  Noncommutative phase space of an arbitrary dimension is considered. The both
of operators coordinates and momenta in noncommutative phase space may be
noncommutative. In this paper, we introduce momentum-momentum noncommutativity
in addition to coordinate-coordinate noncommutativity. We find an exact form
for the linear coordinate transformation which relates a noncommutative phase
space to the corresponding ordinary one. As an example, the Hamiltonian of a
three-dimensional harmonic oscillator is examined.
