JPH0439930B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a synchronous switching system for digital lines, and in particular to a so-called 1:1 working protection digital line in which one protection line corresponds to one working line. Regarding synchronous switching method.

(Prior Art) Conventionally, this type of 1:1 working/standby digital line synchronous switching system has been used to improve the reliability of the entire system, and is composed of a transmitter 3 and a receiver 4 as shown in FIG. has been done. The transmitting section 3 includes branch circuits (hybrid) 30, 33, data processing sections 31, 32, transmitters 34, 35, a control section 36, and a switch 37.
is composed of receivers 41 and 42, a control section 43, and a switch 44. In such a configuration, an input signal supplied to the input terminal INPUT0 is branched into two for a working line and a protection line by a branch circuit 30, and is supplied to data processing units 31 and 32, respectively. The data processing units 31 and 32 convert bipolar signals used on the multiplexer side into unipolar signals used for code processing on the transmitter side, perform speed conversion of codes, and convert bits and bits for monitoring wireless or wired lines. Insert frame period bit. The digital signal into which such bits have been inserted is selected by a switch 37, passes through a branch circuit 33, is modulated by transmitters 34 and 35, and is sent in parallel to the receiver 4 through transmission lines 101 and 102, which are wireless or wired lines. sent to. Control circuit 36
detects the presence or absence of digital output signals from the data processing sections 31, 32, that is, a failure of the circuits 31, 32, and controls the switch 37 to select a normal circuit (line).

On the other hand, in the receiving section 4, the modulated waves from the transmission paths 101 and 102 are demodulated into digital signals received by the receivers 41 and 42, respectively. The control unit 43 controls the switch 44 to select, for example, the signal with a larger S/N ratio or the signal with a larger electrolytic strength among the output signals of the receivers 41 and 42.

(Problem to be solved by the invention) In such a conventional method, since one signal is transmitted in parallel, the reliability of the entire system can certainly be increased, but in order to transmit one signal, This method has the disadvantage that the efficiency of using the transmission path is low because it uses two transmission paths exclusively, and it also has the disadvantage that it takes twice as much transmission time to transmit two signals.

(Means for Solving the Problems) The 1:1 working/standby digital line synchronous switching system of the present invention eliminates the above-mentioned drawbacks and effectively transmits not only one signal but also two signals. The transmitter includes a transmitting section and a receiving section each having a spare function, and the transmitting section includes a first branch circuit that branches a first input signal, and a first data branch circuit that branches a first input signal, and a first branch circuit that branches a first input signal, and a first data branch circuit that receives an output signal of one of the first branch circuits. a processing circuit, a first switch that selects either a second input signal or the other output signal of the first branch circuit, and a second data processing device that receives the output of the first switch. a second and third data processing circuit connected to the outputs of the first and second data processing circuits, respectively;
a second switch for selecting either one of the outputs of the second branch circuit or the other output of the third branch circuit; and the other output of the second branch circuit. or a third branch circuit that selects one of the outputs of the third branch circuit;
switch, and first and second transmitters that transmit the outputs of the second and third switches to first and second transmission paths, respectively, and the receiving section includes a a fourth switch connected to the output of the second receiver, and a fourth switch connected to the output of the first receiver or the fourth receiver; and a fifth switch that selects one of the outputs of the switch and outputs it to the first output terminal, and the first input signal is transmitted in a 1:1 working protection line synchronous switching method. controls the first switch to supply the first input signal to the first and second data processing circuits, and supplies the output of either the second or third branch circuit to the first input signal. the second and third switches so as to supply outputs to the first and second transmitters, and to extract either of the outputs of the first and second receivers only from the first output terminal; and when transmitting the first and second input signals via the first and second transmission paths, respectively, the first input signal is the second input signal is output from the first output terminal via a first data processing circuit, a first transmitter, a first transmission path and a first receiver; The first to fifth It is characterized by controlling the switch.

(Example) Hereinafter, the present invention will be explained in more detail with reference to Examples.

FIG. 1 is a block diagram showing an embodiment of the 1:1 working/protection digital line synchronous switching system of the present invention, and this embodiment is composed of a transmitter 1 and a receiver 2. As shown in FIG.

The transmitter 1 includes a branch circuit (hybrid) 10,
13, 14, data processing units 11, 12, transmitter 1
5, 16, control unit 17 and switches 18 to 20
The receiving section 2 is composed of receivers 21 and 2.
2, a control section 23, and switches 24 and 25.

In such a configuration, when transmitting one signal, switches 18 to 20, 24 are used to transmit a parallel signal in order to increase the reliability of the entire system.
and 25. That is, the input terminal
When transmitting only the input signal supplied to INPUT 1, switches 18 and 25 are set to the a side. The input signal is branched into two by the branch circuit 10, one is directly supplied to the data processing section 11, and the other is supplied to the switch 1.
8 to the data processing unit 12. Switches 19 and 20 are controlled by control section 17 and supply one output of data processing sections 11 and 12 to transmitters 15 and 16. For example, if the data processing section 11 is normal and the data processing section 12 is abnormal (faulty), switches 19 and 20 are both switched to the a side, and the output of the data processing section 11 is transferred to the branch circuit 13 and switches 19 and 20. The modulated waves are supplied to transmitters 15 and 16 via transmission lines 101 and 102 and transmitted in parallel.

Furthermore, in the receiving section 2, these modulated waves are transmitted to the receiver 2.
1 and 22 for reception and demodulation. The control unit 23 controls the switch 24 to monitor the reception status at the receivers 21 and 22 and select a good line, and outputs the output terminal.
Take out the signal from OUTPUT1. In this way, when transmitting one signal, parallel transmission, that is, a 1:1 working/standby switching system is configured.

Next, when transmitting two input signals from input terminals INPUT 1 and 2, switches 18 to 20, 24 and 25 are controlled to transmit these input signals independently through transmission lines 101 and 102, respectively. do.

In other words, the switch 18 is placed on the b side, and the switch 1 is placed on the b side.
9 is on the a side, switch 20 is on the b side, switch 2
4 is controlled to be on the a side, and switch 25 is controlled to be on the b side. Therefore, the input signal of the input terminal INPUT1 is the circuit 10 → 11 → 13 → 19 → 15 → 101
→21→24 and is taken out from OUTPUT1. In addition, the input signal of INPUT2 is the circuit 18 →
It is taken out from OUTPUT 2 through 12 → 14 → 20 → 16 → 102 → 22 → 25. By doing so, the reliability of the system is low, but the efficiency of using the transmission path can be increased.

(Effect of the invention) As explained above, according to the method of the present invention,
In addition to the conventional 1:1 active/standby switching function, it also has the function of independently transmitting two input signals, which has the effect of increasing system utilization efficiency.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the 1:1 working protection digital line synchronous switching system of the present invention, and FIG. 2 is a block diagram showing an example of the conventional 1:1 working protection digital line synchronous switching system. . 1, 3... transmitter, 2, 4... receiver, 10,
13, 14, 30, 33... branch circuit, 11, 1
2, 31, 32...data processing section, 15, 16,
34, 35...Transmitter, 17, 23, 36, 43
...Control unit, 18, 19, 20, 24, 25, 3
7, 44...Switch, 21, 22, 41, 42
... Receiver, 101, 102 ... Transmission line.

Claims (1)

[Claims] 1. In a 1:1 working/protection digital line synchronous switching system including a transmitting section and a receiving section each having a working/standby function, the transmitting section transfers a first input signal to first and second input signals.
a first branch circuit that branches to an input branch signal; a first data processing circuit that receives the first input branch signal; and either the second input signal or the second input branch signal. a first switch that selects the first switch; and a second switch that receives the output of the first switch.
a data processing circuit, second and third branch circuits connected to outputs of the first and second data processing circuits, respectively, and a first output or a third branch circuit of the second branch circuit. a second switch for selecting one of the second outputs of the second output;
a third switch that selects either the second output of the branch circuit or the first output of the third branch circuit; the receiver includes first and second transmitters that respectively transmit signals to two transmission paths, and the receiving section includes first and second receivers that receive signals from the first and second transmission paths, respectively;
A fourth switch connected to the output of the second receiver selects either the output of the first receiver or the output of the fourth switch and connects it to the first output terminal. and a fifth switch for outputting, when transmitting the first input signal in a 1:1 working protection line synchronous switching method, the first input signal is transmitted to the first and second data processing circuits. the second and third switches to supply the outputs of either of the second and third branch circuits to the first and second transmitters; and controlling the fourth and fifth switches so as to take out either of the outputs of the first and second receivers only from the first output terminal; and When transmitting input signals via the first and second transmission paths, respectively, the first input signal is transmitted from the first data processing circuit,
so as to be taken out from the first output terminal via a first transmitter, a first transmission path and a first receiver,
and the second input signal is connected to a second input signal connected to the output of the fourth switch via the second data processing circuit, a second transmitter, a second transmission line and a second receiver. The first
A 1:1 working/protection digital line synchronous switching system characterized by controlling the first to fifth switches.