A novel isotopic mould measurement system for molten steel level, composed of a radioactive source, a nuclear detector and a signal processing unit, is presented. A γ-ray radioactive source with nonlinear activity distribution along the rod source is adopted to reduce nonlinearity of the measuring result. In order to measure the mould level more quickly and accurately, the algorithms for real-time signal processing are developed to determine the pulse count rate, filter the signal and to compensate the decay of the radioactive source automatic...
