Patent ID: 7265709

Claim:
A method of surveilling a subject, the subject including a person and any discernible objects with the person, the method comprising: transmitting toward the subject in a subject position, electromagnetic radiation in a frequency range of about 100 MHz to about 2 THz, from positions spaced from the subject position; receiving from the subject electromagnetic radiation emitted from the subject in response to the transmitted electromagnetic radiation; producing an image signal representative of the received radiation; producing from the image signal, image data corresponding to a first image of at least a portion of the subject having picture elements with different levels of intensity; determining whether the image data corresponding to the first image includes characteristics corresponding to an obiect on the person, including determining a correlation of the levels of intensity of at least one group of picture elements with the levels of intensity of a corresponding reference group of picture elements, including identifying at least a portion of the image data corresponding to which there is at least a threshold correlation of the levels of intensity of the picture elements in the at least one group of picture elements with the levels of intensity of the picture elements in the reference group of picture elements, including determining a correlation value of a given picture element that is derived from the intensity levels of a group of associated picture elements arranged relative to the given picture element, including modifying the original intensity level each picture element of the group of associated picture elements, by an amount related to the position of the picture element in the group relative to the given element, and combining the modified intensity levels; and when the image data corresponding to the first image is determined to include characteristics corresponding to an obiect, determining the location in the first image corresponding to image data including characteristics corresponding to an obiect.