  Interaction of a solitary wave with a long background wave is studied within
the framework of rotation modified Benjamin-Ono equation describing internal
waves in a deep fluid. With the help of asymptotic method, we find stationary
and nonstationary solutions for a Benjamin-Ono soliton trapped within a long
sinusoidal wave. We show that the radiation losses experienced by a soliton and
caused by the Earth rotation can be compensated by the energy pumping from the
background wave. However, the back influence of the soliton on the background
wave eventually leads to the destruction of the coherent structure and energy
dispersion in a quasi-random wave field.
