The active illumination of a target through a turbulent medium with a monostatic
transmitter–receiver results in a naturally occurring conjugate wave caused by
reciprocal scattering paths that experience identical phase variations. This
reciprocal path-scattering phenomenon produces an enhanced backscatter in the
retroverse direction (precisely along the boresight of the pointing telescope). A
dual aperture causes this intensity enhancement to take the form of Young’s
interference fringes. Interference fringes produced by the reciprocal path-scattering
phenomenon are temporally stable even in the presence of time-varying turbulence.
Choosing the width-to-separation ratio of the dual apertures appropriately and
utilizing orthogonal polarizations to suppress the time-varying common-path scattered
radiation allow one to achieve interferometric sensitivity in pointing accuracy
through a random medium or turbulent atmosphere. Computer simulations are compared
with laboratory experimental data. This new precision pointing and tracking technique
has potential applications in ground-to-space laser communications, laser power
beaming to satellites, and theater missile defense scenarios.
© 1996 Optical Society of America
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