Embodiments of the present invention provide techniques for decomposing a signal using a sawtooth, or triangle wave, transform. Specific embodiments transform an input signal into a piecewise-linear sawtooth or triangle wave function, and construct upper and lower envelopes for the input signal in sawtooth...http://www.google.de/patents/US7747401?utm_source=gb-gplus-sharePatent US7747401 - Fast intrinsic mode decomposition of time series data with sawtooth transform
