The invention relates to a feedforward
radar antenna. The antenna comprises a feed source and a
metamaterial panel. The antenna also comprises a reflecting plate clinging to one side of the
metamaterial panel, wherein the
metamaterial panel comprises a plurality of core
layers with the same
refractive index distribution; each core layer comprises a plurality of metamaterial units; each metamaterial unit comprises a unit substrate with one or more holes; the refractive indexes of the core
layers of the metamaterial panel are circularly distributed, with own centers as the centers of circles; the
refractive index gradually decreases with increase of the
radius; and the refractive indexes in positions with the same
radius are the same. The feedforward
radar antenna has the following beneficial effects: by designing the
distribution law of the refractive indexes inside the metamaterial panel, the deflection of large-angle incidence of electromagnetic
waves is improved, and the energy
radiation efficiency is improved; meanwhile, the front-to-back ratio of the antenna is increased, and the
directivity of the antenna becomes better; and as the antenna adopts the flat metamaterial, the space of the antenna is saved.