The present disclosure relates generally to a portable Global Navigation Satellite System (GNSS). An exemplary surveying system comprises: a total station; a GNSS device; a coupling mechanism for coupling the GNSS device with the total station; wherein the system is configured to: determine, based on one or more outputs from the GNSS device, whether a set of GNSS signals is available; in accordance with a determination that the set of GNSS signals is available, determine a position of a point based on the set of GNSS signals; in accordance with a determination that the set of GNSS signals is not available, automatically determine a position of the point based on an angular measurement and a distance measurement with respect to the point obtained by the total station.
G01S 19/48 - Determining position by combining or switching between position solutions derived from the satellite radio beacon positioning system and position solutions derived from a further system
G01S 19/43 - Determining position using long or short baseline interferometry
G01S 19/39 - Determining a navigation solution using signals transmitted by a satellite radio beacon positioning system the satellite radio beacon positioning system transmitting time-stamped messages, e.g. GPS [Global Positioning System], GLONASS [Global Orbiting Navigation Satellite System] or GALILEO
G01C 11/02 - Picture-taking arrangements specially adapted for photogrammetry or photographic surveying, e.g. controlling overlapping of pictures
An exemplary method of calculating a position of a GNSS device (e.g., a GNSS rover device) comprises: at the GNSS device in an enhanced real-time kinematic (RTK) mode: receiving a first set of GNSS data corresponding to a first epoch; storing the first set of GNSS data in a buffer; receiving a second set of GNSS data corresponding to a second epoch that is after the first epoch; after receiving the second set of GNSS data, retrieving the first set of GNSS data from the buffer; and calculating the position of the GNSS device based on the retrieved first set of GNSS data and the second set of GNSS data.
G01S 19/04 - Cooperating elements; Interaction or communication between different cooperating elements or between cooperating elements and receivers providing carrier phase data
A method of calibrating a total station using a GNSS device includes physically coupling the total station with the GNSS device at a first location; determining the position of the total station at the first location based on position data received by the GNSS device; decoupling the total station from the GNSS device; moving the GNSS device to a second location while leaving the total station at the first location; determining the position of the GNSS device at the second location based on position data received by the GNSS device; adjusting the position of a camera on the total station to image the GNSS device while at the second location; determining axes of the camera based on the orientation of the camera and the determined positions at the first and second locations; and calibrating encoders of the total station based on the determined axes.
G01S 19/12 - Cooperating elements; Interaction or communication between different cooperating elements or between cooperating elements and receivers providing dedicated supplementary positioning signals wherein the cooperating elements are telecommunication base stations
G01S 19/23 - Testing, monitoring, correcting or calibrating of a receiver element
G01S 19/26 - Acquisition or tracking of signals transmitted by the system involving a sensor measurement for aiding acquisition or tracking
G01S 19/07 - Cooperating elements; Interaction or communication between different cooperating elements or between cooperating elements and receivers providing data for correcting measured positioning data, e.g. DGPS [differential GPS] or ionosphere corrections
An exemplary method of calculating a position of a GNSS device (e.g., a GNSS rover device) comprises: at the GNSS device in an enhanced real-time kinematic (RTK) mode: receiving a first set of GNSS data corresponding to a first epoch; storing the first set of GNSS data in a buffer; receiving a second set of GNSS data corresponding to a second epoch that is after the first epoch; after receiving the second set of GNSS data, retrieving the first set of GNSS data from the buffer; and calculating the position of the GNSS device based on the retrieved first set of GNSS data and the second set of GNSS data.
G01S 19/04 - Cooperating elements; Interaction or communication between different cooperating elements or between cooperating elements and receivers providing carrier phase data
A method of calibrating a total station having a laser based range finder is disclosed. The method includes the steps of positioning a first subsystem including the total station and a first RTK receiver at a first location and determining that location using RTK location information. A second subsystem having an optical target and a second RTK receiver is positioned at a first remote location and that location is determined by an RTK approach. The distance and azimuthal information between first and second subsystems is determined by the total station. The second subsystem is moved to a plurality of additional remote locations and the determinations are repeated. The results are used to calibrate the total station.
G01S 17/18 - Systems determining position data of a target for measuring distance only using transmission of interrupted, pulse-modulated waves wherein range gates are used
G01S 17/89 - Lidar systems, specially adapted for specific applications for mapping or imaging
A surveying system includes a first subsystem having a GNSS base station and an optical base station. The optical base station includes an optical sensor, a laser module, and one or more motors configured to reposition the optical sensor. The GNSS base station and the optical base station are configured to be coupleable in a first predefined configuration. The system further includes a second subsystem comprising a GNSS rover communicatively coupled to the GNSS base station and an optical rover comprising a visual pattern. The GNSS rover and the optical rover are configured to be coupleable in a second predefined configuration.
The present disclosure relates generally to a portable Global Navigation Satellite System (GNSS). An exemplary surveying system comprises: a total station; a GNSS device; a coupling mechanism for coupling the GNSS device with the total station; wherein the system is configured to: determine, based on one or more outputs from the GNSS device, whether a set of GNSS signals is available; in accordance with a determination that the set of GNSS signals is available, determine a position of a point based on the set of GNSS signals; in accordance with a determination that the set of GNSS signals is not available, automatically determine a position of the point based on an angular measurement and a distance measurement with respect to the point obtained by the total station.
G01S 19/48 - Determining position by combining or switching between position solutions derived from the satellite radio beacon positioning system and position solutions derived from a further system
G01S 19/43 - Determining position using long or short baseline interferometry
G01S 19/39 - Determining a navigation solution using signals transmitted by a satellite radio beacon positioning system the satellite radio beacon positioning system transmitting time-stamped messages, e.g. GPS [Global Positioning System], GLONASS [Global Orbiting Navigation Satellite System] or GALILEO
G01C 11/02 - Picture-taking arrangements specially adapted for photogrammetry or photographic surveying, e.g. controlling overlapping of pictures
8.
Method of calibrating a total station using a GNSS device
A method of calibrating a total station using a GNSS device includes physically coupling the total station with the GNSS device at a first location; determining the position of the total station at the first location based on position data received by the GNSS device; decoupling the total station from the GNSS device; moving the GNSS device to a second location while leaving the total station at the first location; determining the position of the GNSS device at the second location based on position data received by the GNSS device; adjusting the position of a camera on the total station to image the GNSS device while at the second location; determining axes of the camera based on the orientation of the camera and the determined positions at the first and second locations; and calibrating encoders of the total station based on the determined axes.
G01C 11/02 - Picture-taking arrangements specially adapted for photogrammetry or photographic surveying, e.g. controlling overlapping of pictures
G01S 19/26 - Acquisition or tracking of signals transmitted by the system involving a sensor measurement for aiding acquisition or tracking
G01S 19/07 - Cooperating elements; Interaction or communication between different cooperating elements or between cooperating elements and receivers providing data for correcting measured positioning data, e.g. DGPS [differential GPS] or ionosphere corrections
G01S 19/23 - Testing, monitoring, correcting or calibrating of a receiver element
G01S 19/12 - Cooperating elements; Interaction or communication between different cooperating elements or between cooperating elements and receivers providing dedicated supplementary positioning signals wherein the cooperating elements are telecommunication base stations
Systems and methods for performing spoofing detection and rejection including receiving, at a Global Navigation Satellite System (GNSS) device having an antenna, a set of signals, identifying a questionable signal in the set of signals, and in accordance with a determination that the set of signals includes a subset of valid GNSS satellite signals, where the subset satisfies a minimum number of valid GNSS satellite signals and does not include the questionable signal, calculating an approximate position of the GNSS device based on the subset of valid GNSS satellite signals.
A handheld GNSS device having a GNSS antenna, memory, and a display receives a first GNSS signal at the GNSS antenna and determines a first position of a point of interest based on the GNSS signal. The first position is stored in memory. A second GNSS signal is received at the GNSS antenna and a second position of the point of interest is determined based on the second GNSS signal. The second position is stored in memory. A third GNSS signal is received at the GNSS antenna and a third position of the point of interest is determined based on the third GNSS signal. The third position is stored in memory. A determination is made whether the first, second, and third positions meet a clustering criteria. In accordance with a determination that the first, second, and third positions meet the clustering criteria, a first cluster position is stored. The first cluster position is based on the first, second, and third positions. In accordance with a determination that the first and second positions meet the clustering criteria and the third position does not meet the clustering criteria, a second cluster position is stored. The second cluster position is based on the first and second and not the third position.
Embodiments of the present disclosure relate to a magnetic locator for a GNSS device. The magnetic locator includes a magnetic field sensor configured to detect a magnetic field adjacent the magnetic locator; a controller coupled to the magnetic field sensor and configured to receive from the magnetic field sensor measurement data based on the magnetic field and calculate sensor data based on the received measurement data; a communication interface coupled to the controller and adaptable to transmit sensor data received from the controller to the GNSS device; a connector adaptable to connect the magnetic locator to a GNSS antenna of the GNSS device; and a housing.
G01S 19/45 - Determining position by combining measurements of signals from the satellite radio beacon positioning system with a supplementary measurement
G01S 19/23 - Testing, monitoring, correcting or calibrating of a receiver element
A method of determining a position of a GNSS device includes receiving GNSS signals at the GNSS device from a plurality of GNSS satellites. The GNSS device generates GNSS raw data based on the GNSS signals. The GNSS raw data is stored on the GNSS device. The GNSS device receives first correction data and second correction data. The first correction data and the second correction data are generated from data from at least one reference station. Third correction data is determined based on the first correction data, the second correction data, and the GNSS raw data. Position data for the GNSS device is determined based on the third correction data and the GNSS raw data.
A GNSS device includes an antenna configured to receive a first plurality of GNSS signals from a first plurality of GNSS satellites and a second plurality of GNSS signals from a second plurality of GNSS satellites. The GNSS device also includes a communications interface configured to receive correction signals from a GNSS base unit. A processor of the GNSS device is coupled to the antenna and communications interface for processing data from the first plurality of GNSS signals and the second plurality of GNSS signals. Memory of the GNSS device includes executable instructions for several steps. A first algorithm is executed to determine first position data for the GNSS device based on the first plurality of GNSS signals and a correction signal received at the GNSS device from the GNSS base unit. The first position data is stored memory of the GNSS device. A second algorithm is executed to determine second position data for the GNSS device based on the second plurality of GNSS signals. In response to the second algorithm failing to determine the second position data, GNSS signal data is stored in memory of the GNSS device. The GNSS signal data is based on the second plurality of GNSS signals. The GNSS signal data are transmitted to an external device.
G01S 19/05 - Cooperating elements; Interaction or communication between different cooperating elements or between cooperating elements and receivers providing aiding data
G01S 19/25 - Acquisition or tracking of signals transmitted by the system involving aiding data received from a cooperating element, e.g. assisted GPS
G01S 19/09 - Cooperating elements; Interaction or communication between different cooperating elements or between cooperating elements and receivers providing processing capability normally carried out by the receiver
G01S 19/41 - Differential correction, e.g. DGPS [differential GPS]
A method for using a GNSS device to determine a position of an unknown point includes determining positions of a first point, a second point, and a third point using the GNSS device. A first image is captured of the first point using an image sensor, the image includes the unknown point and at least one of the second point or the third point. A second image is captured from the second point; the second image includes the unknown point and at least one of the second point or the third point. A third image is captured from the third point; the third image includes the unknown point and at least one of the second point or the first point. A position of the unknown point is calculated based on the first, second, and third images and the first, second, and third positions.
G01C 15/00 - Surveying instruments or accessories not provided for in groups
G01S 19/45 - Determining position by combining measurements of signals from the satellite radio beacon positioning system with a supplementary measurement
G01C 15/08 - Plumbing or registering staffs or markers over ground marks
G01C 11/02 - Picture-taking arrangements specially adapted for photogrammetry or photographic surveying, e.g. controlling overlapping of pictures
G01S 19/14 - Receivers specially adapted for specific applications
G01S 19/07 - Cooperating elements; Interaction or communication between different cooperating elements or between cooperating elements and receivers providing data for correcting measured positioning data, e.g. DGPS [differential GPS] or ionosphere corrections
G01S 19/48 - Determining position by combining or switching between position solutions derived from the satellite radio beacon positioning system and position solutions derived from a further system
G01S 19/26 - Acquisition or tracking of signals transmitted by the system involving a sensor measurement for aiding acquisition or tracking
G01S 19/41 - Differential correction, e.g. DGPS [differential GPS]
Documenting the two-dimensional tilt of a GNSS device includes focusing an image sensor on a location of a level having an appearance that indicates the two-dimensional tilt of the GNSS device. A first image of a scene is captured with the image sensor. The first image includes the level. A portion of the first image is displayed and includes the level on a display of the GNSS device. Position information for the GNSS device is also displayed on the display.
G01S 19/07 - Cooperating elements; Interaction or communication between different cooperating elements or between cooperating elements and receivers providing data for correcting measured positioning data, e.g. DGPS [differential GPS] or ionosphere corrections
G01C 11/02 - Picture-taking arrangements specially adapted for photogrammetry or photographic surveying, e.g. controlling overlapping of pictures
G01S 19/45 - Determining position by combining measurements of signals from the satellite radio beacon positioning system with a supplementary measurement
G01S 19/26 - Acquisition or tracking of signals transmitted by the system involving a sensor measurement for aiding acquisition or tracking
G01S 19/41 - Differential correction, e.g. DGPS [differential GPS]
G01S 19/48 - Determining position by combining or switching between position solutions derived from the satellite radio beacon positioning system and position solutions derived from a further system
Systems and methods for performing land surveying using real-time kinematic (RTK) engine verification are provided. In one example, a first set of positions of a GNSS receiver may be determined using each of a plurality of RTK engines. If a number of the plurality of RTK engines that produce a fixed solution is greater than or equal to a threshold value, a position of the GNSS receiver may be determined based on at least a portion of the first set of positions. The determined position may then be stored. This process may be repeated any number of times to produce a desired number of stored positions. In response to the number of stored positions being equal to a minimum value, a final position of the GNSS device may be determined based on the stored positions.
Systems and methods for synchronizing a global navigation satellite system (GNSS) receiver with a GNSS signal are provided. In one example, a GNSS receiver may include one or more sets of 20 GNSS channels that are each configured to integrate a received GNSS signal over a 20 millisecond accumulation window to output a navigation message bit. The accumulation windows of the 20 GNSS channels may be delayed relative to other windows of the 20 GNSS channels by 1 millisecond. The GNSS receiver may identify one of the 20 GNSS channels having the correct synchronization with the GNSS signal based on the navigation message bits output by the 20 GNSS channels. The identified GNSS channel having the correct synchronization with the GNSS signal may be used to determine a location of the GNSS receiver.
Systems and methods for performing automated localization are provided. In one example method, a plurality of coordinates representing positions of a plurality of locations may be received. The plurality of coordinates may be from two or more different coordinate systems. The numerical values of each of the plurality of coordinates may be evaluated to determine the coordinate system to which the coordinate belongs. The coordinates may be grouped into sets of coordinates based on their determined coordinate systems. Coordinates from one coordinate system may be paired with coordinates that represent the same locations from another coordinate system. A shape matching algorithm may be used to determine coordinates from different systems that represent the same locations. A localization process may then be used to convert the coordinates of the first coordinate system into coordinates of the second coordinate system based on the paired coordinates.
G01S 19/39 - Determining a navigation solution using signals transmitted by a satellite radio beacon positioning system the satellite radio beacon positioning system transmitting time-stamped messages, e.g. GPS [Global Positioning System], GLONASS [Global Orbiting Navigation Satellite System] or GALILEO
Systems and methods for surveying using a GNSS device are provided. In one example method, a GNSS device may be used to determine the location of points along a path and to add those points to a set of points representing the path. When adding each point, the device may determine if the point represents a new point or a previously measured point. If the point is a new point, the device may add the point to the set of points. If the point is a previously measured point, the device may display one or more previously measured points to allow the user to select which previously measured point corresponds to the point currently being measured. The user may select a previously measured point and a point may be added to the set of points using the location of the selected previously measured point.
Low-noise amplifier (LNA) filters and processes for filtering global navigation satellite system (GNSS) signals are disclosed. The LNA filters can be used to down-convert a received GNSS signal to a lower frequency, filter the GNSS signal at the lower frequency, and up-convert the GNSS signal to the original frequency of the GNSS signal. The down-converted frequency can be selected based on a temperature of the GNSS signal to compensate for shifts in the frequency response of the filter due to temperature changes.
A low-noise amplifier (LNA) filter for use with global navigation satellite system (GNSS) devices is disclosed. A first LNA stage, which is configured to connect to an antenna configured to receive GNSS signals, includes an LNA. A second LNA stage, which is connected to the output of the first LNA stage, has a surface acoustic wave (SAW) filter and an LNA. A third LNA stage, which is connected to the output of the second LNA stage, also has a SAW filter and an LNA.
A method for marking a point of interest in a live image on a navigation device is provided. A position of a navigation device is determined based on navigation signals received from satellites. An orientation of the device is determined based on data from an orientation sensor. A first live image is obtained from a first camera and displayed. A first marker is displayed in the first live image. The first marker indicates a first location of the point of interest in the first live image. A second live image is obtained and displayed. A second marker is displayed in the second live image. The second marker indicates a second location of the point of interest in the second live image. The first and second locations are based on the position of the device, the orientation of the device and the position of the point of interest.
A method for mitigating the effects of multipath errors in GNSS devices is provided. Signals from GNSS satellites are received. Image data from an image sensor is received. Orientation data from an orientation sensor is received. The orientation data describes the orientation of the image sensor. Obstruction data is determined based on the image data. The obstruction data includes an obstruction region that indicates the sky in that region is obstructed by a structure. Based on the orientation data, obstruction data, and GNSS satellite location data, the position of GNSS satellites with respect to the obstruction region is determined. The location of the GNSS device is determined based on signals from some of the GNSS satellites and the position of GNSS satellites with respect to the obstruction region.
The position of a global navigation satellite system (GNSS) surveying receiver is determined based on a plurality of RTK engines. A first RTK engine is implementing using a first set of parameters. A second RTK engine is implemented using a second set of parameter different than the first set. A plurality of GNSS signals are received from multiple satellites. At least one correction signal is received from at least one base receiver. A first position is determined from the first RTK engine based on the GNSS signals and the at least one correction signal. A second position is determined from the first RTK engine based on the GNSS signals and the at least one correction signal. A final position of the GNSS surveying receiver is determined based on the first position or the second position or a combination of both positions.
Dynamic inter-channel bias calibration of a navigational receiver is provided. A reference signal is propagated through front-end circuitry of the receiver. A delay caused by the propagation of the reference signal through the front-end circuitry is measured. The inter-channel bias of the navigational receiver is reduced using the measured delay associated with the front-end circuitry of the receiver.
An apparatus for determining signal strength data within at least one allocated GNSS frequency band is provided. The apparatus includes a GNSS antenna. The GNSS antenna receives signals within the allocated GNSS frequency band. The apparatus further includes receiving circuitry. The receiving circuitry is for demodulating the received signals. The apparatus further includes a processor and memory for storing instructions, executable by the processor. The instructions include instructions for generating signal strength data for the received signals within the GNSS allocated frequency based on the demodulated signals, and for determining a position for a point of interest based upon the demodulated signals. Included in the apparatus is a display screen for displaying a graphical representation of the signal strength data of at least a portion of the at least one GNSS allocated frequency band. The graphical representation identifies interference within at least the portion of the at least one GNSS allocated frequency band.
A handheld GNSS device includes a housing, handgrips integral to the housing for enabling a user to hold the device, and a display screen integral with the housing. The device has a GNSS antenna and a communication antenna, both integral with the housing. The GNSS antenna receives position data from GNSS satellites. The communication antenna receives positioning assistance data from a base station. The GNSS antenna has a first antenna pattern, and the communication antenna has a second antenna pattern. The first and second antenna patterns are substantially separated. Coupled to the GNSS antenna, within the housing, is at least one receiver. Further, the device includes, within the housing, orientation circuitry for generating orientation data, imaging circuitry for obtaining image data, and positioning circuitry for determining a position for the point of interest based on the position data, the positioning assistance data, the orientation data, and the image data.
G01S 19/40 - Correcting position, velocity or attitude
G01S 19/47 - Determining position by combining measurements of signals from the satellite radio beacon positioning system with a supplementary measurement the supplementary measurement being an inertial measurement, e.g. tightly coupled inertial
A method and apparatus for operating a vehicle under manual or automatic steering mode is disclosed herein. An estimation of an attraction domain of stability is calculated for the vehicle using the vehicle's current position and orientation information relative to a target trajectory. If an unstable estimation of the attraction domain is determined, then the vehicle is operated in manual mode under control of an operator.
A rover processor determines position of a rover based upon the interaction between multiple antennas located at the rover and multiple antennas located at a base. The rover antennas may include a rover master antenna having a phase center located at the centroid of the antennas patterns of at least two auxiliary rover antennas. The rover processor may determine the position of the rover master antenna based upon the relative positions of at least two rover antennas (e.g., the rover master antenna and at least one rover auxiliary antenna, or at least two rover auxiliary antennas) with respect to at least two antennas of a base transceiver.
A handheld GNSS device for determining position data for a point of interest is provided. The device includes a housing, handgrips integral to the housing for enabling a user to hold the device, and a display screen integral with the housing for displaying image data and orientation data to assist a user in positioning the device. The device further includes a GNSS antenna and at least one communication antenna, both integral with the housing. The GNSS antenna receives position data from a plurality of satellites. One or more communication antennas receive positioning assistance data related to the position data from a base station. The GNSS antenna has a first antenna pattern, and the at least one communication antenna has a second antenna pattern. The GNSS antenna and the communication antenna(s) are configured such that the first and second antenna patterns are substantially separated. Coupled to the GNSS antenna, within the housing, is at least one receiver. Further, the device includes, within the housing, orientation circuitry for generating orientation data of the housing based upon a position of the housing related to the horizon, imaging circuitry for obtaining image data concerning the point of interest for display on the display screen, and positioning circuitry, coupled to the at least one receiver, the imaging circuitry, and the orientation circuitry, for determining a position for the point of interest based on at least the position data, the positioning assistance data, the orientation data, and the image data.
G01S 19/14 - Receivers specially adapted for specific applications
G01S 19/40 - Correcting position, velocity or attitude
G01S 19/47 - Determining position by combining measurements of signals from the satellite radio beacon positioning system with a supplementary measurement the supplementary measurement being an inertial measurement, e.g. tightly coupled inertial
A computer-implemented method for generating at least one segment of an offset path for a vehicle based on at least one segment of a base path is provided. The at least one segment of the base path is represented by a stored set of data points. The computer-implemented method includes comparing the at least one segment of the base path to a curvature constraint to determine if the at least one segment of the base path violates the curvature constraint. The curvature constraint is based on a characteristic of the vehicle and a desired offset distance from the at least one segment of the base path. The characteristic reflects the vehicle's ability to traverse at least one segment of a path. The method further includes modifying the at least one segment of the base path to satisfy the curvature constraint, if the at least one segment of the base path violates the curvature constraint. At least one segment of an offset path for the vehicle to follow is generated based upon the desired offset distance from the modified at least one segment of the base path.
A graphics-aided geodesic device is provided. The device may include a display, camera, distance meter, GNSS (Global Navigation Satellite System, including GPS, GLONASS, and Galileo) receiver and antenna, and horizon sensors. Data from the camera and horizon sensors may be displayed to assist the user in positioning the device over a point of interest. In one example, the distance meter may be used to determine the position of the point of interest. In another example, images of the point of interest taken from multiple locations may be used to determine the position of the point of interest.
An apparatus and method for providing image contrast enhancement is disclosed. A mobile object is equipped with a laser source, polarization filter, and imaging apparatus. The reflection of the laser source output passes through the filter and is received by the imaging apparatus. If the output of the laser source impinges a metallic marker plate located at a pre-determined location, the filter decreases the intensity level of image components not associated with the reflection of the laser source output. The imaging apparatus uses such filtered image components to determine the position and/or orientation of the mobile object.
A portable DGPS navigation apparatus is provided. The apparatus includes a receiver assembly and a DGPS antenna assembly. The receiver assembly includes a GNSS antenna, a GNSS receiver, and a DGPS modem. The DGPS antenna assembly includes a DGPS antenna; a top connector for coupling the DGPS antenna assembly to the receiver assembly such that the receiver assembly and DGPS antenna assembly are aligned with a geodetic pole, and a bottom connecter.
Dynamic inter-channel bias calibration of a navigational receiver is provided. A reference signal is propagated through front end circuitry of the receiver. A delay caused by the propagation of the reference signal through the front end circuitry is measured. The inter-channel bias of the navigational receiver is reduced using the measured delay associated with the front end circuitry of the receiver.
A portable navigation apparatus is provided. The apparatus includes a multi-antenna assembly configured for including an expanded configuration and a collapsed configuration. The antenna assembly includes a master antenna, and at least two auxiliary antennas. The at least two auxiliary antennas are radially distributed about the master antenna. Furthermore, the master antenna and auxiliary antennas are substantially coplanar when the antenna assembly is in the expanded configuration.
A rover processor determines position of a rover based upon the interaction between multiple antennas located at the rover and multiple antennas located at a base. The rover antennas may include a rover master antenna having a phase center located at the centroid of the antennas patterns of at least two auxiliary rover antennas. The rover processor may determine the position of the rover master antenna based upon the relative positions of at least two rover antennas (e.g., the rover master antenna and at least one rover auxiliary antenna, or at least two rover auxiliary antennas) with respect to at least two antennas of a base transceiver.
2-smooth, and the curve does not exceed the steering capability of the vehicle. The segments may comprise cubic B-spline segments. If the identified points are not substantially equidistant, then an auxiliary curve approximating the trajectory is generated, and a set of substantially equidistant points on the auxiliary curve is selected as the identified points.
patents
