solution is resolved from the GNSS ephemeris, clock models, and other navigation information and the pseudo range measurements. The PVT solution includes a statistical measure. Differential GNSS data for calculating the corrections to the PVT solution is received and a corrected PVT solution is calculated based upon the differential GNSS data. The corrected PVT solution is compared to a region defined by the statistical measure and the corrected PVT solution is rejected when the corrected PVT solution is not within the region.

Abstract: The present invention is related to location positioning systems, and more particularly, to a method and apparatus for making accuracy improvements to a GPS receiver's navigation calculations. According to a first aspect, the invention includes maintaining a table of height attributes for major cities and urban areas around the world (contour table) in the GNSS chipset. The information in the table preferably includes latitude, longitude of the city along with height attributes of those cities, such as the average, min, max height and region boundary etc. Additional information such as average gradient could also be saved in the table. According to further aspects, when GPS signals are degraded in environments such as urban canyons, the height information can be obtained from the table and used to improve the navigation solution.

Abstract: The subject matter disclosed herein relates to receiving one or more SPS signals at two or more physically separated antennae. In an aspect, signals from the physically separated antennae may be downconverted into complex digital signals that may undergo further processing to improve one or more performance metrics related to position estimation operations, for example.

Abstract: To provide an art that can improve a performance of a GNSS receiver. A GNSS receiver 100 includes a receiver 1, a navigation message acquiring unit 3, a navigation message processor 5, and a calculator 6. The receiver 1 receives signals from satellites. The navigation message acquiring unit 3 acquires predetermined information in navigation messages contained in the signals received by the receiver. The navigation message processor 5 outputs either one of the same kind of information in the plural different kinds of navigation messages, which is acquired by the navigation message acquiring unit 3. The calculator 6 performs a calculation based on the information outputted from the navigation message processor 5.

Abstract: An attenuated satellite positioning system (SPS) signal is acquired using long integration over multiple navigation data bits. To produce a stable internal clock signal to perform the long integration, an external clock signal is received from a highly stable source, such as a wireless communication base station or a nearby femtocell. An internal oscillator is driven at a desired frequency that is aligned with the scaled frequency of the external clock signal to produce the stable internal clock signal. The SPS signal is received and integrated for an extended period using the internal clock signal. Predicted SPS data may be received from an external source and used to perform coherent integration. Alternatively, non-coherent integration may be performed. Additionally, a motion sensor may be used to determine if there is motion relative to the external clock source or to compensate for Doppler errors in the external clock signal due to motion.

Abstract: A system, methods, and apparatus for dual antenna transfer switching are disclosed. In an example embodiment, a dual antenna system includes antennas, antenna control units, a transfer switch, and a modem. For example, the transfer switch may transfer a connection between antennas based on changing satellite visibility, upon entering a preprogrammed blockage zone or an unexpected loss of satellite visibility. The transfer switch may receive GPS data from an external GPS unit and/or the antenna control units and buffer the GPS data to a modem. The transfer switch may provide a modem receive-lock signal to retarget a line of sight. The transfer switch may transfer the connection between the antennas based on satellite visibility including signal reception quality and/or a modem receive-lock status. The transfer switch may, based on a difference in antenna uplink transmission power, attenuate a higher power antenna to be balanced with a lower power antenna.

Abstract: Each of a first and a second navigation satellite system (NSS) are adapted to operate according to a first and a second specification, respectively, and each includes a first and a second plurality of satellite vehicles (SVs), respectively. Each of the first and the second plurality of SVs are adapted to be identified by a first and a second plurality of unique corresponding identifications (IDs), respectively. A processor is adapted to receive and identify a first plurality of corresponding signals transmitted from the first plurality of SVs in response to the first plurality of unique corresponding IDs. The processor is adapted to receive and identify a second plurality of corresponding signals transmitted from the second plurality of SVs in response to the second plurality of unique corresponding IDs. The processor is adapted to determine position location information in response to receiving and identifying the first plurality of corresponding signals and the second plurality of corresponding signals.

Abstract: According to an embodiment of the present invention an emitter geolocation technique determines the geolocation of a radio frequency (RF) emitter using pair-wise line-of-bearing intersections that are derived from signal-to-noise ratios of transmitted signals received at a sensor. The technique may be employed with ground based vehicle or small unmanned air vehicles (UAV), and obtains reliable geolocation estimates of radio frequency (RF) emitters of interest.

Abstract: Angle of arrival and/or range estimation within a wireless communication device. Appropriate processing of communications received by a wireless communication device is performed to determine the angle of arrival of the communication (e.g., with respect to some coordinate basis of the wireless communication device). Also, appropriate processing of the communications may be performed in accordance with range estimation as performed by the wireless communication device to determine the distance between the transmitting and receiving wireless communication devices. There are two separate modes of packet processing operations that may be performed: (1) when contents of the received packet are known, and (2) when contents of the received packet are unknown. The wireless communication device includes a number of antenna, and a switching mechanism switches from among the various antennae capitalizing on the spatial diversity of the antennae to generate a multi-antenna signal.

Abstract: The invention relates to a slot antenna, more particularly to a transmitting antenna for RFID, comprising an antenna contour board having a plurality of antenna slots and at least one control circuit for enabling the antenna contour board to transmit and/or receive electromagnetic radiation. The slot antenna is characterized in that in at least one antenna slot of the antenna contour board there is inserted a circuit board carrying a control circuit. The invention further relates to an RFID method involving the use of the slot antenna of the invention.

Abstract: Methods and apparatus are provided for processing a set of GNSS signal data derived from observations of GNSS signals of multiple transmitters over multiple epochs, the GNSS signals having a first signal and a second signal in a first band which can be tracked as a single wide-band signal and each of which can be tracked separately, comprising: obtaining carrier-phase observations of the first signal, obtaining carrier-phase observations of the second signal, obtaining code observations of the wide-band signal, and estimating from a set of observables comprising the carrier-phase observations of the first signal, the carrier-phase observations of the second signal and the code observations of the wide-band signal values for a set of parameters comprising: position of a receiver of the GNSS signals, clock error of a receiver of the GNSS signals, and an array of ambiguities comprising an ambiguity for each transmitter from which carrier-phase observations of the first signal are obtained and an ambiguity for ea

Abstract: A method of processing data signals suitable for providing positioning information comprises sequentially recording blocks of data samples of a satellite broadcast from the beginning of a period of time of interest, and storing them in memory. When the memory is full, previously stored blocks of data samples are overwritten, such that the average quantity of sample data decreases, and wherein the memory content includes blocks of data samples covering substantially the full period of time of interest. This method enables blocks of data samples to be kept in memory for a full period of interest (for example a journey) but allows a limited memory capacity. The use of the memory is intelligent and dynamic.

Abstract: A method of geolocating a stationary transmitter observed by a fixed receiver device and at least two receiver devices, at least one of the receiver devices moving includes obtaining wavelength-scaled phase difference measurements between pairs of receiver devices, and obtaining a result lattice of possible locations of the transmitter, one location more probable than the remainder. A method of geolocating a moving transmitter observed by a plurality of fixed or nearly fixed receiver devices, and a moving receiver device, includes obtaining wavelength-scaled phase difference measurements from the plurality of fixed or nearly fixed receiver devices to obtain a shape of the transmitter trajectory, measuring the phase difference between the moving receiver device and at least one of the plurality of fixed or nearly fixed receiver devices to obtain a phase error residual, and moving an estimated starting point of the transmitter to obtain a best-fit residual.

Abstract: A method for the geolocation of a device transmitting a signal containing at least one message to a plurality of relay satellites in a medium earth orbit, visible from said device, receiving said message and transmitting it to processing means, comprises at least the following steps: determination of the times of reception of the message by the relay satellites; determination of the pseudo-distances between the device and the relay satellites; searching for and acquiring a minimum number N of satellite radio navigation signals; determination of the time lags between the transmission of the radio navigation signals and their reception by the said device; broadcasting by the device of these time lags in the message; and, determination of the position of the device from at least the pseudo-distances, from the time lags and from the positioning coordinates of the relay satellites and of the radio navigation satellites.

Abstract: Techniques for watching a location of a device with respect to a destination target include obtaining a current location of a device from a localization operation, calculating an interval, and performing a next localization operation after the interval has expired. The interval may be calculated based on a velocity and a distance from the current location to a destination target. The techniques may also include calculating a displacement distance from the current location and adjusting the interval based on the displacement distance to thereby adjust a time for performing the next localization operation. The techniques may include performing state detection to determine a motion state of the device and performing the next localization operation based on the determined motion state.

Abstract: A network node such as a positioning node, and a related method of determining an uncertainty of a timing measurement used for positioning of a wireless device are disclosed. The method includes estimating a timing measurement uncertainty, and determining if an uncertainty reducing measurement is available. If an uncertainty reducing measurement is available, the method also comprises determining a timing measurement uncertainty based on the estimated timing measurement uncertainty and the uncertainty reducing measurement.

Abstract: A system and method for providing coherent sources for phased arrays are provided. One method includes providing a plurality of transceivers configured to transmit signals and defining an array of nodes. The method also includes providing a plurality of beacons at different frequencies to one of aim or focus phase coherent energy generated by the transmitted signals from the plurality of transceivers, wherein the phase coherent energy is transmitted at a direction and a frequency determined with phase conjugation and independent of the location of the plurality of beacons.