I. Introduction
Capacitively coupled electrical resistance tomography (CCERT) was proposed as a new electrical tomography (ET) technique [1], [2]. Although the sensor structure of CCERT is similar to that of electrical capacitance tomography (ECT), CCERT is regarded as an improved contactless alternative to electrical resistance tomography (ERT) because it focuses on the imaging of conductive materials. By referring to the contactless measurement idea of the capacitively coupled contactless conductivity detection (C4D) technique [3], [4], the electrodes of CCERT are not in contact with the measured medium, so the problems of ERT resulting from contact measurement can be avoided, that is, electrode polarization, electrochemical erosion, and so on. Currently, CCERT has shown good application potential in the measurement and monitoring of the gas–liquid two-phase flow. However, although previous work has verified the feasibility and effectiveness of CCERT, there is still a gap between its imaging quality and the requirement for practical application. Therefore, further research work is needed.