Modal deflation procedure for parameter estimation

Multi-degree-of-freedom parameter identification techniques compute all modes in the frequency range simultaneously. Often, small or weak modes are overshadowed by strong modes and are difficult to curve fit. Modes with significantly less magnitude than their neighboring modes are considered small or weak modes. High damping, insufficient excitation, or local modes may make certain modes weaker. A procedure that deflates strong modes from the frequency response function data set is developed to help estimate these weak modes. The modal deflation procedure is implemented into the complex mode indication function parameter estimation method.