Microwave imaging employs detection techniques to evaluate hidden or embedded objects in a structure or media using electromagnetic (EM) waves in the microwave range, 300 MHz-300 GHz. Microwave imaging is often associated with radar detection such as target location and tracking, weather-pattern recognition, and underground surveillance, which are far-field applications. In recent years, due to microwaves' ability to penetrate optically opaque media, shortrange applications, including medical imaging, nondestructive testing (NDT) and quality evaluation, through-the-wall imaging, and security screening, have been developed. Microwave near-field imaging most often occurs when detecting the profile of an object within the short range (when the distance from the sensor to the object is less than one wavelength to several wavelengths) and depends on the electrical size of the antenna(s) and target.

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微波近场成像的进展：原型、系统和应用

微波成像采用检测技术，使用 300 MHz-300 GHz 微波范围内的电磁 (EM) 波来评估结构或介质中隐藏或嵌入的物体。微波成像通常与雷达检测相关，例如目标定位和跟踪、天气模式识别和地下监视，这些都是远场应用。近年来，由于微波具有穿透光学不透明介质的能力，包括医学成像、无损检测（NDT）和质量评估、穿墙成像和安全检查在内的短距离应用得到了发展。微波近场成像最常发生在短距离内检测物体的轮廓时（当传感器到物体的距离小于一个波长到几个波长时），并且取决于天线的电气尺寸和目标。