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BELL SYSTEM TECHNICAL JOURNAL 



with Z21 dependent through the inverse network relation ZnZ-n = R-. 

 This relation, besides ensuring a constant resistance iterative im- 

 pedance, reduces the network parameters at least one half. Since 

 resistances occur explicitly in the structures, these sections will all he dis- 

 sipative. 



The network of the lattice type, shown in Fig. 4, is symmetrical 

 and has a propagation constant determined by 



^// ^zrR 



Fig. 4 — Lattice type constant resistance section. 



^ _ 1 + z,,l2R 



^ 1 -2u/2i?' 



(13) 



where S11Z21 = R^- If 2ii i^ o, reactance, the network will introduce no 

 attenuation, only phase difference. 



The networks of the hridged-T type are symmetrical and will be given 

 in two groups, the members of each group having the same propagation 

 constant. The two sections of the first group (/„ and h) in Fig. 5 



L 



a 



c^/ 



Z11 



en 



o-i— o-vwv-o- 



I — oVMro — ' 



cn 



o-'\AV^-o— A— o 



•^2J 



Zj/Zzi R 



=T>2 



Fig. 5 — Bridgecl-T(I) type constant resistance sections. 



