In this Supplement, we provide complementary results to the main manuscript. The first section is dedicated to a detailed mathematical description of the photonic correlator. In the second one, we investigate the different effects that affect the shape of the RF comb, and ultimately limit the performance of the correlator. Then, we provide experimental evidence of the correlation of dynamic signals, i.e. signals whose spectrum varies with time. Finally, we report additional results on the correlation of pseudo-random binary sequences.