  The quantum mechanical harmonic oscillator Hamiltonian generates a
one-parameter unitary group W(\theta) in L^2(R) which rotates the
time-frequency plane. In particular, W(\pi/2) is the Fourier transform. When
W(\theta) is applied to any frame of Gabor wavelets, the result is another such
frame with identical frame bounds. Thus each Gabor frame gives rise to a
one-parameter family of frames, which we call a deformation of the original.
For example, beginning with the usual tight frame F of Gabor wavelets generated
by a compactly supported window g(t) and parameterized by a regular lattice in
the time-frequency plane, one obtains a family of frames F_\theta generated by
the non-compactly supported windows g_\theta=W(theta)g, parameterized by
rotated versions of the original lattice. This gives a method for constructing
tight frames of Gabor wavelets for which neither the window nor its Fourier
transform have compact support. When \theta=\pi/2, we obtain the well-known
Gabor frame generated by a window with compactly supported Fourier transform.
The family F_\theta therefore interpolates these two familiar examples.
