根据等效介电常数为负(epsilon—negative,ENG)的超介质层加载偶极子天线可增强辐射效率的原理,提出一种新型电小天线。采用“门”型单元结构对中心频率为400MHz的电单极子加载,在提高天线辐射效率的同时极大地减小天线尺寸。测试结果表明,“门”型电小天线的增益与传统0.25λ单极子天线相当,比同尺寸单极子天线提高8dB,实际天线尺寸仅为0.08λ。
A metamaterial loaded dipole electrically small antenna is proposed based on the theory of a very short cen- ter-fed cylindrical electric dipole loaded with a spherical shell of homogenous, isotropic epsilon-negative (ENG) material to enhance its radiation efficiency. We adopt a "door" shape element to load in the electrically small monopole working on 400MHz. The radiation efficiency of the antenna is improved and the antenna dimensions is decreased greatly. The measurement results confirming the validity of the "door" type electrically small antenna show that the gain of the "door" type electrically small antenna equals to that of the 0.25λ monopole, 8dB higher than that of monopole of 60mm, and the size of the "door" type electrically small antenna is only 0.08λ.