Slot-loaded SIW-fed Wide-band Yagi Antenna having End-fire / Broadside Scanning Features

In this paper, design of a wide-band SIW-fed printed Yagi antenna with frequency dependent radiation properties is reported. The proposed antenna utilizes an offset longitudinal slot on the SIW-feed structure, which excites a higher frequency antenna resonance having broadside radiation characteristics. Merging of this slot-mode with the end-fire Yagi dipole-mode in lower frequency range results in wide impedance bandwidth as well as radiation features showing gradual transition from end-fire to broadside direction with increase in frequency.