A timing and memory sizing study for wavenumber analyzer

It is desired to perform frequency-wave number analysis on data from a PxQ element hydrophone array. It is assumed that the array may be mapped onto a plane, a sector of a sphere or a sector of a cylinder. A 3-dimensional frequency-wave number, averaged spectrogram is to be computed. The computation is to be performed using a VAX 11/780 mainframe computer in combination with an FPS AP-120B floating point array processor. All input, output and intermediate data is to be stored on RP06 disk drives. This report presents an evaluation of computation time, AP120B array processor memory requirements and disk storage requirements as a function of N=PxQ and M, the number of frequency cells to be analyzed. The evaluation is based on a preliminary software design with the intent of obtaining "order of magnitude' sizing extimates. Equations are presented relating computation time and disk storage requirements to P, Q and M independently for both the temporal processing (time to frequency computation for each hydrophone waveform) and the spatial processing (2-dimensional wave number computation for each frequency cell selected). The equations have been evaluated using BASIC and the BASIC programs have been included along with representative results for selected values of P, Q and M.