Partial tracking optical heterodyne reciever arrays

The average antenna gain for an array of optical heterodyne receivers operating in the turbulent atmosphere is presented for the following three configurations: (1) no active tracking of the received signal wave front, (2) active tracking of the total wave front tilt across the entire array, and (3) active tracking of the wave front tilt across each element of the array. In addition, the performance of a single element from an array in the second configuration is used to show explicitly the dependence of optical resolution and of the atmospheric modulation-transfer function on exposure time.