A local modulation signal bispectrum for multiple amplitude and frequency modulation demodulation in gearbox fault diagnosis

This paper proposes a novel multiple amplitude modulation and frequency (AM–FM) demodulation method based on local signal bispectrum (LMSB), which can demodulate the fault features of different components from gearbox with multi-mesh bands multi-modulation components. Firstly, collected measurement is decomposed into series sub-band signals, generated signals are demodulated by (MSB), realizes simultaneous Subsequently, each resulting MSB synchronously averaged to generate LMSB, removes random noise interference frequencies signals. Finally, periodic intensity (PMI) utilized evaluate ability LMSB multi-component AM–FM The effectiveness in processing demonstrated numerical simulation experimental analysis. Analysis results demonstrate superiority compared MSB, envelope analysis (EA) Teager energy operator (TEO). research provides perspective for detection.