1. Institute of Electrical Engineering, Yanshan University, Qinhuangdao, Heibei 066004, China;
2. Key Laboratory of Measurement Technology and Instrumentation of Hebei Province, Yanshan University, Qinhuangdao,Hebei 066004, China;
3. Qinhuangdao Institute of Measurement and Testing, Qinhuangdao, Hebei 066004, China
Abstract：The ordinary blind source separation (BSS) methods is based on the assumption, which the number of observation signals is no less than that of the source signals. The result of BSS will be relatively poor when the number of observation signals less than source signals. However, the problem of underdetermined BSS, even single observation channel BSS, is common in vibration signals of rotating machinery.To solve the single observation channel problem, a new BSS method based on extremum field mean mode decomposition (EMMD) is proposed.Firstly, by EMMD, the underdetermined observation signal is decomposed to a series of intrinsic mode function (IMF), then the underdetermined observation signal and IMFs compose multi-dimensional signal, to increase the dimensions of observation signals.Secondly, the number of source signals is estimated with singular value decomposition and Bayesian information criterion.〖JP2〗Finally, the characteristic matrix joint diagonalization method based on fourth-order cumulant is used to achieve BSS.The simulation study on rotating machinery fault signal indicates that it can well solve the problem of BSS with underdetermined observation signal.
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2013, Vol. 34 
