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

Abstract: An apparatus for determining signal strength data within allocated GNSS frequency band(s) 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.

Abstract: A graphics-aided geodesic device is provided. The device includes an antenna for receiving position data from a plurality of satellites and a receiver coupled to the antenna. The device further includes orientation circuitry for obtaining orientation data. The orientation data represents an orientation of the apparatus with respect to a plane parallel with a horizon. The device further includes positioning circuitry for determining the position of the point of interest based at least on the position data and the orientation data.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: Prediction methods for navigation message symbols of satellite systems, such as GPS (Global Positioning System) and GLONASS (Global Orbiting Navigation System), that use information repetition in navigation data messages are disclosed. The methods enable one to eliminate the impact of symbol modulation for a received signal on the threshold performance of any navigation receiver, thereby permitting its operation in severe environments when the carrier-to-noise ratio C/N0 of “weak” satellite signals falls to levels below C/N0=20 dB*Hz.