COUPLED WAVE THEORY AND WAVEGUIDE APPLICATIONS G81 



1.0 



0.8 



0.t77 0.2 77 0.3 77 0.4 77 0.577 0.677 0.777 0.877 0.977 77 



CX IN RADIANS 



Fig. 17 — Wave amplitude and phase factors versus ex when the coupled lines 

 have equal attenuation constants but unequal phase constants. 



where 



E.y 



/^ 



- ^^y 



4c2 



+ 



- - [^(A 



+ /32)- 



4c2 



+ 1 CX 



(32) 



The major effects of couphng in this case are represented by £"1* and E2*, 

 which are plotted in Fig. 17 for several values of (/3i — (32). As (0i — ^2) 

 becomes different from zero, the maximum power transferred from the 

 driven line to the undriven line decreases, and the period of the cyclical 

 \'ariation in amplitude is reduced. The latter period is the value of ex 

 given by 



/ 



(gi - ^2)^- 

 4c2 



+ 1 CX = TT 



(33) 



The driven and undriven-line wave amplitudes E* and E-* at the max- 

 imum power transfer point, namel}^, at 



\/'- 



(81 - Bo)- TT 



(34) 



