【摘要】 室内毫米波辐射成像时,目标和背景间的辐射温度对比度急剧下降,导致毫米波辐射图像质量较差,难以有效辨识目标。针对毫米波辐射成像用于室内人体隐匿违禁物品探测,建立了辐射温度传递模型,推导出目标和人体的视在温度分布及辐射温度对比度函数;同时结合典型目标的具体参数,分析了室内辐射温度对比度下降的原因;将噪声照射方法引入到室内辐射成像应用中,着重研究其对提高室内辐射温度对比度的贡献,并从辐射功率密度方面论证了噪声照射对人体的安全性。理论分析和仿真结果验证了噪声照射方法的可行性及有效性。更多还原

【Abstract】 When the Millimeter-wave (MMW) radiometric imaging is carried out indoors, the radiometric temperature contrast between the target and the background decreases sharply, which leads to degradation of MMW radiometric images and difficulty in recognizing targets. Based on the realistic problem of MMW radiometric imaging for detecting contraband concealed on personnel indoors, the radiometric temperature transfer model was put forward. At the same time, both the apparent temperature distribution and radiometric temperature contrast between target and human body were deduced. Combined with the specific parameters of some typical targets, the reason for low indoor radiometric temperature contrast was analyzed. Then, the method of noise illumination was adopted in the application of indoor radiometric imaging, and the contribution of this method to the improvement of indoor radiometric temperature contrast was emphatically investigated. Moreover, from the perspective of radiation power density, it was proved that noise illumination was safe to human body. Both the theory analysis and simulation results are presented to demonstrate the feasibility and significance of noise illumination.更多还原