The basic principle of independent component analysis(ICA) and its application in the noise separation for diesel engines are introduced.The FastICA algorithm,which is widely used for processing engineering problems,is carried out.The noise signal of a 6-cylinder diesel engine under a pilot-injection condition were measured according to the national standard and analyzed by ICA method.It is shown that 3 mutually independent components of noise are originated from piston knocking,pilot-injection and combusti...