| Millimeter-wave (MMW) wavelengths is at the field between infrared and microwave, so it has the same characteristics of two ranges. Passive millimeter-wave imaging has been a hot research from 90s' . Problems of current imaging systems, which relied on mechanical scanning of a single beam across the scene, are low spatial resolution and poor sensitivity. In recent years, the technology of passive millimeter-wave imaging of high spatial resolution develops very fast depending on the rapidly development of solid state components and signal processing technology. Focal plane array, multi-beam array imaging systems, which promise an increase in resolution and real-time processing, is gradually used in both the military and civilian applications.Firstly, we explain the common theory and principles of passive millimeter-wave imaging and analyze several technical indexes of the imaging system. Secondly, we got the passive MMW image by processing the experiment data and verify the possibility of the single channel scanning passive MMW imaging. The technology of focal plane arrays is introduced, and the features of data rate, multi-beam, spatial resolution and spatial sampling are analyzed in detail, and the features of two kinds receiver and three scanning methods are presented. Thirdly, this thesis focuses upon passive millimeter-wave image processing. Depending on millimeter-wave characteristics of low spatial resolution and image blurring, we discuss the nonlinear extrapolation algorithm, reformative algorithm and a super-resolution image reconstruction algorithm based on projection onto convex sets (POCS). At last we design multi-channel parallel scanning video image real-time processor based on DSP in this paper. |
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