Abstract: An asset's TCU, or a mobile device coupled thereto, receives and stores geographical boundary definitions to a memory. A processor uses the boundary definition to determine an initial-location boundary based on the definition and the current location of the TCU at the time it received the boundary request message. As the TCU's GPS unit generates location information, the processor retrieves the initial-location boundary definition from the memory and compares the current location from the GPS receiver to it according to an algorithm. If the processor determines that the current location of the vehicle has crossed the boundary, the processor generates an alert message, which may be an e-mail, SMS, telephonic, internet, IM, or other electronic message indicating that an asset crossed the boundary, and sends it wirelessly using a transceiver to a central computer for further processing, or directly to another device, according to a notification destination identifier.

Abstract: A bus stop sign capable of providing detailed bus schedules includes a storage unit, a detecting unit, a communicating unit, and a control unit. The storage unit pre-stores a table recording identifications of a plurality of mobile terminals, identifications of a plurality of bus terminals, and stop information of the bus stop sign along bus routes of the bus terminals. If the identifications of the mobile terminals obtained by the detecting unit match one or more identifications recorded in the table, the control unit obtains identifications of bus terminals recorded in the table corresponding to the obtained identifications, and controls the communicating unit to transmit the obtained identifications to the server. The server determines the current location of the nearest bus terminal travelling toward the bus stop sign and feeds back the current location of the nearest bus terminal to the mobile terminal. A related sever is also provided.

Abstract: A rebinning device includes a rebinning engine that transforms signal data from a first format to a second format with vectorized binning. Moreover, a data storage operably coupled to the rebinning engine stores the signal data in the second format. The rebinning device may optionally includes a capturing engine that captures the signal data in the first format and a rendering engine that renders the signal data in the second format.

Abstract: The disclosure relates to a method for decoding a received signal in a MIMO communication system and in at least one layer, each layer carrying at least one data symbol belonging to a signal constellation. The method includes, for one of the at least one layer, a maximum likelihood detection step. This step includes: selecting one candidate value for the data symbol of the layer, and determining the Euclidian distance between the received signal Y and the data signal transmitted using said candidate value multiplied by said channel matrix H, weighted by the inverse of a noise covariance matrix C such as ?Y??iHixi?C?12 expressed as: ?i?n?C?12|xi|2?2(HiHC?1Y?0.5?j?i,nHiHC?1Hjxj)xi*+?Hn?C?12|xn|2?2(HnHC?1Y??j?nHnHC?1Hjxj)xn*=?i?n?iR(xi)2?2?iRxi+?nR(xn)2?2?nRxn+?i?n?iI(?xi)2?2?iI?xi+?nI(?xn)2?2?nI?xn. The terms depending on ?k are computed by adding to each of them a predetermined constant depending on the size of the constellation of the layer k, called a constellation dependent constant.

Abstract: A method is provided. An analog signal is received. The analog input signal is compared to first and second reference signals to generate a first comparison result, and the first comparison result and a first time stamp corresponding to the first comparison result are registered. A first portion of a digital signal is generated from the first comparison result. If the comparison result remains substantially the same for a predetermined interval, an ADC is enabled to generate a second comparison result at a sampling instant. A second time stamp that corresponds to the sampling instant is generated. The second comparison result and a second time stamp corresponding to the first comparison result are registered, and a second portion of the digital signal is generated from the second comparison result.

Abstract: A method is provided. An analog signal is received. The analog input signal is compared to first and second reference signals to generate a first comparison result, and the first comparison result and a first time stamp corresponding to the first comparison result are registered. A first portion of a digital signal is generated from the first comparison result. At least one of the first and second reference signals is adjusted. A second comparison result is generated if the analog signal reaches an adjusted one of the first and second reference signals within a predetermined interval, and a second portion of the digital signal is generated from the second comparison result.

Abstract: A pipeline ADC (analog-to-digital converter) (14) includes a residue amplifier (7) for applying a first residue signal (Vres1) to a first input of a residue amplifier (11A) and to an input of a sub-ADC (8) for resolving a predetermined number (m) of bits and producing a redundancy bit in response to the first residue signal. A level-shifting MDAC (9A) converts the predetermined number of bits and the redundancy bit to an analog signal (10) on the a second input of the residue amplifier, which amplifies the difference between the first residue signal and the analog signal to generate a second residue signal (Vres2). The MDAC causes the residue amplifier to shift the second residue signal back within a predetermined voltage range (±Vref/2) by the end of the amplifying if the second residue signal is outside of the predetermined voltage range.

Abstract: In an ultra-wideband communication system, a 1-trit ternary analog-to-digital converter (“ADC”) having dynamic threshold adaption and providing an output in ternary form [+1, 0, ?1]. The ternary ADC includes a pair of 1-bit binary ADCs, one being configured in a non-inverting form, and one being configured in an inverting form. Each binary ADC includes an feedback network mechanism, thereby allowing for simultaneous and independent adaptation of the pair of thresholds, compensating for the effects of any DC offset that may be present. The use of a trit-based ternary encoding scheme improves system entropy.

Abstract: Various pipeline ADCs are disclosed that substantially compensate for interference or distortion that results from imperfections with various ADC modules of the pipeline ADCs. The pipeline ADCs include various ADC stages and various compensation stages that are coupled to the various ADC stages. The various ADC stages convert their corresponding analog inputs from an analog signal domain to a digital signal domain to provide various digital output signals and various analog residual signals to subsequent ADC stages. The various compensation stages compensate for interference or distortion that is impressed onto the various analog residual signals which results from imperfections within previous ADC stages.

Abstract: One or more techniques for buffer offset modulation or buffer offset cancelling are provided herein. In an embodiment, an output for a sigma-delta analog digital converter (ADC) is provided using an output of a first chop-able buffer (FB) and an output of a second chop-able buffer (SB). For example, the output of the FB is associated with a first offset, the output of the SB is associated with a second offset, and the output of the ADC includes an ADC offset associated with the first offset and the second offset. In an embodiment, buffer offset modulation is provided by modulating the ADC offset using an offset rotation. In an example, the offset rotation is based at least in part on a reference clock and the output of the ADC. The buffer offset modulation mitigates the first offset or the second offset, where such offsets are generally undesired.

Abstract: An analog to digital converter including a low pass filter element, a quantizer, and a digital to analog converter provide in a feedback path. The low pass filter element is configured to filter an analog input signal. The quantizer is configured to receive an analog output signal that is based on the filtered analog input signal and convert the analog output signal to a digital output signal. The digital to analog converter is configured to generate an analog feedback signal based on the digital output signal and selectively inject or absorb current associated with the feedback path to reduce noise associated with the digital to analog converter. The analog feedback signal is combined with the analog input signal at an input of the low pass filter element.

Abstract: A sampling circuit includes a continuous section which is a circuit for transmitting a continuous signal; a digital section for transmitting a signal which is sampled and quantized; and a sampling and holding section for transmitting a signal which is sampled but not quantized between the continuous section and the digital section. The sampling and holding section includes capacitors for accumulating charge generated by an input signal and plural switches for accumulating the charge in the capacitors. The plural switches receive plural clock signals having different operation timings and perform an ON/OFF operation in response to the supplied clock signals.

Abstract: An A/D converter comprising: a sampling circuit including a continuous section, a sampling and holding section for intermittently sampling an input signal based on an analog signal input from the continuous section to hold and transfer the sampled signal, and a digital section for outputting a signal transferred from the sampling and holding section as a digital signal; and a control circuit for supplying a clock signal in which jitter is not added to the continuous section and supplying a clock signal in which the jitter is added to the sampling and holding section.

Abstract: A system and method is disclosed for a digital to analog converter which includes an interpolation filter to up-sample a digital signal, a noise shaping modulator to suppress in-band quantization errors due to digital pulse width modulation and truncation errors, and a hybrid finite impulse response filter/digital to analog converter coupled to a reconstruction filter which outputs the analog signal.

Abstract: Embodiments of a digital-to-analog conversion system that utilizes a specialized clock signal to reshape an analog impulse response of a digital-to-analog converter (DAC) are disclosed. Preferably, a shape of the specialized clock signal is such that Nyquist images resulting from digital-to-analog conversion are controlled in a desired manner. In one embodiment, the digital-to-analog conversion system includes a DAC that converts a digital input signal into an analog output signal. A specialized clock signal is applied to the analog output signal of the DAC such that an analog impulse response of the DAC is reshaped according to a shape of the specialized clock signal, thereby providing a modified analog output signal. The specialized clock signal reshapes the analog impulse response of the DAC such that Nyquist images resulting from digital-to-analog conversion are controlled in a desired manner.

Abstract: A system and method is disclosed for a digital input Class D amplifier which includes an interpolation filter to up-sample a digital signal, a noise shaping modulator to suppress in-band quantization errors due to digital pulse width modulation and truncation errors, and a hybrid finite impulse response filter/digital to analog converter coupled to an analog input Class D amplifier with digital pulse width modulation control loop. The hybrid finite impulse response filter/digital to analog converter uses N-taps implemented digitally and N-tap weights implemented in analog using resistors.

Abstract: Systems and techniques for performing binary divarication digital-to-analog conversion are described. A described converter includes voltage range adjusters arranged in series to convert a digital sequence to an analog representation, each of the adjusters being responsive to a respective bit of the digital sequence, and a combiner. The first adjuster produces first high and low output voltages based on first high and low input voltages and a most significant bit value of the digital sequence. The last adjuster produces last high and low output voltages based on last high and low input voltages and a least significant bit value of the digital sequence. The last high and low input voltages are responsive to the first high and low output voltages as modified by any of zero or more intermediate voltage range adjusters. The combiner produces an analog output signal based on the last high and low output voltages.

Abstract: A system and method is disclosed for a digital to analog converter which includes an interpolation filter to up-sample a digital signal, a noise shaping modulator to suppress in-band quantization errors due to digital pulse width modulation and truncation errors, and a hybrid finite impulse response filter/digital to analog converter coupled to a Class D delta-sigma pulse width modulation control loop.

Abstract: A system and method is disclosed for a digital to analog converter which includes an interpolation filter to up-sample a digital signal, a noise shaping modulator to suppress in-band quantization errors due to digital pulse width modulation and truncation errors, and a hybrid finite impulse response filter/digital to analog converter coupled to a reconstruction filter which outputs the analog signal. The hybrid finite impulse response filter/digital to analog converter uses N-taps implemented digitally and N-tap weights implemented in analog using switched capacitors.

Abstract: A reception device and corresponding method for maintaining a high dynamic range of an AD converter circuit and preventing excessive input to the AD converter circuit is disclosed. For example, a reception device includes a variable gain amplifier circuit that amplifies an input analog signal with a gain controlled by a predetermined control signal, an analog-to-digital converter circuit an overload detector circuit with the same frequency characteristic as the analog-to-digital converter circuit. The overload detector circuit outputs a signal according to a comparison between a level of a signal input to the analog-to-digital converter circuit and a predetermined threshold. The signal that lowers the gain of the variable gain amplifier circuit more greatly is selected out of the signal from the overload detector circuit and another signal, and the gain of the variable gain amplifier circuit is controlled on the basis of the selected signal.

Abstract: A reference voltage is maintained stable against disturbance noise and self-noise of an internal circuit. A reference voltage stabilizer circuit for stabilizing the reference voltage to be supplied through at least one of first or second signal lines includes a preceding-stage circuit including a capacitive path connected between the first and second signal lines; and a subsequent-stage circuit including a resistive path connected between the first and second signal lines, and a resistive circuit inserted, between the capacitive path and the resistive path, into one of the first or second signal lines through which the reference voltage is supplied.

Abstract: An apparatus is provided. A comparison circuit is configured to receive an analog signal. A reference circuit is coupled to the comparison circuit and is configured to provide a plurality of reference signals to the comparison circuit. A conversion circuit is coupled to the comparison circuit and is configured to detect a change in the output of the comparison circuit. A time-to-digital converter (TDC) is coupled to the comparison circuit. A timer is coupled to the comparison circuit. A rate control circuit is coupled to the conversion circuit. An output circuit is coupled to the rate control circuit and the TDC, where the output circuit is configured to output at least one of a synchronous digital representation of the analog signal and an asynchronous digital representation of the analog signal.

Abstract: An analog-to-digital converter includes a comparison unit that outputs a result obtained by comparing a voltage of an input node with a comparison voltage; 1st to Nth capacitors having one ends connected to the input node, respectively; and 1st to N?1th voltage selection units corresponds to the 2nd to Nth capacitors, respectively and applies one of a voltages of a 1st node, a 2nd node, and the comparison voltage to the other ends of the corresponding capacitors. An input signal is sampled to the input node, the 1st to N?1th voltage selection units select one of the voltages of the 2 nodes and convert a part of the input signal into a 1st digital signal, and the 1st to N?1th voltage selection units select one of the voltages of the 2 nodes and convert the remaining part of the input signal into a 2nd digital signal.

Abstract: Systems and methods for protecting an airborne platform against collisions are provided. One system includes FMCW radar sensors including transmitting antennae, means for receiving signals from echoes and for processing and digitizing same, and means for sending a central unit data representing said digital signals via a dedicated point to point link. The central unit includes means for processing said data to detect obstacles, means for calculating parameters for each obstacle including its radial velocity, distance range and azimuth, and means to transmit an avionic system of said platform data representing said detected obstacles and parameters. The system further includes means for guaranteeing that said emitted signals are shifted in time to create a shift in frequency guaranteeing that the radar sensors operate in the whole frequency band without perturbing each other.

Abstract: A small unmanned aerial system (sUAS) is used for remotely detecting concealed explosive devices—such as buried or otherwise hidden improvised explosive devices (IED)—and exploding or disarming the device while an operator of the sUAS, or other personnel, remain at a safe distance. The sUAS system can be operated at an extended, e.g., greater than 100 meters, standoff from the detection apparatus, explosive, and potential harm and may be operated by a single member of an explosive ordnance disposal (EOD) team. The sUAS may be implemented as an easy-to-operate, small vertical take-off and landing (VTOL) aircraft with a set of optical, thermal, and chemical detection modules for detecting an IED by aerial surveillance, confirming the existence of explosives, and providing options for detonating the IED electrically or by delivery of a payload (e.g., object or device) to neutralize the IED while maintaining the sUAS itself safe from harm.

Abstract: A helicopter collision-avoidance system is disclosed. An exemplary system includes at least one lamp, such as a light emitting diode (LED) lamp, an incandescent lamp, a halogen lamp, an infrared lamp, or the like; a radar emitter configured to emit a radar signal; a radar detector configured to receive a radar return signal associated with reflections of the emitted radar signal that are reflected from an object; and a radio frequency (RF) system configured to wirelessly transmit radar information associated with the received radar return signal to a radar information receiver configured to receive the wirelessly transmitted radar information. The light module is located at one of a plurality of light positions on an external surface of a helicopter.

Abstract: A ground obstacle collision-avoidance system includes a plurality of radar sensor modules that each receive at a radar detector radar return signals corresponding to reflections of the emitted signal from a ground obstacle, and transmits radar information associated with the received radar signal reflections reflected from the ground obstacle, wherein each of the plurality of radar sensor modules are uniquely located on a surface of an aircraft that is at risk for collision with a ground obstacle if the aircraft is moving; a gateway unit that receives the radar information transmitted from the radar sensor module and transmits information associated with the received radar information; a processing system configured to determine a distance from the installation aircraft to a detected ground object detected; and a display configured to present a plan view indicating an aircraft icon and a graphical ground obstacle icon that is associated with the detected ground obstacle.

Abstract: A land-based Smart-Sensor System and several system architectures for detection, tracking, and classification of people and vehicles automatically and in real time for border, property, and facility security surveillance is described. The preferred embodiment of the proposed Smart-Sensor System is comprised of (1) a low-cost, non-coherent radar, whose function is to detect and track people, singly or in groups, and various means of transportation, which may include vehicles, animals, or aircraft, singly or in groups, and cue (2) an optical sensor such as a long-wave infrared (LWIR) sensor, whose function is to classify the identified targets and produce movie clips for operator validation and use, and (3) an IBM CELL supercomputer to process the collected data in real-time. The Smart Sensor System can be implemented in a tower-based or a mobile-based, or combination system architecture. The radar can also be operated as a stand-alone system.

Abstract: A surveillance system includes a multi-propeller aircraft having a main propeller and a plurality of wing unit propellers; a housing that houses the main propeller and the wing unit propellers; an optical video camera; an ultra-wideband (UWB) radar imaging system; a control system for controlling flight of the multi-propeller aircraft from a remote location; and a telemetry system for providing information from the optical camera and the ultra-wideband (UWB) radar imaging system to a remote location.

Abstract: An object detection apparatus includes: a first radar configured to measure first positional information regarding a first object existing in a first scan range; a second radar configured to measure second positional information regarding a second object existing in a second scan range on the basis of second reflected wave of second wave radiated onto the second scan range including the first region and a second region, the second wave being radiated in such a way as to scan the first region in a direction opposite a direction in which the first radar radiates the first wave; and a processor configured to detect a third object existing in the first region on the basis of the first positional information and the second positional information.

Abstract: A signal processing device is provided. The device includes an echo signal input unit for receiving echo signals resulted from transmission signals reflected on an object. The transmission signals are transmitted from a transmission source at transmission timings at predetermined time intervals, at least one of the transmission timings shifted from the other timings in time. The device includes a complex reception signal generator for generating complex reception signals, a phase calculator for calculating a phase change amount of the complex reception signals with respect to a reference phase, a phase corrector for phase-correcting the complex reception signals and outputting the corrected signals, and a Doppler processor for performing Doppler processing on the corrected signals and outputting the Doppler-processed signals as Doppler echo signals of the object.

Abstract: A tag decides a response based on a plurality of queries received from a reader, determines whether to transmit the response, transmits the response to the reader according to the results of the determination, and transmits a message authentication code including communication content to the reader. The reader calculates a consumed time period which is the time difference between a transmission time at which the queries are transmitted and a reception time at which the response is received, calculates an average consumed time period of the consumed time period, and measures a distance to the tag based on the average consumed time period. Accordingly, it is possible to check an attacker's intervention with a high probability, thereby improving distance measurement performance. Also, the tag may efficiently perform computing and communication.

Abstract: In an in-vehicle radar device, as a vertical azimuth which is an azimuth of a target in a direction perpendicular to a ground surface, a real image vertical azimuth which is an azimuth of a real image existing above ground is calculated from a reflected wave generated when a transmission signal transmitted from a transmission antenna reflected from the target, and a virtual image vertical azimuth which is an azimuth of a virtual image existing underground is calculated from a reflected wave generated when the transmission signal transmitted from the transmission antenna is reflected from the target and reflected again from the ground surface. Next, in the in-vehicle radar device, an angle difference between the real image vertical azimuth and the virtual image vertical azimuth which are calculated is calculated, and a height of the target from the ground surface is calculated using the calculated angle difference.

Abstract: A transmission beam control unit 8 changes a main beam direction of a radar transmission beam every predetermined number of transmission periods. A radar transmitting unit Tx transmits a radar transmission signal using the radar transmission beam of which the main beam direction has been changed. In a radar receiving unit Rx, an estimation range selection unit 22 selects an estimation range of the direction of arrival of a reflected wave signal by limiting the estimation range to the approximate transmission beam width on the basis of the transmission beam width of the radar transmission beam and the output from the transmission beam control unit 8. The direction-of-arrival estimation unit 23 estimates the direction of arrival of the reflected wave signal on the basis of phase information between a plurality of antennas according to the selected range.

Abstract: X-band and P-band synthetic aperture radars are used to simultaneously gather swaths of reflected radar data over a specific area simultaneously. The P-band is used to penetrate surface clutter that may be on the top of an ice formation as well as to penetrate an ice mass. X-band is used to map surface clutter on the top of an ice formation as well as to map the top of snow that may appear on an ice formation. Digital elevation maps of the top of the snow or ice clutter, the top of the ice, and the bottom of the ice and or ice thickness are constructed. By summing these various digital elevation maps a measurement of the thickness of sea ice can be determined. Further analysis of DEM, MAG and CRV layers provides an indication of the quality of the ice, for example cracks and pressure ridges, and its weak points.

Abstract: A navigation system includes first receiver receiving satellite signals, second receiver receiving differential correction data from ground receivers, and processing device coupled to receivers.

Abstract: Method, apparatus, and programs for synchronizing navigation data. Data synchronization is established between a receiver and a navigation device based on matching of a header of navigation data. The receiver receives the navigation data from the navigation device. If, subsequently, the data synchronization is interrupted, information related to the data synchronization from the receiver is retrieved. The data synchronization is then re-established between the receiver and the navigation device based on the retrieved information.

Abstract: Method, apparatus, and programs for synchronizing navigation data. A distance between a navigation device and a receiver is estimated. The receiver receives navigation data from the navigation device. A sending time of the navigation data sent from the navigation device is then determined based on the estimated distance between the navigation device and receiver. Synchronization information is computed based on the sending time of the navigation data. The synchronization information is used for synchronizing the navigation data.

Abstract: Method, apparatus, and programs for synchronizing navigation data. A first distance between a first navigation device and a receiver and a second distance between a second navigation device and the receiver are estimated. The receiver receives first and second navigation data from the first and second navigation devices, respectively. Based on a first sending time of the first navigation data sent from the first navigation device and the first and second distances, a second sending time of the second navigation data sent from the second navigation device is then determined. Synchronization information of the second navigation device is computed based on the second sending time of the second navigation data. The synchronization information is used for synchronizing the second navigation data received at the receiver.

Abstract: System and method for locating a satellite signal receiver are disclosed. The system includes a channel opening module, a signal processing module, and a positioning module. The channel opening module is configured for opening a predetermined number of channels based on a priority schedule. The signal processing module is configured for capturing and tracking satellite signals via the opened channels, and demodulating the tracked satellite signals to obtain corresponding satellite data. The positioning module is configured for determining a position of the satellite signal receiver based on the satellite data.

Abstract: A satellite signal receiver and a method for updating ephemeris information thereby are disclosed. The receiver includes an instruction module, a signal processing module, and an update module. The instruction module is configured to send an instruction for updating ephemeris information at a set time interval. The signal processing module is configured to obtain corresponding satellite data. The update module is configured to update the ephemeris information according to the obtained satellite data in response to the instruction for updating ephemeris information.

Abstract: The invention relates to a method for tracking the carrier phase of a signal received from a satellite by a carrier using a carrier loop of the carrier phase, said signal being acquired by a navigation system of the carrier, said navigation system including a receiver for location by radio navigation, and a self-contained unit, wherein the receiver is suitable for acquiring and tracking the phase of the carrier of the signal from the satellite.

Abstract: An object locator system for locating an object of interest in a scene. The locator system includes: a) a body mounted pedestrian localization unit worn by an operator; b) a hand-held rangefinder configured to be grasped by the operator; c) a pose sensor for estimating relative position and orientation of the hand-held rangefinder relative to the localization device; and d) a computer control system coupled to the pedestrian localization unit, the rangefinder, and the pose sensor, the computer control system being programmed to compute a relative location of the object with respect to the body worn localization unit using range data from the rangefinder and relative pose from the pose sensor, and transform the relative location to a global location using data from the pedestrian localization unit.

Abstract: Methods and apparatus to provide assistance data for satellite navigation in a wireless communication device are disclosed. Processing circuitry in the wireless communication device determines whether to obtain assistance data for navigation based on a set of criteria. The set of criteria include one or more of a property of a geographic region in which the wireless communication device operates, a satellite signal quality estimate measured by the wireless communication device, and a user setting of the wireless communication device. When the set of criteria indicates that assistance data for navigation is beneficial for satellite navigation in the wireless communication device, the processing circuitry obtains one or more sets of assistance data. The processing circuitry configures operation of the wireless communication device for navigation based at least in part on the one or more sets of assistance data obtained.

Abstract: A computing device may rely on GPS and IR communication to determine its current location. The limits of GPS may prevent it from reliably providing location data to the computing device in a variety of situations such as in downtown metropolitan areas, geographic regions with thick canopies, in buildings, and the like. As a result, a second communication technique may also be used to provide location data to the computing device. For example, an IR transmitter may transmit location data to the computing device which, in turn, uses the location data to identify its current location. In addition, the computing device may receive or transmit supplemental data using the second communication technique for, e.g., synchronizing the computing device to a real-time event happening at the identified location or providing the location of the device to a central computing system.

Abstract: A tracking and mapping system for outdoor use includes a first GPS locator located either at a base station or on a hunting accessory such as an arrow. The system also includes a second GPS locator for identifying a user's location, and an electronic display unit for communicating with a global positioning satellite and displaying a map showing icons representing locations of the first and second GPS locators. The second OPS locator may be embedded in the electronic display unit, which may be a mobile wireless handheld device, a tablet or other portable computer having wireless connectivity. The electronic display unit maps the present location of each of the GPS locators in relation to a direction such as north, south, east or west. Optionally, separate GPS locators may be placed at a base station and in an arrow. A method of using the tracking and mapping system is also described.

Abstract: A method of communicating corrections for information related to satellite signals among global navigation satellite system (GNSS) receivers is described. The method includes at a first GNSS device determining a component of position of a satellite. The component is then divided by a first value to thereby obtain an integer value and a remainder value, and the only the remainder value is transmitted from the first GNSS device to the second GNSS device. Knowing the first value, the second GNSS device calculates the component of position.

Abstract: Methods and apparatuses to assist a global positioning system (GPS) module to determine GPS position estimates for a wireless communication device is disclosed. Processing circuitry in the wireless communication device determines a potential or an actual inaccuracy in a GPS position estimate obtained from a GPS module. The processing circuitry obtains a set of map vector data stored in or associated with the wireless communication device. The processing circuitry determines a location estimate of the wireless communication device based on at least a portion of the set of map vector data. The processing circuitry provides the location estimate to the GPS module and obtains an updated GPS position estimate from the GPS module, the updated GPS position estimate based at least in part on the location estimate provided to the GPS module.

Abstract: Systems and methods for detecting and displaying cycle slips are provided. In one example method, a first L1 signal and a second L2 signal may be received. The coarse/acquisition code from the L1 signal may be extracted and may be monitored to detect a phase shift in the code. In response to detecting a phase shift in the code, a data bit of the L1 signal may be monitored for a predetermined length of time to detect a change in the data bit. A cycle slip may be detected in response to detecting a change in the data bit during the predetermined length of time. In another example, a cycle slip may be detected in response to detecting a change between a phase of the L1 signal and a phase of the L2 signal.

Abstract: An offset estimator (e.g., a time delay, a spatial image offset, etc.) makes use of a transform approach (e.g., using Fast Fourier Transforms). The sparse nature of a cross-correlation is exploited by limiting the computation required in either or both of the forward and inverse transforms. For example, only a subset of the transform values (e.g., a regular subsampling of the values) is used. In some examples, an inverse transform yields a time aliased version of the cross-correlation. Further processing then identifies the most likely offset of the original signals by considering offsets that are consistent with the aliased output.