Abstract: Scene-independent baseline signals in output value signals from radiometer or receiver channels used in millimeter wave imaging are eliminated or reduced and an improved image is composed. The scene-independent baseline signals are believed to result from a standing wave which is established between an antenna of the channel and a movable scanning element which scans radiant energy from the scene into each channel. The movable scanning element introduces changes in geometry which change the characteristics of the baseline signals depending upon the position of the movable scanning element. The baseline signals are measured by viewing a scene of uniform brightness temperature, and the baseline signal contribution is subtracted from the output value signals from each channel. The baseline compensated output signals are used to compose an image with better contrast.

Abstract: Scene-independent baseline signals in output value signals from radiometer or receiver channels used in millimeter wave imaging are eliminated or reduced and an improved image is composed. The scene-independent baseline signals are believed to result from a standing wave which is established between an antenna of the channel and a movable scanning element which scans radiant energy from the scene into each channel. The movable scanning element introduces changes in geometry which change the characteristics of the baseline signals depending upon the position of the movable scanning element. The baseline signals are measured by viewing a scene of uniform brightness temperature, and the baseline signal contribution is subtracted from the output value signals from each channel. The baseline compensated output signals are used to compose an image with better contrast.

Abstract: A millimeter wave detection and image generation system utilizing folded optics for reduced size. Means for scanning a received image over a radiation detection array, to improve resolution, is provided. Autofocusing of objects in the field of view of the millimeter wave detection and image generation system is also provided.

Abstract: Compact microwave and millimeter wave radars operating at 77 Ghz and having resolution of no less than 3.2 meters at a distance of 100 meters. The exemplary dimensions of the radars are 145 millimeters in diameter and 100 or 85 millimeters long. The antenna of the radars employs folded optic design, with the actual focal length of the radar being less than that of the lens in the antenna alone.

Abstract: A contraband detection system especially suited for detecting concealed non-metallic contraband such as ceramic or plastic weapons or illegal drugs carried by a person is disclosed. Plural sources of quasi-coherent millimeter wave radiation are disposed so as to uniformly illuminate a field of view. In the preferred embodiment, the radiation emitted by the sources is linearly polarized in a single plane such that the polarization of the radiation with respect to the plane in which linearly polarized radiation is preferentially received by the detectors can be controlled. For detection of dielectric objects, such as ceramic weapons or narcotics, these planes of polarization should be orthogonal to one another. The detector is a staring array which does not require scanning to generate an image of the entire field of view; the signal provided by each element of the detector array corresponds to the illumination reflected from objects in a single portion of the field of view.

Abstract: A contraband detection system especially suited for detecting concealed non-metallic contraband such as ceramic or plastic weapons or illegal drugs carried by a person is disclosed. Plural sources of quasi-coherent millimeter wave radiation are disposed so as to uniformly illuminate a field of view. In the preferred embodiment, the radiation emitted by the sources is linearly polarized in a single plane such that the polarization of the radiation with respect to the plane in which linearly polarized radiation is preferentially received by the detectors can be controlled. For detection of dielectric objects, such as ceramic weapons or narcotics, these planes of polarization should be orthogonal to one another. The detector is a staring array which does not require scanning to generate an image of the entire field of view; the signal provided by each element of the detector array corresponds to the illumination reflected from objects in a single portion of the field of view.