P2D-5 The Progressive Dynamic Focusing Correction Technique in NDE

The progressive dynamic focusing correction technique (PROFOC) has been recently proposed as an efficient methodology to beamformer implementation. A single bit per focus allows determining the sampling instant at every array channel with high timing resolution to get wide dynamic range images. However, this requires a separate sampling clock generator for every array element, while most state of the art multi-channel A/D converters share a common clock signal. This work proposes a method to use the PROFOC technique with these devices. On the other hand, the performance of the new technique in NDE applications is assessed. The evaluation is carried out using static and PROFOC dynamic focusing, with foci at regular or dynamically varying intervals.