CHOICES IN THE EVOLUTION FROM ANALOGUE TO DIGITAL TRANSMISSION PLAN

摘要

The advent of digital techniques into the analogue network has a remarkable influence in terms of transmission quality;thus a careful planning of the digitalization process is required,strictly depending on structure and characteristics of the existing network.During the transitional period,a suitable strategy leads to a progressive improvement of transmission quality,and even in the worst cases the achievement of the analogue standards is assured.For the final stage of fully digital network between two local exchanges,the very high performances outlined by the most recent international guidances are guaranteed.In this paper some suitable choices are presented for an average-sized country,as Italy,with a large network developed in accordance with the CCITT Recommendations.