Ku-band broadband wide-beam circularly polarized microstrip antenna

The invention provides a broadband wide-beam circularly polarized microstrip antenna applied to a Ku wave band. The antenna comprises two layers of patches, a substrate integrated waveguide, a feed blind hole and a floor. The patch is a rectangular patch loaded with branches, a U-shaped groove is formed in the middle of the patch, the resonant frequency of the upper patch is high, the resonant frequency of the lower patch is low, and the upper patch and the lower patch are combined to achieve large bandwidth. The substrate integrated waveguide is composed of a top layer L-shaped patch and metal through holes and is distributed around the patch, and the beam width of the antenna is widened through the guiding effect on a patch radiation field. The feed blind hole feeds the excitation patch, and the floor is arranged at the bottom layer of the antenna. The invention has the advantages of small size and easy conformality. And wide-beam and low-axial-ratio circularly polarized waves can be radiated in a wide freq