Unconventional range navigation system with efficient update process
Granted: July 31, 2001
Patent Number:
6268823
Method and system for determining a position of a platform using a set of range measurements between the platform and a set of known positions that avoids the frequent recalculation of square-roots in range predictions. The platform state estimate is updated by substituting the difference between the square of the range measurement and the square of the distance from the assumed position of the platform to the known position to which the range measurement corresponds scaled by the…
Code group delay calibration using error free real time calibration signal
Granted: July 24, 2001
Patent Number:
6266007
The present invention discloses the apparatus and the method for calibrating a Narrow Band Receiver in real time for code group delay errors in the signals transmitted by a Narrow Band Transmitter. The apparatus includes a Calibration circuit used to generate a calibration signal that is substantially free from code delay errors, and that is substantially similar to the signal emanating from the Narrow band Transmitter. The calibration signal can be used by the Narrow Band receiver to…
Position based personal digital assistant
Granted: July 24, 2001
Patent Number:
6266612
A task description is stored in a database accessible by a mobile computer system. The mobile computer system receives positioning information corresponding to its geographic location and indexes the database based on the positioning information when the information indicates that the mobile computer system is in a geographic location that facilitates completion of a task associated with the task description. The database may be resident in the mobile computer system or accessible in…
GPS positioning utilizing laser based reflectors augmentation
Granted: July 10, 2001
Patent Number:
6259403
The mobile unit equipped with the satellite positioning system augmented by the laser positioning system is disclosed. The usage of the satellite positioning system allows the user to determine the coordinate of the laser reflectors prior to the range measurements. The range measurements are performed by the navigational computer using the laser scanning and rotating beam to obtain the range data between the mobile unit and a plurality of laser reflectors, and using the satellite…
Antenna housing
Granted: June 26, 2001
Patent Number:
D444144
Method and apparatus for processing multipath reflection effects in timing systems
Granted: June 26, 2001
Patent Number:
6252546
A method and apparatus for processing multipath reflection effects in timing systems is disclosed in which a determination is made of whether a received signal is a reflected signal. A detector provides from an input signal a pair of signals representative of whether the input signal contained right-hand circularly polarized and left-hand circularly polarized components. The representative signals are separately processed in synchronized logic circuits to determine relative power levels.…
Multipath compensation for pseudorange signals
Granted: June 26, 2001
Patent Number:
6252863
Method and apparatus for synchronizing to a reference signal the timing of a received composite, code phase SATPS signal, such as a GPS or GLONASS signal, that consists of a preferred, interference-free signal distorted by at least one interfering signal, to determine an undistorted timing point, such as the preferred signal time of arrival. A first autocorrelation function ACI(&tgr;) is generated between the preferred, interference-free signal and a reference signal that replicates the…
Method and apparatus for calibrating a tool positioning mechanism on a mobile machine
Granted: June 26, 2001
Patent Number:
6253160
A method and apparatus for calibrating sensors of a tool positioning mechanism on a mobile machine are provided. The mobile machine includes a tool, a tool positioning mechanism having a plurality of sensors for providing signals indicative of the physical configuration of the mechanism, a satellite positioning system, and a plurality of positioning system antennas. One of the antennas is detachably mounted on the tool while an other antenna is mounted to a location on the machine other…
GPS true course guidance correction system for correcting antenna offset error
Granted: June 5, 2001
Patent Number:
6243649
A method for correcting yaw in a DGPS (global positioning system) based guidance system mounted on a vehicle. The method corrects for a yaw induced heading/cross track error due to a DGPS antenna being mounted a significant distance from the point of operation (e.g., the vehicle operator's location, the center of the vehicle, etc.). The method determines a ground track of a vehicle using a DGPS system and a coupled antenna mounted on the vehicle. A heading of the vehicle is also…
Tilt prediction for total station
Granted: June 5, 2001
Patent Number:
6243658
A tilt predictor incorporated into a total station to predict the degree of tilt of the rotational alidade portion of a total station corresponding to the rotational orientation of the rotational alidade portion. In one embodiment, the present invention defines the plane of rotation for the rotational alidade portion with the rotational alidade portion disposed in a first rotational orientation. The rotational alidade portion is then rotated to the desired rotational orientation. This…
Antenna housing
Granted: May 29, 2001
Patent Number:
D442947
Integrated split spectrum positioning system receiver
Granted: May 29, 2001
Patent Number:
6239743
A receiver for tracking sources of position system signals transmitted as split spectrum signals is disclosed. The receiver provides a digital tracker to track a portion of the split spectrum signal. Each digital tracker may have an independent tracking loop solely for tracking a respective portion of the split spectrum signal. Such an arrangement provides anti-jamming benefits. Alternatively, the tracking loops may be dependent by providing information ascertained by one digital tracker…
Bootstrapped location determination
Granted: May 29, 2001
Patent Number:
6239721
A system for determining the location of a moving signal-receiving station, when the primary location determination (LD) signals become unavailable because the antenna is adjacent to or within a signal-interfering structure, such as an urban canyon, a natural canyon, a forest or the like. Before the primary LD signals become unavailable, secondary LD signals are received at spaced apart locations and used to estimate the secondary LD signal source locations (preferably fixed). After the…
Fast recovery of lock point information for GPS RTK receiver
Granted: May 22, 2001
Patent Number:
6236355
Methods and systems for resolving the lock point ambiguity for the GPS receiver are disclosed. The method involves generation of the absolute lock point data bit by the reference station receiver, transmission of the absolute data bit to the rover receiver, and comparison between the raw lock point data with the absolute lock point data bit in the rover receiver. The system employs the reference station receiver, the rover receiver, and the communication link.
Global positioning system antenna housing
Granted: May 15, 2001
Patent Number:
D442168
Vehicle use control
Granted: May 15, 2001
Patent Number:
6232874
A system for restricting use of a vehicle by a selected vehicle operator to permitted time intervals and permitted vehicle travel corridors. If a driver is seated behind the driver's wheel, the system requires that the driver provide one or more samples of an ident indicium, such as a fingerprint, facial scan, retinal scan, voice sample or blood sample analysis, to identify the driver, or of a personal identification indicium contained on a token or card, or of personal information…
Predictive model for automated vehicle recommendation system
Granted: May 15, 2001
Patent Number:
6233517
A system and method for determining which of a plurality of vehicles is able to respond most quickly to an event. In one embodiment, the present invention divides a geographic region into a plurality of geographic cells. The present automatic vehicle recommendation system then calculates a response time for each of the plurality of vehicles to travel from each of the geographic cells to every other of the geographic cells. The position of each of the plurality of vehicles is monitored by…
Near-real time DGPS network and server system
Granted: May 8, 2001
Patent Number:
6229478
A method and system for rapidly initializing a rover unit in a networked system. In one embodiment, the present invention acquires rover unit initialization data at a reference station. In one embodiment, the rover unit initialization data is selected from the group consisting of: ephemeris data, almanac data, satellite health data, ionospheric data, UTC and GPS time and approximate rover position information. In the present embodiment, the present invention then communicatively couples…
Accurate vehicle navigation
Granted: May 8, 2001
Patent Number:
6230097
Method and system for accurate vehicle navigation and tracking within a selected lane on a roadway or a waterway. A location determination (LD) receiver, carried on the vehicle, receives LD signals from satellite-based LD signal sources, receives LD signal correction information from one or more other wide area LD correction sources, estimates a corrected vehicle location (good to within 10-50 cm) and velocity (optional) relative to one or more lane boundaries that define the selected…
Vehicle use control
Granted: May 1, 2001
Patent Number:
6225890
A system for restricting use of a vehicle by a selected vehicle operator to permitted time intervals and permitted vehicle travel corridors. If a driver is seated behind the driver's wheel, the system requires that the driver provide one or more samples of an ident indicium, such as a fingerprint, facial scan, retinal scan, voice sample or blood sample analysis, to identify the driver, or of a personal identification indicium contained on a token or card, or of personal information…
