mainly the matrix inversion that the straightforward calculations in eq 12 require one issue that determines the demanding load on the computations is the need to update for each slot the filter coefficients g j used in eq 6 this in turn is based on the need to use those paths in the rake receiver having the highest sir for each slot for symbol j in slot k u2212 n b corresponding filter coefficients g k u2212 m g k u2212 1 g k in g j have been determined over varying sir and velocity v values measured in kilometers per hour in a rayleigh fading channel with the results being plotted in the graph of fig4 the analysis shows that the values of the individual filter coefficients vary much more for f d variations than for sir variations therefore in accordance with one aspect of the invention the filter coefficients used in eq 6 are approximated by u011d x given by u011d x u03b1 x f d n sir n u03b1 x f d n u2212 1 sir n u2212 1 u03b1 x f d 0 18 where k u2212 m u2266 x u2266 k the polynomial u011d x is of degree n and fits the data u011d x g x in a least squares sense those having ordinary skill in the art will readily understand how to determine such.