SIRF TECHNOLOGY, INC. Patent applications |
Patent application number | Title | Published |
20130072122 | SYSTEMS AND METHODS FOR CHANNEL PAIRING A TRANSMITTER AND A RECEIVER - Systems and methods for channel pairing a transmitter and a receiver are provided. In this regard, a representative method, among others, includes selecting a channel in a radio frequency (RF) band; transmitting a carrier and alert tone on the selected channel in the RF band; responsive to detecting the transmitted carrier and alert tone, demodulating the carrier and alert tone on the selected channel in the RF band and producing the demodulated alert tone; and responsive to detecting the produced alert tone, using the selected channel to establish a wireless link between the transmitter and receiver. | 03-21-2013 |
20130021202 | Systems and Methods of Communication in an Assisted Navigation System - Provided herein are methods and systems for efficient communication between a server and a client in an assisted navigation system. In one or more embodiments, the server transmits a set of parameters for a satellite to the client, e.g., a GPS receiver, via a wireless or wired connection. The set of parameters includes a force parameter, initial condition parameters and time correction coefficients for the satellite. The receiver uses the received parameters in a numerical integration to compute the position of the satellite at a desired time. The set of parameters needed for the integration is small. To further reduce the amount of data transmitted, reference parameters may be subtracted from the original parameters before transmission from the server. The receiver is able to reconstruct the original parameters from the received parameters and the identically computed reference parameters. The parameters may be further compressed using data compression techniques. | 01-24-2013 |
20120274427 | AUTO-TUNING SYSTEM FOR AN ON-CHIP RF FILTER - A Radio Frequency Receiver on a Single Integrated Circuit (“RFSIC”) is described. The RFSIC may include a mixer, a phase-locked loop (“PLL”) in signal communication with the mixer, and an on-chip auto-tuned RF filter in signal communication with both the mixer and PPL, such that the same PLL simultaneously tunes the frequency of the VCO and the frequency response of the auto-tuned RF filter. | 11-01-2012 |
20120191614 | SYSTEM FOR LOCATION BASED TRANSACTION SECURITY - A system for improving transaction security based on location information. The system includes a transaction processing center in communication with a first transaction device and a second transaction device. The transaction processing center includes a receiver that receives respective identification and location from at least one of the first and second transaction devices. The transaction processing center also includes a transaction processor that validates the identifications, validates the locations, and executes a transaction between the first and second transaction devices when the identifications and locations are validated. | 07-26-2012 |
20120182183 | DIFFERENTIALLY COHERENT STROBE CORRELATOR - A GPS receiver for tracking a GPS signal. The receiver generates a mixed GPS signal by mixing the GPS signal with an oscillator signal, generates a first correlation signal by correlating the mixed GPS signal with a reference signal, and generates a filtered GPS signal from the GPS signal. The receiver also generates a filtered reference signal from the reference signal, generates a second correlation signal by correlating the filtered GPS signal with the filtered reference signal, and a generates a combined correlation signal by combining the first correlation signal with the second correlation signal. The receiver tracks the GPS signal by adjusting the phase of the oscillator signal based on the combined correlation signal. | 07-19-2012 |
20120007572 | AUTO CASCODE BUCK VOLTAGE CONVERTER - A voltage converter includes a power switch having respective charging and discharging control terminals, and an output terminal coupled to a series connected inductor and capacitor. The voltage converter also includes a charging switch coupled to the charging control terminal of the power switch, a discharging switch coupled to the discharging control terminal of the power switch, and a feedback circuit coupling the power switch, charging switch and discharging switch to a node at which the capacitor and inductor are connected. During a charging phase, the charging switch couples the capacitor to the charging control terminal of the power switch, and during a discharging phase, the discharging switch couples the capacitor to the discharging control terminal of the power switch. | 01-12-2012 |
20110316741 | CONTROL AND FEATURES FOR SATELLITE POSITIONING SYSTEM RECEIVERS - Control and feature systems for processing signals from a satellite positioning system include an expert system receiver manager; a joint detection, carrier centering and bit sync acquisition subsystem; peak detection; a multi-dimensional measurement interpolation subsystem; a system for mode switching between a navigational signal; and power control module for receiver. | 12-29-2011 |
20110312336 | SATELLITE BASED POSITIONING METHOD AND SYSTEM FOR COARSE LOCATION POSITIONING - A satellite based positioning method and system including storing satellite sub-almanac data on a mobile station. Embodiments include using the sub-almanac data to take measurements and calculate a coarse position of the mobile station. Embodiments further include a location server calculating a correction to the coarse position, and the location server determining whether any sub-almanacs used to calculate the coarse position require replacement. | 12-22-2011 |
20110279318 | METHOD AND APPARATUS FOR A GPS RECEIVER CAPABLE OF RECEPTION OF GPS SIGNALS AND BINARY OFFSET CARRIER SIGNALS - A system and method capable of mitigating the migration from the current GPS system to the Galileo system and allow a single satellite system positioning receiver to process both GPS signals and Galileo signals. | 11-17-2011 |
20110275341 | IP2 CALIBRATION MEASUREMENT AND SIGNAL GENERATION - A radio frequency receiver on an integrated circuit (RFIC) includes an oscillator circuit, which generates a radio frequency (RF) oscillatory signal having a predetermined frequency that is outside of an intermediate frequency passband of the RFIC. An amplitude modulator modulates the RF oscillatory signal to produce an amplitude modulated signal which is applied to a mixer that downconverts the amplitude modulated signal. A calibration circuit receives the downconverted signal, including second order modulation (IM2) products, and, responsive to the IM2 products, generates a bias signal that is applied to the mixer to reduce the IM2 products. | 11-10-2011 |
20110205115 | Always on GPS Device - 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. | 08-25-2011 |
20110183606 | SYNCHRONIZING A RADIO NETWORK WITH END USER RADIO TERMINALS - A wireless communications device comprises a communication receiver and a positioning system receiver in the wireless mobile communication device. An absolute time signal is received at the positioning system. A network time signal is received at the communication receiver of the wireless mobile communication device. A controller is in signal communication with the position system receiver and the communication receiver. The controller is configured to determine an offset of the absolute time signal from the network time signal and generates a timing mark. The timing mark is tagged by the positioning system receiver with an internal clock value wherein the timing mark has a known relationship with the absolute time signal. A memory stores the offset of the absolute time signal from the network time signal. A transmitter in the wireless mobile communication device transmits the offset for receipt by another wireless mobile communication device. | 07-28-2011 |
20110102258 | Signal Processing System for Satellite Positioning Signals - A signal processing system for processing satellite positioning signals is described. The system comprises at least one processor and a signal processor operating under a number of operational modes. The signal processor includes at last one of a signal processing subsystem, a fast Fourier transform (FFT) subsystem, and a memory subsystem that are each dynamically and independently configurable in response to the operational modes. Further, the system includes a controller that couples to control transfer of data among the signal processing subsystem and the FFT subsystem via the memory subsystem. Configurability of the memory subsystem includes configuring the memory subsystem into regions according to the operational modes where each region is accessible in one of a number of manners according to the operational modes. | 05-05-2011 |
20110034132 | Systems and Methods for Minimizing Electromagnetic Interface - Systems and methods for minimizing electromagnetic interference are provided. A representative electronic device includes a frequency generator that generates clock signals and a computing device that selects at least one generator frequency that minimizes or eliminates electromagnetic interference based on one or more radio bands of interest. The computing device is designed to send instructions associated with synthesizing the at least one generator frequency. The electronic device further includes a frequency synthesizer that receives the generated clock signals and instructions from the frequency generator and the computing device, respectively. The frequency synthesizer synthesizes the at least one generator frequency based on the received clock signal. | 02-10-2011 |
20110029240 | HOST BASED SATELLITE POSITIONING SYSTEMS - Methods and systems consistent with the present invention provide a host based positioning system. The host based positioning system includes a tracker hardware interface that connects to a dedicated hardware space vehicle tracker. The tracker hardware interface receives positioning information from the space vehicle tracker. The host based positioning system also includes a memory that includes a GPS library having a user interface, a tracker interface, and an operating system interface. A processor runs functions provided by the interfaces. | 02-03-2011 |
20100328146 | Systems and Methods for Synthesizing GPS Measurements to Improve GPS Location Availability - There are situations where GPS signals are received from less than four satellites. In order to improve the GPS location availability, disclosed here are systems and methods for synthesizing GPS measurements, which, together with fewer than four available real GPS signals, can be used to calculate a position fix. In particular, GPS range measurements for lost satellites, which are satellites that were previously tracked but are now not tracked, are synthesized to improve GPS signal availability. The synthesized measurements are used along with real measurements to enable accurate position fix even when GPS satellite availability is poor. Different synthesized measurement generation schemes, depending on whether an INS/DR aiding system is available, are further described herein. | 12-30-2010 |
20100295623 | SYSTEMS AND METHODS FOR CALIBRATING REAL TIME CLOCK - Systems and methods for calibrating real time clock are provided. A representative receiver includes a GPS device comprising a real time clock (RTC) circuitry that generates RTC clock signals and a temperature compensated crystal oscillator (TCXO) that generates TCXO clock signals. A ratio counter circuitry receives both the RTC clock signals and the TCXO clock signals and determines a frequency ratio by comparing the RTC clock signals and the TCXO clock signals. A computing device receives the frequency ratio and estimates a current RTC frequency based on the received frequency ratio. The computing device is configured to calibrate an estimated RTC time being maintained at the RTC circuitry based on an estimated RTC frequency from a prior estimation, the current RTC frequency and an elapsed time of the RTC circuitry. | 11-25-2010 |
20100279744 | SYSTEMS AND METHODS FOR MANAGING POWER CONSUMPTION OF A TRANSCEIVER - Systems and methods for managing power consumption of a transceiver, e.g., Bluetooth, are provided. A representative transceiver includes an antenna that receives analog radio frequency (RF) signals, and a RF analog circuitry that receives and processes the analog RF signals from the antenna. An analog-to-digital converter (ADC) receives and converts the processed analog RF signals to digital RF signals. A digital circuitry includes a RF power detector that receives the digital RF signals and determines a RF power of the analog RF signals from the antenna based on the digital RF signals. A computing device instructs the RF analog circuitry to operate in low current drain RF receiver mode during page scanning and/or inquiry scanning. The computing device is designed to receive the RF power of the received analog RF signals and manages the power consumption of the transceiver based on the RF power. | 11-04-2010 |
20100273441 | SYSTEMS AND METHODS FOR TUNING AN ANTENNA FOR A FREQUENCY MODULATION TRANSCEIVER - Systems and methods for tuning an antenna for a frequency modulation (FM) transceiver are provided. A representative system includes: a network of electrical adjustable passive components that receives and sends radio frequency (RF) signals to a receiver circuitry via the network of electrical adjustable passive components. The receiver circuitry determines the received signal strength indication (RSSI) of the RF signal. The system further includes a transmitter circuitry that transmits RF signals via the network of electrical adjustable passive components, and a peak detector circuitry that receives and determines a voltage output of the RF signals from the variable capacitors. An auto-tune circuitry receives the RSSI and output value from the receiver circuitry and the peak detector circuitry, respectively. The auto-tune circuitry is configured to adjust capacitance values of at least one of the serial variable capacitor and the parallel variable capacitor based on the RSSI and the voltage output during the reception and transmission of the RF signals, respectively. | 10-28-2010 |
20100250129 | SYSTEMS AND METHODS FOR MANAGING POWER CONSUMPTION - GPS navigation devices or GPS receivers can consume less power by using a temperature recorder circuit and/or a power manager in calculating the accuracies of the GPS system time and reference frequency to improve battery life. A representative receiver includes a time reference device that generates data associated with a GPS system time, and a temperature recorder circuit that operates using the generated data from the time reference device and monitors the temperature of the time reference device while the receiver hibernates. The receiver further includes memory including a power manager that has instructions, which are processed by a processing device after the receiver wakes up. The instructions associated with the power manager include determining if the temperature recorder circuit sent a wake-up signal, reading data from the temperature recorder circuit, and adjusting parameters associated with at least one of the following: the time reference device and the temperature recorder circuit. | 09-30-2010 |
20100248678 | SYSTEMS AND METHODS FOR MANAGING POWER CONSUMPTION - GPS navigation devices or GPS receivers can consume less power by using a temperature recorder circuit and/or a power manager in maintaining the accuracies of the GPS receiver time and reference frequency to improve battery life. A representative receiver includes a time reference device and the temperature recorder circuit that operate while the receiver hibernates. The time reference device generates clock signals and the temperature recorder circuit receives and operates using the clock signals from the time reference device. The temperature recorder senses the temperature of the time reference device. The temperature recorder circuit is designed to send a wake-up signal to at least one electrical component of the receiver to wake up the electrical component of the receiver. The electrical component of the receiver includes at least one of the following: a GPS signal processing system and a frequency reference device. | 09-30-2010 |
20100151786 | Systems and Methods for Channel Pairing a Transmitter and a Receiver - Systems and methods for channel pairing a transmitter and a receiver are provided. In this regard, a representative method, among others, includes selecting a channel in a radio frequency (RF) band; transmitting a carrier and alert tone on the selected channel in the RF band; responsive to detecting the transmitted carrier and alert tone, demodulating the carrier and alert tone on the selected channel in the RF band and producing the demodulated alert tone; and responsive to detecting the produced alert tone, using the selected channel to establish a wireless link between the transmitter and receiver. | 06-17-2010 |
20100150275 | Systems and Methods for Digitizing Multiple Channels in a Receiver - Systems and methods for mitigating multipath signals in a receiver are provided. In this regard, a representative system, among others, includes a radio frequency (RF) front-end and at least one analog-to-digital converter (ADC). The RF front-end receives FM signals and down-converts the received frequency signals to intermediate frequency (IF) signals. The analog-to-digital converter (ADC) receives the intermediate frequency signals and digitizes multiple FM channels around a desired FM channel associated with the down-converted signals. The system further includes multiple sets of digital processing components that are configured to simultaneously receive and process the digitized multiple channels. The multiple sets of digital processing components include at least two parallel channel selection and demodulation paths in which the respective digitized multiple channels are processed therethrough. | 06-17-2010 |
20100141341 | Receiver Having Multi-Stage Low Noise Amplifier - A receiver having multi-stage low noise amplifier are provided. In this regard, a representative receiver, among others, includes at least one antenna and a filter that receives and filters signals from the at least one antenna. The filtered signals include a first frequency band signal and a second frequency band signal. The receiver further includes a multi-stage low noise amplifier that receives the filtered signals from the filter. The multi-stage low noise amplifier includes a first stage low noise amplifier that receives and performs impedance matching for the first frequency band signal and second frequency band signal. The multi-stage low noise amplifier further includes a second stage low noise amplifier that receives the first frequency band signal and second frequency band signal. The second stage low noise amplifier includes load resistors that switch off for the first frequency band signal and switch on for the second frequency band signal based on receiving either the first frequency band signal or second frequency band signal. | 06-10-2010 |
20100134354 | Method and Apparatus for a GPS Receiver Capable or Reception of GPS Signals and Binary Offset Carrier Signals - A system and method capable of mitigating the migration from the current GPS system to the Galileo system and allow a single satellite system positioning receiver to process both GPS signals and Galileo signals. | 06-03-2010 |
20100115379 | Error Resilience Methods for Multi-Protocol Encapsulation Forward Error Correction Implementations - Systems, devices, and methods for error detection and correction in digital communication are disclosed. One such method comprises: storing data received in TS packets into an MPE-FEC frame buffer of a receiver according to locations indicated by an MPE-FEC frame buffer write pointer; and storing reliability information regarding said data separately therefrom, said reliability information including addresses of one or more locations in said MPE-FEC frame buffer to be marked for erasure. One such device is a receiver comprising an MPE-FEC frame buffer and an FEC decoder. The FEC decoder is configured to store data received in TS packets into the MPE-FEC buffer according to locations indicated by an MPE-FEC frame buffer write pointer. The FEC decoder is further configured to store reliability information regarding the data separately therefrom, the reliability information including addresses of one or more locations in the MPE-FEC frame buffer to be marked for erasure. | 05-06-2010 |
20100039316 | System and Method for Operating a GPS Device in a Micro Power Mode - 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. | 02-18-2010 |
20090325521 | Auto-Tuning System for an On-Chip RF Filter - A Radio Frequency Receiver on a Single Integrated Circuit (“RFSIC”) is described. The RFSIC may include a mixer, a phase-locked loop (“PLL”) in signal communication with the mixer, and an on-chip auto-tuned RF filter in signal communication with both the mixer and PPL, such that the same PLL simultaneously tunes the frequency of the VCO and the frequency response of the auto-tuned RF filter. | 12-31-2009 |
20090323780 | Method and Apparatus for Mitigating the Effects of CW Interference Via Post Correlation Processing in a GPS Receiver - A positioning system receiver that mitigates the effect of continuous wave (CW) carrier interference with post correlation processing in a satellite positioning receiver, while not distorting the signal waveform or degrading receiver sensitivity and performing in low signal and dynamic interference environments. | 12-31-2009 |
20090323779 | Method and Apparatus for Mitigating the Effects of Narrowband Interfering Signals in a GPS Receiver - A positioning system receiver that mitigates narrowband interference by dynamically choosing the mitigation technique that yields the best interference mitigation capability with the least signal degradation to maximize receiver performance parameters such as receiver sensitivity, multipath resolution, and low power. | 12-31-2009 |
20090322606 | Method and Apparatus for Real Time Clock (RTC) Brownout Detection - A method and apparatus for real time clock brownout detection. A low power real time clock (RTC) operates continuously to keep time in a global positioning system (GPS) receiver while some receiver components are powered down. In various embodiments, a brownout detector circuit detects a loss of RTC clock cycles. If a loss of RTC clock cycles exceeds a predetermined threshold such that the RTC is not reliable for GPS navigation, an RTC status signal so indicates. | 12-31-2009 |
20090322604 | Method and Apparatus for Mitigating the Effects of Cross Correlation in a GPS Receiver - A positioning system receiver that mitigates cross correlation of received signals from positioning system satellite vehicles by generating the strong satellite vehicle signal and subtracting it from the received signal before correlation while eliminating the need for cross correlation signature without changing the C/A code. | 12-31-2009 |
20090258655 | System and method for integrating location information into an internet phone system - A system and a method for integrating the receipt and transmission of location information into VoIP phone systems. The system may include a location device that includes a SATPS receiver and an antenna together with one or more connectors that allow connection of the location device to other devices, such as a VoIP telephone and a router, that are connected to and made a part of a VoIP phone system. A method of operating such a system is also disclosed. | 10-15-2009 |
20090254275 | Systems and Methods for Monitoring Navigation State Errors - Systems and methods for monitoring navigation state errors are provided. In this regard, a representative system, among others, includes a receiver that is configured to receive GPS signals and calculate pseudorange (PR) residuals, the receiver including a navigation state error manager that is configured to: calculate a distance traveled by the receiver having the PR residuals, determine whether a navigation state has errors based on the calculated PR residuals and calculated distance, and responsive to determining that the navigation state has errors, send an error message indicating that the navigation state has errors. | 10-08-2009 |
20090237300 | SYSTEMS AND METHODS OF COMMUNICATION IN AN ASSISTED NAVIGATION SYSTEM - Provided herein are methods and systems for efficient communication between a server and a client in an assisted navigation system. In one or more embodiments, the client, e.g., a GPS receiver, receives a set of parameters for a satellite from the server via a wireless or wired connection. The set of parameters includes a force parameter, initial condition parameters and time correction coefficients for the satellite. The receiver uses the received parameters in a numerical integration to compute the position of the satellite at a desired time. The set of parameters needed for the integration is small compared to current methods which require sending more data to the client. Thus these parameters require less communication resources to transmit. To further reduce the amount of data that needs to be transmitted, reference parameters may be subtracted from the original parameters before transmission from the server. The receiver is able to reconstruct the original parameters from the received parameters and the identically computed reference parameters. The parameters may be further compressed using data compression techniques. | 09-24-2009 |
20090167447 | System and Method for Providing Temperature Correction in a Crystal Oscillator - A system and method for providing temperature compensation in a oscillator component (such as a crystal oscillator component) that includes a closely-located temperature sensing device. The crystal oscillator component in example systems and methods is exposed to a temperature profile during a calibration procedure. Temperature and frequency data are collected and applied to coefficient generating function according to a temperature compensation model to generate a set of coefficients that are used in the temperature compensation model in an application device. The generated coefficients are stored in a coefficient memory accessible to an application device during operation. | 07-02-2009 |
20090135060 | GPS System Utilizing Multiple Antennas - A GPS Mobile Unit is described. The GPS Mobile Unit may include at least two antennas, at least two GPS receivers, and a position solution module in signal communication with the at least two GPS receivers. | 05-28-2009 |
20090128407 | Systems and Methods for Detecting GPS Measurement Errors - Systems and methods for detecting global positioning system (GPS) measurement errors are provided. In this regard, a representative system, among others, includes a navigation device that is configured to receive GPS signals from signal sources, the navigation device being configured to calculate pseudoranges (PRs) and delta ranges (DRs) based on the received GPS signals, the navigation device including a consistency check algorithm that is configured to: determine mismatches between the respective calculated PRs and DRs, and indicate that an error exists in the respective calculated PRs and DRs based on their mismatch and mismatch accumulations. This algorithm can be independent of navigation state and is capable of detecting slow-changing errors. | 05-21-2009 |
20090119015 | Systems and Methods for Processing Navigational Solutions - Systems and methods for processing navigational solutions are provided. In this regard, a representative system includes a navigational computing device comprising a processor and memory that stores a navigational solution manager that is executed by the processor to provide a receiver position. The navigational solution manager is configured to collect navigational data from at least one satellite vehicle, compute initialization navigational measurements based on the collected navigational data, and compute the receiver position using the initialization navigation measurements. | 05-07-2009 |
20090115656 | Systems and Methods for Global Differential Positioning - Systems and methods for global differential positioning are provided. In this regard, a representative system, among others, may include a first receiver being configured to receive global correction data from a single source; and a computing device being configured to adjust positional estimates based on the received global correction data. A representative method, among others, for global differential positioning may include receiving satellite measurement information; receiving global correction data from a single source; generating location information based on the received satellite information; adjusting the location information based on the global correction data to produce adjusted location information; and delivering the adjusted location information. | 05-07-2009 |
20090109087 | Systems and Methods for Sharing an Oscillator Between Receivers - Systems and methods for sharing an oscillator between receivers are disclosed. A representative method (among others) of responding to a change in frequency of a voltage-controlled temperature-compensated oscillator (VCTCXO), includes: determining a new value for VCTCXO frequency; determining a time at which the new value will be applied to the VCTCXO; transmitting the time and the new value to a subsystem that uses a second receiver which shares the VCTCXO with a first receiver; and in the subsystem, updating channel context data to use the time of the change in frequency and the new value. | 04-30-2009 |
20090033553 | GPS-BASED POSITIONING SYSTEM FOR MOBILE GPS TERMINALS - The present invention discloses a GPS system that uses call-processor intelligence to determine the mode of operation of a GPS receiver located in a GPS terminal. The modes are selected based on the availability of network facilities, the GPS information that can be acquired, or user input requirements. | 02-05-2009 |
20080309553 | Systems and Methods for Mitigating Multipath Signals - Systems and methods for mitigating multipath signals in a receiver are provided. In this regard, a representative system, among others, includes a receiver comprising an antenna being configured to receive signals from a plurality of satellites, and a computing device being configured to: generate pseudorange measurements based on the received satellites signals, process the generated pseudorange measurements to reduce its pseudorange residuals based on statistical modeling in order to mitigate multipath errors, and compute navigation solutions based on the processed pseudorange measurements. A representative method, among others, for mitigating multipath signals in a receiver, comprises: receiving the pseudorange measurements; processing the received pseudorange measurements to reduce its pseudorange residuals based on statistical modeling in order to mitigate multipath errors; and computing navigation solutions based on the processed pseudorange measurements. | 12-18-2008 |
20080234933 | Systems and Methods for Detecting a Vehicle Static Condition - Systems and methods for detecting a vehicle static condition are provided. In this regard, a representative system includes a sensor operative to detect at least one of acceleration and angular rate of a vehicle. The sensor is further operative to generate a vehicle vibration profile based on the at least one of the detected acceleration and angular rate of the vehicle. The system further includes a computing device operative to receive the vehicle vibration profile from the sensor, the computing device being further operative to determine whether the vehicle is stationary or moving based on the vehicle vibration profile. A representative method for detecting a vehicle static condition includes detecting at least one of acceleration and angular grade of a vehicle; generating a vehicle vibration profile based on at least one of the detected acceleration and angular grade of the vehicle; receiving the vehicle vibration profile; and determining whether the vehicle is stationary or moving based on the vehicle vibration profile. | 09-25-2008 |
20080204316 | MEASUREMENT FAULT DETECTION - The present invention discloses a method and an apparatus for improving measurement fault detection in a sequential measurement processing estimator, and is particularly applied to Global Positioning Receivers. | 08-28-2008 |