JPS62261240A - Active/standby switching system - Google Patents

Abstract

PURPOSE:To allow one set of standby equipment to cope with plural active equipments having different code forms by switching automatically the function of a decoder or a coder of the standby equipment so as to cope with the code form of a signal processed by the active equipment in switching the active equipment into the standby equipment. CONSTITUTION:Each of the active equipments 1a,1b,2a,2b and the standby equipments 3a, 3b is provided with the decoder 4 or the coder 5 having a code form set by setting information respectively. Further, each of the standby equipments 3a, 3b is provided with a selector selecting the different setting information and applying it to the decoder 4 or the coder 5. In connecting switchingly the active equipments 1a,1b to the standby equipments 3a, 3b by means of switching circuits 7a, 7b, the setting information to the active equipments 1a,1b is fed to the decoder 4 and the coder 5 of the standby equipments 3a, 3b via the selector 6. Thus, the standby equipments 3a, 3b apply the decoding/coding of the same code form as that of the active equipments 1a, 1b.

Description

[Detailed Description of the Invention] [Summary] When switching to a backup device due to a failure in the current device, “
It automatically switches the functions of the decoder or encoder in the standby device so that signal processing continues in a code format that corresponds to the code format of the signal being processed by the active device, and thereby, One standby device can handle multiple active devices that process signals of different code formats.

[Industrial application field]

The present invention relates to a working/standby switching system that allows communication to be continued by switching to a standby device in the event of a fault in the working device.

In wireless communication systems, since data is modulated and transmitted, the NRZ code is generally used because it has few high frequency components and is advantageous in terms of the required bandwidth. On the other hand, in the baseband transmission system, the AMI (Alternate
Mark Inversion) codes are used.

Furthermore, in a system where transmission information such as a series of "0"s is generated, it becomes difficult to extract the timing on the receiving side.

Therefore, as an “O” continuous suppression code, n bits of “0”
Convert continuous to special pattern B n Z S
(B 1polar with n ZerosS
ubsti tition) code is used.

HDB3 (High Density B) converts four continuous blocks of “0” into a special code pattern.
i-polar3) codes are also known.

Therefore, in the wireless transmitter/receiver section, NRZ for wireless communication
It is generally provided with a function of converting a code into an AMI code, BnZS code, HDB3 code, etc. for baseband transmission. In addition, in various systems, when there is a failure on the active side, the reliability of the system is improved by switching to the backup side and continuing processing such as communication. There is.

In the former system backup method, a backup system using another radio frequency is prepared in advance in addition to the current system.
In the event of a failure in the active system, the system switches to the backup system in a predetermined section.The latter set backup method prepares a backup device for each device that makes up the system, and switches to the backup system in the event of a failure. be.

In a wireless communication system using such a working/protection switching method, the code format for baseband transmission is generally unified. However, in order to use a code format that is optimal for the characteristics of the transmitted information, there are cases where a different code format is used for the current device. Even in such a wireless communication system, it is desired to be able to economically switch between working and standby.

[Conventional technology]

In wireless communication systems, as mentioned above, the code format on the baseband transmission side is unified to, for example, the AMI code, and in the wireless transmitter, the AMI code is converted into the NRZ code by a decoder. For example, the received signal is demodulated in the wireless receiving section, and the demodulated NRZ code is converted into an AMI code by an encoder. It will be converted to and sent to the line.

[Problem that the invention seeks to solve]

As described above, an AMI code in which pulses of positive polarity and pulses of negative polarity are alternately generated every time a "1" occurs is sufficient for transmission information in which a long period of "0" does not occur. However, for transmission information where “0” continues for a long period of time, the AMI
If only the code is used, the timing cannot be extracted on the receiving side, so when "O" is consecutively given for a predetermined number of bits n,
It is desirable to convert the bit "0" into a BnZS code that converts the bit into a special pattern including positive polarity pulses and negative polarity pulses. Therefore, even in wireless communication systems, current devices with different code formats are used.

In a wireless communication system where the code format is unified, as mentioned above, it is possible to provide one standby device for multiple working devices and apply the N:1 working/standby switching method. However, for a plurality of active devices with different code formats, unless a backup device is provided corresponding to the code format, it is not possible to switch between the active and backup devices, which has the disadvantage of increasing the system scale.

SUMMARY OF THE INVENTION An object of the present invention is to enable a single standby device to apply a working/standby switching method to a plurality of working devices with different code formats.

[Means for solving problems]

The active/backup switching method of the present invention constitutes a system by a working device and a backup device that are equipped with a decoder or encoder that can switch and set functions in accordance with the code format, and will be explained with reference to FIG. do.

Active device 1a+ lb, 2a, 2b and backup device 3a,
3b is provided with a decoder 4 or an encoder 5 that performs decoding or encoding of the code format set by the setting information, respectively, and the preliminary devices 3a and 3b are provided with a decoder 4 or an encoder 5 that performs decoding or encoding of the code format set according to the setting information, and the preparatory devices 3a and 3b are provided with a decoder 4 or an encoder 5 by selecting different setting information. Alternatively, a selector 6 added to the encoder 5 is provided.

When the current device fails, the switching circuit 7a is activated according to the switching signal.
, 7b, the current device is switched and connected to the backup devices 3a, 3b, and the setting information of the current device is added to the decoder 4 or encoder 5 of the backup device 3a, 3b via the selector 6, and is processed by the current device. A signal in the encoded format is applied from the hybrid circuit 8 to the backup device 3a via the switching circuit 7a, and is decoded and transmitted by the decoder 4 in the same encoding format as that of the current device, and is sent to the encoder 5 of the backup device 3b. The encoded signal is encoded in the same code format as that of the current device and sent from the switching circuit 7b via the hybrid circuit 8.

[Effect]

In the current devices 1a, lb, 2a, and 2b, the decoder 4 and encoder 5 perform decoding processing and encoding processing corresponding to the code format according to setting information.
a, lb to spare device 3a.

3b, the setting information for the active devices 1a and lb is added to the decoder 4 and encoder 5 of the backup devices 3a and 3b via the selector 6.
a and 3b are the current devices 1a.

It is possible to perform decoding and encoding in the same code format as 1b, and when the active devices 2a, 2b are switched and connected to the backup devices 3a, 3b, the setting information for the active devices 2a, 2b is transferred to the backup devices via the selector 6. Recaptor 4 of devices 3a, 3b
and encoder 5, and can perform decoding and encoding in the same code format as the current devices 2a and 2b.

〔Example〕

Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 2 is a block diagram of an embodiment of the present invention; 11.
12 is a working transmitting device; 13 is a backup transmitting device; 14 is a decoder that sets setting information (al, (bl) to determine whether to decode an AMI code to an NRZ code or a BnZS code to an NRZ code; 15 is a decoder a signal processing section; 16 a transmitting section that performs modulation processing such as multilevel QAM; 17 a switching circuit;
8.19 is a hybrid circuit, and 20 is a selector.

The bipolar signal A of the AMI code is transmitted to the hybrid circuit 18
When the bipolar signal B of the BnZS code is applied to the working transmitting device 12 via the hybrid circuit 19, the decoder 14 of the working transmitting device 11 uses the setting information +8). NR sign
The decoder 14 of the current transmitting device 12 decodes the BnZS code into NR
It is set to decode to Z code.

These setting information (al, (b)
Since the switching signal at this time switches the switching circuit 17 to the neutral position, the preliminary transmitting device 13 receives AM! The state is such that neither the bipolar signals A nor B of the BnZS code or the BnZS code are applied. Therefore, whether the selector 20 selectively outputs the setting information (a) or (b) or not, the operation of the backup transmitter 13 is not affected.

Also, the signal decoded into the N RZ code by the decoder 14 is
The signal is applied to the signal processing unit 15 as a unipolar signal, and the signal processing unit 15 performs processing such as serial-to-parallel conversion and adds the unipolar signal to the transmitting unit 16. The signal is modulated by QAM or the like and then transmitted.

When a failure occurs in the active transmitter 11, a control unit (not shown) detects the failure and sends a switching signal to the switching circuit 17 and selector 20 to switch and connect the backup transmitter 13 instead of the active transmitter 11. Added. As a result, the switching circuit 17 is switched and connected to the hybrid circuit 18 side, the bipolar signal A of the AMI code is added to the backup transmitter 13, and the setting information (al) for the active transmitter 11 is sent to the backup transmitter through the selector 20. 13, and the decoder 14 is set to have a function of decoding an AMI code into an NRZ code.Therefore, the backup transmitting device 13 can perform a transmitting operation in place of the active transmitting device 11.

If a failure occurs in the active transmitting device 12, the switching circuit 17 is switched to the hybrid circuit 19 side by the switching signal, and the bipolar signal B of the BnZS code is applied to the backup transmitting device 13, and the switching signal to the active transmitting device 12 is Since the setting information (b) is applied to the decoder 14 of the backup transmitter 13 via the selector 20, the decoder 14
The function is set to decode the code into an NRZ code. Therefore, the backup transmitter 'fl 13 can perform a transmitting operation in place of the active transmitter 12.

Although FIG. 2 only shows the transmitting side of the wireless communication system, the receiving side can also be configured accordingly, and the NRZ code can be encoded into an AMI code or a BnZS code depending on the setting information. The active receiving device and the standby receiving device are provided with an encoder for this purpose, and the setting information selected by the selector in response to the switching connection is added to the encoder in the standby receiving device.

FIG. 3 is a block diagram of another embodiment of the present invention, showing a working/standby switching system in which a switching circuit 27 connects a standby transmitter 24 to the working transmitters 21 to 23. For example, bipolar signal A of AMI code,
Bipolar signal B of the B8ZS code (a code that converts a block of 8 consecutive "0" bits into a special pattern bipolar signal due to bipolar violation) and B6
A bipolar signal C of the ZS code (a code that converts a block of 6 consecutive "O" bits into a bipolar signal with a special pattern due to bipolar violation) is added to the current transmitting devices 21 to 23 via the switching circuit 27, respectively. The decoder 25 of the active transmitting device 21 is configured to decode the AMI code to the NRZ code by the setting information (al, and the decoder 25 of the active transmitting device 22 is configured to decode the B8ZS code to the NRZ code by the setting information (bl). According to the setting information (C), the decoder 25 of the current transmitter 23 is set to decode the B6ZS code into an NRZ code.

Furthermore, when other active transmitting devices are provided and the decoder is configured using configuration information to decode in accordance with other code formats, the selector 26 of the backup transmitting device 24 contains settings for those active transmitting devices. Love I! ! (a) to fn) are added, the selector 26 is controlled by the switching signal that controls the switching circuit 27, and the setting information +al to in) is selectively outputted and added to the decoder 25. Therefore, even if there are multiple stages of active transmitters that transmit and process bipolar signals A, B, C, etc. of different code formats, and one standby transmitter 24 is provided for each of them, When the active transmitter is connected to the standby transmitter 24 by the switching circuit 27, the selector 27 selects the setting information (
Since the selections a) to (n) are made and the configuration information of the active transmitter is added to the decoder 25 of the backup transmitter, it is possible to continue the transmitting operation.

Like the embodiment shown in FIG. 2, the embodiment shown in FIG. 3 only shows the transmitting side of the wireless communication system, so the receiving side is also equipped with an encoder capable of encoding different code formats. It consists of:

FIG. 4 is a block diagram of a main part of an example of a decoder, and converts the above-mentioned AMI code, B8ZS code, and B6ZS code into NRZ
This shows a decoder with the function of decoding into codes.

The bipolar signal is separated into a positive polarity pulse PP and a negative polarity pulse MP by a circuit (not shown), which is applied to the conversion circuit 31, and is converted into a unipolar signal and output.

The switching circuit 34 selectively outputs the outputs of the three conversion circuits 31, 32, and 33, and is controlled by 2-bit setting information. For example, with setting information of "00", the switching circuit 34 is set to selectively output the output of the conversion circuit 31 and decode the AMI code into the NRZ code.

Also, the switching circuit 34 is switched to the conversion circuit 3 by the setting information of "01".
The B8ZS code bipolar signal is separated into a positive pulse PP and a negative pulse MP, which are converted into a series unipolar signal by a conversion circuit 31, and further converted into a special pattern by a conversion circuit 32. Since the unipolar signal is converted into an 8-bit "0" continuous signal and output, the B8ZS code is set to be decoded into the NRZ code.

In addition, the switching circuit 34 is switched to the conversion circuit 3 by the setting signal of "10".
3 output is selectively output, and the B6ZS code is N
It will be set to be decoded into an RZ code.

Therefore, in the backup transmitter, according to the switching signal,
It is sufficient to adopt a configuration in which the setting information of each working transmitter is selected by a selector and added to the switching circuit 34, and the decoding process can be performed in the same code format as that of the faulty working transmitter.

Note that the same applies to the encoder, and it is also possible to provide a decoding or encoding means compatible with a large number of code formats, and set the encoder using setting information. Also, it is easy to integrate the decoding layer structure including the encoder, and if the decoder and encoder are made into the same integrated circuit,
Using the same setting information, decoding and encoding can be set corresponding to a desired code format, and can be applied to transmitting and receiving apparatuses.

〔Effect of the invention〕

As explained above, the present invention uses the decoder 4 or the encoder 5, which can set decoding or encoding using setting information corresponding to the code format, to the current device 1a, lb, 2a, 2b.
A selector 6 is provided in the backup devices 3a and 3b, and a switching circuit ? When the active device is switched and connected to the standby devices 3a and 3b using a and 7b, the setting information of the active device is added to the decoder 4 or encoder 5 of the standby device via the selector 6, so that processing can be performed in the active device. The signal in the encoded format that was previously used is sent to the backup device 3a.

3b can be processed continuously, and even for working devices with different code formats, switching between working and standby devices can be performed using one standby device, making it possible to configure an economical system. There are advantages that can be achieved.

[Brief explanation of drawings]

Fig. 1 is a block diagram of the principle of the present invention, Fig. 2 is a block diagram of one embodiment of the invention, Fig. 3 is a block diagram of another embodiment of the invention, and Fig. 4 is a schematic diagram of an example of a decoder. FIG. 1a, 1b, 2a, 2b are active devices, 3a, 3b are backup devices, 4 is a decoder, 5 is an encoder, 6 is a selector, 7a,
7b is a switching circuit, 8 is a hybrid' circuit, 11, 12
．． 21 to 23 are active transmitting devices, 13.24 is a backup transmitting device, 14.25 is a decoder, 15 is a signal processing unit, 16 is a transmitting unit, 17 is a switching circuit, 1i3.19 is a hybrid circuit, 20°26 is a The selector 27 is a switching circuit. Principle block 2 of the present invention Figure 1 Figure 2 Block diagram of another example of the present invention A block diagram of the main part of an example of a setting information decoder! l A TV

Claims (1)

[Claims] A decoder (4) that performs decoding or encoding in a code format set by setting information in the active devices (1a, 1b), (2a, 2b) and the standby devices (3a, 3b), respectively. Alternatively, an encoder (5) is provided, and the preliminary device (3a, 3b) is provided with a selector (6) for selecting different setting information and applying it to the decoder (4) or encoder (5), and a switching circuit ( 7a, 7b), when the active device is switched and connected to the backup device (3a, 3b), the setting information of the active device is transferred to the backup device (3a, 3b) via the selector (6).
, 3b), in addition to the decoder (4) or encoder (5) of the active device, processing of the signal in the encoded format that was being processed by the active device is performed in the backup device (3a, 3b). Preliminary switching method.