A free-space adaptive optical laser communication system having signal
transmission and reception channels at all terminals in the communication
system, wherein wavefront sensing (WFS) and wavefront correction
mechanisms are employed along signal transmission and reception channels
of all terminals in the communication system (i.e. adaptive optics) to
improve the condition of the laser beam at the receiver (i.e. reduce the
size of the spot a the detector plane). in the illustrative embodiment,
the WFS mechanisms employ a novel WFS control process, in which active
updating of reference positions and subaperture locations on the
wavefront sensor. These WFS mechanism can be used in diverse application
environments, including but not limited to FSO laser communication
systems.