The automatic telephone exchange МТ-20/25. The basic functional blocks of system replication

Station MT-20/25 concerns to the electronic equipment of the fourth generation with the centralized management. In it elements of an artificial intellect (self-diagnostics and self-restoration at a program level) are used. Special programs of a software find out and locate any damage which has arisen at station, make reconfiguration systems for exception of the faulty block and carries out distribution of the information on type and a site of malfunction.

The basic functional blocks of system replication. All this provides high stability of work of system. The system represents subscribers up to 13 additional services.

The first  automatic telephone exchange МТ-20/25 was issued in 1985 and  was executed on an import complete set and the basic constructional materials, and some stations on the mixed complete set in 1987. On end of the state tests of pre-production model telephone exchange МТ-20/25 on domestic components and materials the industry has begun since 1988 a batch production domestic МТ-20/25. Station МТ-20/25 it is compatible with automatic telephone exchange practically all types, the architecture of station allows a message its further development.

Electronic automatic telephone exchange MT-20/25 – the digital switching system intended for use on city telephone systems of the country. The station consists of a switching field, central managing device (UCD), or managing computer complex, a subscriber's step, the equipment of interface to other automatic telephone exchanges, the equipment of the signal system and synchronization.

The equipment of switching consists of switching field (RCX), the device of interface (TR). Management TR carries out the peripheral program device of the passive control of connection (PPC). The switching field consists of groups time (GT) and spatial (SG) switchboards and elements of the coordination of reception (ICR) and transfers (ICE.) GT cope the peripheral programmed device of marks of field (PPM).

URA - the concentrator, is a user's step with an opportunity of connection up to 763 subscriber's lines. Concentrators are two types: local, installed directly on station, and removed, installed in places of a concentration of subscribers, thus it is necessary to organize all 2÷6 lines PCM.

The station generator is applied to synchronous work of devices of station, developing clock pulses with frequency 8,192 MHz.

The equipment of the signal system and interface are necessary for reception and transfer of linear and managing signals. Linear and managing signals are transferred on colloquial paths and the allocated alarm channels. For connection with the concentrator the signal system on the allocated alarm channel such as "semaphore" which capital equipment is the peripheral program device signaler PPSVV is used.

For visualization of emergency signals the station board having the light and sound signal system is used. The peripheral program device of alarm system (PPA) is applied to connection telephone exchange with station board.