Radiation apparatus and multi-band array antenna

A multi-band array antenna, comprising:

• a reflection panel and a radiation apparatus array disposed on the reflection panel, wherein the radiation apparatus array comprises a first radiation apparatus and a second radiation apparatus that are disposed adjacent to each other, a frequency band in which the first radiation apparatus operates is higher than a frequency band in which the second radiation apparatus operates, and the second radiation apparatus comprises a radiation module, a first balun, and a second balun, wherein the first balun is connected to the second balun on one side of the radiation module;
• the radiation module comprises a first radiation unit and a second radiation unit that are arranged in a +45° polarization direction, and a third radiation unit and a fourth radiation unit that are arranged in a −45° polarization direction;
• and
• the first balun is configured to feed a first differential signal to the first radiation unit and the second radiation unit, the second balun is configured to feed a second differential signal into the third radiation unit and the fourth radiation unit, and the first balun and the second balun are disposed in a same plane;
• wherein the first balun and the second balun each comprise a feeding conductor, a first reference ground conductor, a second reference ground conductor, and a fastener, wherein the fastener is configured to fasten relative positions of the feeding conductor, the first reference ground conductor and the second reference ground conductor;
• the feeding conductor comprises a first feeding conductor segment and a second feeding conductor segment that extend in a first direction, the first feeding conductor segment and the second feeding conductor segment are arranged in parallel, a lower end of the first feeding conductor segment is a signal input end, and an upper end of the second feeding conductor segment is electrically connected to an upper end of the first feeding conductor segment;
• the first reference ground conductor is parallel to the first feeding conductor segment, a capacitive coupling effect can be generated between the first reference ground conductor and the first feeding conductor segment, a lower end of the first reference ground conductor is a reference ground connection end, and an upper end of the first reference ground conductor is a first signal output end;
• the second reference ground conductor is parallel to the second feeding conductor segment, a capacitive coupling effect can be generated between the second reference ground conductor and the second feeding conductor segment, a lower end of the second reference ground conductor is a reference ground connection end, and an upper end of the second reference ground conductor is a second signal output end;
• and
• the first signal output end and the second signal output end of the first balun are respectively electrically connected to the first radiation unit and the second radiation unit, and the first signal output end and the second signal output end of the second balun are respectively electrically connected to the third radiation unit and the fourth radiation unit.