Abstract: An arrangement of M signal generators in a global navigation satellite signal baseband chip for obtaining a sequential chip correlation array is provided. The sequential chip correlation array generates M×N code bit sequences, M in-phase and M quadrature-phase carrier mixed signals. The M signal generators are arranged consecutively. A programmable parameter is created for providing a spacing of TC between each N code bit sequences. A first carrier and code generator is provided within each signal generator for generating an in-phase and a quadrature-phase component of a first carrier signal, and N code bit sequences. The first carrier and code generators within adjacently arranged signal generators are programmed with same code chip offset, different carrier signal frequency, different code frequency, and different code phase offset. M in-phase and M quadrature-phase carrier mixed signals, and N code bit sequences are generated by the M signal generators based on the programmable parameter.

Abstract: According to one embodiment, a system for generating a signal includes a monocycle generator, one or more temporal modulators, and a pulse shaper. The monocycle generator generates monocycles that form a signal comprising pulses, where a pulse corresponds to one or more monocycles. The temporal modulators provide instructions the monocycle generator to create a specific spectral response in the signal. A pulse shaper individually modulates at least one monocycle of the monocycles corresponding to a pulse to shape the pulse.

Abstract: An imaging device is provided, comprising: a decorrelation circuit configured to receive K initial imaging signals and to perform a decorrelation operation on K initial imaging signals, respectively, to generate K decorrelated imaging signals; Kh wavelet decomposition circuits configured to perform K wavelet decomposition operations on the K decorrelated imaging signals, respectively, to generate K decomposed imaging signals; K quantization circuits configured to perform K quantization operations on the K decomposed imaging signals, respectively, to generate K quantized imaging signals; and a bit multiplexer configured to generate a compressed bit stream based on the K quantized imaging signals; a data line configured to pass the compressed bit stream; and a decompressor module configured to convert the compressed bit stream into K recovered imaging signals corresponding to the K initial imaging signals, wherein K is an integer greater than 1.

Abstract: A system and method for determining whether a wireless device has transmitted one or more forged satellite measurements. An estimated location of the wireless device may be determined as a function of information from a cellular network. Acquisition assistance data may be determined for a first set of satellites as a function of the estimated location, the assistance data including an uncertainty window. If measured code phase information in the satellite measurements substantially correlates to the uncertainty window, then the wireless device may be transmitting forged satellite measurements.

Abstract: In general, the subject matter described in this specification can be embodied in methods, systems, and program products. Data representing a plurality of power management profiles for a battery-operated wireless computing device are stored on the device. The power management profiles correspond to different power consumption levels. Each power management profile defines a feature for determining a geographic location of the device from among a plurality of features that are available for determining the geographic location of the device, and a frequency for employing the feature to determine the geographic location of the device. A first battery level of the device is determined. If the determined battery level is lower than a first predetermined amount, the device switches from a first power management profile having a first consumption level to a second power management profile having a second consumption level that is lower than the first consumption level.

Abstract: Provided are an apparatus and method for controlling a radiation direction. The apparatus includes parasitic elements disposed in proximity to the antenna, wherein each of the parasitic elements comprises an antenna; a first portion that is inclined with respect to a prepared ground surface at a first angle and a second portion that is inclined with respect to the first portion at a second angle; a lumped element having a variable reactance, which is disposed on each of the first and second portions; and a determination unit controlling the reactance of the lumped element so as to determine the radiation direction of the antenna. By using the apparatus and the method, the antenna has various radiation directions.

Abstract: A method and system for assisting mobile stations to locate a satellite use an efficient messaging format. A server computes a correction between coarse orbit data of a satellite and precise orbit data of the satellite. A coordinate system is chosen such that variation of the correction is substantially smooth over time. The server further approximates the correction with mathematical functions to reduce the number of bits necessary for transmission to a mobile station. The mobile station, upon receiving the coefficients, evaluates the mathematical functions using the coefficients and a time of applicability (e.g., the current time), converts the evaluated result to a standard coordinate system, and applies the conversion result to the coarse orbit data to obtain the precise orbit data.

Abstract: In general, the subject matter described in this specification can be embodied in methods, systems, and program products. Data representing a plurality of power management profiles for a battery-operated wireless computing device are stored on the device. The power management profiles correspond to different power consumption levels. Each power management profile defines a feature for determining a geographic location of the device from among a plurality of features that are available for determining the geographic location of the device, and a frequency for employing the feature to determine the geographic location of the device. A first battery level of the device is determined. If the determined battery level is lower than a first predetermined amount, the device switches from a first power management profile having a first consumption level to a second power management profile having a second consumption level that is lower than the first consumption level.

Abstract: For amending navigation data of a global navigation system, navigation signals are received from a space vehicle, and a predicted clock phase offset of the clock signal sent from the space vehicle is estimated and stored in a memory. The clock phase offset difference between the current estimated clock phase offset and a previously estimated clock phase offset times (T1) is then computed and stored. An earlier computed phase offset difference between a previously estimated clock phase offset and a further previous estimation for said clock phase offset is obtained, wherein the time interval between the current measurement epoch and second earlier epoch is at least T1. The difference between the computed clock phase offset differences is derived, and compared with a given threshold value. If the latter difference is greater than the given threshold value, an integrity risk signal is generated and transmitted to other devices for position determination.

Abstract: An exemplary radio-based navigation system uses a small multimode direction-finding antenna and a direction-finding receiver capable of determining platform position, velocity, attitude, and time while simultaneously providing protection against narrowband and broadband sources of interference. Global Navigation Satellite System (GNSS) signals such as those from the Global Positioning System (GPS) provide attitude measurements with a compact multimode direction-finding antenna (e.g., a small two-arm spiral with improved angle-of-arrival performance over the entire hemisphere enhanced through the use of a conductive vertical extension of the antenna ground plane about the antenna perimeter and/or conductive posts placed evenly around the antenna perimeter) which provides simultaneous protection against jammers. The multimode spiral may be treated as an array of rotationally-symmetric antenna elements.

Abstract: A global navigation satellite system (GNSS) enabled mobile device may be operable to assert one of autoblank signals when RF interference is detected in received GNSS signals for one of consecutive first time windows. The asserted autoblank signals are monitored by the GNSS enabled mobile device over time intervals corresponding to consecutive second time windows and a rate at which the autoblank signals are asserted for each of the consecutive second time windows is determined by the GNSS enabled mobile device based on the monitoring. The GNSS enabled mobile device may be operable to determine whether to blank processing of the received GNSS signals based on the determined rate. The autoblank signals may be asserted by the GNSS enabled mobile device based on a number of the received GNSS signals whose absolute signal levels exceed a signal level threshold for the first time window.

Abstract: The location of a land-based radio frequency (RF) emitter is determined from an airborne platform. RF signaling is received from the RF emitter via first and second antennas. In response to the received RF signaling, signal samples for both antennas are produced and processed to determine the location of the RF emitter.

Abstract: A system and method for providing a spectrally compact modulation of a tracking signal for directional beam scanning systems is presented. The system and method scans a tracking signal to produce a modulation of the tracking signal. When an impairment is anticipated, the system and method modifies the scan path to avoid the impairment and maintains the spectral compactness of the modulation of the tracking signal.

Abstract: Requests for location fix for a mobile device, received from one or more Location Based Service (LBS) applications are queued in a queue in the mobile device. Based on information in a first queued request, the mobile device runs a location engine in a first fix mode to obtain a location fix for the mobile device, for a response to the first request. While the location engine is running to obtain the fix for the response to the first request, the mobile device analyzes information in a second queued request, to determine a second fix mode for response to the second request. Based on a comparison of the first and second fix modes, the mobile device may change the information in the second request to correspond to the first fix mode, before output of the second request from the queue to the location engine.

Abstract: A method and apparatus for determining stream weights is provided herein. During operation, an uplink direction of arrival (DOA) and a downlink direction of departure (DOD) calibration procedure is implemented using uplink signals and GPS information from a subset of mobiles without the need of calibration circuitry at the base. Because the presented calibration procedure needs no new hardware it can be deployed in existing deployments with only a soft-ware upgrade.

Abstract: In an overlay, U-TDOA-based, Wireless Location System, LMUs typically co-located with BTSs, are used to collect radio signaling both in the forward and reverse channels. Techniques are used to compensate for sparse LMU deployments where sections of the U-TDOA service area are uplink demodulation or downlink beacon discovery limited.

Abstract: Embodiments provided herein recite methods and systems for an accuracy estimator for a position fix. In one embodiment, a solution receiver for receiving a code solution and at least one additional solution from a different solution technique is utilized. In addition, a table of metric values comprising an associated accuracy estimate for at least one characteristic of each of the code solution and the at least one additional solution is also utilized. A comparator compares the code solution and the at least one additional solution with the table of metric values. In addition, a solution orderer orders the at least one additional solution above or below the code solution dependent on whether the at least one additional solution is within a pre-defined offset distance threshold. If the at least one additional solution is outside of the distance threshold, the code solution is chosen as the final solution.

Abstract: Embodiments of an improved assisted global positioning system (GPS) method and system are described. Wireless access points send assistance data to GPS receivers that are integrated into cellular chipsets and other chipsets. The access points may also act as fixed location references for differential GPS (DGPS) mobile stations. Errors caused by multipath travel of the GPS signals are reduced by using fixed location reference receivers.

Abstract: A wireless device including a transceiver that utilizes a power supply is described. The wireless device includes a Global Positioning System (“GPS”) section having a plurality of GPS subsystems and a power controller in signal communication with the power supply and GPS section, wherein the power controller is configured to selectively power each GPS subsystem from the plurality of GPS subsystems.

Abstract: A method for beamforming in a communication system includes receiving a plurality of signals via a plurality of antennas, where the plurality of signals corresponds to at least one known training signal, generating a respective one of a plurality of different antenna weight vectors to be applied to the plurality of antennas as each of the plurality of signals is received, where each of the plurality of antenna weight vectors is a respective base vector of a unitary matrix, and generating a receiver antenna weight vector based on at least the received plurality of signals, the plurality of different antenna weight vectors, and the at least one known training signal.