海雾对3毫米波传播特性的影响研究

进行了海雾对3mm传播特性影响的测量实验．浓度大的海雾对3mm信号衰减达7．55dB／km，推算了海雾的特性参数，对不同能见度下的测量结果和用ITU模式计算的结果进行了比较，并对信号闪烁特性进行了分析．

SEA FOG EFFECTS ON RADIOWAVE PROPAGATION AT 3mm WAVELENGTH

The experiments on 3mm radiowave propagatin attenuation induced by sea fog were carried out. The results show that dense fog induces 7.55dB/km attenuation at 3mm. The sea fog characteristic parameters were calculated. The measured attenuation was compared with that calculated by ITU model at different visibility. Signal scintillation characteristics were analyzed. Key words 3mm communication, attenuation, visibility, scintillation index.um 11211$$$$ YANG Cheng yongSchool of Life Sciences,Zhongshan University,Guangzhou 510275,China,ZHOU Shi ning,ZHOU Yi pin,LIN Yong cheng Abstract:Bacterium 11211 which produces chitinase was isolated from the South China Sea.The growth condition and chitinase production of bacteria were investigated.Na was necessary for bacterium 11211 growth.Colloid chiyin could induce bacteria to produce chitinase.The growth of bacteria was slow in the medium containing colloid chitin as main carbon source,and the enzyme activity reached maximum on 7 d of incubation.Following the purification,the enzyme was characterized and its molecular weight was estimated by SDS PAGE.