Showing papers on "Phase conjugation published in 1974"

Shared pointing for offset target of an adaptive phased array

Abstract: A coherent optical adaptive system employs phase conjugation for locking the beam of a phased array of laser transmitter to a target, focusing the beam on the target and compensating for distortion and disturbances both within the system and in the propagating medium between the system and the target. A first diffraction-limited lobe of the beam is locked on a real target to track the real target. Simultaneously a second diffraction-limited lobe is directed to a location having a predetermined offset with respect to the target and relative energy of the two lobes is selectively adjusted. A signal component representing a fictitious target that is offset by a predetermined amount from the real target is summed with the signal received from the real target, the phase of the sum is compared with the phase of a reference, and the phase of the transmitted signal is adjusted so as to null the difference between the sum and the reference phases for each of a number of channels.