Planar antenna for directive beam steering at end-fire using an array of surface-wave launchers

A planar surface-wave antenna (SWA) that achieves radiation at end-fire by surface-wave (SW) excitation is presented for millimetre-wave frequencies of operation. The 2D SWA is fed by a two-element array of printed SW launchers for controlled beam steering in the far-field. Measured results demonstrate a highly directive beam pattern with a 3 dB beamwidth less than 5° at 22.71 GHz. Such a planar low-cost and low-profile SWA design may be advantageous for surveillance systems and radar applications where beam steering at end-fire is of interest.