WO2011069386A1

WO2011069386A1 - Optical network unit and method for detecting and controlling fault thereof

Info

Publication number: WO2011069386A1
Application number: PCT/CN2010/077420
Authority: WO
Inventors: 刘洋
Original assignee: 中兴通讯股份有限公司
Priority date: 2009-12-09
Filing date: 2010-09-28
Publication date: 2011-06-16
Also published as: CN101710847A

Abstract

The present invention relates to passive optics network (PON), specifically discloses an optical network unit and method for detecting and controlling fault thereof, and improves the fault detection ability of the optical network unit. The method for detecting fault in the optical network unit includes: reading the transmission optical power of an optical module for two times when a signal detection (SD) signal is outputted from the optical module, wherein the interval between the two reading operations is a set time length; judging that a fault occurs in the optical network unit when a transmission optical power value is read at both times, wherein, the value range of the set time length is greater than the time length of a lighting time slot of the optical network unit and less than the interval between two continuous natural lightings of the optical network unit. Furthermore, the present invention can also control the optical network unit by cutting off the transmission power of the optical module. Therefore, the present invention can improve the fault detecting ability of the optical network unit, and avoid impact to other normal optical network units (ONUs) from the faulty ONU by cutting off the transmission power of the optical module.

Description

Optical network unit and fault detection and control method thereof

The present invention relates to a passive optical network, and more particularly to an optical network unit and a method for detecting and controlling the same. Background technique

With the continuous enrichment of multimedia services, the demand for access network bandwidth is increasing. It is in this case that passive optical networks (PON, Passive Optics Network) are widely used, which can provide long Distance, large bandwidth access, which is not possible with traditional asymmetric digital subscriber line (ADSL).

PON refers to passive electronic equipment consisting of an optical line terminal (OLT, Optics Line Terminate) as a central office equipment, an optical network unit (ONU, Optic Network Unit) as an end device, and an optical distribution network (ODN, Optics Distribution Network). Equipment system. Passive is one of them. The basic structure of the ONU is shown in Figure 1. It mainly includes the main central processing unit (CPU), optical module and transmission power module. The main CPU is configured to control the optical module to send data in a specific time slot, and the sending power module is configured to receive control of the main CPU and send power to the optical module.

In the PON network, the downlink central office equipment continuously broadcasts and transmits, and the ONU selectively receives; the uplink sub-slot burst sends, and each ONU transmits data only in the time slot allocated by the central office. However, in practical applications, it may happen that one or several ONUs are faulty and are not controlled by the central office equipment, such as the case of long-lighting, which will inevitably affect the data transmission of other ONUs, affecting normal conditions. Business. Summary of the invention

The invention provides an optical network unit and a fault detection and control method thereof, which can improve the detection capability of the ONU, and prevent the faulty ONU from affecting other normal working ONUs.

In view of the above, the present invention provides a fault detection method for an optical network unit, including: when the optical module has a signal detection (SD, Signal Detection) signal output, the optical power of the optical module is read twice, twice. When the optical power of the optical network is read, it is determined that the optical network unit is faulty; wherein, the time interval between the two reading operations is a set duration, and the first value range of the set duration is greater than the light. The duration of one illuminating time slot of the network unit is less than the time interval during which the optical network unit illuminates normally twice.

Further, the method further includes:

Detecting the pulse width of the illumination control signal when only the transmission optical power is read once or the transmission optical power is not read twice; when the pulse width of the illumination control signal is not within the second value range, determining the light The network unit is faulty, and the second value range is greater than 0 and less than the duration of one illuminating time slot of the optical network unit. The illuminating control signal is a signal that the optical network unit controls the illuminating of the optical module.

In the above method, the method further includes:

Determining whether the illumination control signal is the same as the illumination indication signal sent by the optical module when the pulse width of the illumination control signal is within the second value range, and determining if the illumination control signal and the illumination indication signal are not the same The optical network unit fails; if the lighting control signal is the same as the lighting indication signal, the failure detection is resumed.

The method further includes: determining that the sending power of the optical module is turned on before the outputting the optical power of the optical module is performed twice when the optical module has an SD signal output.

In the above method, before the determining that the sending power of the optical module is turned on, the method further includes: determining whether the optical network unit starts the long light detecting function, and if the long light detecting function is activated, determining whether the sending power of the optical module is On; if long illuminating detection is not activated The above method further includes:

When it is determined that the optical network unit is faulty, the transmission power of the optical module is cut off.

In order to achieve the above method, the present invention provides an optical network unit, including a main CPU and an optical module, where the main CPU is configured to: when determining that the optical module has a signal detection SD signal output, read the optical module twice. Transmitting optical power, when the transmitted optical power can be read twice, determining that the optical network unit is faulty;

The time interval between the two read operations is a set duration, and the first value range of the set duration is greater than the duration of one of the optical network slots of the optical network unit and is smaller than the continuous duration of the optical network unit. The time interval between two normal illuminations.

Further, the main CPU includes:

The transmitting optical power reading module is specifically configured to read the transmitting optical power of the optical module in two times when determining that the optical module has an SD signal output;

The fault determining module is specifically configured to determine that the optical network unit is faulty when the transmitted optical power can be read twice.

Further, the main CPU further includes:

a pulse width detecting module, configured to detect a pulse width of the light emission control signal when only one transmission optical power is read once or no transmission optical power is read twice;

The fault determining module is further configured to: determine whether the pulse width is within a second value range, and determine that the optical network unit is faulty when the pulse width of the light emission control signal is not within the second value range, The second value range is greater than 0 and less than the duration of one illuminating time slot of the optical network unit.

Further, the fault determining module is further configured to: determine, when the pulse width of the lighting control signal is within the second value range, whether the lighting control signal is the same as the lighting indication signal sent by the optical module, and determine the location when the two are different The optical network unit has failed. In the above optical network unit, the main CPU includes:

The transmitting optical power reading module is specifically configured to read the transmitting optical power of the optical module twice when the optical module has an SD signal output;

The control module is configured to cut off the sending power of the optical module when the optical network unit fails.

Further, the main CPU further includes:

a pulse width detecting module, configured to detect a pulse width of the illumination control signal when only one transmission optical power is read once or no transmission optical power is read twice;

The control module is further configured to: when the pulse width of the illumination control signal is not within the second value range, cutting off the transmission power of the optical module, where the second value range is greater than 0 and less than one illumination time slot of the optical network unit duration.

The control module is further configured to: when the pulse width of the illumination control signal is within the second value range, determine whether the illumination control signal is the same as the illumination indication signal sent by the optical module, and cut the optical module when the two are different. Send power.

The present invention provides a fault detection and control method for an ONU. In an optical network unit using the method of the present invention, the duration of the main CPU in more than one illuminating time slot is less than the time during which the optical network unit normally emits light twice. During the interval, when the optical power of the optical module can be read twice, the optical module is determined to be abnormal, and then the optical network unit is determined to be faulty.

Further, when only the transmission optical power is read once or the transmission optical power is not read twice, the main CPU can also determine whether the optical module is abnormal by detecting the pulse width of the illumination control signal, thereby determining the optical network unit. Whether the fault occurs, and the transmission power of the optical module is cut off when the optical network unit fails, so as not to affect other normal working ONUs;

Further, the main CPU can also determine whether the optical network unit is faulty by determining whether the lighting control signal is the same as the lighting indication signal sent by the optical module, and further whether to cut off the transmission power of the optical module. It can be seen that the optical network unit can be improved by the method of the invention. The obstacle detection capability enables effective control of the optical network unit at the same time, so as to prevent the faulty ONU from affecting other normally working ONUs. DRAWINGS

Figure 1 is a schematic diagram of the basic structure of the ONU;

2 is a schematic flowchart of a method for controlling an ONU according to an embodiment of the present invention; FIG. 3 is a schematic diagram of a time slot for normal ONU of an ONU;

4 is a schematic diagram of a pulse width detection principle of an illumination control signal;

5 is a schematic diagram showing the principle of detecting whether the illumination control signal and the illumination indication signal are the same; FIG. 6 is a schematic diagram of a first optical network unit according to an embodiment of the present invention;

FIG. 7 is a schematic diagram of a second optical network unit according to an embodiment of the present invention. detailed description

In order to ensure the normal operation of the network, when one or some ONUs are in a long-light state due to the failure of the burst function, the faulty ONU needs to be controlled so as not to affect other normal working ONUs.

As shown in FIG. 3, a schematic diagram of a time slot in which an optical network unit is normally illuminated, and a time period in which an optical network unit is normally illuminated when the optical network unit is normally illuminated is t1, and the optical network unit is illuminated during normal operation. The time slot will illuminate, and the duration of the illuminating time slot will not be illuminated. After the elapse of time 12, the central office will allocate the illuminating time slot again for the optical network unit, and the optical network unit starts to emit light again; that is, if When the optical network unit works normally, the optical network unit emits light in the (0, tl) time range, does not emit light in the (tl, 12) time range, continues to emit light in the (t2, 13) time range, and so on.

Therefore, the interval time t is set by the interval setting, and when the optical module has the SD signal output, the optical power of the optical network unit is detected twice, and it can be determined whether the optical network unit is faulty, as shown in FIG. 3, the setting duration is set. t must be greater than t1 and less than t2-tl, that is, set the duration The duration of the range is greater than the duration of one illuminating time slot and is less than the time interval of the normal illuminating of the optical network unit twice, so that not only the optical power of the optical module can be read twice in one illuminating time slot, but also It is ensured that the transmitted optical power of the optical module is not read in two consecutive normal time slots. Therefore, if the transmitted optical power of the optical module is read twice in the range of the set duration, the light is indicated. The module is in a long-light state, that is, the optical network unit is faulty. For the faulty optical network unit, the transmission power of the optical module can be cut off to avoid affecting other optical network units that are working normally.

Based on the above principles, the embodiment of the present invention provides a method for controlling an ONU, where the main CPU of the optical network unit is in a time interval greater than one illuminating time slot and less than a time interval in which the optical network unit continuously emits light twice, if The optical power of the optical module can be read twice, and the abnormality of the optical module is determined, and the sending power of the optical module is cut off;

Further, when only the transmission optical power is read once or the transmission optical power is not read twice, the main CPU can also determine whether the optical module is abnormal by detecting the pulse width of the illumination control signal, and when the optical module is abnormal. Cutting off the transmission power of the optical module; wherein, the illumination control signal is a signal that the optical network unit controls the illumination of the optical module, that is, a signal sent by the main CPU for controlling the illumination of the optical module;

Further, the main CPU can also control whether to cut off the transmission power of the optical module by determining whether the illumination control signal is the same as the illumination indication signal sent by the optical module. By using the above method of cutting off the power, the ONU that is faulty can be prevented from affecting other ONUs that are working normally, and the normal service is guaranteed. The illumination indication signal is a signal output by the optical module indicating that it is emitting light.

As shown in FIG. 2, a method for controlling an ONU according to an embodiment of the present invention includes:

Step 201: The main CPU determines whether the ONU starts the long-light detection function. If it is started, it performs step 202, otherwise it continues to determine whether the long-light detection function is activated. If it is not activated, it is periodically determined whether the optical network unit starts the long illuminating detection function. The specific fault detection period can be set according to the actual situation.

Step 202: The main CPU determines whether the sending power of the optical module is turned on. If yes, step 203 is performed. If not, step 201 is performed;

Step 203: The main CPU determines whether the optical module has an SD (Signal Detection) signal output. If there is an SD signal output, step 204 is performed. If no SD signal is output, the process returns directly to step 201;

If the optical module does not have an SD signal output, it indicates that the optical module is not inserted into the optical fiber or the optical fiber is damaged. At this time, the other ONUs are not affected, so there is no need for processing, and the process returns directly to step 201;

Step 204: The main CPU reads the transmit optical power of the optical module twice. The time interval between the two read operations is the set duration. If the transmit optical power can be read twice, the optical module is long. The illuminating state, that is, the ONU is faulty, step 208 is performed; if the transmitting optical power is read only once, or the transmitting optical power is not read twice, step 205 is performed;

The first value range of the set duration is greater than the duration of one of the optical network units of the optical network unit, and is less than the time interval during which the optical network unit normally emits light twice.

Step 205: The main CPU detects a pulse width of the illumination control signal.

The principle of the pulse width detection of the illumination control signal can be referred to FIG. 4. This step mainly acquires the pulse width of the illumination control signal through a multi-bit counter. When the illumination control pulse signal of the illumination control signal starts, the multi-bit counter Clearing and starting counting, the multi-bit counter counting ends at the end of the pulse, and then the pulse width of the illumination control signal is obtained by multiplying the count value by the counting clock period;

Step 206: Determine whether the pulse width of the illumination control signal is within a second value range. If the pulse width is within the second value range, perform step 207, if the pulse width is not within the second value range. , step 208 is performed; Wherein, when the pulse width of the illumination control signal is not within the second value range, indicating that

The ONU is faulty. Therefore, you need to cut off the transmit power of the optical module.

Generally, the second value range is greater than 0 and less than the length of time that the central office device allocates to one of the optical network slots of the optical network unit. Therefore, when the pulse width of the illumination control signal is not within the second value range, that is, when the pulse width is greater than t1 or 0, this indicates that the control signal is not controlled by the central office device, and thus the ONU is faulty. ;

Step 207: The main CPU determines whether the illumination control signal is the same as the illumination indication signal sent by the optical module. If the two are the same, it indicates that the ONU is normal at this time, and returns to step 201 to restart the periodic fault detection; if the illumination indication signal is If the ONU is abnormal, that is, the ONU is faulty, go to step 208;

For example, referring to FIG. 5, in order to detect whether the illumination control signal and the illumination indication signal are the same, the embodiment may detect whether the illumination control signal and the illumination indication signal are the same through an AND gate circuit, that is, the main CPU sends out The illumination control signal and the illumination indication signal sent by the optical module are input to the same OR gate circuit. If the output is high level, the two are the same; if the low level is output, the two are different;

It should be noted that if the illumination control signal is opposite to the illumination indication signal sent by the optical module, the reverse adjustment may be first performed to make the two are the same, and then whether the two are the same.

Step 208: The main CPU cuts off the transmission power of the optical module, and returns to step 201.

By using the methods of the present invention, it is possible to directly detect whether an abnormality occurs in the optical module, and when an abnormality occurs, the transmission power of the optical module is cut off by the control of the main CPU, thereby avoiding the failure of the ONU optical network unit to other The impact of the normal ONU optical network unit ensures the normal operation of the service.

The embodiment of the present invention further provides a fault detection method for the optical network unit. In the foregoing steps, the step 208 is not necessary, and in step 204, step 206, and step 207, when the optical network unit is detected to be faulty, Can end directly, or return to step 201 to continue Periodic fault detection. In this way, the optical network unit can automatically detect the fault. As shown in FIG. 6, the optical network unit includes the main CPU and the optical module, and the main CPU is provided in the embodiment of the present invention. The method is: when determining that the optical module has the signal detection SD signal output, reading the transmission optical power of the optical module twice, and when the transmission optical power can be read twice, determining that the optical network unit is faulty;

In the above optical network unit, the main CPU includes: a transmit optical power reading module 61, configured to read the transmit optical power of the optical module twice in two steps when determining that the optical module has an SD signal output, wherein the read optical power is read twice. The time interval between them is the set time;

The fault determining module 62 is configured to determine that the optical network unit is faulty when the transmit optical power can be read twice, and the first value range of the set duration is greater than the duration of one illuminating time slot of the optical network unit. And less than the time interval in which the optical network unit continuously emits light twice.

In the above optical network unit, the main CPU further includes:

The pulse width detecting module 63 is configured to detect a pulse width of the light emission control signal when only one transmission optical power is read or not, and the light emission control signal is controlled by the optical network unit. The signal that the light module emits light.

The fault determining module 62 is further configured to: determine whether the pulse width is within a second value range, and determine that the optical network unit is faulty when the pulse width of the light emission control signal is not within the second value range, and the second value The range is greater than 0 and less than the length of one of the light-emitting time slots of the optical network unit.

The fault determining module 62 is further configured to: determine, when the pulse width of the light emission control signal is within the second value range, whether the light emitting control signal and the light emitting indication signal sent by the optical module are Similarly, when it is determined that the illumination control signal is different from the illumination indication signal sent by the optical module, it is determined that the optical network unit is faulty.

In addition, the embodiment of the present invention further provides an optical network unit that uses the foregoing control method. As shown in FIG. 7, the optical network unit includes: a main CPU and an optical module; and the main CPU is configured to: When the signal detection SD signal is output, the transmission optical power of the optical module is read twice, and when the transmission optical power can be read twice, it is determined that the optical network unit is faulty;

In the above optical network unit, the main CPU includes:

The transmitting optical power reading module 71 is configured to read the transmitting optical power of the optical module twice when the optical module has the SD signal output, wherein the time interval between the two readings is a set duration;

The control module 72 is configured to: when determining that the optical network unit is faulty, cut off the sending power of the optical module, where the first value range of the set duration is greater than a duration of one illuminating time slot of the optical network unit and less than the light The time interval during which the network unit is normally illuminated twice.

In the above optical network unit, the main CPU further includes:

The pulse width detecting module 73 is configured to detect a pulse width of the light emitting control signal when the optical power is read only once or not, or when the transmitting optical power is not read twice;

The control module 72 is further configured to cut off the transmission power of the optical module when the pulse width of the illumination control signal is not within the second value range, where the second value range is greater than 0 and less than the duration of one illumination slot of the optical network unit. .

The control module 72 is further configured to: determine, when the pulse width of the illumination control signal is within the second value range, whether the illumination control signal is the same as the illumination indication signal sent by the optical module, and At the same time, the transmission power of the optical module is cut off.

In the above embodiments, the descriptions of the various embodiments have different emphasis, and in some embodiments, For a detailed description, refer to the related description of other embodiments. The above is only the preferred embodiment of the present invention, and is only intended to illustrate and explain the present invention, and is not intended to limit the scope of the present invention.

Claims

Claim

A method for detecting a fault of an optical network unit, the method comprising: when the optical module of the optical network unit has a signal detection SD signal output, reading the optical power of the optical module twice, when twice When the transmitted optical power can be read, it is determined that the optical network unit is faulty;

The time interval between the two read operations is a set duration; the first value range of the set duration is greater than the duration of one of the optical network slots of the optical network unit, and is smaller than the continuous duration of the optical network unit. The time interval between two normal illuminations.

2. The method according to claim 1, wherein the method further comprises: detecting a pulse width of the illumination control signal when only one transmission optical power is read once or no transmission optical power is read twice;

When the pulse width of the illumination control signal is not within the second value range, it is determined that the optical network unit is faulty, and the second value range is greater than 0 and less than the duration of one illumination time slot of the optical network unit.

The method according to claim 2, further comprising: determining a lighting control signal and a lighting indication signal emitted by the optical module when a pulse width of the lighting control signal is within the second value range Whether the same is true, if the lighting control signal is different from the lighting indication signal, it is determined that the optical network unit is faulty; if the lighting control signal is the same as the lighting indication signal, periodic fault detection is restarted.

The method according to claim 1, 2 or 3, wherein before the optical module has an SD signal output, the optical power of the optical module is read twice, and the method further comprises: determining The transmit power of the optical module is turned on.

The method of claim 4, wherein before the determining that the transmission power of the optical module is turned on, the method further includes:

Determining whether the optical network unit initiates a long illumination detection function, if a long illumination detection has been initiated The measurement function determines whether the transmission power of the optical module is turned on; if the long illumination detection is not activated

6. The method of claim 5, further comprising:

An optical network unit, comprising a main CPU and an optical module, wherein the main CPU is configured to: when determining that the optical module has a signal detection SD signal output, read the optical power of the optical module twice; When the optical power of the optical network can be read twice, it is determined that the optical network unit is faulty; wherein, the time interval between the two reading operations is a set duration, and the first value range of the set duration The duration of one illuminating time slot of the optical network unit is greater than the time interval of the optical network unit for two consecutive normal illuminations.

The optical network unit according to claim 7, wherein the main CPU comprises: a transmitting optical power reading module, specifically configured to read the optical module twice when determining that the optical module has an SD signal output. Transmit optical power;

The optical network unit according to claim 8, wherein the main CPU further comprises:

The fault determining module is further configured to: determine whether the pulse width is within a second value range, and when the pulse width is not within the second value range, determine that the optical network unit is faulty, and the second value The range is greater than 0 and less than the length of one of the light-emitting time slots of the optical network unit.

The optical network unit according to claim 9, wherein the fault determining module is further configured to: when the pulse width of the light emission control signal is within the second value range, determine the light emission control signal Whether it is the same as the illuminating indication signal emitted by the optical module, and is different in the two It is determined that the optical network unit is faulty.

The optical network unit according to claim 7, wherein the main CPU comprises: a transmitting optical power reading module, specifically configured to read the optical module twice when the optical module has an SD signal output Transmit optical power;

The optical network unit according to claim 11, wherein the main CPU further comprises:

a pulse width detecting unit, configured to detect a pulse width of the light emission control signal when only one transmission optical power is read once or no transmission optical power is read;

The control unit is further configured to: when the pulse width of the illumination control signal is not within the second value range, cutting off the transmission power of the optical module, where the second value range is greater than 0 and less than one illumination time slot of the optical network unit duration.

The optical network unit according to claim 12, wherein the control module is further configured to: when the pulse width of the illumination control signal is within the second value range, determine the illumination control signal and Whether the illumination indication signals sent by the optical module are the same, and the transmission power of the optical module is cut off when the two are different.