Core processing for calculating phase andamplitude of the detected signal was built on FPGA (Field-Programmable Gate-Array) platform. Phase shift demodulationalgorithm employs IP core provided by Xilinx FPGA. Directdigital synthesizer (DDS), multiplier, accumulator, and CORDIC(coordinate rotation digital computer) modules were used asexcitation-reference signal generator, signal multiplication,accumulation, and conversion to polar coordinate in order toconduct trigonometric operation respectively. Hardware designwas emulated on MATLAB-Xilinx System Generator to observeits performance. Phase detection range 0-114.58o and meanabsolute error 0.58o have been achieved. Data processing ratesolely at digital signal stage was approximately 100data/s suitablefor 32-channel ECVT (electrical capacitance volumetomography) system.
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