Detecting concealed objects at a checkpoint
Disclosed are systems, methods, devices, and apparatus to interrogate a clothed individual with electromagnetic radiation to determine if a concealed object is being carried. This determination includes establishing data corresponding to an image of the individual with a pair of opposed, semi-cylindrical array panels each configured to interrogate the individual with electromagnetic radiation in the 200 MHz to 1 THz range.
1. A system, comprising:
two or more arrays spaced apart from each other to define an interrogation region therebetween, the arrays each being structured to turn about the interrogation region to interrogate a person in the interrogation region with electromagnetic radiation at one or more frequencies in a range of about 200 MHz to about 1 THz to provide corresponding interrogation signals;
one or more processors operable to establish data corresponding to a topographical representation of the person determined from the interrogation signals and generate an output as a function of the data, the data corresponding to the topographical representation defining a volume of the person in the interrogation region; and
a device responsive to the output to provide an indication to an operator if the person is suspected of carrying one or more concealed objects that pose a threat to security,
wherein the one or more processors are operable to generate the data corresponding to the topographical representation of the person by combining image data sets of three-dimensional data.
2. The system of claim 1 , wherein the arrays are each provided with a panel and a mechanism to move a corresponding one of the arrays along a curvilinear path about the interrogation region.
3. The system of claim 2 , wherein the curvilinear path approximates an arc of a circle.
4. The system of claim 2 , wherein the panel for each of the arrays is at least partially transparent to facilitate viewing therethrough by an operator.
5. The system of claim 1 , wherein the device includes a display and the one or more processors include means for generating the output in a form representative of one or more cross sectional views of the person.
6. The system of claim 1 , wherein the arrays are each structured to operate at several different frequencies and each correspond to an arc about the interrogation region subtending an angle of at least 120 degrees.
7. The system of claim 1 , wherein the arrays are each structured to provide a semi-cylindrical scan.
8. The method of claim 1 , wherein the combining comprises incoherently combining the multiple image data sets.
9. The method of claim 1 , wherein the combining comprises combining the multiple image data sets using an averaging technique.
10. The method of claim 1 , wherein the combining comprises combining the multiple image data sets using a weighting function.
11. The system of claim 1 , wherein the one or more processors are further operable to render one or more two-dimensional images from the volumetric data.
12. The system of claim 11 , wherein the one or more processors are operable to perform the rendering using a ray projection technique.
13. A method, comprising:
providing two or more arrays each shaped to turn about a person positioned between the arrays;
operating the arrays to perform an interrogation of the person with electromagnetic radiation at one or more frequencies in a range of about 200 MHz to about 1 THz;
generating a plurality of image data sets from the interrogation, each of the image data sets comprising three-dimensional data; and
generating volumetric data by combining the plurality of image data sets, the volumetric data being indicative of the surface of the person.
14. The method of claim 13 , which includes moving each of the arrays along a path positioned about the person.
15. The method of claim 14 , wherein at least a portion of the path is curvilinear and the path subtends an angle of at least 120 degrees relative to the person.
16. The method of claim 14 , wherein at least a portion of the path is rectilinear.
17. The method of claim 13 , which includes displaying one or more cross sectional views of the person based on the volumetric data.
18. The method of claim 13 , wherein the generating of the volumetric data includes combining the image data sets incoherently.
19. The method of claim 13 , wherein the arrays oppose one another to define an interrogation region therebetween and are arranged to provide a security checkpoint.
20. The method of claim 13 , wherein the combining comprises combining the image data sets using an averaging technique.
21. The method of claim 13 , wherein the combining comprises combining the image data sets using a weighting function.
22. The method of claim 13 , wherein the volumetric data is further indicative of the surface of a man-made object concealed or carried by the person.
23. A method, comprising:
generating electromagnetic radiation at one or more frequencies in a range of about 200 MHz to about 1 THz with two or more arrays to perform an interrogation of a person positioned between the two or more arrays;
moving at least one of the arrays along a path about the person during the interrogation; and
generating volumetric data from the interrogation to detect if the person is concealing an object, the act of generating the volumetric data including combining a plurality of cylindrical image data sets, each of the cylindrical image data sets comprising data that is representative of a three-dimensional surface of a portion of the person.
24. The method of claim 23 , wherein the path subtends an angle of at least 90 degrees relative to the person.
25. The method of claim 23 , wherein the path subtends an angle of at least 120 degrees relative to the person.
26. The method of claim 23 , wherein the arrays number two and oppose one another to define an interrogation region therebetween and are arranged to provide a security checkpoint, and at least a portion of the path is curvilinear or rectilinear.
27. The method of claim 23 , which includes displaying one or more cross sectional views of the person based on the volumetric data.
28. The method of claim 23 , wherein the generating the combining comprises combining a plurality of image data sets incoherently.
29. The method of claim 23 , wherein the generating the volumetric data includes combining a plurality of image data sets using an averaging technique.
30. The method of claim 23 , wherein the combining comprises combining a plurality of image data sets using a weighting function.
31. The method of claim 23 , wherein the volumetric data is indicative of the surface of the person and a man-made object concealed or carried by the person.
32. The method of claim 23 , further comprising rendering one or more two-dimensional images from the volumetric data.
33. The method of claim 32 , wherein the rendering is performed using a ray projection technique.
34. The method of claim 32 , wherein the rendering comprises:
rendering a first two-dimensional image from a first viewing angle; and
rendering a second two-dimensional image from a second viewing angle different than the first viewing angle.