An ion beam implanter includes an ion beam source for generating an ion beam moving along a beam line and a vacuum or implantation chamber wherein a workpiece is positioned to intersect the ion beam for ion implantation of a surface of the workpiece by the ion beam. The unwrapping of the phases is implemented over interconnected pixel regions proceeds initially only in regions with high signal amplitude and the regions of lower amplitudes are only successively acquired by increments. The reflected signal received through the microphone and a predetermined set of values or ranges stored in a memory coupled to the central processing unit are used as input for a program of instructions tangibly embodied in a programmable storage device executable by the central processing unit. The communication between the hosting program and the schedulers may be based on.