Compact wideband circularly polarized horn antenna with tapered slot-coupled feeding for Ku-band applications

A compact wideband circularly polarized (CP) horn antenna with slot-coupled feeding structure at Ku band for satellite communication is devised. The proposed design is based on a square aperture horn antenna with two orthogonal ridges, which is fed by nonuniform curved slot along the diagonal of the horn on the bottom cavity. And in order to improve the impedance matching, a staircase typed ridge is connected the feeding probe as a matching network. Moreover, two orthogonal ridges are excited with a tapered slot coupled by the staircase ridges via feeding probe. Wideband CP performance is achieved with an overall physical dimension of 9 mm x 9 mm x 14 mm (0.045 lambda(0) x 0.045 lambda(0) x 0.07 lambda(0) at frequency of 15 GHz). It is experimentally demonstrated that the proposed antenna achieves: a wide 10-dB return loss bandwidth of about 2.4 GHz, a 3-dB axial ratio bandwidth of 1 GHz, and a peak gain of 6.5 dBi.