Antennas And Near Field Focusing Millimeter Wave Imaging Studies

Terrorist activities arise from security problems by the world wide attention,security detection systems get focus at home and abroad,millimeter wave detection system in metals,plastics,ceramics,explosives detection has a unique advantage.Antenna near field focusing in military,medical applied,especially rapid development in research and safety testing.This paper is to study and imaging millimeter wave antenna near field focusing.This paper is designed to work in the frequency of 35 GHz,focal length 500 mm focus lens near field antenna.Using electromagnetic simulation software CST designed plane diameter of 300 mm,respectively,on both sides of the focal length of 150 mm and 300 mm lenses of different focal lengths;designed operating frequency is 35 GHz microstrip antenna as an antenna feed,get lens antenna by electromagnetic simulation software CST simulation in focus at 771 mm,lateral resolution of 22 mm.Secondly,the design of the operating frequency of 35 GHz in the near field of 32 × 32 focused microstrip array antenna.Research on the basic principle of near-field focusing microstrip array antenna,designed and 1 × 16,2 × 2,4 × 4,16 × 16 and 32 × 32 different sizes of different focal lengths near field focused microstrip array antenna,and Preparation of the focal length of 500 mm 32 × 32 array antenna,test results show that the antenna is in focus at 460 mm,transverse diameter of the focal spot size of 16 mm.Finally,earlier design microstrip antenna array of items of different materials were tested pair of rectangular metal bars,square piece of metal,metal cutting tools,ceramic knives,metal sheet metal pistol handgun millimeter wave signal acquisition and imaging and contrast.Fixed to the metal pistol plastic mannequins chest and millimeter wave body scan imaging has been carrying firearms millimeter wave image to verify the near field focused microstrip array antenna performance and focusing millimeter-wave imaging.