What image resolution can be achieved using ECT?
The resolution of an ECT permittivity image is limited by the number of independent measurements that can be made and this relationship can be considered to be an example of spatial filtering, as shown in the figure below. The resolution limit is difficult to define mathematically, but a simple engineering estimate can be made by assuming that the number of independent measurements M corresponds to a similar number of discrete regions inside the sensor. If we assume that the angular resolution is equal to the number of electrodes E, then the radial resolution will equal M/E. For protocol 1 and a 12 electrode sensor, this gives a radial resolution limit of 5.5. For protocol 2 and 24 electrodes, this figure increases to 10.5.
