SU660289A2 - Arrangement for synchronizing code combinations defined by standard trains - Google Patents

Description

the course of which is connected to the zero inputs of two triggers, the single inputs of two triggers and the control input of the AND element are inputs of the error indicator, and the outputs of the AND element and the exclusive OR element respectively of the output of the error indication. In the drawing: structural diagram of the proposed device .

The device for synchronization of code combinations limited by standard pauses contains an unmanaged oscillator 1, a frequency divider 2 impulses, a phase discriminator 3, a control unit divider 4 pulse frequencies, a feedback circuit 5, a distributor 6, a mismatch indicator 7, which consists of two Triggers 8 and 9, Exclusive Element, OR 10, Element 11, and Differential Chain 12.

The phase discriminator 3 contains AND elements 13 and 14, elements OR 15 and 16, counters 17 and 18, and a comparison block 19.

The control unit of the divider 4 is composed of elements And 20 and 21. The feedback circuit 5 consists of elements And 22 and 23.

The device works as follows. The distributor 6 at its outputs forms three gating series of pulses a, b and c. The received signals of the code combinations are fed to the first inputs of the And 13 and 14 elements, to the second inputs of which gates pulses a and b are received, respectively. The third inputs of the elements 13 and 14 are fed counting pulses from one of the outputs of the controlled frequency divider 2.

At the synchronous position of the transmitting and receiving distributors, the gating pulse series a, b and c are oriented in time relative to the received code combination. In this case, the counting pulses to the outputs of the elements And 13 and 14 do not pass. At the end of each operation cycle of the distributor 6, the back edge of the strobe through the differentiating circuit 12 triggers 8 and 9 are set to the zero state.

When there is a mismatch between the transmit and receive distribution pins, the signals of the received code combination can coincide either with gate a, or gate b, or with both cfpb.

The latter case corresponds to the presence of a large angle of mismatch between the transmitter and receiver distributors. When the received code combination coincides with the strobe, and the counting pulses pass to the output of the element And 13 and through the element

OR 15 arrives at the input of counter 17, simultaneously triggering trigger one. If the received code combination coincides in time with gate B, then the counting pulses pass to the output of the element 14 and through the element OR 16 arrive at the input of counter 18, at the same time switching to a trijrep 8 state.

Comparison unit 19 compares the number of pulses recorded in the counters 17 and 18. Depending on which of the counters contains the largest number of pulses, the comparison unit 19 outputs a signal to either the element 20 and the element 21. 20 and 21 a pulse is transmitted from the distributor 6, to the third inputs of these elements a signal comes from the output of the element exclusive OR 10 of the error indicator 7. E-if during the operation cycle of the distributor 6 there is a small mismatch between the transmitter and the receiver, then moment the appearance of strobe c is present at one of the outputs of comparison block 19. At the output of the element, an exclusive OR 10 also has a resolving signal, since at a small error angle the code combination signals coincide either with gate a or gate b, which during the cycle triggers only one of the triggers 8 or 9, respectively. Therefore, during the operation of the strobe with the output of one of the elements AND 20 or 21, the control signal of frequency divider 2 takes place. In this case, the counting pulses from the second output of the controlled frequency divider 2 through one and the elements 22 and 23 and one of the elements OR 15 or 16, respectively, are passed to refill the counters 17 or 18, aligning the values of the numbers of pulses recorded in the latter. When these values are compared at the output of comparator block 19, the signal disappears and the correction of the counting factor of frequency divider 2 stops. At the end of each cycle, the counters 17 and 18 are set to the zero state by a special reset pulse.

Thus, the phase correction at small error angles is performed without overshoot.

The trailing edge of the gate through the differentiating circuit 12, the trigger 8 or 9, is transferred to the zero state.

Claims (2)

If during the cycle of operation of the distributor 6 there is a large mismatch between the transmitter and the receiver, then by the end of the cycle, at least one pulse of the received code combination coincides with both gate a and gate b. At the same time, at the moment of occurrence of the output at the output of the distributor 6 of the gate c, regardless of the state of the outputs of the comparator unit 19, the counting coefficient is controlled through an AND 11 element in one direction with a maximum step. At the output of the element, the exclusive OR does not have a signal, since during a cycle both triggers 8 and 9 are switched to one state. At the end of the strobe, both triggers are switched to the zero state as described above. If, on the other hand, the structure of the code combination is such that even with a large matching, the received signals coincide only with gate a or b, which is possible with significant code asymmetry. If the signals are relative to their midpoint, then in this case only one of the triggers 8 or 9 is switched, and the device, during the operation of the system, works as with small mismatches, gradually correcting the phase of the distributor before entering synchronization. However, due to such asymmetry of the code combination, the difference in numbers in the counters 17 and 18 by the end of each cycle is maximum and the correction process is carried out without overshooting, but in large steps, close to the maximum. At any value of the code combination fill factor and any degree of symmetry about its midpoint, the signal at the output of element -11 11 appears only if indeed 896 there is a large discrepancy angle between the transmitter and receiver distributors. Thus, the operation of the device is robust, and false phasing conditions are eliminated. Claim 1. Device for synchronization of code combinations, limited to Standard pauses, by author. St. No. 291357, characterized in that, in order to reduce the time of entry into synchronism, the error indicator is introduced into it, while the additional outputs of the phase discriminator are connected to the additional control input of the pulse frequency divider through the error indicator, the output of the distributor, and another output of the error indicator is connected to the auxiliary input of the control unit of the pulse frequency divider. 2. The device according to claim 1 ,. characterized in that the error indicator contains two triggers, the unit outputs of which are connected to the respective combined inputs of the exclusive OR element and the AND element, the control input of which is connected to the input of the differentiating circuit, the output of which is connected to the zero inputs of two triggers, and the same inputs of two triggers and the control input of the AND element are the inputs of the error indicator, and the outputs of the AND element and the exclusive or OR, respectively, outputs of the error indicator.