SU1072262A1 - Conference-type communication switch device - Google Patents

Abstract

COMMUTATION DEVICE FOR CONFERENCE COMMUNICATION, containing m encoders,.-Tt) decoders, m shift registers, 2jrn elements AND (m is the number of conference subscribers) and the switching field, the first inputs of which are connected to the outputs of the encoders, , and the first outputs - with the inputs of shift registers, the outputs of which are connected to the inputs of the elements AND, the second outputs of the switching field are connected to the inputs of decoders, characterized in that, in order to increase the noise immunity, two three-level adders and a polarity converter are introduced into it , at the output of which is connected to the second input of the switching floor, and the inputs to the outputs of the adders, the inputs of which are connected to the corresponding outputs of the elements I.

Description

The invention relates to automatic telecommunications and can be used for organizing a conference communication.

Priority conference devices are known, I containing multipliers, a switching field, coders and decoders l.

The drawbacks of such devices are the low naturalness, intelligibility and efficiency of the conference.

The closest to the present invention is a switchgear for a konyerents-communication, containing m encoders, m decoders, m shift registers, 2 elements I (t is the number of conference subscribers) and the switching field, the first inputs of which are connected to the outputs of the encoders, and the first exited with the inputs of shift registers, the outputs of which are connected to the inputs of the elements AND, the second outputs of the switching field connected to the inputs of the decoders 2.

The disadvantages of the known device are low noise immunity and high information transfer rate, depending on the number of conference call sites.

The purpose of the invention is to improve the noise immunity of the device.

The goal is achieved by the fact that in a switching device for a conference communication, containing t encoders, t decoders, the number of shift registers, 2 I1 elements I (t is the number of conference subscribers) and the switching field, the first inputs of which are connected to the encoder outputs and the first outputs - with the inputs of the shift registers, the outputs of which. They are connected to the inputs of elements I, the second outputs of the switching field are connected to the inputs of decoders, two three-level adders and a polarity converter are input, the output of which is connected to the second input of the switching field, and the inputs to the outputs of the adders I.

Fig. 1 shows a structural electrical circuit of a switching device for a conference; 2 shows timing diagrams for his work.

The conference switching device contains encoders 1, switch 2, shift registers 3, elements AND 4, three-level adders 5, polarity converter 6 and decoders 7.

On time diagrams (figure 2) marked DM signals CHC (t), H; (t), ..., H (t), ..., Yn) (t) at the outputs of the If code, the signals H () and Yg (t)

correspond to the DM signals of active simultaneous speakers at the moment subscribers, and the signals Uch (t) and Lt (-b) - to the signals of idling of the coders; signals y (t) -, (t) at the 5 output of the three-level adder 5 and the signal V (t) at the output of the polarity converter 6.

The conference switching device operates as follows.

0 way.

Speech signals U (t) -Uf4 (t) are converted by encoders 1 into delta-modulated frequency codes, (i) -Yf (t) (Figure 1), which through switch 2 arrive at shift registers 3. Shift registers 3, together with elements 4, perform the function of analyzers of DM signals; as a result of analyzing and processing DM signals, the bursts of characters H in the active subscriber signal Ta are converted into bursts of characters, but the unit bursts are shortened in length by one character (signals ) 47 (t)

5 (in Fig. 2), packs of symbols O in the signal of the active subscriber convert into packs of symbols, and the packs are also shortened in duration by one symbol (signals 4i (-t), h; (i), in Fig. 2) The alternate combinations of symbols 1, O (0/1) are converted at time intervals of their presence in O (signals Y (-t), Yi (t) in FIG. 2).

All signals of passive subscribers

5 Lh (-b), V (-fc), ... Y; (i), H, (t), ..., V (-l) / Ytl. (-T). (big.1) are equal to O, i.e. alternate combinations of characters 1.0 passive subscribers do not arrive at three-level adders 5

0 and do not add up to active subscribers, which significantly increases the signal-to-noise ratio. Thus, in the three-level adders 5, only the useful information contained in the active subscriber signals (signals (b) (t) in FIG. 2) is carried out 2, since the no-load disturbance of the encoders is converted to a voltage Q equal to zero. As a result of the linear summation, the signal level increases, however, the frequency band occupied by the group signal remains equal to the frequency band occupied by one DM signal, i.e.

 The signal transmission rate in the group path, in contrast to the prototype, does not depend on the number of participants in the conference communication. An increase in the level occurs only at one time activity of two or more subscribers, in a case that is rare for practice, since basically during a conference connection, only one subscriber transmits a message to everyone else.

5 Situation of simultaneous activity

Two subscribers occur when a higher-priority subscriber interferes with the conversation to send an important message and his voice must be recognized against the background of the voice of the first subscriber, who immediately stops sending the entire voice message. Therefore, in the UN signals (f (t) and F (t) are two-level. When unipolar signals C) (t) and Vl are received on the polarity converter b, two operations are performed: converting the signal to a similar signal of negative polarity and summing it with a signal (, (t).

P a result of this operation, at the output of the polarity converter, a two-pole signal (j ((i)) is generated, which through the electrical contacts of switch 2 are sent simultaneously to all decoders of the 7 participants in the conference communication.

Since the decoder is based on the integrator, the last speech signal at the output of each decoder is restored when two subscribers are active or the signal of one subscriber is active. Unlike the prototype output decoders in. The proposed device should not turn on amplifiers, since it lacks the operation of dividing DM signals in time, resulting in a decrease in the output signal level proportional to the number of participants in a conference call.

Thus, the proposed com mutation device for conferencing compared to the prototype has a higher noise immunity due to the exclusion of paused combinations of DM signals and high

0 level of recoverable signals, as well as a low data transfer rate in the group path.

Claims (1)

COMMUNICATION COMMUNICATION DEVICE 'FOR CONFERENCE COMMUNICATION, containing m encoders, P) decoders, t shift registers, 2sh elements And (t is the number of conference subscribers) and a switching field, the first inputs of which are connected to the outputs of the encoders. and the first outputs · - with the inputs of the shift registers, the outputs of which are connected to the inputs of the AND elements, and the second outputs of the switching field are connected to the inputs of the decoders, characterized in that, in order to increase noise immunity, two three-level adders and a polarity converter are introduced into it, whose output is connected to the second input of the switching field, and the inputs are to the outputs of the adders, the inputs of which are connected to the corresponding outputs of the elements I. I SU ,, „1072262