We present a group-theoretical derivation of the continuous wavelet transform (CWT) on the 2-sphere S2, based on the construction of coherent states associated to square integrable group representations. The parameter space X is the product of SO(3) × R*+, embedded into the Lorentz group SOo(3,1) via the Iwasawa decomposition, and X -SOo(3,1)/. The space L2(S2,d) carries a unitary irreducible representation of SOo(3,1), which is square integrable over X, and thus yields the wavelets on S2 and the associated CWT.
Corentin Jean Dominique Fivet, Nicolas Robin Montagne, Olivier Baverel