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Fourier series directional distribution was plotted over two degree 

 increments for the three bands of highest energy and is presented in 

 Figure IV-7. The analysis program demonstrates its ability to define 

 each wave train's direction accurately by presenting the maximum 

 energy at the correct simulated wave direction. The half-power 

 directional width of each is approximately 60 degrees. These curves, 

 of course, do not contain all of the simulated^^ave energy since only 

 three major spectral bands are plotted. 



Two wave trains of different frequency but with identical 

 height and direction were next simulated over 512 points of 0.25 

 second interval. The frequency of each was selected to fall exactly 

 between two spectral frequencies. The higher frequency bands were 

 0.118^ rad/sec apart and the lower were 0.46A rad/sec apart. The raw 

 energy spectra, shown in Figure IV-8, depicts the two wave trains' 

 energy distribution over frequency. Slight differences in leakage 

 between the two simulated wave frequencies can be detected. The 

 non-smoothed directional distributions of the two waves, shown in 

 Figure IV-9, agree well with each other as expected. The very slight 

 differences are the result of differences in spectral leakage for 

 each wave. 



The analysis procedure, however, is unable to differentiate 

 between two waves of identical frequency and different direction. 

 Two waves of the same height and non-spectral frequency were 

 simulated with a 130 degree difference in direction. The 



