Subspace approaches have become popular in the last two decades for retriev
ing constant amplitude harmonies observed in white additive noise because t
hey may exhibit superior resolution over the FFT-based methods, especially
with short data records and closely spaced harmonies. We demonstrate here t
hat MUSIC and ESPRIT methods can also be applied when the harmonics are cor
rupted by white or wideband multiplicative noise. The application context i
s the retrieval of texture information from high resolution and low grazing
angle radar clutter data affected by wideband colored speckle that is mode
led as complex multiplicative noise. Texture information is fundamental for
clutter cancellation and constant false alarm rate (CFAR) radar detection.
A thorough numerical analysis compares the two subspace methods and valida
tes the theoretical findings.