Passive Millimeter-wave Detector Signal Acquisition, Analysis And Target Identification

In order to estimate performance parameters of a passive millimeter wave detector and investigate signal characteristic of a metal target, an experimental table, which is used to simulate detector working state, is necessary to acquire half-practicality-emulation data. The paper research is based on a passive millimeter wave detector item and sustains this item simulate experiment with essential equipments. Meanwhile, the paper analyses experimental data and investigates target signal characteristic. The detailed content is as follows.Firstly, based on heat radicalization theory, this paper analyses objective radiating brightness contrast at 8mm band and explains theoretical foundation for detecting ground metal target with a passive millimeter wave detector. The principle and output signal expression of a passive millimeter wave detector are discussed in detail.Secondly, a servo-controller circuit is developed to control the simulative experimental table which would scan at 5 rps speed, its principle and software design are presented. And measure result of servo system rotational speed is given in a convenient way.Thirdly, the principle and design method of datum sample circuit are investigated, which records the detector output voltage in real time with 14-bit A/D and 8M bytes nonvolatile SDRAM through about 30 kB/s sampling speed. Recorded data are transmitted to PC with RS-232-C bus and re-displayed with a graph software.Fourthly, it is introduced to obtain outdoor experimental data, and experimental data are investigated and processed.Finally, Detector output signals from simulative experiment are investigated systematically to acquire output signal characteristic when detector scans target based on ground-substance background. And a target distinguishing DSP circuit is given and simple target distinguishing arithmetic is discussed.