2000/01/31 by Ola Bratteli, Palle E. T. Jorgensen
Mathematics · #math.FA #msc:46L60 #msc:47D25 #msc:42A16 #msc:43A65 #msc:46L45 #msc:42A65 #msc:41A15
published as Wavelet Analysis and Applications (Guangzhou, China, 1999) (Donggao Deng, Daren Huang, Rong-Qing Jia, Wei Lin, and Jianzhong Wang, eds., catalogued under Deng alone), AMS/IP Studies in Advanced Mathematics, vol. 25, American Mathematical Society, Providence, International Press, 2002, pp. 35--65 · AMS-LaTeX; 30 pages, 2 tables, 1 picture. Invited lecture by Jorgensen at International Conference on Wavelet Analysis and Its Applications, Zhongshan University, Guangzhou, China, in November 1999. Changes: Some references have been added and some technical points in several proofs have been clarified in this new revised version
In this paper, we study wavelet filters and their dependence on two numbers, the scale N and the genus g. We show that the wavelet filters, in the quadrature mirror case, have a harmonic analysis which is based on representations of the C^*-algebra ON. A main tool in our analysis is the infinite-dimensional group of all maps T -> U(N) (where U(N) is the group of all unitary N-by-N matrices), and we study the extension problem from low-pass filter to multiresolution filter using this group.