The Boeing Company

Hughes Electronics Corporation

Rongsheng Li

Yeong-Wei Andy Wu

David D Needelman

Richard A Fowell

Tung-Ching Tsao

Chang Jin Yoo

Yong Liu

Yeong-Wei A Wu

Garry Didinsky

Douglas H Hein

Peter C Lai

Hanching Grant Wang

Arunkumar Pursayya Nayak

Kamran Ghassemi

H Grant Wang

Cody L Gruebele

Jeffrey A Kurland

William L Burkett, Jr

Timothy Allen Murphy

Ketao Liu

Amir Leon Liaghati

Justin David Kearns

Naveed Moayyed Hussain

Brian Christopher Grubel

Danny M Kim

Richard Yining Chiang

Alireza Shapoury

Bruce N Eyerly

Matthew J Pelliccione

Clifford W Kelley

Christopher L Davis

David S Uetrecht

Grant Wang

Richard T Cervisi

David L Augenstein

Jack S Hagelin

Umesh S Ketkar

Greg L Sheffield

Christopher L Rice

Jonathan French

Tim A Murphy

Harold A Klotz, Jr

Shanshin Chen

Bruce M Pope

Hangching Grant Wang

Salma I Saeed

Paul J Haug

Alec M Dawson

James H Green

Michael A Rizzo

James H Kober

Travis M Autry

Andrey Tolstov

Kenneth Cecil Clark

James P Alstad

Lawrence E Pado

Kayode T Ariwodola

Jeff R Bennett

Johathan A Tekawy

A method includes receiving an output radio frequency (RF) signal. The method includes generating a digitized output RF signal representing the output RF signal. The method includes transmitting an output RF waveform associated with the output RF signal. The method includes receiving a return RF waveform based on transmission of the output RF waveform. The method includes generating a digitized return RF signal representing a return RF signal associated with the return RF waveform. The method includes serializing the digitized output RF signal and the digitized return RF signal to generate a serialized baseband signal. The method includes communicating a bit stream based on the serialized baseband signal to an RF unit. The RF unit is configured to generate an altitude measurement, a ground speed measurement, or both for a vehicle based on the serialized baseband signal.

Combined radio altimeter and doppler radar with surface-mountable antenna array

A personal navigation device comprising a body, a star tracker, an inclinometer, a clock, a GNSS receiver, and first and second position calculation modules. The first position calculation module is configured to calculate latitude and longitude of the body based on respective outputs from the star tracker, inclinometer, and clock. The second position calculation module is configured to calculate latitude and longitude of the body based on satellite signals received by the GNSS receiver. In one implementation, the star tracker includes a short-wave infrared camera and the inclinometer includes three accelerometers having non-coplanar axes. The personal navigation device may further include a display device, a display engine, and a user interface configured to enable selection of a particular method of calculating latitude and longitude depending on whether GNSS is available or not.

Personal navigation device operable in GNSS-denied environment

Methods and apparatus to reduce communications for position, navigation and timing (PNT) determinations are disclosed. A disclosed example apparatus to enable PNT determination for a mobile station includes at least one memory, machine readable instructions, and processor circuitry to at least one of instantiate or execute the machine readable instructions to identify features of signals of opportunity (SOOP) measured at a reference station, generate a model based on the identified features of the SOOP in conjunction with a position and a timing of the reference station, and provide at least one of the model or parameters associated with the model to the mobile station for the PNT determination.

Methods and apparatus to reduce communications for position, navigation and timing determinations

Sensor data fusion systems that provide noise reduction and fault protection. The sensor data fusion system fuses data acquired by respective accelerometers having different attributes. For example, one accelerometer has low noise and high bias, while another accelerometer has high noise and low bias when measuring specific force. The high-noise, low-bias accelerometer may be a gravimeter. Gravimeters and traditional accelerometers measure the same physical variable, i.e., specific force. By combining an expensive gravimeter and low-cost accelerometers, a synthetic sensor having both low noise and low bias may be achieved. Such synthetic sensors may be utilized in a gravity anomaly-referenced navigation system to achieve improved navigation performance.

Sensor data fusion system with noise reduction and fault protection

A navigation, take-off, and landing support system (NTLS) that facilitates vertical landing at a landing area by an aerial vehicle comprises a plurality of pseudolites distributed proximate the landing area. Each pseudolite is configured to transmit a radio frequency (RF) signal that facilitates determining, by the aerial vehicle, its position and velocity relative to the pseudolite and whether the pseudolite is operating within a nominal operating range. A monitoring receiver is positioned proximate the landing area and is configured to receive RF signals from the pseudolites. A control system is in communication with the pseudolites and the monitoring receiver. The control system is configured to determine, based on the RF signals received from the monitoring receiver, whether the pseudolites are operating within a nominal operating range and to indicate to each of the pseudolites whether the pseudolite is operating within a nominal operating range.

System and method that facilitates precision landing of an aerial vehicle

Systems and methods for inertial navigation aided by signals of opportunity (SOOP). One system includes a network operations center (NOC), a reference station, and mobile user equipment. Another system includes a NOC and user equipment without a reference station. In the latter system, the NOC comprises an antenna, a NOC receiver that generates SOOP data derived from SOOP, a computer system that generates SOOP source location/ephemeris data and inter-source clock bias data based on SOOP data generated by the NOC receiver, and a communication device to broadcast the data. The user equipment comprises an antenna, a navigation receiver that generates SOOP data derived from SOOP detected by the antenna of the user equipment, and a navigation computer system that calculates a navigation solution, including a SOOP-derived estimated position of the user equipment, based on SOOP source location/ephemeris data and inter-source clock bias data broadcasted by the NOC and SOOP data generated by the navigation receiver.

Position, navigation and timing system architecture based on signals of opportunity

A system, apparatus, and method for determining a velocity. A voltage is detected for a planar sensor array while the planar sensor array is moving though a magnetic field, wherein the planar sensor array comprises conductive channels formed in a substrate, wherein the conductive channels are connected in series, and wherein the voltage is generated by the planar sensor array in response to a movement of the planar sensor array through the magnetic field and wherein the voltage is proportional to a velocity of the planar sensor array moving through the magnetic field. The velocity of the planar sensor array is determined using the voltage detected for the conductive channels.

Lorentz force velocity sensor system

A terrain referenced navigation system for a vehicle is disclosed and includes an inertial measurement unit and one or more generic terrain sensors configured to collect terrain-dependent data. The terrain referenced navigation system includes one or more processors in electronic communication with the generic terrain sensors and the inertial measurement unit, and a memory coupled to the processors. The memory stores data into one or more databases and program code that, when executed by the processors, causes the terrain referenced navigation system to determine a predicted terrain value based on a terrain value, where the terrain value is retrieved from one or more sensor specific terrain databases. The pre-Kalman filter processing values are sent to a Kalman filter. The Kalman filter determines navigation corrections and sensor corrections based on the pre-Kalman filter processing values.

Terrain referenced navigation system with generic terrain sensors for correcting an inertial navigation solution

An estimator that is part of a communication network including a plurality of nodes is disclosed. A centralized portion of the estimator includes one or more processors in wireless communication with the plurality of nodes that are part of the communication network, where the communication network includes one or more pairs of collaborating nodes, and a memory coupled to the one or more processors, the memory storing data into a database and program code that, when executed by the one or more processors, causes the centralized portion of the estimator to determine a local update and a collaborative update. The collaborative update is applied to the respective estimated local state vector for both nodes of the pair of collaborating nodes.

Estimator for determining updates to an estimated local state vector

A celestial navigation system and method for determining a position of a vehicle. The system includes a star-tracker, a beam director, an inertial measurement unit, and a control module. The star-tracker has a field of view for capturing light. The beam director is configured to change a direction of the light captured in the field of view of the star-tracker. The inertial measurement unit has a plurality of sensors for measuring an acceleration and a rotation rate of the vehicle. The control module executes instructions to correct the attitude, the velocity and the position of the vehicle using the determined magnitude and position of the space objects. The control module also executes instructions to generate corrections to the IMU error parameters, the beam director and star-tracker alignment errors, and RSO ephemeris errors to achieve optimal performance.

Celestial navigation system and method

A communication network having a plurality of nodes is disclosed. An individual node of the communication network includes a measurement device configured to collect local measurements, an antenna configured to wirelessly connect the individual node to a collaborating node that is part of the communication network, one or more processors in electronic communication with the measurement device and the antenna, a memory coupled to the one or more processors, the memory storing data into a database and program code that, when executed by the one or more processors, causes the individual node to estimate, based on the local measurements, an estimated local state vector for the individual node. The individual node determines a collaborative update based on an estimated collaborative measurement and a collaborative residual, where the collaborative update is applied to the estimated local state vector for the individual node.

Systems and methods for providing improved navigation performance in which camera images are matched (using correlation) against reference images available from a geolocation-tagged database. An image-based navigation system partitions the camera image (corresponding to the area within the field-of-view of the camera) into a plurality of camera sub-images (corresponding to regions in that area), and then further partitions each camera sub-image into a multiplicity of tiles (corresponding to sub-regions within a region). The partitioning into camera sub-images seeks geometric diversity in the landscape. Each tile is checked for quality assurance, including feature richness, before correlation is attempted. The correlation results are further quality-checked/controlled before the results are used by the Kalman filter to generate corrections for use by the inertial navigation system. Respective lines-of-sight to multiple regions are measured using multiple tiles in each region to provide better observability and better performance.

Image-based navigation using quality-assured line-of-sight measurements

Methods and apparatus to monitor GPS/GNSS atomic clocks are disclosed. An example method includes establishing a measured difference between an atomic frequency standard (AFS) and a monitoring device. The method also includes modeling an estimated difference model between the AFS and the monitoring device, and computing a residual signal based on the measured difference and the estimated difference model. In addition, the method includes analyzing, by a first detector, the residual signal at multiple thresholds, each of the thresholds having a corresponding persistency defining the number of times a threshold is exceeded before one or more of a phase jump, a rate jump, or an acceleration error is indicated. Furthermore, the method includes analyzing, by a second detector, a parameter of the estimated difference model at multiple thresholds, each of the thresholds having a corresponding persistency defining the number of times a drift threshold is exceeded before a drift is indicated.

Multi-level/multi-threshold/multi-persistency GPS/GNSS atomic clock monitoring

Methods, systems, and computer-readable media are described herein for using a modified Kalman filter to generate attitude error corrections. Attitude measurements are received from primary and secondary attitude sensors of a satellite or other spacecraft. Attitude error correction values for the attitude measurements from the primary attitude sensors are calculated based on the attitude measurements from the secondary attitude sensors using expanded equations derived for a subset of a plurality of block sub-matrices partitioned from the matrices of a Kalman filter, with the remaining of the plurality of block sub-matrices being pre-calculated and programmed into a flight computer of the spacecraft. The propagation of covariance is accomplished via a single step execution of the method irrespective of the secondary attitude sensor measurement period.

Modified Kalman filter for generation of attitude error corrections

A system for navigation and tracking may include an inertial navigation system adapted to generate a replica GNSS signal and a global navigation satellite system. The global navigation satellite system may include a module to digitize a GNSS signal received from a constellation of global navigation satellites. A correlator receives the digitized GNSS signal and the replica GNSS signal. The correlator correlates the digitized GNSS signal to the replica GNSS signal to generate a correlated GNSS signal. A coherent integration module coherently integrates the correlated GNSS signal to generate an integrated signal having a predetermined rate. A filter receives the integrated signal and generates a data signal for navigation and tracking. An output device may present the navigation and tracking information based on the data signal, or the navigation and tracking information may be used to provide guidance for a vehicle or may be used to track a target.

Integrated global navigation satellite system and inertial navigation system for navigation and tracking

Growing community of inventors

Hacienda Heights, CA, United States of America

Rongsheng Li