A serial data acquisition architecture for continuous impedance imaging

Q.S. Zhu, MIEEE, C.N. McLeod, C.W. Denyer, F.J. Lidgey, MIEEE and W.R.B. Lionheart EIT Reseaxh Group School of Engineering, Oxford Brookes University, Oxford, OX3 OBP, UK. Abstract A serial data acquisition system architecture and its specifications for continuous impedance imaging are presented. The new system design avoids com lexity and high cast associated with the pade l approach which is normdy taken to obtain high speed in muhi-channel measurements. The scheme involves applications of a video speed A D C device and multiplexers, configured IO scan through a l l the channels simultaneously. Non-uniform over-sampling technique is implemented through precision control of digirishg thing. With the system architectuE. the multiple drive system is capable of achieving 16-bit data acquisition accuracy at a speed of 25 frames per second image production.

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