University of South Wales DSpace >
University of South Wales >
Advanced Technology >
Engineering and Technology >
Please use this identifier to cite or link to this item:
|Title: ||A comparison of sensors for minimizing the primary signal in planar-array magnetic induction tomography|
|Authors: ||Watson, S.|
Igney, C. H.
Williams, R. J.
|Keywords: ||magnetic induction tomography|
electrical impedance tomography
|Issue Date: ||3-Feb-2004|
|Publisher: ||IOP Publishing|
|Citation: ||Watson, S.; Igney, C. H.; Dössel, O.; Williams; R. J. and Griffiths, H. (2005) 'A comparison of sensors for minimizing the primary signal in planar-array magnetic induction tomography.' Physiological Measurement, 26(2), pp: 271-279.|
|Abstract: ||In biomedical magnetic induction tomography (MIT), measurement precision may be improved by incorporating some form of primary field compensation/cancellation scheme. Schemes which have been described previously include gradiometric approaches and the use of 'back-off' coils. In each of these methods, however, the primary field cancellation was achieved only for a single transmitter/receiver combination. For the purpose of imaging, it would be desirable for a fully electronically scanned MIT system to provide a complete set of measurements, all with the primary field cancelled. A single channel suitable for incorporation into an MIT system with planar-array geometry is described. The transmitter is a 6-turn coil of wire 5 cm in diameter. The receiver is a surface mount inductor, of inductance 10 µH, mounted such that, in principle, no net primary field flux threads it. The results of measurements carried out with the single channel system suggest that the signal due to the primary excitation field can be reduced on average by a factor of 298 by the sensor geometry over the operating frequency range 1–10 MHz. The standard deviation and drift of the signal with the system adjusted for maximum primary field cancellation, expressed as a percentage of the signal when the receiver coil was rotated until its axis of sensitivity lay along the primary field, were 0.0009% and 0.009%, respectively. The filter time constant used was 30 ms.|
|Appears in Collections:||Engineering and Technology|
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.