A Specific Data Acquisition Scheme for Electrical Tomography

Electrical tomography techniques have been developed for monitoring the internal behavior of industrial processes. The electrical tomography offers some advantages over other tomography modalities, such as low cost, no radiation and being non-intrusive. In the past, individual data acquisition systems have been used for tomographic measurement, e.g., for ECT, ERT and EMT, most of which are in analog hardware. Generally, it is difficult to transfer these systems to other modalities. This paper presents a FPGA based data acquisition scheme, which can be used to facilitate the hardware design of electrical tomography. Improvements in system performance are achieved by implementing most functions in digital rather than analog hardware. Currently, individual ECT and ERT data acquisition systems have been used for achieving dual-modality tomography, which will result in poor hardware integration and data combination. With this scheme, multi-modality measurement techniques could be integrated into a system based on a single FPGA chip, providing effective integration. Preliminary results show that the signal to noise ratio is greater than 74 dB.