SU1160577A1 - Synchronizing device - Google Patents

Description

The invention relates to communications and is intended for use in systems for the transmission of telemechanical information, using a temporary seal and separation of communication channels and pulse-width modulated signals (PWM)

The aim of the invention is to improve the noise immunity.

FIG. 1 shows a block diagram of a synchronization device; in fig. 2 - timing charts of the synchronization device.

The synchronization device contains a decoder 1 channel sync signal, a waiting multivibrator 2, a switch 3 channels, a decoder 4 measuring signal, driver 5 pulses, combinational matrix 6, switch 7 groups of message sources, generator 8 pulses, driver 9 cyclic sync signal, channel converters 10 £ GO / smoothing chains 1 P-1 Ts /

The synchronization device operates as follows.

The group signal at the input of the device (Fig. 2a) acts on the decoder 1 of the channel sync signal and the decoder 4 of the measuring signal. The waiting multivibrator 2 of the reception circuit of the channel sync signal is excited for a time equal to the expected interval between channel sync signals in the ίth group of message sources. From the outputs of the switch 3 channels and shaper 5 pulses, the control pulses act on the combination matrix 6, which also receives control pulses from the switch 7 of the message source groups, the switching frequency of which is determined by the frequency of the pulse generator 8 (Fig. 26). When choosing the frequency of the generator 8 pulses, the presence of the inevitable protective interval Tz is taken into account. _and , between groups of PWM signals, which favors the creation of a gating mode for individual groups of PWM signals from geographically separated sources of messages with the help of output pulses of a switch of 7 groups of sources of messages, the switching times of which should correspond approximately to the midpoints of protection intervals Tz, c. Shaper 9 cyclic clock signal is triggered by the falling edge of the Ν-th control pulse of the switch 7-group of message sources. pulses, the output pulses of which are fed to the second input of the shaper 9 cyclic sync signal, the output of which is a signal on the reverse communication channel ne It is transmitted to N information transmitters.

When using gating frames, the distortion or disappearance of any number of information pulses within one of the groups of PWM signals, which occurs in channels with error grouping, does not lead to failure of channel synchronization and incorrect reception of information in subsequent groups of PWM signals.

Thus, the proposed synchronization device eliminates the effect of synchronization failure in separate groups of PWM signals on subsequent groups, which leads to an increase in the noise immunity of the synchronization device as a whole.

In the absence of a gating mode, the probability of channel synchronization failure can be considered proportional to the number of time channels used, i.e. K. In the case of gating mode, the probability of channel synchronization failure is approximately proportional to the number of time channels in one group of sources, i.e. K. Improving noise immunity is determined by the ratio

= Ν.

1160577

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Claims (2)

A SYNCHRONIZATION DEVICE, containing a series-connected channel sync signal decoder, a waiting multivibrator and a channel switch, the outputs of which are connected to the corresponding inputs of the combination matrix, each output of which is connected via a channel converter to the input of the corresponding smoothing circuit, as well as the decoder of the measuring signal, the input of which is combined with the input of the decoder of the channel sync signal and is the signal input of the device, characterized in that, in order to improve noise immunity, a pulse generator, a switch of the message source groups, a driver are introduced cyclic sync signal and pulse shaper, while the output of the pulse generator through the switch of the message source groups is connected to the corresponding additional inputs of the com Nazioni matrix, Ν-th additional input of which is combined with the first input of the cyclic clock signal to the second input of which is connected to the output of the pulse generator, and the output measurement signal of the decoder via a pulse shaper is connected to the corresponding input combination matrix. § 1160577 FIG. one I160577 2