JPH06177799A - Line switching system for transmitter - Google Patents

Abstract

PURPOSE:To prevent excess wiring and signal reflection by sending an input signal to a reserve terminal through a 2nd switch group constructed in the tournament system to a reserve transmission/reception section when a fault occurs in an active transmission or reception section. CONSTITUTION:When a fault occurs, for example, in a transmission/reception section 100-1 from among active transmission/reception sections 100-1 to 100-n, an active terminal for a 1st switch group corresponding to the transmission/reception section 100-1 is switched to the reserve terminal. An input signal applied to the reserve terminal is sent to the reserve transmission/ reception section 100-p through a 2:1 switch 500 of a 2nd switch group and a 2:1 switch 500 of the final stage constructed in the tournament system. Thus, excess wiring is eliminated and time release end of the switch 500 is not connected to the reserve transmission/reception section 100-p, resulting in preventing the reflection of signal due to the release end of the 2:1 switch 500.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a line switching system of a transmission device. The boards (packages) that make up the communication device are divided for each function, and each board has a redundant configuration with a backup system in order to improve the reliability of the device. And for a 1 + 1 redundant configuration with 1 spare board for 1 working board, 1 for multiple working boards
It is not uncommon for a 1: N redundant configuration with two spare boards to be used. In this case, there is a demand for a switching method that does not cause signal deterioration when switching from the current board to the spare board.

[0002]

2. Description of the Related Art FIG. 3 is a block diagram of a conventional switching control board. FIG. 3 shows the case of the transmitting device, but in the figure, the contacts 3-1 to 3-4 of the relays in which the signals of the low-order group input to the input terminals to of the switching control panel 2 are set to the a side are shown. Add to the current transmission board 1-1 to 1-4 via. And the transmission board 1-
After performing the predetermined processing in 1 to 1-4, each output is multiplexed by a multiplexer (not shown) connected in the subsequent stage and sent to the optical transmission line.

Now, if a failure occurs in the active transmission board 1-1, this is detected by a monitoring circuit (not shown) mounted on the switching control board 2 and relayed to a relay drive circuit (not shown). Outputs the switching command for contact 3-1. In the relay drive circuit (not shown), this switching command causes relay contact 3-1 to b side and relay contact 4-1 to d side, 4-
Switch 2 to 4-4 to the c side and add the signal input to the input terminal to the spare transmission board 1-p. In this way, the line is switched in response to the failure of the transmitting board.

Similarly, when a failure occurs in the current transmission panel 1-2, the relay contact 3-2 of the switching control panel 2 is switched to the b side and the relay contact 4-2 is switched to the d side. , Add the signal input to the input terminal to the spare transmitter board 1-p. The same shall apply when a failure occurs in the active transmission board 1-3 or 1-4.

Although the above-mentioned example is the case of the transmitting apparatus, similarly in the case of the receiving apparatus, the signal input from the optical transmission line to the demultiplexing apparatus (not shown) and demultiplexed is switched for reception. Add to receiving board (not shown) via control board (not shown).

[0006]

However, in the configuration of the circuit described above, the contacts 4-2 of the relay shown in FIG.
When the input signal becomes high speed (for example, 140 MHz) when the shaded area including 4-4 becomes extra wiring, these relay contacts
There was a problem that the signal was deteriorated by the reflection at the open end of 4-2 to 4-4 and the characteristic standard (international standard, CCITT, etc.) of the input / output section of the device could not be satisfied.

Therefore, it is an object of the present invention to provide a line switching system for a transmission device in which signal deterioration does not occur at the time of switching from the current board to the spare board.

[0008]

The above problems can be solved by the circuit configuration shown in FIG. That is, in FIG. 1, a plurality of active transmission / reception units (100-1 to 100-n) for transmitting or receiving an input signal, a backup transmission / reception unit 100-p, and a plurality of active transmissions. It has a plurality of working / spare terminals corresponding to the receiving section, and normally, an input signal is added to a plurality of working transmitting / receiving sections via the working terminals, respectively, and a plurality of working transmitting / receiving sections are added. When a failure occurs in any of the receiving sections, the working terminal corresponding to the working transmitting / receiving section in which the failure has occurred is switched to the spare terminal, and the input signal is transferred to the spare transmitting / receiving section via the spare terminal. In the line switching method of a transmission device having a switching control unit 200 having a first switch group to be added, a 2: 1 switch 500 for selecting and outputting one of two inputs is cascaded to the switching control unit 200. Connect multiple inputs to each of the 2: 1 switches 500 in the first stage. A second switch group is provided, which is connected to each spare terminal of the first switch group and applies the output of the final 2: 1 switch 500 to the spare transmission / reception unit 100-p.

[0009]

As shown in FIG. 1, the active transmitter / receiver (100-1
~ 100-n), for example, when a fault occurs in 100-1, the first corresponding to the faulty active transmitter / receiver 100-1
The active terminal of the switch group is switched to the spare terminal. Then, the input signal applied to the spare terminal is the 2: 1 switch 500 of the plurality of stages of the second switch group and the final 2: 1 switch 500 of the second switch group configured in the tournament system.
Is transferred to the spare transmission / reception unit 100-p via.

As a result, extra wiring is eliminated and the open end of the 2: 1 switch 500 is used as a spare transmission / reception unit 1.
Since it is not connected to 00-p, signal reflection due to extra wiring and the open end of the 2: 1 switch 500 can be prevented, and the characteristic standard can be satisfied.

[0011]

FIG. 2 is a block diagram of a switching control board according to an embodiment of the present invention. FIG. 2 shows the case of a transmitter, but in the figure,
Normally, as in the case of the conventional example, the low-order group signals input to the input terminals ~ of the switching control board 2'are respectively transmitted through the relay contacts 3-1 to 3-4 to the current transmission board 1-1. Add to 1-4. Then, after performing a predetermined process in the active transmission boards 1-1 to 1-4, the respective outputs are multiplexed by a multiplexer (not shown) connected in the subsequent stage and output to the optical transmission line.

Now, assuming that a failure occurs in the active transmission board 1-1, this is detected by a monitoring circuit (not shown) mounted on the switching control board 2 ', and a relay drive circuit (not shown) is detected. Relay contact 3-1, switching command of 5 and 7 is output, relay contact is made by relay drive circuit (not shown)
3-1 is switched to the b side, 5 is switched to the c side, and the contact 7 of the relay is switched to the e side, and the signal input to the input terminal is used as a spare transmission board 1-
Add to p.

As a result, in the structure of the present invention, since there is no extra wiring and the open end of the contact of the relay, there is no signal reflection and the characteristic standard can be satisfied. If the switching control panel 2'is pulled out from the connector of the device for any reason, the connection of the connector for supplying power to the relay contacts 3-1 to 3-4, 5, 6 and 7 will also be disconnected and the relay will be disconnected. No power is supplied to the contact of the relay, but when the contact of the relay is a non-holding type, the line is maintained as it is if no switching occurs. Further, when switching occurs and it is necessary to maintain the switching state as it is, the line can be maintained in the operating state by using the contact of the holding type relay.

It should be noted that these working and spare transmission boards 1-1 to 1-
4 and 1-p and the switching control panel 2'are connected with a cable with a margin, so even if the switching control panel 2'is removed from the equipment, these working and standby transmission panels 1-1 to 1-4
, 1-p and the switching control panel 2'are not interrupted.

[0015]

As described above, according to the present invention, when a failure occurs in any of the active transmission / reception units (100-1 to 100-n), the active transmission with the failure occurs. / The working terminal of the first switch group corresponding to the receiving unit is switched to the spare terminal. Then, the input signal applied to the spare terminal is transmitted / received as a backup through the 2: 1 switch 500 in the plurality of stages and the 2: 1 switch 500 in the final stage of the second switch group configured in the tournament method. Part 100-p.

As a result, extra wiring is eliminated, and the open end of the 2: 1 switch is the spare transmission / reception unit 100-.
Since it is not connected to p, signal reflection due to extra wiring and the open end of the 2: 1 switch can be prevented, and the characteristic standard can be satisfied.

[Brief description of drawings]

FIG. 1 is a principle diagram of the present invention,

FIG. 2 is a configuration diagram of a switching control panel according to an embodiment of the present invention,

FIG. 3 is a configuration diagram of a conventional switching control panel.

[Explanation of symbols]

Reference numerals 100-1 to 100-n are active transmission / reception units, 100-p are backup transmission / reception units, 200 is a switching control unit, and 500 is a 2: 1 switch.

Claims (1)

[Claims] 1. A plurality of active transmission / reception units (100-1 to 100-n) for transmitting or receiving an input signal, a spare transmission / reception unit (100-p), and a plurality of these transmission / reception units (100-p). It has a plurality of working and spare terminals corresponding to the working transmission / reception section, and normally applies an input signal to each of the plurality of working transmission / reception sections via the working terminal, When a failure occurs in any one of the working transmission / reception units, the working terminal corresponding to the working transmission / reception unit in which the failure has occurred is switched to the spare terminal to input the input signal to the spare terminal. In the line switching method of a transmission device having a switching control unit (200) including a first switch group added to the backup transmission / reception unit via the switching control unit (200), one of two inputs is provided. Multiple 2: 1 switches (500) that select input and output are connected in cascade to connect multiple 2: 1 switches in the first stage.
Each input of the switch (500) is connected to each spare terminal of the first switch group, and the output of the final stage 2: 1 switch (500) is added to the spare transmitter / receiver (100-p). A line switching system for a transmission device, characterized in that a second switch group is provided.