A low order implementation of the Polyreference Least Squares Complex Frequency (LSCF) algorithm

Recent presentations by several authors concerning a Rational Fraction Polynomial (RFP) algorithm with a new complex frequency mapping, called the Polyreference Least Squares Complex Frequency (LSCF) and referred to commercially as the PolyMAX algorithm, have demonstrated an interesting modal parameter estimation algorithm that has optimal numerical characteristics for a high order frequency domain method. This paper explores this algorithm, evaluating the performance against both theoretical and experimental data cases, paying particular attention to the impact of residuals on the final modal parameter estimates. Comparison to other modal parameter estimation algorithms is also included. In particular, a low order implementation is evaluated and compared to historical low and high order algorithms in the frequency domain in order to determine the advantages and disadvantages of using this algorithm.