Skew estimator method for alignment of troposcatter antennas and synchronization of master clocks

Microprocessor-based instrumentation for optimum alignment of troposcatter antennas and simultaneous synchronization of transmitter and receiver oscillators is discussed. The instrument estimates various spectral moments of the Doppler spectrum of the received signal. When the third central moment or skew is zero, the antennas are properly aligned. Tests of this method indicate that alignment to within 1/10 beam width within a time period of 10 min or less is possible.