| In this paper, the sensitivity calculation of electromagnetic tomography system,EMT sensors optimization and the design of new type sensor were completed basedon MATLAB programming software. All the research belongs to the category ofelectromagnetic tomography forward studies.Electromagnetic tomography system is a new type of electronic imagingtechnology. The electromagnetic sensors distribute in the measured region boundaryfor motivation and induction of the electrical signal. The media distributioninformation of the field was extracted by―cycle motivation and detection "modelfrom the different angle projections. Distribution image was reconstructed by theimaging algorithm. Insides, forward study of EMT is the bridge connected theelectrical signal performance and medium distribution.In this paper, the main work and innovation points embodied in the followingfour aspects:1. Theoretical work, the sensitivity of electrical tomography systems wasgiven. A new method to compute the sensitivity called field extractionmethod was raised innovatively. Detailed derivation process and unifiedexpression of sensitivity calculation were shown. Compared with thetraditional experiment perturbation method and the simulation perturbationmethod, Field extraction method is faster, matrix dimension and pixelpoints are easy to control, calculation model is more close to the specificapplication environment of electromagnetic sensor.2. Programming calculation. Based on the MATLAB software, theconductivity sensitivity matrix and permeability sensitivity matrix ofelectromagnetic tomography system with8coils were calculated.Sensitivity calculation flow chart, modular design, details design,4kindsof typical graphical sensitivity calculations, the final results analysis of thesensor sensitivity matrix characteristic with high accuracy were shown inthis part.3. Sensor optimization. Based on the sensitivity eigenvalue analysis, theSensing characteristics of electromagnetic tomography system with16 coils an32coils were compared under the three different imaging accuracyrequirements. The guidance theory about Electromagnetic tomographysystem sensor number optimization was raised up.4. New sensor design. Through the novel design of spiral structure, theintensity and uniformity of the magnetic flux distribution greatly increased.the shortcomings of Uneven sensitivity distribution and low sensitivityvalue were changed radically. Sensing characteristics of electromagneticsensor detection system greatly improved. |
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