JOINT MOMENTS OF THE WAVE BEAM AMPLITUDE AND INVERSE POWER IN AN ABSORBING RANDOM MEDIUM WITH LENS PROPERTIES

This paper presents a derivation of a system of closed equations for j oint moments of the amplitude and inverse power of a wave beam propaga ting in a regularly inhomogeneous dissipative random medium. The radia tion transfer in the medium is characterized by nonconservation of the total radiation energy flux and by the existence of power fluctuation s. The statistics of the wave beam power fluctuations have been studie d. Information on the power statistical characteristics is applied to close the system of equations for joint moments. For task parameters w hich are not very strict (an effective radius of the wave beam should be considerably less than the outer scale of the turbulence) a system of independent equations for arbitrary joint moments has been obtained . The equations for the first two lower joint moments of the beam inte nsity and inverse power have been solved analytically. With the soluti ons obtained the effective wave beam parameters were calculated, i.e. the beam mean displacement, effective broadening and tremble variance (the beam wandering variance) for the propagation of radiation in the refractive channel of an absorbing turbulent medium. Radically new cha racteristics of the behaviour of the effective parameters in random ab sorbing and transparent media have been revealed.