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BELL SYSTEM TECHNICAL JOURNAL 



shown on Fig 1. Now the phase of each component in such a spectrum 

 is so arranged that the spectrum forms a series of cosine terms all of which 

 have zero phase angle at the center of the pulse. From successive pulses T 



2C 3C 4C 5C 



FREQUENCY, f, IN TERMS OF C (WHERE C^^t) 



Fig. 4 — Determination of spectrum of single half sine wave by modulation of single pulse 



spectrum with cos licet. 



seconds apart, the component at any given frequency will have the same 

 amplitudes, but the relative phases will be 1-kJT radians apart. It is appar- 

 ent that frequencies for which lirjT is 2x or some multiple of 27r radians 



