OPTIMAL SYSTOLIC ARRAYS FOR REAL-TIME IMPLEMENTATION OF THE MODIFIED COVARIANCE SPECTRAL ESTIMATOR

The Modified Covariance method of spectral estimation, proposed as a replacement of the conventional short term Fourier transform for use with pulsed Doppler ultrasound blood flow detectors in order to improve time/frequency resolution, is computationally far more demanding. The use of an application specific architecture for real-time implementation is of interest. A cost/benefit selection of systolic arrays, firstly for a matrix solution method with suitable bus width and secondly for calculation of covariance matrix elements, led to the choice of Cholesky matrix decomposition, 12 bit bus width and a bi-linear systolic array designed using a data dependence graph method.