Affiliation:
1. University of California Los Angeles
Abstract
We analyze here a candidate system for correcting the wander of a
self-channeled laser pulse using a fast-steering mirror along with a
cooperative beacon imaged with a telescope. For our model system, the
imaging telescope is coaxial with the propagation of the outgoing
pulse. In the ideal case, any incoming light gathered from the beacon
would be collimated, such that taking a centroid beacon image would
yield the precise tip and tilt required for the self-channeled pulse
to propagate back to the beacon on the reciprocal path. The degree to
which reality differs from this ideal case determines the
effectiveness of the wander correction. We simulate our system for a
range of propagation and imaging conditions. We also show that in the
absence of image noise (i.e., when the beacon power is arbitrarily
high, and the signal-to-noise ratio is not an important
consideration), the system exhibits its best performance when the
receiving aperture diameter of the imaging system is close to the
transverse size of the outgoing pulse, maximizing reciprocity. When
realistic noise and finite beacon power are included in the
simulation, however, we find that this reciprocity advantage may not
be sufficient to compensate for the reduced photon count and resolving
power of a small receiving aperture. In this case, the optimal
aperture diameter will be the smallest possible, which allows for an
acceptable signal-to-noise ratio.
Subject
Atomic and Molecular Physics, and Optics,Engineering (miscellaneous),Electrical and Electronic Engineering