JPH0541678A - Inter-transmitter signal path changeover system - Google Patents

Abstract

PURPOSE:To shorten the signal cut-off time at the time of the signal path changeover between transfer devices as short as possible in the inter-transmitter signal path changeover system with two-system path selection part and a two- system intra-device signal selection part in the transmitter among two systems of the signal paths between transmitters. CONSTITUTION:The system is provided with changeover control means S1 and S2 performing the line changeover control of a device second-system path selection part, changeover parts S2 and S4 switching the intra-device operation system from the first to the second system at the intra-device signal selection part, changeover control means S5 and S6 performing the line changeover control of the intra-device first-system line selection part, and a changeover means S7 and S8 switching the intra-device operation system from the second to the first system in the intra-device signal selection part. Thus, a signal passing one of the signal path is switched to pass the other signal path.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a signal path switching system between transmission devices, and in particular, there are two signal paths between transmission devices.
The present invention relates to a signal path switching system between transmission devices of a transmission device having a two-system route selection unit and a two-system signal selection unit in the transmission device.

[0002]

2. Description of the Related Art Conventionally, switching of signal paths between transmission devices is performed when it is necessary to change the signal paths due to maintenance of devices on a transmission medium such as an optical cable and a transmission medium such as a repeater. In this case, it is performed using a cross-connect device or the like that internally switches the paths between the plurality of input signals and the plurality of output signals. The cross-connect device has a redundant configuration to improve reliability.
That is, there are two system signal paths in the cross-connect device, and the same signal is usually passed through the two system signal paths so that they can be selected alternatively.

For example, a cross-connect device uses a circuit having a structure as shown in FIG. In FIG. 4 showing a circuit example of this cross-connect device, an input signal is branched into two system signals in the device by the in-device branching units 11, 12, ... 1N-1, 1N, and the route selecting unit 2 , 3 is input.
Here, the path selection unit has a function of selectively connecting any one of the N input groups to any one of the N output groups. Normally, the route selection unit 2 and the route selection unit 3 are connected to each other. As a result, the route-selected signals of the two systems are connected to the route in the in-device signal selectors 41, 42 ...
・ Input to 4N-1 and 4N. Here, the signal is alternatively selected and output to the path. A method of switching a signal path between transmission devices using such a cross-connect device will be considered.

FIG. 5 shows the overall configuration of signal path switching between transmission devices. In FIG. 5, the devices A and B are cross-connect devices, and the relay transmission line of the route X is connected to the atx end of the device A and the brx end of the device B, and the aty end of the device A and the bry end of the device B are connected. It is assumed that the relay transmission line of the route Y is connected to the. Now, it is assumed that a signal is input from the transmission line connected to the ar1 end of the device A and is output to the transmission line connected to the bt1 end of the device B through the relay transmission line of the route X.

FIG. 6 shows the cross-connect state of the devices A and B at this time. After that, it is assumed that the relay transmission path through which the signal passes is switched from the path X to the path Y. FIG. 6 is a circuit diagram showing a cross-connect state before switching.

Conventionally, this kind of signal path switching between transmission devices has been performed by the method shown in FIG. 7 which is a flowchart showing the conventional switching operation. That is, first,
Switching control of the path of the device A2 (SA ₁ ) is performed, and then switching control of the device A3 (SA ₂ ) is performed. At the same time, device B
The switching control (SB ₁ ) of the route 2 is performed, and then the switching control (SB ₂ ) of the route of the device B3 is performed. In this FIG.
A2 is a transmission side device first system route selection unit, A3 is a transmission side device second system route selection unit, A4X is a transmission side device signal selection unit (switching source), and A4Y is a transmission side device signal selection unit (switching destination). ), B2 is a receiving side device first system route selecting unit, B2
Reference numeral 3 indicates a receiving-side device second system route selecting unit, and B41 indicates a receiving-side device internal signal selecting unit. Then, each step SA ₁ , S
As described above, A ₂ , SB ₁ and SB ₂ execute predetermined processing.

The cross-connect state at this time is shown in FIG. FIG. 8 is a circuit diagram showing a conventional cross-connect state transition.

[0008]

In the above-mentioned conventional method for switching the route of the signal path in operation, the device A2 is used.
The instantaneous interruption time of the signal at the time of switching the route in B2 is set in the devices A2 and B2.
There is a problem that it is long due to the characteristics of
There was a problem that there is a signal disconnection time due to the deviation of the control time of 2.

[0009]

According to the signal path switching method between transmission devices of the present invention, there are two signal paths between transmission devices,
There are two system path selection units for selecting one of the two system signal paths, and an in-device signal selection unit for selecting one of the signals of the two system system path and connecting the signal paths. In the inter-transmission-device signal path switching method using a transmission device provided for each signal path, the first switching control means for performing line switching control of the in-device second system path selection unit and the in-device signal selection unit First switching means for switching the operating system from the first system to the second system, second switching control means for performing route switching control of the in-device first system route selection section, and in-device operation by the in-device signal selection section A second switching means for switching the system from the second system to the first system is provided, and the signal path is switched so that the signal passing through one of the signal paths passes through the other signal path.

[0010]

In the present invention, when the signal path between the transmission devices is switched, first, the path switching control of the second system in the device is performed, and then the operation system switching control from the first system to the second system is performed. , Further, the route switching control of the first system is performed, and finally the operation system switching control from the second system to the first system is performed, so that the route selectors of the two systems select different routes and perform the system switching. ..

[0011]

FIG. 1 is a flow chart showing an operation procedure of an embodiment of a signal path switching system between transmission devices according to the present invention, which uses the cross-connect device shown in FIG. 4 and has the configuration shown in FIG. It is an example applied to the switching of the signal path between them. Then, each executing a predetermined processing in each step S ₁ to S _8.

In FIG. 1, steps S ₁ and S ₂ constitute switching control means for controlling the route switching of the second system route selecting section in the apparatus, and steps S ₃ and S ₄ are signal selecting sections in the apparatus. It constitutes a switching means for switching the internal operation system from the first system to the second system. Further, steps S ₅ and S ₆ constitute a switching control means for performing the path switching control of the in-device first system route selection unit, and steps S ₇ and S ₈ are the in-device signal selection unit to set the in-device operation system to the second system. The switching means is configured to switch from the system to the first system. Further, by having each of these means, the signal path is switched so that the signal passing through one of the signal paths passes through the other signal path.

Next, the operation of the embodiment shown in FIG. 1 will be described. First, the cross-connect device has two route selection units as shown in FIG. 4 in order to improve the reliability inside the device, but conventionally, the same route was always selected in conjunction with each other. INDUSTRIAL APPLICABILITY The present invention makes it possible to shorten the signal disconnection time as much as possible by separately controlling the two systems of route selectors when switching the signal route between devices.
In FIG. 5, which shows the overall configuration of the signal path switching between the transmission devices, a signal is input from the transmission line connected to the ar1 end of the device A and is connected to the bt1 end of the device B through the relay transmission line of the route X. It is assumed that the signal is output to the transmission line. FIG. 6 shows the cross-connection state of the devices A and B at this time. After that, a control method will be described in which it is possible to shorten the signal disconnection as much as possible when switching the passing relay transmission path from the path X to the path Y.

As shown in FIG. 1, first, the route switching control (step S ₁ ) of the device A3 (transmission side device second system route selection unit) is performed, and then the device B3 (reception side device second system route). The route switching control (step S ₂ ) of the selection unit) is performed,
Then, by the apparatus A4Y (transmitting device in the signal selection section) (switching destination) performs operational system switching control from the first system to the second system (Step S _3), further device B41 (receiving device in the signal selection the section), by performing the operation system switching control from the first system to the second system (step S _4), the state shown in FIG. 2 is a circuit diagram showing a state transition of the cross-connect of the present invention. After that, the route switching control (step S ₅ ) of the (transmission-side device first system route selection unit) of the device A2 is performed.
Path switching control unit B2 (reception side apparatus the first system path selection unit) (Step S ₆₎ performed, and, the operation system from the second system by the apparatus A4Y (transmitting device in the signal selecting section) to the first system Switching control (step S ₇ ) is performed, and the device B
1 (from the second system to the first by 41 (internal device signal selection section))
FIG. 3 is a circuit diagram showing the state transition of the cross-connect of the present invention when the operation system switching control (step S ₈ ) to the system is performed.
The state shown in FIG.

[0015]

As described above, according to the present invention, in the case of switching the signal paths between the transmission devices by using the route selection units of two systems, which have conventionally always selected the same route in conjunction with each other, first of all, The second system path switching control is performed, and then the first system
System switching control from the second system to the second system is performed, the route switching control of the first system is further performed, and finally the system switching control from the second system to the first system is performed. Since the selection unit selects different paths to switch the system, the signal disconnection on the output transmission line can be done only when the system is switched, and the switching time of the system switching unit is short so that the signal disconnection time can be minimized. It has the effect that it can be shortened.

[Brief description of drawings]

FIG. 1 is a flowchart showing an operation procedure of an embodiment of a signal path switching system between transmission devices according to the present invention.

FIG. 2 is a circuit diagram showing a state transition of a cross connect of the present invention.

FIG. 3 is a circuit diagram showing a state transition of a cross connect of the present invention.

FIG. 4 is a circuit diagram showing a circuit example of a cross-connect device.

FIG. 5 is a block diagram showing an overall configuration of signal path switching between transmission devices.

FIG. 6 is a circuit diagram showing a cross-connect state before switching.

FIG. 7 is a flowchart showing a conventional switching operation.

FIG. 8 is a circuit diagram showing a state transition of a conventional cross connect.

[Explanation of symbols]

 A2 transmission side device first system route selection unit A3 transmission side device second system route selection unit A4X transmission side device internal signal selection unit (switching source) A4Y transmission side device internal signal selection unit (switching destination) B2 reception side device first System route selection unit B3 Receiving side device Second system route selecting unit B41 Receiving side device signal selection unit

Claims (1)

[Claims] 1. There are two signal paths between transmission devices, and two path selection sections for selecting one of these two signal paths are provided, and one of the signals of these two path selection sections is selected. In the inter-transmission-device signal path switching method using a transmission device having an in-device signal selection unit for connecting the signal paths for each signal route, line switching control of the in-device second system route selection unit is performed. A first switching control means, a first switching means for switching an in-device operating system from a first system to a second system by an in-device signal selection section, and a route switching control of an in-device first system route selection section; 2 switching control means and second switching means for switching the in-device operating system from the second system to the first system by the in-device signal selection section, and a signal passing through one of the signal paths is connected to the other signal path. Switching the signal path through A signal path switching method between transmission devices characterized by.