Abstract: A method for estimating two or three location coordinates and/or receiver time offset for a receiver that receives and analyzes timed signals transmitted from one, two or three non-geosynchronous satellites (GPS, GLONASS, modified LEO, etc.). Combinations of pseudorange, Doppler shift and/or first time derivative and/or second time derivative of Doppler shift are determined and used to estimate the location coordinates and/or receiver time offset.

Abstract: A system for monitoring operation and location of a moving first vehicle relative to a second vehicle. A minimum separation distance between the first and second vehicles is estimated, based on the first vehicle velocity, and optionally on the second vehicle velocity, using location determination (LD) signals received from satellite-based transmitters from GPS, GLONASS and LEO satellites, or from ground-based signal sources such as LORAN signal towers, and using ranging signals from SONAR, RADAR or a similar system. The minimum separation distance is compared with the actual separation distance at selected times, and a vehicle driver is advised if the actual separation distance is too small, if the separation distance is decreasing too quickly, or if the second vehicle velocity is decreasing too quickly. The second vehicle may travel in the same traffic lane, in an adjacent lane, or on a road that intersects the road used by the first vehicle.

Abstract: Methods for estimation of the relative locations (baseline vectors) of two or more GPS signal antennas relative to each other and for estimation of line biases associated with each signal processing channel associated with each GPS signal antenna. Double difference carrier phase signal measurements are formed, using floating integer and fixed integer solutions for the phase integer ambiguities, and baseline vectors between the GPS signal antennas are estimated. Single difference phase integer ambiguities are obtained and approximations for line biases are computed. Single difference carrier phase measurements are used to estimate baseline vectors and line biases, using fixed phase integer ambiguities with the estimated baseline vectors and line biases as initial conditions, and are processed by Kalman filtering or other suitable signal processing. Angular orientation or attitude of a vehicle body on which the GPS signal antennas are placed is determined from the baseline vectors.

Abstract: Methods for GPS-assisted determination of location coordinates of a mobile user or selected position on or adjacent to the Earth's surface with improved accuracy. Elevation readings from an altimeter or barometer are integrated with readings of the GPS-determined elevation coordinate for that location, using Kalman filter techniques, minimum least square techniques, or comparison of certain statistically defined parameters associated with the altimeter and GPS variables, such as the standard deviation of the expected errors in these variables. The resulting elevation coordinate may be a statistical blend or filtered blend of the altimeter value and a GPS-determined value for the elevation coordinate; or this resulting elevation coordinate can be chosen to be one or the other of these values, based upon comparison of time varying statistical parameters corresponding to the altimeter and the GPS.

Abstract: Method [and apparatus ] for quickly and controllably removing chemical residues and particle accumulations from an exposed surface of an object. A slurry, containing a slurry liquid and containing small scrubber particles that optionally have a range of at least two distinct particle sizes, is directed at the exposed surface to remove most or all of the residues and accumulations from the exposed surface. The slurry flow may be pulsed or be relatively constant. The exposed surface of the object is then partly or fully submerged in a rinse liquid that includes a strong base and/or a strong oxidizing agent. The rinse liquid is subjected to ultrasonic wave motion with a chosen wave displacement direction, and the ultrasonic waves have one or more distinct wavelengths, chosen to cover a range of expected sizes of chemical residues, particle accumulations and/or scrubber particles to be removed.

Abstract: 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. The position information is incorporated in the digital image by altering selected pixel bit values for a selected authentication pattern P of pixels in a chosen subset CS of the pixel array; and this selected pattern may be determined using the position information. The position information may be encrypted, using an encryption key based on position information, and may be stored separate from, or as part of, the digital image.

Abstract: Method and apparatus for determining the location of a point on a rotating body, using location determination (LD) signals received from as few as one satellite, preferably non-geosynchronous. Where signals from two or more satellites are received, one may be geosynchronous. Pseudoranges are measured from one or more satellites at two or more selected, spaced apart observation times, and the simultaneous rotations of the body and the satellite(s) relative to each other result in different body-satellite constellations for which the initial location coordinates (and, optionally, signal receiver time offset) of the selected point are determined exactly, without approximation or iteration. The selected point may be motionless or may be allowed to move with known coordinate differences between the initial unknown location and the present location at each observation time. Pseudoranges from different satellites, or even from different satellite systems (GPS, GLONASS, LEO, etc.

Abstract: Method and apparatus for drying and/or cleaning a workpiece, such as an electronic part, semiconductor wafer, printed circuit board or the like. As the workpiece is withdrawn from a processing liquid, a selected drying liquid, such as hydrofluoroether (HFE) or an HFE azeotrope, that has a very small surface tension, is volatile, and has a density that is greater than the processing liquid density, is sprayed on, dribbled on or otherwise transferred to an exposed surface of the workpiece. The workpiece can be dried in 7-45 seconds, or less, in most situations and can be cleaned using the invention. Drying and/or cleaning can be performed in a single workpiece process, a single workpiece continuous process or a batch process.

Abstract: A system for improving the accuracy of location coordinate determined in a survey of a chosen region, using a computer. A grid of spaced apart points is imposed on the region, and a set of survey control points is provided. A "near set" of nearest survey control points is associated with each grid point. For each grid point, a transformation T from a first (global) datum and coordinate system to a second (local) datum and coordinate system is determined that minimizes a collective difference between coordinates of each survey control point in the near set and the corresponding coordinates of that survey control point under the transformation T. For one, two or three coordinates of each grid point, a difference .DELTA. between the coordinate(s) of the grid point in the near set and the corresponding coordinate(s) of that grid point under the transformation T is computed. An interpolation function is determined that approximately matches the coordinate(s) difference .DELTA. at each grid point.

Abstract: Methods for cleaning and/or drying objects that may have been wetted or contaminated in a manufacturing process. The objects are submerged in a rinse liquid in an enclosed chamber, and aerosol particles from a selected liquid are introduced into the chamber above the rinse liquid surface, forming a thin film on this surface. As the rinse liquid is slowly drained, some aerosol particles settle onto the exposed surfaces of the objects, and displace and remove rinse liquid residues from the exposed surfaces, possibly by a "chemical squeegeeing" effect. Surface contaminants are also removed by this process which may be performed at about room temperature. Chamber pressure is maintained at or near the external environment pressure as the rinse liquid is drained from the chamber. Inert gas flow is employed to provide aerosol particles of smaller size and/or with greater dispersion within the chamber. Continuous filtering and shunt filtering are employed to remove most contaminants from the selected liquid.

Abstract: Methods for drying and cleaning objects that may have been wetted or contaminated in a manufacturing process. The objects are submerged in a rinse liquid in an enclosed chamber, and aerosol particles from a selected liquid are introduced into the chamber above the rinse liquid surface, forming a thin film on this surface. As the rinse liquid is slowly drained, some aerosol particles settle onto the exposed surfaces of the objects, and displace and remove rinse liquid residues from the exposed surfaces, possibly by a "chemical squeegeeing" effect. Surface contarminants are also removed by this process, which may be carried out at or near room temperature. Chamber pressure is maintained at or near the external environment pressure as the rinse liquid is drained from the chamber.

Abstract: Apparatus and method for determining the present location of a mobile user that carries the apparatus inside or outside buildings and structures within a region R. The apparatus includes a radio location determination (LD) signal module that receives radiowaves from at least three radio LD signal sources, such as FM carrier or subcarrier signals, and an outdoor LD signal module that receives outdoor LD signals from at three other satellite-based or ground-based outdoor LD signal sources, such as GPS, GLONASS or Loran-C signal sources. The radio LD signals and outdoor LD signals are used to (1) determine the location of the radio LD module, (2) determine the location of the outdoor LD module and (3) determine an indicium representing signal strength or signal quality for the radio LD signals and for the outdoor LD signals.

Abstract: A method for fast acquisition, in as little as 6-15 seconds, of signals from a satellite in a Satellite Positioning System (SATPS), such as GPS or GLONASS, that does not require permanent storage of satellite ephemeris information at an SATPS ground station. This SATPS signal acquisition method can be used whenever the "new" station initially powers up or has lost lock on one or more SATPS signals that must be (re)acquired. A reference SATPS station provides the new SATPS station with an estimated reference station location and ephemeris information for one or more identified SATPS satellites visible from the reference station. The new station receives and uses this information to establish carrier frequency ranges to search for the identified SATPS satellite, by limiting the search to a reduced frequency range based upon estimated Doppler shift of SATPS signals received from this satellite.

Abstract: A system for determining exact solutions of the pseudorange equations obtained from measurements of location determination (LD) signals received from N LD signal sources by a mobile LD station. The LD signal sources may be part of a GPS, a GLONASS, LEO or any other satellite-based or ground-based LD system, such as Loran. Squares of differences of the pseudorange equations are subtracted from each other to produce N-1 linear relations between the unknown location coordinates x, y and z and the receiver clock offset b. These linear relations are used in one or more squares of pseudorange equations to produce a quadratic equation in b, or in x, y or z. A physically realistic solution b is found and used to determine the remaining unknown coordinates (x,y,z). No iteration or approximation is required. For N.gtoreq.5, the approach extends to situations where the clock offset varies with time. For N.gtoreq.

Abstract: Method and apparatus for processing a workpiece in a chemical bath liquid contained in a liquid container. The liquid container is fabricated from a material such as polyetheretherketone (PEEK), poly-amide-imide (PAI) or polyphenylene sulfide (PPS). A vibration generator is positioned on each of one or more container walls to introduce vibrations with a selected frequency (20-750 kHz) through the container wall(s) and into the chemical bath liquid. Two or more vibration generators may introduce vibrations with different frequencies into the chemical bath liquid and at different angles. The chemical bath liquid may be an acid such as HCl, H.sub.2 SO.sub.4, HNO.sub.3, H.sub.2 PO.sub.3 and HF, or may be an oxidizer or base such as NH.sub.4 OH and H.sub.2 O.sub.2. The chemical bath may be used to process semiconductor wafers and circuits, printed circuit boards, optical components and similar workpieces.

Abstract: Method and apparatus for providing GPS pseudorange correction information over a selected geographic region S with a diameter of up to 300 km with an associated inaccuracy no greater than 5 cm. N spaced apart GPS reference stations (N>4), whose location coordinates (u.sub.n,v.sub.n,w.sub.n) are fixed and are known with high accuracy, are provided within or adjacent to the region R. Each reference station n(n=1, 2, . . . , N) receives GPS signals from at least four common-view GPS satellites, numbered m=1, 2, . . . , M (M.gtoreq.4), computes its own GPS-determined location coordinates, compares these coordinates with its known location coordinates, determines the pseudorange corrections PRC(t;t0;m;n) for its GPS-determined location, and transmits these correction signals to a central station located within or adjacent to the region S. The central station retransmits the pseudorange correction signals throughout the region S.

Abstract: Method and apparatus for monitoring present location of a person ("confinee") who is to be confined to a designated site, which site can have a diameter as small as a few meters or as large as several kilometers. The present location of the confinee is checked at selected time intervals with time periods ranging from one second to thousands of seconds, as desired. The confinee wears a location-determining ("LD") unit that receives electromagnetic signals that contain information allowing determination of the present location of the LD unit, and thus of the confinee, from three or more non-collinear outdoor LD signal sources and from three or more non-collinear indoor LD signal sources. The indoor LD signal sources may be radiowave transmitters. The outdoor LD signal sources may be transmitters for a Loran, Omega, Decca, Tacan, JTIDS Relnav or PLRS or similar ground-based system, or transmitters for a satellite positioning system, such as GPS or GLONASS.

Abstract: Methods for synchronizing to a reference signal the timing of a received composite, code phase SATPS signal, which consists of a preferred, interference-free signal distorted by at least one interfering signal, to determine an undistorted timing point of the preferred signal. An idealized correlation function A.sub.I (t), formed from the product of a digital reference signal with a time-shifted reference signal, and a measured correlation signal A.sub.M (t), formed from the product of a received signal and a time-shifted reference signal, are computed. Peak amplitudes A.sub.M (.sub.pM) and A.sub.I (.sub.pI) are found for the respective measurable and idealized punctual code phase shifts .sub.pM and .sub.pI. The correlation measurements formed on the early side (or on the late side) of the peak for the correlation function A(t) are combined to form an estimate of the time delay associated with a multipath signal.

Abstract: A system for selection by a user and delivery to the user of selected audio data files at a delivery rate of 2-100 times the delivery rate for normal, audibly perceptible playback of an audio data file. The user registers the user's selection of audio material with a central library of data files and a digitized and compressed omnibus file containing the user's selections is prepared and transmitted to the user at a high data transfer rate. The user receives downloads the omnibus file to a removable, high density diskette or PCMCIA card that may hold ten ?Mbytes! Megabytes to one ?Gbyte! Gigabyte of digitized text or audio data, using a removable hard drive or its equivalent and a universal data interface that recognized and compensates for omnibus files received in any of a plurality of input signal formats. The user carries this diskette or PCMCIA card until the user has an opportunity to decompress and play back the text or audio data files in audibly perceptible form.

Abstract: Methods for determining integrity of pseudorange and pseudorange rate signals received from a plurality of M Satellite Positioning System satellites (including GPS and GLONASS), numbered j=j1, j2, . . . , jM, at a reference SATPS station (RS), using pseudorange or pseudorange rate signals received from the same satellites at a nearby signal integrity monitoring (SIM) station. Pseudorange correction values or, alternatively, pseudorange rate correction values, for SATPS signals received at an RS station and at the corresponding SIM station are computed, and difference values between the RS and SIM values are computed for each satellite. If the magnitude of each difference is less than a selected threshold difference, pseudorange corrections or pseudorange rate corrections for that reference station can be used by a nearby mobile station to differentially correct the mobile station location fix coordinates or velocity fix coordinates.