Measuring spectra using burst-mode LDA

The phrase ``burst-mode LDA'' refers to an LDA which operates with at most one particle present in the measuring volume at a time. For the signal to be interpreted correctly to avoid velocity bias, one must apply residence time-weighing to all statistical analysis. In addition, for time-series analysis, even though the randomly arriving particles eliminate aliasing, the self-noise from the random arrivals must be removed or it will dominate the spectra and correlations. A flaw in the earlier theory [1],[2], the goal of which was to provide an unbiased and unaliased spectral estimator from the random samples, is identified and corrected. The new methodology is illustrated using recent experiments in a round jet and a turbulent boundary layer. \\ 1. Buchhave, P. {\bf PhD Thesis}, SUNY/Buffalo, 1979. \\ 2. George, W.K. {\bf Proc. Marseille.-Balt. Dyn. Flow Conf. 1978},757-800.