Bandwidth limited digital PCM transmission system - with frequency band divided in three zones, with phase correction better in middle zone

摘要

The system has a high-pass or a band-pass characteristic for transmission of a pseudo-ternary code using approx. sin2-shaped pulses of double bit width for regeneration. Frequency band to be transmitted is divided for phase correction into a core and two outer zones, whose limits are determined by dominant frequencies (f1, f3) representing spectral lines of those two pulse trains which contain all transient processes. Accuracy of phase correction in the outer zones is lower than in the core zone.