Anac-basedelectricalcapacitancetomographyECTsystemhasbeendevelopedatUMIST,withsinusoidalexcitationandphase-sensitivedemodulationPSD.Inthisarticletheoverallsystemdesignisbrieflydescribedandthendiscussedindetailarethekeydesignfeatures,neededtoachieveahighsignal-to-noiseratioandahighdat