| Patent application number | Description | Published |
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| 20100054115 | System and Method for Sidelobe Suppression in Communications Systems - A system and method for sidelobe suppression in OFDM communications systems is provided. A method for transmitting an information symbol having a plurality of information sub-carriers and a plurality of active interference cancellation (AIC) sub-carriers includes generating AIC sub-carrier data based on the information to be transmitted, populating the plurality of information sub-carriers with the information, populating the plurality of AIC sub-carriers with the AIC sub-carrier data, applying baseband processing to the information symbol, thereby producing a processed symbol, and transmitting the processed symbol. | 03-04-2010 |
| 20100073227 | Detecting Lack of Movement to Aid GNSS Receivers - Embodiments of the invention provide a method of detecting movement to aid GNSS receivers. By detecting when the user is stationary, the Doppler frequency estimation can be corrected or the SNR can be boosted more both of which lead to improved performance. The embodiments allow a GNSS receiver to process signals in when the signal level would otherwise be too low—for example indoors. The embodiments can improve performance when one or more satellites are temporarily blocked but one or more satellites are still being tracked. | 03-25-2010 |
| 20100079334 | LOW-COMPLEXITY TIGHTLY-COUPLED INTEGRATION FILTER FOR SENSOR-ASSISTED GNSS RECEIVER - Embodiments of the invention provide a blending filter based on extended Kalman filter (EKF), which optimally integrates the IMU navigation data with all other satellite measurements tightly-coupled integration filter. This blending filter can be easily implemented with minor modification to the position engine of stand-alone GNSS receiver. Provided is a low-complexity tightly-coupled integration filter for sensor-assisted global navigation satellite system (GNSS) receiver. The inertial measurement unit (IMU) contains inertial sensors such as accelerometer, magnetometer, and/or gyroscopes Embodiments also include method for pedestrian dead reckoning (PDR) data conversion for ease of GNSS/PDR integration. The PDR position data is converted to user velocity measured at the time instances where GNSS position/velocity estimates are available. | 04-01-2010 |
| 20100097268 | TIGHTLY-COUPLED GNSS/IMU INTEGRATION FILTER HAVING CALIBRATION FEATURES - Embodiments of the invention provide a blending filter based on extended Kalman filter (EKF), which optimally integrates the IMU navigation data with all other satellite measurements (tightly-coupled integration filter). Two more states in the EKF for estimating/compensating the speed bias and the heading bias in the INS measurement are added. The integration filter has no feedback loop for INS calibration, and can estimate/compensate the navigation error in the INS measurement within the integration filter. | 04-22-2010 |
| 20100103033 | LOOSELY-COUPLED INTEGRATION OF GLOBAL NAVIGATION SATELLITE SYSTEM AND INERTIAL NAVIGATION SYSTEM - Techniques for loosely coupling a Global Navigation Satellite System (“GNSS”) and an Inertial Navigation System (“INS”) integration are disclosed herein. A system includes a GNSS receiver, an INS, and an integration filter coupled to the GNSS receiver and the INS. The GNSS receiver is configured to provide GNSS navigation information comprising GNSS receiver position and/or velocity estimates. The INS is configured to provide INS navigation information based on an inertial sensor output. The integration filter is configured to provide blended position information comprising a blended position estimate and/or a blended velocity estimate by combining the GNSS navigation information and the INS navigation information, and to estimate and compensate at least one of a speed bias and a heading bias of the INS navigation information. | 04-29-2010 |
| 20100109945 | LOOSELY-COUPLED INTEGRATION OF GLOBAL NAVIGATION SATELLITE SYSTEM AND INERTIAL NAVIGATION SYSTEM: SPEED SCALE-FACTOR AND HEADING BIAS CALIBRATION - Techniques for loosely coupling a Global Navigation Satellite System (“GNSS”) and an Inertial Navigation System (“INS”) integration are disclosed herein. A system includes a GNSS receiver, an INS, and an integration filter coupled to the GNSS receiver and the INS. The GNSS receiver is configured to provide GNSS navigation information comprising GNSS receiver position and/or velocity estimates. The INS is configured to provide INS navigation information based on an inertial sensor output. The integration filter is configured to provide blended position information comprising a blended position estimate and/or a blended velocity estimate by combining the GNSS navigation information and the INS navigation information, and to estimate and compensate at least one of a speed scale-factor and a heading bias of the INS navigation information. | 05-06-2010 |
| 20100109950 | TIGHTLY-COUPLED GNSS/IMU INTEGRATION FILTER HAVING SPEED SCALE-FACTOR AND HEADING BIAS CALIBRATION - Embodiments of the invention provide a tightly-coupled integration filter for inertial sensor-assisted GNSS (global navigation satellite system) receiver. The inertial measurement unit (IMU) contains inertial sensors such as accelerometer, magnetometer, and/or gyroscopes. Embodiments include blending filter based on extended Kalman filter (EKF), which optimally integrates the IMU navigation data with all other satellite measurements (tightly-coupled integration filter). The proposed blending filter includes two states for estimating/compensating the speed scale-factor and the heading bias in the INS measurement. | 05-06-2010 |
| 20110316738 | Adjusting a Bandwidth of GNSS Receivers - Embodiments of the invention provide a method of adjusting a bandwidth of receivers. A plurality of outputs from a correlator engine are combined. User dynamics are sensed. Bandwidth of one or more receivers are adjusted. By detecting when the user is stationary, the Doppler frequency estimation can be corrected or the SNR can be boosted more both of which lead to improved performance. The embodiments allow a receiver to process signals in when the signal level would otherwise be too low—for example indoors. The embodiments can improve performance when one or more satellites are temporarily blocked but one or more satellites are still being tracked. | 12-29-2011 |
| 20110316740 | Reacquiring Satellite Signals Quickly - Embodiments of the invention provide a method of reacquiring satellite signals quickly. A pseudorange of at least one satellite is estimated. A user's position is also estimated. Then a signal from at one or more satellites may be received. By detecting when the user is stationary, the Doppler frequency estimation can be corrected or the SNR can be boosted more both of which lead to improved performance. The embodiments allow a GNSS receiver to process signals in when the signal level would otherwise be too low—for example indoors. The embodiments can improve performance when one or more satellites are temporarily blocked but one or more satellites are still being tracked. | 12-29-2011 |
