Vivaldi antenna realizing low return loss and high gain at low frequency

The invention discloses a Vivaldi antenna realizing low return loss and high gain at low frequency. The Vivaldi antenna is characterized in that an exponential gradient slot is loaded on the outer side of the CAVA. An EGSA antenna comprises a dielectric substrate, metal radiation sheets, a microstrip balun, an elliptical slot line and the exponential gradient slot. The metal radiation sheet are respectively fixed on the top surface and the bottom surface of the dielectric substrate. The impedance matching microstrip balun is composed of a linear gradient microstrip line and a metal patch withan elliptical slot line. The exponential gradient slot structure (EGS) is loaded on the outer side of the metal radiation sheets, the operating bandwidth of the EGSA at S < -10dB is increased to 185% of that of CAVA and the EGS structure effectively improves the return loss in low frequency band. 本发明公开一种在低频处实现低回波损耗、高增益的Vivaldi天线，其特征在于，在CAVA外侧加载指数渐变槽，EGSA天线，包括介质基板、金属辐射片、微带巴伦、椭圆槽线和指数渐变槽，金属辐射片分别固定在介质基板顶面与底面，阻抗匹配微带巴伦由线性渐变微带线与