Design of beamforming slot antenna arrays using substrate integrated waveguide

In this work, a 77 GHz antenna is proposed which provides beam scanning over a range of 40 degrees. Two different substrate integrated waveguides (SIW) feed resonant slot sub-arrays in the above layer from either side. Arbitrary beam angles can be set by altering the width of the feeding SIW appropriately. The proposed solution can be used as a monopulse antenna in radar applications. Matching and phase equalizing are achieved by means of inductive posts. The isolation is kept above 15 dB, while directivity equals 15-16 dBi over the designed beam span.