JPH0748718B2 - (1 + N) line switching device - Google Patents

Description

The present invention relates to a (1 + N) line switching device used at the receiving end of a (1 + N) line switching system.

(Prior Art) As is well known, in wireless communication, a protection line is provided to ensure constant communication even if the line quality deteriorates due to fading or the like, but in digital wireless communication, a line without causing a 1-bit error occurs. Is switched for each line (1+
N) Hitless line switching systems are being adopted.

As a (1 + N) hitless line switching system of this type, the one shown in FIG. 2 is conventionally known. In FIG. 2A, in the device on the sending end side, the N sending end switching circuits (11-1 to 11-N) have control signals (D _{1 to DN} ) from the sending end line switching control circuit 17. The corresponding one of the M input signal trains (201-1 to 201-N) is usually the corresponding one of the multiplexing circuits (12-1 to 12-N). And the pilot signal output from the pilot signal generation circuit 16 is controlled to be transmitted to the standby multiplexing circuit 12-0. Then, at the time of line failure or the like, when the control signal corresponding to the failed line, for example, the control signal D ₁ is output for parallel operation of the sending end, the sending end switching circuit 11-1 causes the multiplexing circuit 12-0. Is controlled so as to switch the input of the pilot signal from the pilot signal to the M-column input signal sequence 201-1.

On the other hand, in FIG. 2B, in the receiving end side device, (1+
N) line monitoring circuit (13) corresponding to the multiplexed signal of each line
-0,13-1 to 13-N) through the corresponding separation circuit (14-0,14
-1 to 14-N). Separation circuit (14-0,14-1 to 14-
N) removes the additional bits inserted in the wireless section from the multiplexed signal, performs code conversion or the like to restore the input signal sequence of M columns in the corresponding line, and outputs it. The output of the isolation circuit 14-0 of the standby system is input to the pilot signal detection circuit 18 and also one of the N hitless switching circuits (15-1 to 15-N). In addition, the separation circuit (14-1 ~
The output signal sequence (203-1 to 203-N) of M columns which is the output of 14-N) becomes the other input of the corresponding ones of the N hitless switching circuits (15-1 to 15-N).

Hitless switching circuits (151 to 15-N), which is corresponding ones individually switching control of the switching signal from the receiving end line switching control circuit 19 (E ₁ ~E _N), usually other Select and output the input. When no line failure or the like occurs, the pilot signal is transmitted to the protection line, so that the separation circuit
The output of 14-0 is a pilot signal. When the input signal is a pilot signal, the pilot signal detection circuit 18 sets the usage state signal C of the protection line to "available" and notifies the receiving end line switching control circuit 19 of it.

The receiving end line switching control circuit 19 is a working line monitoring circuit (13
-1~13-N) fault signal from (A ₁ ~A _N), and the standby system receives the fault signal B from the line monitoring circuit 13-0 of work as follows: the switching signal (E ₁ ~ Any one of E _N ) causes the corresponding one of the hitless switching circuits (15-1 to 15-N) to select one input.

For example, when the line monitoring circuit 13-1 detects a fault on the working line and outputs the fault signal A ₁ , the receiving end line switching control circuit 19 checks the fault signal B for the fault on the protection line, and The use state of the protection line is confirmed by the content of the use state signal C. As a result, if the backup line is available, the receiving line switching control circuit 19 then notifies the sending line switching control circuit 17 on the sending side that "the number of the line is faulty". To cause the sending end switching circuit 11-1 on the sending end side to start the sending end parallel operation. Then, the receiving end line switching control circuit 19 can confirm that the sending end parallel operation is correctly performed according to the content of the use state signal C and that the pilot signal does not exist in the protection line, that is, the completion of the sending end parallel operation can be confirmed. Compares both input signals (that is, the protection line signal 204 and the output signal sequence 203-1) of the hitless switching circuit, and after the bit and phase match is confirmed, the hitless switching circuit 15-1 is activated by the switching signal E ₁ . Switch to the protection line side.
This completes the relief of the faulty line.

As described above, in the conventional receiving-end-side device, like the sending-end-side device, line-by-line units, that is, all the signal trains of M columns are switched at the same time. The separation circuit (14-1 to 14-
If a failure occurs in some of the various devices in the process of restoring the M-sequence signal train in N), the receiver circuit is switched by receiving one fault signal (not shown) from the corresponding separation circuit. The control circuit 19 switches all the signal trains of the M-rows simultaneously with the completion of the sending end parallel operation for the purpose of quick line relief.

(Problems to be Solved by the Invention) However, in the case of a partial failure of a component device of the separation circuit,
There should be a signal train with no faults. Therefore, in the conventional method that switches all at the same time when the sending end parallel operation is completed without checking the matching of the bit and the phase, a momentary interruption occurs in the signal sequence in which no failure has occurred, and vice versa. There is a problem that a line failure occurs.

It is obvious that even in a system that does not require hitless switching, that is, a system that allows line switching accompanied by a hit, a switching method that affects other sound signal sequences is not preferable.

The present invention has been made in view of such a problem, and an object thereof is to provide, when a failure occurs in a part of a component device of a circuit that forms a signal sequence of M rows from a multiplexed signal on a receiving end side,
An object of the present invention is to provide a (1 + N) line switching device capable of performing line switching only for the signal train.

(Means for Solving the Problems) In order to achieve the above object, the (1 + N) line switching device of the present invention has the following configuration.

That is, in the (1 + N) line switching device of the present invention, when a line failure or the like occurs in any one of the N working lines, the transmitting end side performs the transmitting end parallel operation and the other line and the other one. The same multiplexed signal is transmitted on the protection line (1
+ N) in the (1 + N) line switching device provided on the receiving end side in the line switching system; fault detecting means for detecting a device fault for each signal sequence separated into M columns in each of the N active reception systems; Receiving a fault signal from the fault detection means, causing the transmission end side to perform the sending end parallel operation for the corresponding line, and outputting a switching control signal for the corresponding signal train of the corresponding line. And a control means for performing the above; between the corresponding ones of the signal sequences separated into M columns in one spare reception system and the respective signal sequences separated into M columns in each of the N active reception systems. And a switching means for switching between the working / standby state according to the switching control signal.

(Operation) Next, the operation of the (1 + N) line switching device of the present invention configured as described above will be described.

In the present invention, switching means for switching the signal sequence of M columns in each of the N lines is provided for each signal sequence, and the failure of the component equipment of the circuit forming the signal sequence of M columns is detected from the multiplexed signal for each signal sequence. For example, when a device failure occurs in one signal string, the sending end side performs the sending end parallel operation for the corresponding line, and outputs the switching control signal for the corresponding signal string on the corresponding line to the switching means.

As a result, only the signal train in which the device failure has occurred is switched to the protection line, and other sound signal trains remain in the working line, without any adverse effect.

Here, the switching means may be either a hitless switching circuit or a switching circuit involving a hit.

Embodiment An embodiment of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 shows a (1 + N) line switching device according to an embodiment of the present invention. In FIG. 1, M = 2 is shown,
The same components as those in FIG. 2 are designated by the same reference numerals.

In FIG. 1, a separation circuit (1-0, 1-1 to 1-N)
Has a function of removing the additional bit inserted in the wireless section and returning it to the input signal M sequence (M = 2 in this embodiment) as in the conventional case. detecting equipment failure signal ((G1, G2), ( F 11, F 12)
To (F _N1 , F _N2 )) are sent to the receiving end line switching control circuit 3. The fault detection, each signal stream from the multiplexed signal to be input to the alarm signal emitted by each component device in the process of restoring the ((Y1, Y2), ( X 11, X 12) ~ (X N1, X N2)) It is based on. The active and standby reception systems mean this separation circuit.

Two sets of switching circuits (2-1 to 2-N) are provided for each line, and switching control signals ((H ₁₁ , H ₁₂ ) to (H _N1 , H _N2 from the receiving end line switching control circuit are provided. )) Can be switched for each signal sequence. In addition, this switching circuit,
Although a hit may be involved, a hitless switching circuit will be described in the present embodiment in consideration of matching with the conventional device shown in FIG.

In the receiving end line switching control circuit 3, for example, the separation circuit 1-1
When the equipment failure signal F ₁₁ is input from the device, the presence or absence of the failure of the protection line is checked by the contents of the equipment failure signals G1 and G2, the usage status of the protection line is confirmed by the usage status signal C, and the protection line can be used. In this case, the sending end side is caused to perform the sending end parallel operation by the same procedure as in the conventional case, and the completion is confirmed by the use state signal C. The contents of the protection line signal sequence (Y1, Y2) is a signal sequence (X _11, X _12).

Next, when this confirmation is completed, the receiving end line switching control circuit 3
Sends a switching control signal H ₁₁ to the switching circuit 2-1 to switch only the column in which the failure has occurred.

As a result, the faulty signal train X ₁₁ is taken out from the protection line, and the healthy signal train X ₁₂ is taken out from the working line and is not affected by the switching.

It should be noted that the above description is for a case where no line failure has occurred, and the line failure is the same as the conventional one.
That is, in the receiving end line switching control circuit 3, the line monitoring circuit (13
(Line) fault signal from (-1 to 13-N, 13-0) (A _{1 to} A _N , B)
In response to this, the sending end side is caused to perform the sending end parallel operation in the same procedure as in the conventional case. For example, when it is based on the (line) fault signal A ₁ , the switching circuit 2-1 (in this embodiment, bit and phase After the confirmation of the coincidence, the switching control signals H ₁₁ and H ₁₂ are simultaneously output to switch the entire line (hitlessly).

(Effects of the Invention) As described above, according to the (1 + N) line switching device of the present invention, switching means for switching the signal sequence of M columns in each of the N lines is provided for each signal sequence, and from the multiplexed signal to M Detecting a failure of a component device of a circuit forming a signal train for each signal train, for example, when a device trouble occurs in one signal train, the sending end side performs a sending end parallel operation for the corresponding line,
Further, since the switching control signal for the corresponding signal train on the corresponding line is output to the switching means, it is possible to switch only the signal train in which the device failure has occurred without affecting other signal trains. There is an effect that it is possible to provide a line switching device that can be relieved.

[Brief description of drawings]

FIG. 1 is a configuration block diagram of a (1 + N) line switching device according to an embodiment of the present invention, and FIG. 2 is a configuration block diagram of a conventional (1 + N) hitless line switching system. 1-0, 1-1 to 1-N ... Separation circuit, 2-1 to 2-N
...... Switching circuit, 3 …… Reception line switching control circuit.

Claims (1)

[Claims] 1. When a line fault or the like occurs in any one of the N working lines, the sending end performs a sending end parallel operation and the same multiplexing is performed for the line and another spare line. In the (1 + N) line switching device provided on the receiving end side in the (1 + N) line switching system adapted to transmit the standardized signal; equipment failure for each signal sequence separated into M columns in each of the N active reception systems A fault detecting means for detecting a fault signal; receiving a fault signal from the fault detecting means, causing the transmitting side to perform the transmitting end parallel operation for the corresponding line, and a corresponding signal for the corresponding line. Control means for outputting a switching control signal for each column; each signal column separated into M columns in one spare reception system and each signal separated into M columns in each of the N active reception systems Correspondence between columns (1 + N) line switching device, comprising: switching means for switching between working / standby according to the switching control signal.