# US 5,351,045 A · Low-level wind-shear alert system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,351,045 A - Document ID: US5351045A - Status: Granted - Kind: A - Application number: 07/851,466 - Filed: 1992-03-13 - Granted: 1994-09-27 - Earliest claimed: 1991-06-19 - Assignees: University Corporation for Atmospheric Research - Inventors: Lawrence B. Cornman - Web page: https://patentgrep.com/patent/US5351045A ## CPC - G01P 5/00: Measuring speed of fluids, e.g. of air stream; Measuring speed of bodies relative to fluids, e.g. of ship, of aircraft (application of speed-measuring devices for measuring volume of fluid G01F) - G01S 7/003: {Transmission of data between radar, sonar or lidar systems and remote stations} - G01S 13/86: Combinations of radar systems with non-radar systems, e.g. sonar, direction finder - G01S 13/951: {ground based} - Y02A 90/10: Information and communication technologies [ICT] supporting adaptation to climate change, e.g. for weather forecasting or climate simulation - G01P: MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT (measuring or recording blood flow A61B5/02, A61B8/06; monitoring speed or deceleration of electrically-propelled vehicles B60L3/00; vehicle lighting systems adapted to indicate speed B60Q1/54; determining position or course in navigation, measuring ground distance in geodesy or surveying G01C; combined measuring devices for measuring two or more variables of movement G01C23/00; measuring velocity of sound G01H; measuring velocity of light G01J7/00; measuring direction or velocity of solid objects by reception or emission of radiowaves or other waves and based on propagation effects, e.g. Doppler effect, propagation time, direction of propagation, G01S; measuring speed of nuclear radiation G01T; measuring acceleration of gravity G01V; {measuring or recording the speed of trains B61L23/00; speed indicators incorporated in motor vehicles B60K35/00; measuring frequency or phase G01R; traffic control G08G}) - G01S: RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES - Y02A: TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE ## Abstract The apparatus of the present invention improved low-level wind shear alert system that provides an improved method of identifying the presence and locus of wind shear in a predefined area. This system enhances the operational effectiveness of the existing LLWAS system by mapping the two-dimensional wind velocity, measured at a number of locations, to a geographical indication of wind shear events. This system can also integrate data and processed information received from a plurality of sources, such as anemometers and Doppler radar systems, to produce low-level wind shear alerts of significantly improved accuracy over those of prior systems. In particular, the apparatus of the present invention makes use of the data and processed information produced by the existing Low-Level Wind Shear Alert System as well as that produced by the Terminal Doppler Weather Radar to precisely identify the locus and magnitude of low-level wind shear events within a predetermined area. This resultant geographical indication is displayed in color-graphic form to the air traffic control personnel and can also be transmitted via a telemetry link to aircraft in the vicinity of the airport for display therein. ## Claims ### Claim 1 A method of identifying the presence and locus of wind shear in a predefined area based on wind measurements taken at a plurality of wind sensing loci located in said predetermined area, each of said measurements being indicative of a wind magnitude and direction at a corresponding one of said loci said method comprising the steps of: collecting said wind measurements from said plurality of loci; producing wind shear shape data indicative of the bounds of a wind shear event within said predetermined area based on said collected wind measurements to identify the presence and locus of wind shear in said predefined area, comprising: creating a grid having a plurality of points that maps said predetermined area into said plurality of points, converting each of said wind measurements taken at said plurality of wind sensing loci into divergence values indicative of wind divergence at each of said plurality of wind sensing loci, as computed between selected pairs and triples of said wind sensing loci; mapping each of said divergence values onto said grid to create corresponding wind data points, each of which has a value representative of a wind divergence at a corresponding one of said plurality of points in said predetermined area, deleting all said mapped wind data points whose mapped value does not exceed a predetermined threshold from said grid, and bounding all contiguous ones of said mapped wind data points that remain in said grid following said step of deleting within a boundary of predetermined shape to identify the presence and locus of a wind shear event. ### Claim 2 (depends on 1) The method of claim 1 further including the step of: storing runway template data indicative of the locus of at least one airport runway in said predefined area; and mapping said identified wind shear locus to said runway template data to denote said identified wind shear locus with respect to said at least one runway. ### Claim 3 (depends on 2) The method of claim 2 further including the step of: generating a wind shear alert, in response to said identified wind shear locus being within a predetermined distance from said at least one airport runway, which wind shear alert denotes a runway specific wind shear indication. ### Claim 4 (depends on 1) The method of claim 1 wherein said step of producing further includes: reducing the area of said grid encompassed by said boundary by translating and shrinking the extent of said boundary while retaining said predetermined shape. ### Claim 5 (depends on 4) The method of claim 4 wherein said step of producing further includes: comparing the magnitude of said bounded mapped wind data points with a predetermined threshold; deleting said bounded mapped wind data points that fail to exceed said predetermined threshold; and validating said bounded mapped wind data points as a valid wind shear event if said bounded mapped wind data points correspond to previously identified valid wind shear events. ### Claim 6 (depends on 5) The method of claim 5 wherein said step of validating includes: determining whether said bounded mapped wind data points are temporally related to a collocated previously occurring identified valid wind shear event within a predetermined elapsed time. ### Claim 7 (depends on 5) The method of claim 5 wherein said step of validating includes: determining whether said bounded mapped wind data points are spatially related to a previously occurring valid wind shear event within a predetermined distance between a locus on said grid of said bounded mapped wind data points and a locus on said grid of said previously occurring valid wind shear event. ### Claim 8 (depends on 4) The method of claim 4 wherein said predetermined shape comprises a band-aid shape, said step of reducing includes: computing an axis through said wind data points; selecting a radius for both end points of said axis such that the semicircles drawn at the end points using said radius, when joined by straight line segments parallel to said axis, encircle all said wind data points and encompasses the minimum area of said grid. ### Claim 9 (depends on 8) The method of claim 8 wherein said step of computing creates a weighted least squares line through said wind data points. ### Claim 10 Apparatus for identifying the presence and locus of wind shear in a predefined area based on wind measurements taken at a plurality of wind sensing loci located in said predetermined area, each of said measurements being indicative of a wind magnitude and direction at a corresponding one of said loci, said method comprising: means for collecting said wind measurements from said plurality of loci; means for producing wind shear shape data indicative of the bounds of a wind shear event within said predetermined area based on said collected wind measurements to identify the presence and locus of wind shear in said predefined area, comprising: means for creasing a grid having a plurality of points that maps said predetermined area into said plurality of points, means for converting each of said wind measurements taken at said plurality of wind sensing loci into divergence values indicative of wind divergence at said plurality of loci, as computed between selected pairs and triples of said wind sensing loci; means for mapping each of said wind measurements onto said grid to create corresponding wind data points, each of which has a value representative of a wind divergence at a corresponding one of said plurality of points in said predetermined area, means for deleting all said mapped wind data points whose mapped value does not exceed a predetermined threshold from said grid, and means for bounding all contiguous ones of said mapped wind data points that remain in said grid within a boundary of predetermined shape to identify the presence and locus of a wind shear event. ### Claim 11 (depends on 10) The apparatus of claim 10 further including: means for storing runway template data indicative of the locus of at least one airport runway in said predefined area; and means for mapping said identified wind shear locus to said runway template data to denote said identified wind shear locus with respect to said at least one runway. ### Claim 12 (depends on 11) The apparatus of claim 11 further including: means for generating a wind shear alert, in response to said identified wind shear locus being within a predetermined distance from said at least one airport runway, which wind shear alert denotes a runway specific wind shear indication. ### Claim 13 (depends on 10) The apparatus of claim 10 wherein said producing means further includes: means for reducing the area of said grid encompassed by said boundary by translating and shrinking the extent of said boundary while retaining said predetermined shape. ### Claim 14 (depends on 13) The apparatus of claim 13 wherein said producing means further includes: means for comparing the magnitude of said bounded mapped wind data points with a predetermined threshold; means for deleting said bounded mapped wind data points that fail to exceed said predetermined threshold; and means for validating said bounded mapped wind data points as a valid wind shear event if said bounded mapped wind data points correspond to previously identified valid wind shear events. ### Claim 15 (depends on 14) The apparatus of claim 14 wherein said validating means includes: means for determining whether said bounded mapped wind data points are temporally related to a collocated previously occurring identified valid wind shear event within a predetermined elapsed time. ### Claim 16 (depends on 14) The apparatus of claim 14 wherein said validating means includes: means for determining whether said bounded mapped wind data points are spatially related to a previously occurring valid wind shear event within a predetermined distance between a locus on said grid of said bounded mapped wind data points and a locus on said grid of said previously occurring valid wind shear event. ### Claim 17 (depends on 13) The apparatus of claim 13 wherein said predetermined shape comprises a band-aid shape, said reducing means includes: means for computing an axis through said wind data points; means for selecting a radius for both end points of said axis such that the semicircles drawn at the end points using said radius, when joined by straight line segments parallel to said axis, encircle all said wind data points and encompasses the minimum area of said grid. ### Claim 18 (depends on 17) The apparatus of claim 17 wherein said computing means creates a weighted least squares line through said wind data points.