Millimetre Wave Camera

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DESCRIPTION: A microwave and millimetre wave one-shot imaging system or camera for rapid imaging of an object using an array of modulated slot antennas is disclosed. The array measures the electric field scattered by the object at a sufficient number of discrete locations corresponding to a certain spatial domain (e.g., a portion of plane be it planar, cylindrical, spherical, or arbitrarily shaped) located away from the object. The use of the slots modulated by active elements such as diodes (e.g., PIN diodes) or by other means and their arrangement provides for high measurement sensitivity and spatial resolution associated with the array elements at higher frequencies. The array is subsequently integrated with other system components including the RF transmitter and receiver circuits, processor, and display. Using special processing of the measurements at the discrete locations, 2D or 3D images of the object's spatial and/or dielectric profiles can be generated (e.g., holographical images). The slot antennas incorporated into the array may take various designs (e.g., sub-resonant slots, resonant slots) depending on the application. The array may can measure electric field at different polarizations that may increase the amount of geometrical and materials information revealed about the imaged object. The array may be slightly displaced in two orthogonal directions to increase the number of samples obtained per wavelength resulting in increased spatial resolution of the system. For instance, the displacement can be just a quarter-wavelength. When built with linearly polarized modulated slots, the electric field in the orthogonal direction can be still measured by rotating the array 90 degrees.