AN INVESTIGATION OF BIASES IN THE FULL SPECTRAL-ANALYSIS TECHNIQUE

The full spectral analysis (FSA) technique is investigated using both experimental and model-generated data. The relationship between the fo rmulae presented by different authors is discussed, and the similariti es and differences inherent in using these formulae are evaluated. The FSA is applied both to sample spectra calculated using individual tim e series records and to spectra produced by the incoherent average of the sample spectra. The results reveal that the velocities obtained us ing sample spectra call be significantly biased in the situation where large turbulent motions exist for two particular implementations of t he technique. These biases are shown to decrease as the number of samp le spectra used in the incoherent average are increased, thereby produ cing FSA velocity estimates in excellent agreement with those produced using the full correlation analysis (FCA) technique.