An apparatus for a planar phase array antenna is provided. The planar phase array antenna includes a planar waveguide formed by a top ground and a bottom ground with a dielectric layer between the top ground and the bottom ground, a phase array, including radiators, configured to form an electromagnetic wave front inside the planar waveguide, at least one back side reflecting structure located behind the phase array, and at least one deflecting structure, implemented in the dielectric layer, configured to deflect the electromagnetic wave front inside the planar waveguide, wherein a permittivity value of the at least one deflecting structure is not equal to a permittivity value of the dielectric layer of the planar waveguide.