Title |
Noise Reduction Algorithm For The Detection of Fine Ion Signals in Residual Gas Analyzer |
Authors |
허경용(Gyeongyong Heo) ; 최훈(Hun Choi) |
DOI |
http://doi.org/10.5370/KIEE.2019.68.1.102 |
Keywords |
Residual gas analyzer ; Noise reduction ; Mass spectrum ; Curve fitting ; Linear fitting ; Peak position error |
Abstract |
This paper proposes a method to improve the mass spectral detection performance of the residual gas analyzer. By improving the mode estimation method for setting the threshold value and improving the additive noise elimination method, it is possible to detect mass spectrums having low peak values of the threshold level difficult to distinguish from noise. Ion signal blocks for each mass index with noise removed by the improved method are effective for eliminating invalid ion signals based on the linear and quadratic fittings. The mass spectrum can be obtained from the quadratic fitted curves for the reconstructed ion signal block using only the valid ion signals. In addition, the resolution of the mass spectrum can be improved by correcting the error caused by the shift of the spectral peak position. To verify the performance of the proposed method, computer simulations were performed using real ion signals obtained from the residual gas analysis system under development. The simulation results show that the proposed method is valid. |