id: 06045875 dt: j an: 06045875 au: Bajwa, Waheed U.; Calderbank, Robert; Mixon, Dustin G. ti: Two are better than one: fundamental parameters of frame coherence. so: Appl. Comput. Harmon. Anal. 33, No. 1, 58-78 (2012). py: 2012 pu: Elsevier Science (Academic Press), Orlando, FL la: EN cc: ut: frames; worst-case coherence; Welch bound; sparse signal processing ci: li: doi:10.1016/j.acha.2011.09.005 ab: This paper only considers finite-dimentional frames and investigates two parameters that measure the coherence of a frame: worst-case and average coherence. The authors use them to derive near-optimal probabilistic guarantees on both sparse signal detection and reconstruction in the presence of noise, and provide a catalog of nearly tight frames with small worst-case and average coherence. They also find a new lower bound on worst-case coherence, compare it to the Welch bound and use it to interpret recently reported signal reconstruction results. Finally, they present an algorithm that transforms frames in a way that decreases average coherence without changing the spectral norm or worst-case coherence. rv: Richard A. Zalik (Auburn)