We propose a distributed Bragg deflector working as a low loss (<0.3 dB) ultra compact beam expander, which generates an on chip Gaussian beam that illuminates a 1D array of 112 optical antennas with a length of 1.5 mm . The device has been fabricated on a 220 nm silicon on insulator platform using a single etch process with a minimum feature size of 80 nm. We present an antenna array with a directivity of 53 dBi , a radiation efficiency of 3.8 dB and a far field spot with an angular divergence of 1.8 × 0.2