Projection of multi-sensor ray based data histories onto planar grids

• US 6,400,313 B1
• Filed: 10/02/2000
• Issued: 06/04/2002
• Est. Priority Date: 01/12/2000
• Status: Expired due to Fees

• Current Assignee: Honeywell International Inc.
• Original Assignee: Honeywell International Inc.
• Inventors: Brinsley, James R., Morici, Martin M.
• Primary Examiner(s): Sotomayor, John B.
• Application Number:
  US09/677,154
• Time in Patent Office: 610 Days
• Field of Search: 342/176, 342/179, 342/180, 342/185, 342/195, 342/197, 345/419, 345/420, 345/421, 345/427, 345/438, 345/473, 345/474, 345/581, 345/630, 345/953, 345/958
• US Class Current: 342/176
• CPC Class Codes: G01S 13/87 Combinations of radar systems, e.g. primary radar and secondary radar
• CPC Class Codes: G01S 13/95 for meteorological use
• CPC Class Codes: G01S 7/003 Transmission of data between radar, sonar or lidar systems and remote stations
• CPC Class Codes: G01S 7/20 Stereoscopic displays; Three-dimensional displays; Pseudo-three-dimensional displays
• CPC Class Codes: G01S 7/2955 Means for determining the position of the radar coordinate system for evaluating the position data of the target in another coordinate system G01S7/24 takes precedence; sighting devices adapted for indirect laying of fire F41G3/16; inertial navigation G01C21/16
• CPC Class Codes: Y02A 90/10 Information and communication technologies [ICT] supporting adaptation to climate change, e.g. for weather forecasting or climate simulation
• CPC Class Codes: Y10S 345/958 Collision avoidance

Abstract

A method and apparatus which perform efficient projection of 4-dimensional data (3 spatial and 1 time dimension) onto planar grids are described. Multiple frames of data are drawn from a limited time history data buffer and projected onto a planar grid, which need not be flat, defined in its own coordinate system. Higher dimensional data structures can also be formed from multiple projection grids. Measurement data from multiple data frames is projected into the planar grid such that distance out of plane is the z-dimension. Computational efficiency is achieved by processing only those data samples that are relevant to the planar grid. To be considered relevant, the impulse response of the sensor'"'"'s measurement rays must cross the planar grid. Samples of relevant rays must also map onto the planar grid'"'"'s coordinate mesh to be relevant. Multiple data measurements may determine the planar grid'"'"'s final amplitude result. Amplitudes at the planar grid coordinates are determined by the most relevant measurement(s) of those within the extent of the measurement system'"'"'s impulse response.

Claims

1. An apparatus for use in a radar system for transforming data into planar grid for display, said apparatus comprising:

a plurality of sensors for collecting data;

a frame generator which receives data collected by the sensors and transforms the data into individual data frames for further processing;

a database which receives the data frames from said frame generator;

an input device for receiving requests from a user for a planar grid of interest;

a CPU which, in response to instructions received from the input device, (i) requests data frames of interest from said database for display, (ii) transforms the data frames of interest to a common coordinate system, (iii) filters the data frames of interest for relevance to the planar grid of interest, and (iv) marks data frames identified as relevant; and

a display for presenting the planar grid of interest based on the data frames marked as relevant.

2. An apparatus for transforming data into display grids as described in claim 1, wherein:

the planar grid of interest is rotated and translated into a grid formation system;

the data frames of interest are mapped to the grid formation system;

all rays of each data frame are constructed and projected to the grid formation system; and

a ray is marked as relevant if the ray crosses the x-y plane of the grid formation system.

3. An apparatus for transforming data into display grids as described in claim 2, wherein:

each data gate of a ray marked as relevant is further marked as relevant if said data gate is within one beamwidth of the x-y plane of the grid formation system.

4. An apparatus for transforming data into display grids as described in claim 3, wherein:

each grid cell of the grid formation system within one beamwidth box of each data gate marked as relevant is identified;

each identified grid cell is compared with each data gate marked as relevant to determine if the grid cell is within one range gate and one beamwidth of the data gate; and

,

the most relevant data gate is identified.

5. An apparatus for transforming data into display grids as described in claim 4, wherein the amplitude of the most relevant data gate is determined and the data is transformed onto the planar grid for display.

6. A method for use in a radar system for transforming data into planar grid for display, said method comprising the steps of:

(1) collecting data from a plurality of sensors;

(2) transforming the data into individual data frames for further processing;

(3) storing the data frames in a database;

(4) receiving a request from a user for a planar grid of interest;

(5) requesting data frames of interest from said database for display;

(6) transforming the data frames of interest to a common coordinate system;

(7) filtering the data frames of interest for relevance to the planar grid of interest;

(8) marking the data frames identified as relevant; and

(9) displaying the data frames marked as relevant on a planar grid.

7. The method for transforming data into display grids as described in claim 6, further comprising the steps of:

rotating an translating the planar grid of interest into a grid formation system;

mapping the data frames of interest to the grid formation system;

constructing and projecting all rays of each data frame to the grid formation system; and

marking a ray as relevant if the ray crosses the x-y plane of the grid formation system.

8. The method for transforming data into display grids as described in claim 7, further comprising the steps of:

marking each data gate of a ray marked as relevant as further relevant if said data gate is within one beamwidth of the x-y plane of the grid formation system.

9. The method of transforming data into display grids as described in claim 8, further comprising the steps of:

identifying each grid cell of the grid formation system within one beamwidth box of each data gate marked as relevant;

comparing each identified grid cell with each data gate marked as relevant to determine if the grid cell is within one range gate and one beamwidth of the data gate; and

,

identifying the most relevant data gate.

10. The method of transforming data into display grids as described in claim 9, further comprising the steps of:

determining the amplitude of the most relevant data gate;

transforming the data onto the planar grid for display; and

identifying display grids which do not contain information.