ABSTRACT: This paper proposes the use of shift-invariant dual-tree discrete
wavelet transform (DT DWT) noise model to the problem of a
multipath signal detection in underwater environment. The design
procedure for this adaptive model of the background noise is described.
When an input signal is shifted, as in a multipath environment, this
shift-invariant DT DWT can generate multi-resolution subspaces.
Each of them keeps more coefficient energy of this signal than
DWT’s. The result of computer simulations shows that this method
can improve the performance of a multipath signal detection, by
reducing the false alarm probability in a range of different signal-tonoise