Circuit arrangement for telecommunications exchanges, especially telephone exchanges, which are constructed partially using space division matrix technology and partially as time division multiplex coupling arrangements

摘要

Expansion units (P, R) for telephone exchanges (L) which are constructed from group and line selectors (I.GW, II.GW. III.GW, IV.GW, LW) using conventional technology are constructed using PCM technology from in each case one line trunk group for digital subscriber points (LTGB1, LTGB2) and one line trunk group for analog subscriber points (LTGA1, LTGA2) and a digital concentrator (C1, C2) which is connected to the line trunk group for digital subscriber points (LTGB1, LTGB2), the two line trunk groups in one expansion unit (P, R) in each case being directly coupled together by means of their connections which are provided for connection to a PCM coupling network. The line trunk group for analog subscriber points (LTGA1, LTGA2) is connected to inputs of II. group selectors (II.GW) by means of its analog outputs (d), and is connected by means of its analog inputs (g) to outputs of group selectors of the same selection stage (II.GW) or a downstream selection stage (IV.GW). A central control mechanism for expansion units is superfluous in the expansion phase. IMAGE