N-1 N-1 u 
SY CeDiO=s > > 10 (2.72) 
r=—(N-1) u=0 r=—u 
sin} (u ++ 
S yi ( hg (2.73) 
cosrp = we 
r=—u sin(i) 
a sin{(u+4)o} sin?( %¢) 
EN ea a eae (2.74) 
u=0 sin(+¢) sin’(#) 
Then from these relations, 
N-1 N-1 
ats y 1 pi cosrp@ = as » {N- Ir} cosrp 
IE TN Ny N27 r=—(N-1) 
N-1 1 sin 44) 
—_~ = F.,(¢). (2.75) 
This function is called the Fejer function F.,(@) and has the form shown in Fig. 2.9. 
NO 
When or ee 6, 
1 sin* @ N { sin@ 
F..(), 2s eee 
v@) near @ OaN sin?($) 3 ( 6 
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