The present invention provides a method and an apparatus for forming an antenna beam from an array antenna having a rear facing side, an aperture, and including a first and a second radiating element. The method comprises injecting a synchronization signal wirelessly from a common source at the rear facing side of the array antenna to provide an initial calibration of the array antenna that synchronizes phase of an output signal from the first and second radiating elements to the common source. The method further comprises compensating a change in phase of the synchronization signal at the first radiating element based on a spatial displacement to synchronize phase of a first portion of the output signal from the first radiating element to the phase of the synchronization signal at the second radiating element in response to the spatial displacement of the first radiating element after the initial calibration of the antenna array. A synchronization source may couple to the phased array antenna wirelessly, such as optically or using radio frequency based coupling. To synchronize a portion of an output signal from a plurality of radiating elements, a phase shift unit and/or a time delay unit at each radiating element may lock its phase to a synchronization signal from a common or a point source regardless of a location thereof relative to the synchronization source. In this way, a synchronization source may synchronize the phase of the phased array antenna even if one or more radiating elements may move from an original spatial location to any arbitrary position.