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BELL SYSTEM TECHNICAL JOURNAL 



4. 



and 



K = 



R' + JL'ui 

 G' + iC'co ' 



(smooth line) ; 



Zu = niR' + iniL'oi, 

 1 



(52) 



221 = 



(wC + imC'ui) 



Another possible simple pair is that in which Zu is a resistance and 

 Z21 is either series resistance and inductance in parallel with series 

 resistance and capacity or parallel resistance and inductance in series 

 with parallel resistance and capacity. These impedance elements 

 maybe used in the lattice or bridged-T (II) type structures where the 

 impedance element K is not explicitly required. Extension to more 

 complex structures can be made by the methods of Section 2.3. An 

 application will be given in Section 4.7 which considers the simulation 

 of a smooth line. 



Owing to the much greater inherent difftculty of physically realizing 

 inverse networks of impedance product K- when K is not R, the 

 generalization does not add much practically for our purpose, but 

 some structures in which K is not R may be of utility under particular 

 conditions. 



Part 4. Applications 



4.1. Complementary Distortion Correcting Networks 

 The pair of networks in Fig. 8 illustrates in a very simple manner 

 the general relations given in Section 2.85, as well as ideal distortion 



r-oAA/V-«>-i 



R'^-^^^(^4wiM 



Fig. 8 — Distortionless composite network. 

 (Broken lines indicate the other series and lattice branches, respectively identical). 



correction over the entire frequency range. When placed in tandem 

 they represent a composite network whose attenuation constant is 

 uniform at all frequencies and whose phase constant is zero, which are 



