Three Millimeter Remote Sensing Core Technology

In recent years, with the development of microwave technology, the researchabout electromagnetic wave is improving the spectrum, and millimeter wave isbecoming the research focus. Millimeter wave remote sensing is a technologywhich distinguishes the different objects without connecting with the target byreflection、 refraction and diffraction of the electromagnetic wave. Thistechnology has a lot of applications in atmosphere、geology and military. Inforeign countries, millimeter wave remote sensing technology has put into use,however, the technology doesn’t develop maturely because of the limit of themanufacture and design. Therefore, a number of experiment is needed.The project is from national major scientific instruments and equipmentdevelopment projects millimeter wave imaging instrument development andindustrial demonstration, to research the feed antenna and millimeter radiometer.The feed antenna with high gain、excellent directivity, the low noisy amplifierwith low noisy、high stability and the filter with good selectivity are designed.Simulation is taken to confirm the correction of the design.The Planck blackbody theory is the basement of the article. By this theory,the relationship of power and temperature is obtained to support the detection ofthe millimeter radiometer; the principle of different millimeter radiometers isanalyzed to choose a suited one; the temperature of the millimeter radiometer isdeduced to search method to enhance it.The parameter of the feed antenna which is used in millimeter wave remotesensing technology is introduced, and to realize the performance, Cassegrainantenna is selected; according to the principle of Cassegrain antenna, the methodof design is proposed, and the model is constructed to verify the facticity; thefeed antenna is adjusted to improve its performance, and a higher gain and lowerreturn loss is caught.The parameter of a low noisy amplifier which works at94GHz is analyzed;the theory and design is introduced, and according that, the attention of thedesign is enumerated; an adaptive HEMT which works at3GHz is designed andsimulated to test the correction of the technique. The filter which works at medium frequency in millimeter radiometer ispresented, and its theory and parameter is inferred,and the model of the filter isconstructed by ADS. Simulation is operated, and gets a excellent result; tosimulate the real environment, a landspace simulation is practiced which will laythe foundation for future practical processing.