TM No. 377 



Auto -Spectra of Wave Ifeter Eata 



Following are plots of the auto -covar lance spectra of the wave velocity 

 components measured with the wave meter systems. Curves are presented for 

 series OOI-I2U - BBELS-5 through BBELS-I6. (Series OI7 and 070 are not listed.) 

 On each plot the pertinent information is given for the particular measurement. 

 The statistical nomenclature is defined as follows : 



N = The number of interpolated data points. 



^ = The time interval spacing (sec) of the interpolated data; 

 WAT = the length of the record. 



m = Wumber of time lags for computation of auto -covar iance 



(and covariance function) and hence the divisions on the 

 frequency scale. The frequency resolution is 100 (2 mAT)~ 

 in millicycles per second. 



DF = The degrees of freedom calculated by the equation approx- 

 imately equal to — . By use of curves in figure 111-3^ 

 m 



the given value can be determined foranSofo confidence 

 limit band (assuming the spectral data are approximately 

 Gaussian distributed). 



Oy = The variance of the velocity component X [car sec j. 



X = The mean value of the quantity X (cm sec"-^) over the 

 sampling period N. 



The covariance of u' and w' at zero lag in cm^ sec"^ (given 

 for measurements of u and w only). 



The correlation coefficient in the case of OMDUM measure- 

 ments of u and w. 



W2): 



r(u,w) = ^^^— 

 ^77272 



V u w 

 In the case of LIMDUM measurements giving pairs of U3_ and U2 (or W]_ and 



Ui'Up 



ir'(u2^Uo) = — and similarly for w-[_ and Wg ■ 



Vv 



2 ? 



U2 



B-110 



