9. Data Acquisition System Figure 2 : The practical data acquisition system of scintillation detector Signals. (1) Scope , (2) high voltage source, (3) scintillator , (4) power supply
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12. FPGA Design Flow of the solution Timing Analysis - Verify Performance Specifications Were Met - Static Timing Analysis Gate Level Simulation - Timing Simulation - Verify Design Will Work in Target Technology Program & Test - Program & Test Device on Board t clk
13. Pre-processing Phase 1-Wavelet based Decomposition 2- Interpolation based Reconstruction Pulse Shaping & Counting Multichannel analyzer Store & Show data Figure 3: The overall proposed solution
14. Pre Amplifier Main Amplifier SCA MCA Counter A B Figure 4: The proposed solution
15. Hardware System Figure 5: The FPGA XSC50k-Spartan II and the PC-based parallel interface
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17. Effect of Noise on Pulse Shaping & Counting Figure 6: Effect of noise on pulse shaping
25. Statistics of Four Decomposition Levels Table 1: Statistics of four levels Haar transform CC ED MSE PSNR Level 0.9681 20.4778 0.1693 27.8567 One 0.9830 14.7395 0.1575 30.7084 Two 0.9866 12.7990 0.1443 31.9258 Three 0.7021 57.0625 3.2561 18.9554 Four
26. Table 2 : Similarity measure of constructed and original signals of the different mother wavelets Comparison of Different Mother Wavelets CC ED MSE PSNR Mother Wavelet 0.9866 12.7990 0.1643 31.926 Haar 0.9890 11.8139 0.1418 32.5656 Daubechies 0.9900 11.3834 0.1324 32.8635 Coiflet 0.0148 106.878 11.4230 13.5046 Meyer 0.9886 12.2776 0.1533 32.227 Biorthogonal
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28. Reconstruct Signals Using Interpolation Figure 10: a) Original signals. b) Transformed signal. c) Reconstructed signals
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30. Table 3: Statistics of different interpolation techniques Comparison of Applying Different Interpolation Techniques CC ED MSE PSNR Method 0.9782 16.4669 0.2731 29.7192 Linear 0.9866 12.7990 0.1643 31.9258 Cubic Spline 0.9307 28.8462 0.8380 27.8501 Nearst 0.9818 14.8984 0.2226 30.6066 Cubic Hermit
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32. Accumulation Technique Figure 11: Digital processing algorithm of scintillation detector signals
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34. Comparison of the Preprocessing Results Table 4: Statistics of the preprocessing techniques CC ED MSE PSNR Method 0.9680 21.3433 0.4555 27.4972 Accumulation Tech 0.9831 14.7856 0.2186 30.6856 Median filter 0.9866 12.7990 0.1643 31.9258 Proposed Solution.
A scintillator is a material that converts energy lost by ionizing radiation into pulses of light
The compression performance is the basis for the choice of these wavelets among the different wavelet families in terms of PSNR. Signals in this case are the scintillation detector signals, and the noise is the error introduced by compression Therefore, in some cases one reconstruction may appear to be closer to the original than another, even though it has a lower PSNR (a higher PSNR would normally indicate that the reconstruction is of higher quality)
(a) Approximation coefficients at level one (b) Approximation coefficients at level two (c) Approximation coefficients at level three (d) Approximation coefficients at level four
There are a number of factors affect energy resolution, the size thickness and state of the transducer, the photon energy, and the characteristics of the electronic stage all determine the limits of energy resolution