which can be written 
exp,firr(cos(9-g)- cosy fa 
y 
iT 
4 
vw) a—, va 
This integral yields* 
T 
2 
R = Tro ( 2krsing tyr | sin| 2irsingsin( 9-5 )|ag 
in 
2 
In general it; =-6@, Ga — 6 areythe limits of integration, 
the directivity function will have the form 
R = 28rJo (2)+g(2)+ inl) 
For example, this is the case when § = 7/3. 
(e) Circular Disk 
Applying equation (6) to the case of a circular disk (fig. 11), 
and letting 3 = 7m Cos?, Y = rsing 
Rie ij | 20. y) 
A 
expjzLr{cos g(cosa- cosa )+sing(cos8-cosBo )} 
+o(r, g(cos\(r, @)-1) ]}rdrdg 
“Reference 3) page ts 
33 
