The invention discloses a high-speed feed circuit for realizing low-reflection transmission of an
intermediate frequency signal in a
broadband, relates to the technical field of direct modulation and sub-terahertz-terahertz communication, and solves the problems of large reflection, poor
signal integrity and narrow
intermediate frequency bandwidth of an existing feed circuit. The antenna comprises a first coaxial connector, a first transition structure and a
microstrip line, the first coaxial connector comprises a first
coaxial probe extending towards the
microstrip line, the first transition structure comprises a
dielectric substrate, back
metal and a first
metal groove, one end of the
dielectric substrate is connected with the first coaxial connector, and the other end of the
dielectric substrate is connected with the second coaxial connector. The
microstrip line is arranged on the upper surface of the
dielectric substrate, one end of the microstrip line is connected with the first
coaxial probe, the lower surface of the
dielectric substrate is covered with the back
metal, the first metal groove is formed in the face, away from the
dielectric substrate, of the back metal, and the position of the first metal groove corresponds to the position of the first
coaxial probe. The structure is simple and symmetrical, and intermediate-frequency
signal low-reflection transmission can be realized in a
broadband.