More New Structural Properties of Costas Arrays

We present new structural properties about Costas arrays. Building on our 2018 RadarConf paper, we provide new conjectures and results pertaining to the differences of the elements of a Costas array when written as a permutation in one-line form. Our findings characterize forbidden frequency modulations within the frequency hopping waveform prescribed by a Costas array and could help to expedite exhaustive enumeration of Costas arrays.