738 THE BELL SYSTEM TECHNICAL JOURNAL, MAY 1954 



AMPLITUDE VS 

 FREQUENCY CHARACTERISTIC 



IMPULSE CHARACTERISTIC 



ENVELOPE P(t) 

 5 1 NTT to/7; 



(a) REPRESENTATION OF IMPULSE CHARACTERISTIC AS 

 ENVELOPE MODULATED BY WIDBAND FREQUENCY 



AMPLITUDE VS 

 FREQUENCY CHARACTERISTIC 



l* To — -^- 



MPULSE CHARACTERISTIC 



sVi/ I ^JV-f 



— Tq 1\* Tq -4* 7b *i 



Fig.: 

 mission 



(b) REPRESENTATION OF AMPLITUDE VS FREQUENCY AND IMPULSE 



CHARACTERISTICS, 3, AS THE SUM OF A POSITIVE LOW-PASS , 



CHARACTERISTIC,!, AND A NEGATIVE LOW-PASS CHARACTERISTIC, 2 



5 — Idealized band-pass characteristics and corresponding imjjulse trans- 

 characteristics. 



