Abstract:
:Focused impedance measurements (FIM) are used in several fields, and address the problem of measuring the volume impedance of an object within a volume conductor. Several electrode configurations are possible, and these have different properties. Sensitivity fields of four configurations have been investigated. We present one new development of an existing FIM configuration, and we made finite element models of the configurations to analyse and compare them both graphically and numerically. The models developed have a variable-sized mesh that allows us to build complex models that fit easily in computer memory. We found that one configuration in particular, FIM4, was superior to the others in most aspects. We also analysed the effects of very high sensitivities in and under the electrodes. We found that even if the sensitivity is very high under the electrodes, the effects of inhomogeneities were not as high as one might expect.
journal_name
Physiol Measjournal_title
Physiological measurementauthors
Pettersen FJ,Ferdous H,Kalvøy H,Martinsen ØG,Høgetveit JOdoi
10.1088/0967-3334/35/6/1067subject
Has Abstractpub_date
2014-06-01 00:00:00pages
1067-82issue
6eissn
0967-3334issn
1361-6579journal_volume
35pub_type
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