JPS62265829A - Stuff synchronizing system - Google Patents

Abstract

PURPOSE:To send remarkably information such as a supervisory system data at the same sending speed by supplying a clock of a low-order group n-channel to a multiplex section form the same clock generator as the high-order multiplex section. CONSTITUTION:Low-order multiplex sections 1, 2-n use the clock supplied from the same clock geenerator 10. Since the low-order multiplex sections 1, 2-n are synchronized, the phase of the clock of the high-order multiplex section 12 is compared with only the clock of a low-order multiplex section as a representative and a stuff pulse is inserted simultaneously in the stuff time slot of all the low-order multiplex sections. Thus, one channel is enough for the stuff control signal time slot and the time slots for (n-1)-channel are excessive, then information such as data for the supervisory system is contained to send to the time slots and sent, and the sent quantity of information is increased even at the same transmission speed.

Description

[Detailed Description of the Invention] [Summary] When multiplexing data from the n-channel multiplexing unit of the lower group using the stuff synchronization method in the upper multiplexing unit, the data from the n-channel multiplexing unit of the lower group By supplying clocks to the multiplexing sections from the same clock generator, it is possible to send a large amount of information such as monitoring system data even at the same transmission speed.

[Industrial application field]

The present invention relates to an improvement of a stuff synchronization method in which data from an n-channel multiplexer in a lower group is multiplexed in an upper multiplexer using the Skunov υ1 method.

One example in which the invention is desired is described below.

In the example of the multiplexer M L 3 used in North America, the data from the n lower group multiplexers M12 are multiplexed in the upper multiplexer M23 using the stuff synchronization method. However, monitoring data is sent to the other party via a different line.

If this multiplexer M13 is applied to an optical communication system, the repeating interval can be made long, but if this is done over a long distance, monitoring data will suffer a lot of loss and cannot be transmitted because the transmission path is not an optical fiber. .

In such a case, it is possible to adapt to the optical communication system by not transmitting the monitoring data through the side transfer path and by also transmitting the monitoring data using this device without changing the transmission speed of the multiplexer M13. desired.

[Conventional technology]

FIG. 4 is a block diagram of a conventional example, FIG. 5 is a time chart of a clock from an upper multiplexing unit in the stuff synchronization method, and FIG. 6 shows an example of a frame format in the case of FIG.

In the figure, 1.2.3 is a lower multiplexing section, 13.14.15 is a memory, 16, 17.18 is a phase comparator, and 12.0 is an upper multiplexing section.

The lower multiplexing section will be explained below taking as an example a case where there are three channels.

Usually, the clock speeds of the lower multiplexing units 1, 2.3 are slightly different. Therefore, the same 1υI stuff is performed for each multiplexer.

This stuff synchronization will be explained using the multiplexer 1 as a representative example.

The data from the multiplexer 1 is written into the memory 13 using the clock from the multiplexer 1.

On the other hand, the clock from the multiplexer 1 is input to the phase comparator 16, and the multiplexer 1 shown in FIG.
2' is compared, and when the phase difference reaches a predetermined value, the stuff control signal is used to synchronize the clock shown in FIG. Stuff synchronization is performed by reading data from the memory 13 using this clock.

This is shown in a frame format as shown in Figure 6, with frame bits l? Then channels 1, 2.3
The data of 1 are arranged one after another in order, and a stuffing control signal time slot of 2.3 is provided at a predetermined position indicated by a channel 1, into which a signal of, for example, 1 or 0 is input depending on whether or not stuffing is to be performed. If stuffing is to be performed at the predetermined position shown in C, for example, 1 is inserted, and if stuffing is not to be performed, a stuffing time slot is provided for inserting data. For example, if stuffing is to be performed at channel 1, Since the clock shown in is thinned out and no data is read out, insert 1 in the position of the first time slot C1,
Insert stuff pulse 1 into position 1 of time slot C.

Stuffing as shown below is performed between the multiplexing section 1.2.3 and the multiplexing section 12 to synchronize and perform multiplexing.

(Problem to be Solved by the Invention) However, in the above-mentioned stuff synchronization method, the number of stuff control 11 signal time slots is equal to the number of channels, and if the clock speed is constant, information such as monitoring system data etc. There is a problem that there are few villages to send them to.

[Means for solving problems]

As shown in the principle block diagram of FIG. When performing stuff synchronous multiplexing in the subgroup, the n-channel multiplexers 1, 2 . . . . A clock is supplied from the same clock generator 10 to the lower group, and the phase of the clock from the multiplexer of one channel of the lower group and the clock of the upper multiplexer 12 is compared, and Group n-channel multiplexer 1.2. This problem is solved by the stuffing synchronization method of the present invention, which stuffs n at the same time.

[Effect]

According to the present invention, lower multiplexing units 1, 2 . ...n is
Since the clocks supplied from the same clock generator 10 are used, and the lower multiplexing units 1, 2, . . . This is typically done using only the clock of one lower-order multiplexer, and the stuffing pulse can be inserted simultaneously into the stuffing time slots of all lower-order multiplexers, so the stuffing control signal time slot is Since only one channel is enough, and the time slot for n-1 channels is left over, information such as monitoring data can be sent here, and the amount of information sent can be increased at the same transmission speed. You can.

〔Example〕

FIG. 2 is a block diagram of an embodiment of the present invention, and FIG. 3 is an example of a frame format in the case of FIG.

In the figure, 10 indicates a clock generator, 12 indicates a higher-order multiplexing section, and throughout the drawing, the same reference numerals indicate the same functions.

The difference between FIG. 2 and FIG. 4 is that the lower multiplexing section is 2. 3 are supplied with a clock from one clock generator 10 and are synchronized, so the phase comparator 1G compares the clocks of the multiplexer 1 and the multiplexer 12. However, the stuffing is performed in both the multiplexing section and 2.3 at the same time.

The frame format in this case is as shown in Figure 3, and the stuffing time slot requires three channels, but the stuffing control signal time slot only requires one channel, as shown in C, and two Every time slot for two channels shown in is left over.

Therefore, since information such as monitoring system data can be sent in this part, it is possible to send more information at the same transmission speed.

〔Effect of the invention〕

As explained in detail above, according to the present invention, information can be sent even at the same transmission speed. It has the effect of increasing the number of 1s.

[Brief explanation of drawings]

Fig. 1 is a principle block diagram of the present invention, Fig. 2 is a block diagram of an embodiment of the present invention, and Fig. 3 is a block diagram of the principle of the present invention.
Figure 4 is a block diagram of the conventional example; Figure 5 is a time chart of the clock from the upper multiplexer in the multiplex system; Figure 6 is Figure 4. An example frame formant is shown in the case of . In the figure, 1.2.3...n is a lower multiplexing unit, 10 is a clock generator, 11 is a speed conversion unit, 12.12' is an upper multiplexing unit, 13.14.15 is a memory, 16.17.18 shows the phase comparator.

Claims (1)

[Claims] Subordinate group n-channel multiplexing unit (1, 2, . . . n)
When data is multiplexed by the upper multiplexing unit (12) using the stuff synchronization method via the speed conversion unit (11), the n-channel multiplexing unit (1, 2, . . .・・n
) is supplied from the same clock generator (10), and the phases of the clock from the multiplexing section of one channel of the lower group and the clock of the upper multiplexing section (12) are compared, A subgroup n-channel multiplexer (1,
2, . . . n) are simultaneously stuffed.