756 



THE BELL SYSTEM TECHNICAL JOURNAL, MAY 1954 



Table I — Amplitudes of Echoes, /„(6) 



lar case the maximum amplitude h is at the maximum frequency wmax 

 = 2wi , so that sin wr = 1, or wr = 7r/2, for w = 2wi . Hence the interval 

 between pulse echoes is r = 7r/4coi = l/8/i . The interval r is accordingly 

 }4, the interval n •= l/2/i required for the pulse Po(t) to reach zero ampli- 

 tude in the absence of phase distortion. 



PHASE 

 CHARACTERISTIC 



AMPLITUDE CHARACTERISTIC 



ENVELOPE DELAY 



'^-brcos ur 



■-- — t "' 



Fig. 21 — Particular case of sinusoidal phase deviation. 



