Method and Software for Spatial Pattern Analysis

• US 20090284426A1
• Filed: 12/31/2008
• Published: 11/19/2009
• Est. Priority Date: 05/15/2008
• Status: Active Grant

• Current Assignee: the united states of america as represented by the secretary of the navy
• Original Assignee: the united states of america as represented by the secretary of the navy
• Inventors: Baker, Carl, Carlson, Terry, Schumm, Michael, Shaff, William L., Snow, Jeffrey M.
• Granted Patent: US 8,421,673 B2
• Time in Patent Office: Days
• US Class Current: 343/703
• CPC Class Codes: G01R 29/10 Radiation diagrams of antennas

Abstract

A method and software implementation for spatial pattern analysis. A user-guided test procedure is implemented to measure features of an antenna under test to determine the antenna'"'"'s far-field patterns. The antenna features include RF amplitude or phase, and position and orientation relative to a receiving object.

Claims

1. A method for spatial pattern analysis, comprising the steps of:

inputting configuration data pertinent to a test into a database, said configuration data including,

a parametric profile of each object involved in said test inclusive of a transmitting object and a receiving probe, and

dimensional offsets of said transmitting object relative to said receiving probe,

defining a test plan including a plurality of test points of said transmitting object relative to said receiving probe and a test sequence for measurement at said test points;

moving a movable object coupled to one of said transmitting object and said receiving probe between said test points;

implementing said test plan by measuring test data, a position of said movable object and an orientation of said movable object at each test point;

determining from said measured position and orientation, a coordinate location of said one of said transmitting object and said receiving probe;

storing said measured test data and said coordinate location; and

displaying a graphical user interface including a graphical representation of said transmitting object, said receiving probe, said test points, and progress of said measuring.

2. The method for spatial pattern analysis according to claim 1, wherein said step of determining from said measured position and orientation a coordinate location further comprises a translating said measured position and orientation into an exact coordinate location using a rotational matrix.

3. The method for spatial pattern analysis according to claim 1, wherein said step of measuring a position of said movable object further comprises measuring a GPS position of said movable object.

4. The method for spatial pattern analysis according to claim 3, wherein said step of measuring a GPS position of said movable object further comprises measuring an RTK/GPS position of said movable object.

5. The method for spatial pattern analysis according to claim 1, wherein said step of measuring an orientation of said movable object further comprises measuring azimuth, pitch, and roll of said movable object.

6. The method for spatial pattern analysis according to claim 5, wherein said step of measuring azimuth, pitch, and roll of said movable object is accomplished with an inertial navigation unit.

7. The method for spatial pattern analysis according to claim 1, wherein said test data comprises RF amplitude data.

8. The method for spatial pattern analysis according to claim 7, wherein said test data comprises RF phase data.

9. The method for spatial pattern analysis according to claim 7, wherein said step of measuring RF amplitude data further comprises time-stamping said test data.

10. The method for spatial pattern analysis according to claim 1, wherein said step of moving said movable object further comprises providing a graphical user interface to guide an operator to move said movable object between said test points.

11. The method for spatial pattern analysis according to claim 10, wherein said step of moving said movable object further comprises displaying in said graphical user interface directional information to guide said operator to move said movable object from a first test point location to a second test point location, wherein said first and second test point locations are based on said test sequence.

12. The method for spatial pattern analysis according to claim 1, wherein said step of moving said movable object further comprises providing a next test point location to a mechanical device adapted to move said movable object from a present location to said next test point location, wherein said next test point location is based on said test sequence.

13. The method for spatial pattern analysis according to claim 1, wherein said objects involved in said test include one or more of said transmitting object, said receiving probe, said movable object, a GPS sensor for measuring said GPS position of said movable object, and said inertial navigation unit.

14. The method for spatial pattern analysis according to claim 1, wherein the step of defining a test plan including a plurality of test points comprises inputting a pattern into the database and computing locations of said test points based on said pattern.

15. The method for spatial pattern analysis according to claim 14, further including inputting a number of test points, wherein said computing of said locations is based on said number of test points.

16. The method for spatial pattern analysis according to claim 14, further including inputting a distance between test points, wherein said computing of said locations is based on said distance between said test points along said pattern.

17. The method for spatial pattern analysis according to claim 1, wherein the step of defining a test plan including a plurality of test points comprises positioning said movable object at a location, measuring a position and an orientation of said movable object at said location, and adding a test point to said test plan corresponding to said position and orientation measurements.

18. The method for spatial pattern analysis according to claim 1, wherein the step of defining a test plan including a plurality of test points comprises inputting radial parameters including a starting angle, an ending angle, a starting distance and an ending distance from a center of said transmitting object, and a distance between test points, and computing said test points based on said radial parameters.

19. Software for spatial pattern analysis, comprising:

a database including a plurality of predefined objects, a parametric profile of each said object, dimensional offsets of said objects, a plurality of test points, and a test sequence for measurement at said test points, said objects including a transmitting object and a receiving probe;

a software module for calculating a test plan based on said database;

software for generating a graphical user interface for guiding an operator to move said one of said receiving probe and said transmitting object between said test points;

software for implementing said test plan by measuring test data, a position of an object and an orientation of said object at each test point, and for time-stamping and storing each measured data set;

software for determining from said stored data sets an actual coordinate location of said test points;

software for displaying a graphical user interface comprising a graphical representation of said predefined objects and progress of said test plan implementation.

20. The software for spatial pattern analysis according to claim 19, wherein said software for determining from said stored data sets an actual coordinate location of said test points further comprises a rotational matrix for translating said measured position and orientation into an exact coordinate location.

21. The software for spatial pattern analysis according to claim 19, wherein said software for implementing said test plan by measuring test data measures a GPS position of said object.

22. The software for spatial pattern analysis according to claim 21, wherein said software for implementing said test plan measures an RTK/GPS position of said object.

23. The software for spatial pattern analysis according to claim 19, wherein said software for implementing said test plan measures an azimuth, pitch, and roll of said object.

24. The software for spatial pattern analysis according to claim 19, wherein said software for implementing said test plan measures RF amplitude data.

25. The software for spatial pattern analysis according to claim 19, wherein said software for implementing said test plan measures RF phase data.

26. A computer-readable storage medium storing the software for spatial pattern analysis according to claim 19.

27. A method for testing an antenna system, comprising the steps of:

positioning a probe relative to an antenna under test;

positioning and associating a position sensor and multi-axis orientation sensor relative to one of said probe and antenna under test;

generating test signals from one of said probe and antenna under test and receiving said test signals at the other of said probe or antenna under test;

moving the position sensor, orientation sensor, and associated probe or antenna under test;

sampling an emission pattern and storing data samples therefrom together with associated position data from said position sensor and orientation data from said orientation sensor; and

analyzing said sampled emission pattern and associated position data and orientation data.

28. A method for testing an antenna system according to claim 27, wherein said step of sampling an emission pattern comprises measuring a GPS position of said probe or antenna under test using a GPS position sensor.

29. The method for testing an antenna system according to claim 28, wherein said GPS position sensor comprises an RTK/GPS position sensor.

30. The method for testing an antenna system according to claim 27, wherein said step of sampling an emission pattern comprises measuring azimuth, pitch, and roll of an object.

31. The method for testing an antenna system according to claim 30, wherein said step of measuring azimuth, pitch, and roll of an object comprises measuring orientation of said object using a multi-axis orientation sensor.

32. The method for testing an antenna system according to claim 27, wherein said step of sampling an emission pattern comprises measuring RF amplitude data.

33. The method for testing an antenna system according to claim 27, wherein said step of sampling an emission pattern comprises measuring RF phase data.

34. An antenna test system, comprising:

an RF transmitting object;

an RF receiving object;

a position sensor adapted to determine and output coordinate location data for at least one of said RF transmitting and receiving object;

an orientation sensor adapted to determine and output orientation data for said at least one RF transmitting and receiving object;

a test pattern generator coupled to said RF transmitting object for transmitting a test signal therethrough;

a waveform analyzer coupled to said RF receiving object for determining and storing amplitude data of said received RF test signal;

software for generating a user interface for compiling a test plan including a plurality of test points of said RF transmitting object relative to said receiving object, for implementing said test plan by coordinating timed measurements of said position sensor, orientation sensor, and waveform analyzer, and for generating a graphical spatial representation of said RF transmitting object and RF receiving object inclusive of a progress of said test plan and test results.

35. The antenna test system according to claim 34, wherein said software comprises a plurality of modules including a main module and a plurality of service modules each dedicated to communicating with a driver of said position sensor, orientation sensor, test pattern generator, and waveform analyzer over an-IP based network.

36. The antenna test system according to claim 34 wherein said RF receiving object comprises an RF probe mounted on a roving test station.

37. The antenna test system according to claim 34, wherein said RF transmitting object comprises an RF antenna mounted on a roving test station.

38. The antenna test system according to claim 34, wherein said RF transmitting object comprises an antenna under test coupled to said test pattern generator.

39. The antenna test system according to claim 34, wherein said software compensates said coordinate location data based on the multi-axis orientation data.

40. The antenna test system according to claim 34, wherein said software comprises a rotational matrix for compensating said coordinate location data.

41. The antenna test system according to claim 34, wherein said software for generating a graphical spatial representation presents a graphical user interface that displays an emission pattern for said RF transmitting object.

42. The antenna test system according to claim 34, wherein said software for generating a user interface for compiling a test plan allows an operator to define test equipment, test objects and configurations, test scenarios and sequences, and test frequency plans.

43. The antenna test system according to claim 34, wherein said software for implementing said test plan generates a user interface for guiding a user in placement, movement, and attitude of said RF transmitting object or RF receiving object.

44. A method for testing an RF antenna system, comprising the steps of:

positioning an RF probe relative to an antenna under test;

positioning and associating a GPS/RTK position sensor and multi-axis orientation sensor relative to one of said RF probe or antenna under test;

generating test signals from one of said RF probe or antenna under test and receiving said test signals at the other of said RF probe or antenna under test;

moving the GPS/RTK position sensor, multi-axis orientation sensor, and the associated RF probe or antenna under test;

sampling an emission pattern and storing data samples there from together with associated position data from said GPS/RTK position sensor, and orientation data from said multi-axis orientation sensor; and

analyzing said sampled emission pattern and associated position data and orientation data.

45. A graphical user interface (GUI) adapted to permit a user to create, load and store an RF test plan for spatial pattern analysis of an RF antenna system, said RF test plan comprising:

transmit signal polarization, height, and amplitude; and

receive measurements at a plurality of test points, each said receive measurement being defined by test point location data at each said test point, and test point measurement data including receive frequencies to test for at each test point; and

structural data defining transmit and receive antenna structures, supporting structures, and surrounding terrain.

46. Software for implementing an RF test plan for spatial pattern analysis of an RF antenna system, comprising a plurality of processing sequences, inclusive of:

a first processing sequence adapted to determine location and orientation of a point on a mobile structure based on measurements from a plurality of measurement devices coupled to said mobile structure;

a second processing sequence for creating a database of structural data defining transmit and receive antenna structures, supporting structures, and surrounding terrain.

a third processing sequence for measuring RF amplitude at specified frequencies and specified locations;

a fourth processing sequence for adjusting the specified measurement locations in accordance with said second processing sequence; and

a fifth processing sequence for generating a graphical user interface (GUI) adapted to permit a user to create, load and store said RF test plan for spatial pattern analysis of an RF antenna system.

47. An antenna test system, comprising:

a first processing sequence adapted to display a graphical user interface for allowing a user to load an RF test plan including measurements at a plurality of test points, control implementation of said RF test plan, and initiate acquisition of RF measurement data at said plurality of test points;

a second processing sequence adapted to determine location and orientation data for a plurality of test points;

a third processing sequence adapted to determine position of a GPS measuring device mounted on a mobile test platform;

a fourth processing sequence adapted to control and store measurement data from a spectrum analyzer connected to at least one antenna;

a fifth processing sequence adapted to determine adjusted location and orientation of said at least one antenna based on offsets between said antenna and said GPS measuring device.