Low sidelobe silicon optical phased array with Chebyshev amplitude distribution

We propose and demonstrate a silicon photonic optical phased array (OPA) with ultra-low sidelobe level. The arbitrary ratio power splitters (ARPSs) are introduced to manipulate the amplitude distribution between different channels and suppress the sidelobe level. A 32-channel OPA has been designed and demonstrated with the amplitude distribution determined by preferred Chebyshev method. The experimental results indicate that the sidelobe suppression ratio (SLSR) can be up to 25.3 dB. The measured field of view (FOV) is 84 degrees x 13 degrees with divergence of 2.8 degrees x 1.7 degrees. Furthermore, the frequency-modulated continuous-wave (FMCW) based ranging has been also demonstrated experimentally by utilizing the OPA as the transmitter.