ES430286A1 - Improvements in telephone systems. (Machine-translation by Google Translate, not legally binding) - Google Patents

Abstract

Improvements in telephone systems, and more particularly in coupling systems between a PAM time division telephone communication exchange (generally any PAM time division transmitter system) and a PCM time division transmitter system, for the formation of a bundle of outgoing communication channels that allow part of the telephone traffic dispatchable by the exchange, up to a maximum number of conversations equal to the number of voice channels in the PCM system, to be developed with users external to the exchange itself, characterized in that the circuit (CF) for the elaboration of the sound signal is made up of a plurality of bidirectional branches arranged in parallel with each other, each of which is associated on the one hand with an incoming and outgoing PCM sound channel while on the other hand is each time associated, in the act of connection, with a user of the local exchange interested in an external conversation, and n based on an allocation program developed by a switchboard processor; because the generic (i-th) branch the phone circuit (CF) includes; - a first capacitor (CA1) that exchanges, through the audio track (HSF) of the PAM telephone exchange, samples of the audio signal with the user interested in the external conversation transmitted through the branch under examination, while the appearance of the addresses relative to the user and to the branch (i-th) that is verified during a temporary phase of the central panel, determines the closure of a superinterrupter for access to the telephone circuit (SS) and of a phonic switch (I1) access to the particular branch directed in the recurring time phase; - a second capacitor (CBi) that exchanges samples of the audio signal with the first capacitor (CAi), during the closing intervals of a separation switch (S1) operated by a command generated in the timing of the PCM panel; - a branch that works with time division that allows to transfer the available signal in the second input capacitor (CB1) to an encoder (COD), through the closure of a transmission switch (IT1) arranged on the outgoing PCM line (U), and which allows charging the same capacitor (CB1) the signal level provided by a decoder (DEC) arranged on the incoming PCM line (E), through the closure of the reception switch (IRi), the transmission (ITi) and reception switch (IRi) piloted with commands generated respectively in the timing of the PCM frame in transmission and the PCM frame in reception, so that they house the bits corresponding to the encoding of the output signal, in the PCM transmitter channel associated with branch (i) and to extract the arrival signal from the corresponding reception channel; and because it comprises an alignment member (ALL) in which a delay line (L) insertable or insertable on the incoming conductor (E) of the PCM system and a logical control network piloted by the timing circuit of the PCM system are individualizable. and with a guard signal (G) that defines the field of variation between the PCM frame in transmission and the PCM frame in reception, whose actuation determines a realignment of the PCM frame in reception with respect to the PCM frame in transmission so that in each circumstance always be verified, for the above mentioned switches, the closing sequence: separation switch (Si) - > transmit switch (ITi) - > - receive switch (IRi), performed at successive time intervals different from each other. (Machine-translation by Google Translate, not legally binding)