An apparatus includes a waveguide of an antenna block configured to propagate electromagnetic energy along a propagation direction. The antenna block includes a port located on a bottom surface of the antenna block and an antenna array located on a top surface of the antenna block. The antenna block further includes a set of waveguides in the antenna block configured to couple the antenna array to the port. Additionally, the antenna block includes at least one surface wave radiator, where the surface wave radiator is located on the top surface of the antenna block.