Directional short-time Fourier transform

A directionally sensitive variant of the short-time Fourier transform is introduced which sends functions on R-n to those on the parameter space Sn-1 x R x R-n. This transform, which is named directional short-time Fourier transform (DSTFT), uses functions in L-infinity(R) as window and is related to the celebrated Radon transform. We establish an orthogonality relation for the DSTFT and explore some operator-theoretic aspects of the transform, mostly in terms of proving a variant of the Hausdorff-Young inequality. The paper is concluded by some reconstruction formulas. (C) 2012 Elsevier Inc. All rights reserved.