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THE BELL SYSTEM TECHXICAL JOURNAL, MAY 1954 



by the dashed hnes in Fig. 15. With a gradual cut-off, however, the phase 

 characteristic will be nearly linear and have a finite slope, so that the 

 above pulse transmission rate can be realized provided ^o = zLmr. The 

 same pulse transmission rate can also be attained with vestigial side-band 

 transmission, discussed in section 14. 



Another particular case of interest is that shown in Fig. 16, in which 

 Um = 2us ■ In this case (4.08) becomes with \po = zLnw and with P(t) as 



UJm = 2COS 



FREQUENCY 



(a) FREQUENCY CHARACTERISTIC 



ENVELOPE P(t)/ 

 / 



coso^mtPlt) — -/- 



-1^"- T, = l/2fs 



WITH PULSES TRANSMITTED AT POINTS I, 2, 3 THERE 

 IS NO MUTUAL INTERFERENCE BETWEEN PULSE PEAKS 



(b) IMPULSE CHARACTERISTIC 



Fig. 16 — Particular case of symmetrical band-pass characteristic for which 

 , = 2w, . 



