http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
김보열(Boyeoul Kim),이재천(Jaecheon Lee) 한국자동차공학회 2009 한국자동차공학회 학술대회 및 전시회 Vol.2009 No.11
This paper suggests the practical method for designing anechoic chambers by investigating types of anechoic chambers for evaluating characteristics of antenna, shielding room, inner absorber and auxiliary facilities. The anechoic chamber for evaluating characteristics of far field antenna is designed to have a frequency bandwidth from 800 ㎒ to 18 ㎓ and quite zone of 0.5m distance. The path length was determined to be 4m by applying the equation of R?2D²/λ. The anechoic chamber is designed with a Panel Wood Enclosure; the skin depth (the width of the anechoic chamber) is determined by the equation δ=√1/πfμσ. The APM45(18 inch) absorber is applied to specular regions of both side walls, ceiling, and floor of the room where the greatest reflection occured as well as the back wall in the direction of the quite zone. The wall adjacent to the transmitting antenna is covered with APM20(8.3 inch) while all remaining surfaces are covered with APM30(12 inch). This is designed to minimize the amount of reflected energy at the quite zone. The design was validated by performing shielding tests in addition to measuring the amount of reflected energy. Through these test, it was shown that the design conforms to the industry standard for anechoic chambers.