Abstract: A deformation compensation system for use with a large phased-array antenna system to electronically compensate for surface deformations occurring on the phased-array antenna which would otherwise compromise antenna performance. In one embodiment, a plurality of strain gauges are disposed on or integrally formed in structure forming the phased-array antenna. The strain gauges are placed at those locations on the antenna structure, where, through prior structural modeling and testing, it has been determined that high strains associated with the expected deformation of the phased-array antenna are expected to occur to a significant degree. The strain gauges output signals to a data acquisition system which uses a strain-to-displacement algorithm to produce displacements corresponding to the estimated, deformed shape of the phased-array antenna.