i.o.ini:/) Lis'iis .iM> coMi'r.xs.iiiM; sr.rifOKKs 445 



Tlu- amount by which tin- rharactt-ristic impcilance of ain- [u-ri- 

 o<licaIly hiaded Hue exceinls the impedance of the corresponding non- 

 dissipati\e loaded line will he termed the "excess impedance" (or, 

 more fully, the "excess characteristic impedance"); and a network 

 for simulating; it will be termed an "excess-simulator." Excess- 

 simulators for loaded lines will be considered very briefly in Part V'll. 



(In passing, it may be noted that the foregoing defmition of the 

 "excess impedance" of a pericxlically loaded line properly includes 

 the definition already gi\en ' of the excess impedance of a smooth 



"i Excess- - Basic I 



•r l- l network I '^' 



Hsimulator 



Buid«ig-out H Cxcess- 

 Structurt - simulator 



H Basic 

 networ( 



(b) 



•J511 



Cxcess- 



HBuWing-outt-r 

 structure l -l 



Basic 

 network 



•ffluiWinq-out H" 

 structure t — I 



Eicess- HBuMmg-out H Basic I ^^^ 

 Simulator H slructura N network I 



KIg. 



II — Abstract Di.igr.im?; of Complete Networks lor Sinuilating t haracteristic 

 Impedance of Loaded Line 



line: for the "nominal impedance" of any smooth line was defined ' 

 as the impedance of the corresponding non-dissipative smooth line. 

 A similar statement is applicable to the terms "excess simulator" 

 and "basic network" previously defined ' for smooth lines.) 



The foregoing considerations and definitions have prepared the 

 way for Fig. 11, which indicates in an abstract manner how the im- 

 pedance of any loaded line having any relative termination can be 

 simulated by combinations of basic networks, excess simulators, and 

 building-out structures. 



Fig. 11a corresponds to the simple but unusual case in which the 

 loaded line has the basic relative termination: its impedance then 

 can be simulated by the corresponding basic network and excess 

 simulator, without any building-out structure. 



When, as usual, the given line does not have the basic relative 

 termination, there are available the two natural alternatives repre- 

 sented by Figs, lib and lie. Fig. lib shows the whole network 

 of Fig. 11a built-out to the relative termination of the given line by 

 means of the requisite building-out structure, which for the highest 

 precision must be dissipative to correspond to the actual line. In 

 Fig. lie the basic network is built-out to the relative termination of 

 the given line with a non-dissipative building-out structure: and then 

 the resulting network, which simulates the impedance that the actual 



