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The line packing problem is concerned with the optimal packing of points in real or complex projective space so that the minimum distance between points is maximized. Until recently, all bounds on optimal line packings were known to be derivable from Delsarte's linear program. Last year, Bukh and Cox introduced a new bound for the line packing problem using completely different techniques. In this paper, we use ideas from the Bukh--Cox proof to find a new proof of the Welch bound, and then we use ideas from Delsarte's linear program to find a new proof of the Bukh--Cox bound. Hopefully, these unifying principles will lead to further refinements., Comment: 4 pages, conference: SampTA 2019

We apply the method of moments to prove a recent conjecture of Haikin, Zamir and Gavish (2017) concerning the distribution of the singular values of random subensembles of Paley equiangular tight frames. Our analysis applies more generally to real equiangular tight frames of redundancy 2, and we suspect similar ideas will eventually produce more general results for arbitrary choices of redundancy.

The primary focus is on Constant Amplitude Zero Autocorrelation sequences, or CAZAC sequences for short. We provide both an exposition and some new results relating to CAZAC sequences. We then apply them to Gabor frames and prove a condition for checking when Gabor systems generated by a CAZAC sequence are tight frames. We also construct multiple examples using this condition. Finally, we explore natural generalizations of CAZAC sequences to the torus and the real line and provide examples highlighting the differences between the generalizations. In the last section, we highlight some work done in image processing. In particular, we present results in single-pixel camera imaging and the demosaicing problem in image processing.