“…For structured frames, many existence results and construction techniques have been demonstrated. The existence of unit-norm and ellipsoidal tight frames was considered in [9,14,19], the existence of (μ, S)-frames was shown in [10,19], and the results on the existence of equiangular tight frames has been demonstrated in [5,26,28]. These existence proofs are all constructive, but numerically efficient constructions have also been considered [12,25,29] and the frame potential introduced by Benedetto and Fickus [1] provides a robust iterative method for constructing finite unit-norm tight frames.…”