Method and apparatus for automatically aiming an antenna to a distant location
Granted: January 18, 2000
Patent Number:
6016120
An antenna aiming method and apparatus for automatically pointing an antenna to a selected distant location. The antenna aiming apparatus includes a database for storing data for distant locations, an electronic compass for determining a reference azimuth for the local antenna, and a global positioning system (GPS) receiver for determining a local location. A processor computes a pointing direction having an azimuth and an elevation from the local location to the distant location and…
Rich character set entry from a small numeric keypad
Granted: January 18, 2000
Patent Number:
6016142
A processor is connected to a display screen to generate a screen display of individual characters in groups together with the selector indication. Such characters typically belong in a language set, e.g., English, Japanese, Greek, etc. The processor receives from the numeric keypad a user selection of a number "1-9" that is associated with a particular one of the individual characters in a group highlighted by the selector indication. An index-and-fetch mechanism, typically implemented…
Real time integration of a geoid model into surveying activities
Granted: January 18, 2000
Patent Number:
6016118
Method and apparatus for enhancing the accuracy of the elevation coordinate in a survey that uses GPS survey measurements to determine location coordinates for a plurality of survey locations. An optimal locally-best-fitting plane is combined with a geoid model that represents a local region of the Earth, in order to decrease the inaccuracy associated with an elevation coordinate in the survey to a fraction of a decimeter.
Post-processing of inverse DGPS corrections
Granted: January 11, 2000
Patent Number:
6014101
A method for enhancing the accuracy of location coordinates and/or clock bias computed for a mobile user station that is part of a Satellite Positioning System (SATPS), such as GPS or GLONASS. A data processing station is provided with pseudorange corrections PRC(t;j;ref) for an SATPS reference station for each of M SATPS satellites (j=1, . . . , M; M.gtoreq.3) and with uncorrected location fix coordinates x'(t.sub.f), y'(t.sub.f)', z'(t.sub.f)' and/or b'(t.sub.f) for the mobile station…
Offset-antenna total station
Granted: January 11, 2000
Patent Number:
6014109
The present invention provides a method and apparatus for expediently determining the azimuthal orientation of a total station. In one embodiment, the present invention is comprised of a total station having a vertical axis. The total station also includes a rotational alidade portion adapted to rotate about the vertical axis, and an electronic distance measuring portion. The present invention also includes a satellite-based position determining system antenna coupled to the total…
Antenna with stepped ground plane
Granted: January 11, 2000
Patent Number:
6014114
An antenna structure has a radiating element and a ground plane. The ground plane has a central region relatively closely spaced apart from the radiating element and a peripheral region extending away from the central region. The peripheral region comprises at least one conductive layer that extends radially beyond the radiating element and provides a sheet resistivity higher than that of the radiating element. Though physically small, the ground plane simulates an infinite ground plane,…
Integrated antenna system
Granted: January 4, 2000
Patent Number:
6011524
Disclosed herein is a low profile quadrifilar helix antenna system having the non-fed ends of the helix conductor arms shorted to a first ground plane, the ground plane mounted below the helix. The first ground plane is mounted perpendicularly to the central axis of the helix and extends radially outward therefrom to form an effective electromagnetic shield between the helix and adjacent ground planes. The extension of the first ground plane combined with the shorted non-fed ends of the…
Vehicle position reporting in user defined uni-dimensional coordinate system
Granted: January 4, 2000
Patent Number:
6012013
The method and the apparatus for the outputting in a uni-dimensional coordinate system the position coordinates and speed determined by the position and speed determining system (PSDS) are disclosed. The PSDS can include the SATPS receiver, the inertial positioning system, or the combination of both. The digital database of the geographic area is introduced by the user in the arbitrary coordinate system and is translated into the preferred coordinate system in order to define the…
Optimum utilization of pseudorange and range rate corrections by SATPS receiver
Granted: December 28, 1999
Patent Number:
6009551
The partial decoding algorithm for decoding the partially damaged differential satellite positioning system (SATPS) messages is disclosed. The algorithm is based on the modified parity test. The information included in the decoded messages can be used for the high level differential SATPS testing.
Direct integrated approach to multipath signal identification
Granted: December 14, 1999
Patent Number:
6002361
Method and apparatus for improving the accuracy of a received composite signal s(t) that contains a known reference signal S.sub.d (t) with a known bit transition period .DELTA.tchip and that may contain a multipath signal S.sub.m (t;.chi.;b) with an unknown multipath time delay b and an unknown multipath gain factor .chi. (-1.ltoreq..chi..ltoreq.1). Autocorrelation functions AC(.tau.) and AC(.tau.;d) for the incoming signal and for the reference (direct) signal are determined, dependent…
Determination of radar threat location from an airborne vehicle
Granted: December 7, 1999
Patent Number:
5999130
A method for estimating the location of the source of a (possibly unfriendly) electromagnetic probe signal (threat radar) received by an aircraft as the aircraft moves along a chosen path. A signal direction finder on the aircraft determines geometric parameters describing a probe signal plane that contains a probe signal propagation direction, as received at the aircraft, at two or more selected times. A location determination system on the aircraft determines the location of the…
Optimal ring antenna determination system
Granted: November 30, 1999
Patent Number:
5995917
A system and method for determining the minimum number of radiating elements required to achieve desired operating characteristics for a circular array of radiating elements. In one embodiment, the present invention determines the number of radiating elements required to space the radiating elements about the periphery of a circle such that a circular array of radiating elements is generated. The radiating elements are spaced apart from each other by a distance which is related to the…
Navigation system incorporating simplified location display
Granted: November 23, 1999
Patent Number:
5991690
A method and apparatus for providing navigation information including a simplified location display. The mobile unit includes a GPS position determination system including a GPS antenna, a GPS receiver, and a GPS processor. The system also includes a microprocessor and a database storage device. A map database is stored in the database storage device. In operation, the simplified location display system continually displays the travel path and location along the travel path that…
Geometric utilization of exact solutions of the pseudorange equations
Granted: November 16, 1999
Patent Number:
5986603
Method and apparatus for determining non-iterative exact solutions for two, three or four location fix coordinates x, y, z and/or time offset b from pseudorange measurements from a plurality of location determination (LD) signals received at a GPS or GLONASS station. If M location fix coordinates are to be determined from N pseudorange measurements, the solution is exact if N=M. If N=M-1, the solution for two of the location fix coordinates lies at a point, on an ellipse or on an…
Survey coordinate transformation optimization
Granted: November 16, 1999
Patent Number:
5986604
A system for selecting an optimal transformation T(G2;G1) between a first ellipsoid E1 (e.g., WGS 84) in a first global coordinate system G1, relative to which the survey measurements are made, and a second ellipsoid E2 (e.g., NAD 27) in a second global coordinate system G2. Location coordinates (x'.sub.m,2,y'.sub.m,2,z'.sub.m,2) for M previously-surveyed locations, numbered m=1, . . . , M (M>1) in the second system, and location coordinates (x'.sub.n,1,y'.sub.n,1,z'.sub.n,1) for N…
Antenna with ground plane having cutouts
Granted: November 16, 1999
Patent Number:
5986615
An antenna structure has a radiating element and a ground plane. The ground plane has a central region relatively closely spaced apart from the radiating element and a peripheral region extending away from the central region. The peripheral region comprises at least the conductive layer that extends radially beyond the radiating element and provides a sheet resistivity higher than that of the radiating element. Though physically small, the ground plane simulates an infinite ground plane,…
Method and apparatus for correction of GPS carrier phase measurement
Granted: November 16, 1999
Patent Number:
5987084
The output phase measures output by a digital phase lock loop (DPLL) are selectively modified to reduce instantaneous phase errors incurred whilst waiting until the DPLL locks before obtaining an accurate phase measurement of a signal. In one embodiment, the output phase of a low bandwidth DPLL is selectively modified when the input signal exhibits a significant dynamic transient by adding the error term generated by the DPLL phase detector to the output signal generated by the DPLL to…
Image authentication patterning
Granted: November 16, 1999
Patent Number:
5987136
Apparatus for producing a self-authenticating visual image of a selected view, using a digital image forming means, such as a digital camera, together with a position determining system that provides position information, including location and/or angular orientation and/or time of observation at the time a digital image is formed and/or distance from the camera to a selected object. The digital image of the selected view is presented as an array of pixels with associated pixel values.…
Vehicle tracker mileage-time monitor and calibrator
Granted: November 16, 1999
Patent Number:
5987378
A system for monitoring location and speed of a vehicle, using a location determination system such as GPS, GLONASS or LORAN and an optional odometer or speedometer, for determining and recording the locations and times at which vehicle speed is less than a threshold speed for at least a threshold time (called a "vehicle arrest event"). Vehicle arrest event locations, times and time intervals are stored and/or printed to provide trip and mileage records and for efficiency monitoring. A…
Creation and monitoring of variable buffer zones
Granted: November 16, 1999
Patent Number:
5987379
A system for monitoring operation and location of a movable entity, such as a person, vehicle, movable equipment item or movable structure, at an activity site, such as a construction or mining site, that carries a location determination (LD) signal module to determine the entity's present location. When a restricted or hazardous activity occurs without warning (emergency) or is scheduled to occur at a selected location (fixed or moving) and selected time interval on the site, a buffer…
