Hilbert–Huang analysis of BWR neutron detector signals: application to DR calculation and to corrupted signal analysis

In this paper, we present an application of the empirical mode decomposition method [Proc. R. Soc. Lond. A 454 (1998) 903], to the stability analysis of BWR. The methodology developed in this paper decomposes the original time series data in intrinsic oscillation modes or IMFs. Then we compute for each IMF, its Hilbert amplitude spectrum and its Hilbert marginal spectrum. From the intrinsic mode related to BWR stability we have obtained by ordinary autoregressive methods the decay ratio value and the oscillation frequency. Also we have proven that the original signal can be reconstructed with seven IMFs and that this modes are mutually orthogonals.