WO2016192285A1

WO2016192285A1 - System and method for detecting abnormal light emission of ont by olt in pon system

Info

Publication number: WO2016192285A1
Application number: PCT/CN2015/093003
Authority: WO
Inventors: 吴夕周; 杨传培
Original assignee: 上海斐讯数据通信技术有限公司
Priority date: 2015-06-02
Filing date: 2015-10-28
Publication date: 2016-12-08
Also published as: CN104852764A

Abstract

Provided are a system and method for detecting abnormal light emission of an optical network terminal (ONT) by an optical line terminal (OLT) in a passive optical network (PON) system, comprising: a CPU module, a PON time slot control module, an OLT optical transceiver module, and an optical signal timing module. The OLT optical transceiver module is connected to the PON time slot control module. The PON time slot control module is connected to the optical signal timing module and the CPU module. The optical signal timing module is connected to the CPU module. The system and method for detecting abnormal light emission of the ONT by the OLT in the PON system provided in the present invention is capable of precisely detecting an uplink data state of each ONT, detecting performance degradation of a single ONT, and quickly positioning a degradation failure point so as to eliminate potential risks before further degradation can occur.

Description

System and method for detecting abnormal light emission of ONT in PON system

Technical field

The present invention relates to the technical field of optical network communication, and particularly relates to an optical network terminal (OLT) detecting an optical network terminal (ONT) abnormality in a passive optical network (PON) system. System and method of illumination.

Background technique

At present, the PON optical network has been widely used in the access network. The network topology is that one OLT port is connected to multiple ONT devices, and the downlink data is broadcasted by the OLT to all ONTs. Multiple ONT devices transmit uplink data on the same wavelength by time division multiplexing, and the allocation of uplink time slots is determined by the OLT. Therefore, the network topology of the PON is a point-to-multipoint master-slave communication mechanism, and the OLT precisely controls the transmission start time and end time of each ONT device uplink data. Such a network topology has the characteristics of simple networking, flexible configuration, and strong scalability, and has become the mainstream technology of the access network.

Since the uplink data uses the time division multiplexing mechanism, all ONT uplink data are transmitted on the same wavelength of the same fiber, so it is very important to strictly comply with this mechanism for each ONT uplink data slot. If the ONT is abnormally illuminated due to the design or fault of the software or hardware, the uplink data slot does not meet the requirements, which may pollute the entire optical link. This may cause other normal ONT uplink data to be erroneous or even completely impossible. jobs. Therefore, it is very important to periodically check the fault point of the ONT.

ONT uplink data Due to the use of a burst mechanism, abnormal illumination failures can be caused by many reasons. The most common are software bugs, abnormal illumination caused by hardware failures, and reduced switching performance caused by aging of optical devices. Since there is no standard for PON optical link performance detection and fault protection mechanisms, there is no uniform approach to detection and protection mechanisms in the equipment.

In the prior art, the detection protection is performed on the ONT side by using the scheme shown in FIG. The working principle of the solution is that the ONT optical module first receives and parses the downlink optical data packet sent by the OLT, converts it into an electrical signal, and then sends it to the ONT PON protocol module for protocol analysis processing, and then the ONT PON protocol module according to the parsed OLT instruction. Sending uplink electrical data to the ONT optical module in a specified time slot, and simultaneously outputting an ONT optical module uplink transmission enable signal TX_EN. The ONT optical module outputs an effective optical signal to transmit uplink optical data on the optical link during the period when the TX_EN is valid. At the same time, an ONT optical module uplink sending status signal TX_SD is sent to the detecting module, and the detecting module detects the effective duration of the status signal TX_SD of the ONT optical module. In the case where the status signal of the ONT optical module TX_SD indicates normal, the scheme can be detected for the abnormal illumination of the ONT optical module due to software or local hardware failure. However, the time slot occupied by the aging of the illuminating device of the ONT optical module and the decrease of the switching speed have no detection capability, and at the same time, it cannot detect the state of the uplink optical link of the trunk.

The solution shown in Figure 2 is to perform detection protection on the OLT side. The detecting module in the solution detects the state of the optical link by detecting the length of the uplink receiving state signal RX_SD of the OLT optical module. Although the scheme can detect the link fault caused by the abnormal illuminating of the ONT, because the EPON ONT uplink time slot length allocation is not fixed, there is no way to detect the time slot occupation problem caused by the aging of the ONT optical device, and it is impossible to accurately detect each ONT. Uplink optical link status.

Summary of the invention

In view of the above disadvantages of the prior art, an object of the present invention is to provide a system and method for detecting abnormal ONT of an ONT in an OLT system, which can accurately detect the transmission start time and sum of uplink data of each ONU on the OLT side. At the end time, the uplink optical link status of each ONT is accurately detected by comparing with the time slot allocated by the OLT.

To achieve the above and other related purposes, the present invention provides a system for detecting an abnormal illumination of an ONT by an OLT in a PON system, including a CPU module, a PON time slot control module, an OLT receiving and emitting module, and an optical signal timing module; Connected to the PON time slot control module, the PON time slot control module is connected to the optical signal timing module and the CPU module, and the optical signal timing module is further connected to the CPU module; The module is configured to receive an uplink optical signal, and send an uplink receiving status signal to the optical signal timing module when detecting a valid uplink optical signal; the PON time slot control module is configured to allocate an uplink time slot for each ONT, and The time slot allocation information is transmitted to the CPU module; and when receiving the detection instruction sent by the CPU, sending a trigger signal to the optical signal timing module; the optical signal timing module is configured to receive the trigger After the signal, the start time and the end time of receiving the uplink receiving status signal are recorded and transmitted to the CPU module; the CPU module is configured to send a detection instruction And the PON time slot control module; and comparing the time slot allocation information sent by the PON time slot control module with the start time and end time of the uplink receiving status signal sent by the optical signal timing module, and determining the ONT uplink light Whether the link meets the time slot requirement.

According to the above PON system, the OLT detects an abnormal illumination of the ONT, wherein: the PON slot control module allocates an uplink slot for each ONT according to the PON protocol.

According to the above PON system, the OLT detects an abnormal illumination of the ONT, wherein: the optical signal timing module performs a timing function when the trigger signal is valid.

According to the above PON system, the OLT detects an abnormal illumination of the ONT, wherein: the alarm module further includes an alarm module, and the alarm module is connected to the CPU module, and is configured to issue an alarm when the ONT uplink optical link does not meet the time slot requirement.

According to the above PON system, the OLT detects an abnormal illumination of the ONT, wherein: the CPU module works to determine whether the ONT uplink optical link meets the time slot requirement according to the following rules:

When the start time and the end time of the uplink receiving status signal are in the uplink time slot allocated by the ONT, the OLT uplink optical link satisfies the time slot requirement;

When the start time and the end time of the uplink receiving status signal are not completely in the uplink time slot allocated by the ONT, the OLT uplink optical link does not satisfy the time slot requirement.

Meanwhile, the present invention also provides a method for detecting abnormal illumination of an ONT by an OLT in a PON system, including the following steps:

Step S1: The CPU module sends a detection instruction to the PON slot control module.

Step S2: The PON slot control module allocates an uplink time slot for the ONT, and transmits the time slot allocation information to the CPU module; and when receiving the detection command sent by the CPU, sends a trigger signal to the optical signal timing module;

Step S3: The OLT receiving and receiving module receives the uplink optical signal, and sends an uplink receiving status signal to the optical signal timing module when the valid uplink optical signal is detected;

Step S4, the optical signal timing module records the start time and the end time of receiving the uplink receiving state signal, and transmits the same to the CPU module;

Step S5: The CPU module compares the time slot allocation information sent by the PON time slot control module with the start time and the end time of the uplink receiving state signal sent by the optical signal timing module, and determines whether the ONT uplink optical link meets the time slot requirement.

According to the above method for detecting an abnormal illumination of an ONT in an OLT system, in the step S2, the PON slot control module allocates an uplink slot for each ONT according to the PON protocol.

According to the above method, the OLT detects an abnormal illumination of the ONT in the PON system, wherein: in the step S4, the optical signal timing module performs a timing function when the trigger signal is valid.

According to the above method, the OLT detects the abnormal illuminating of the ONT in the PON system, wherein: in the step S5, the CPU module works to determine whether the ONT uplink optical link meets the time slot requirement according to the following rules:

According to the foregoing method for detecting an abnormal illumination of an ONT in an OLT system, the method further includes the step S6, when the ONT uplink optical link does not meet the time slot requirement, an alarm is sent through the alarm module.

As described above, in the PON system of the present invention, the OLT detects a system and method for abnormally emitting light of an ONT, and has the following beneficial effects:

(1) It can accurately detect the status of each ONT uplink data;

(2) being able to detect performance degradation of a single ONT;

(3) It is possible to quickly locate the degraded fault point so as to eliminate the hidden danger ahead of further deterioration.

DRAWINGS

1 is a schematic structural diagram of an ONT transmission optical signal detecting system in the prior art;

2 is a schematic structural diagram of an OLT receiving optical signal detecting system in the prior art;

3 is a schematic structural diagram of a preferred embodiment of a system for detecting abnormal illumination of an ONT by an OLT in a PON system according to the present invention;

4 is a schematic structural view showing another preferred embodiment of a system for detecting abnormal light emission of an ONT by an OLT in the PON system of the present invention;

5 is a timing chart showing an ONT uplink data slot detection parameter in the present invention;

6 is a flow chart showing a preferred embodiment of a method for an OLT to detect an abnormal illumination of an ONT in a PON system of the present invention;

7 is a flow chart showing another preferred embodiment of a method for an OLT to detect an abnormal illumination of an ONT in a PON system of the present invention.

Component label description

1 CPU module

2 PON time slot control module

3 OLT receiving light module

4 optical signal timing module

5 alarm module

detailed description

The embodiments of the present invention are described below by way of specific examples, and those skilled in the art can readily understand other advantages and effects of the present invention from the disclosure of the present disclosure. The present invention may be embodied or applied in various other specific embodiments, and various modifications and changes can be made without departing from the spirit and scope of the invention.

It should be noted that the illustrations provided in the present embodiment merely illustrate the basic concept of the present invention in a schematic manner, and only the components related to the present invention are shown in the drawings, instead of the number and shape of components in actual implementation. Dimensional drawing, the actual type of implementation of each component's type, number and proportion can be a random change, and its component layout can be more complicated.

The system and method for detecting abnormal ONT of the ONT in the PON system of the present invention utilizes the protocol mechanism of the PON to accurately detect the transmission start time and end time of the uplink data of each ONT uplink illumination link on the OLT side, and Minute The time slots assigned to the ONT are compared to determine if they meet the time slot requirements and an alarm is issued when the time slot requirements are not met.

Referring to FIG. 3, the system for detecting abnormal ONT of the ONT in the PON system of the present invention includes a CPU module 1, a PON slot control module 2, an OLT receiving and emitting module 3, and an optical signal timing module 4. The OLT receiving and transmitting module 3 is connected to the PON time slot control module 2, the PON time slot control module 2 is connected to the optical signal timing module 4 and the CPU module 1, and the optical signal timing module 4 is connected to the CPU module 1.

The OLT receiving and receiving module 3 is configured to receive the uplink optical signal, and send the uplink receiving state signal RX_SD to the optical signal timing module 4 when the valid uplink optical signal is detected.

The PON slot control module 2 is configured to allocate an uplink time slot for each ONT and transmit the time slot allocation information to the CPU module 1; and when receiving the detection instruction sent by the CPU, send the trigger signal TRIG to the optical signal timing module. 4.

The PON slot control module 2 allocates an uplink slot for each ONT according to the PON protocol.

The optical signal timing module 4 is configured to record the start time and the end time of receiving the uplink reception status signal RX_SD after receiving the trigger signal TRIG, and transmit the same to the CPU module 1.

The optical signal timing module 4 performs the timing function only when the trigger signal is active. When the optical signal timing module 4 receives the trigger signal TRIG, the timing function is activated; if the optical signal timing module 4 does not receive the trigger signal TRIG, the timing function is stopped.

Specifically, the optical signal timing module 4 records the start time and the end time of receiving the uplink reception state signal RX_SD through a timer.

The CPU module function 1 is used to send a detection command to the PON time slot control module 2; and compare the time slot allocation information sent by the PON time slot control module 2 with the start time of the uplink reception status signal RX_SD sent by the optical signal timing module 4 At the end time, it is determined whether the ONT uplink optical link satisfies the time slot requirement.

Preferably, the alarm module 5 is further included as shown in FIG. The alarm module 5 is connected to the CPU module 1 for issuing an alarm when the ONT uplink optical link does not meet the time slot requirement, so as to eliminate hidden dangers in time. Specifically, the alarm module may employ a buzzer, a voice alarm, or the like.

FIG. 5 is a timing diagram showing several real-time signals and time points in a system in which an OLT detects an abnormal illumination of an ONT in a PON system of the present invention. Among them, TRIG is the trigger signal output by the PON time slot control module, which is used to trigger the start of the optical signal timing module; T0, T1 is the trigger effective time sent by the PON time slot control module; T2, T3 is the PON time slot control module allocation The time window for the ONT; RX_SD is the uplink receiving status signal sent by the OLT receiving and receiving module; T4 and T5 are the starting time and ending time obtained by the optical signal timing module for monitoring the RX_SD signal.

If T4 and T5 are in the time slot of T2-T3, it indicates that the OLT uplink optical link satisfies the time slot requirement; if the time slot of T4-T5 is not completely in the time slot of T2-T3, it indicates that the OLT The upstream optical link does not meet the slot requirements.

Specifically, when determining whether the ONT uplink optical link meets the time slot requirement, the following two algorithms may be used:

1) If [T4, T5] ∈ [T2-T3], it indicates that the OLT uplink optical link meets the time slot requirement;

If

It indicates that the OLT uplink optical link does not meet the time slot requirement.

2) If T5 ≤ (T3-T0) or T4 ≥ (T2-T0), it indicates that the OLT uplink optical link meets the time slot requirement;

If T5≥(T3-T0) or T4≤(T2-T0), it indicates that the OLT uplink optical link does not meet the slot requirement.

Referring to FIG. 6, a method for detecting an abnormal illumination of an ONT by an OLT in a PON system of the present invention includes the following steps:

Step S1: The CPU module sends a detection instruction to the PON time slot control module.

Step S2: The PON slot control module allocates an uplink time slot to the ONT, and transmits the time slot allocation information to the CPU module. When receiving the detection command sent by the CPU, the PON time slot control module sends a trigger signal to the optical signal timing module.

It is assumed that the trigger signal is valid for the T0-T1 period. The optical signal timing module performs the timing operation if and only if the trigger signal is active. The uplink time slot allocated by the PON slot control module for the ONT is T2-T3.

Step S3: The OLT receiving and receiving module receives the uplink optical signal, and sends an uplink receiving state signal RX_SD to the optical signal timing module when the valid uplink optical signal is detected.

Step S4: The optical signal timing module records the start time and the end time of receiving the uplink receiving state signal RX_SD, and transmits the same to the CPU module.

Specifically, during the period when the trigger signal TRIG received by the optical signal timing module is valid, the optical signal timing module records the start time and the end time of receiving the uplink receiving state signal RX_SD through the timer. It is assumed that the start time and end time of the uplink reception status signal RX_SD are T4 and T5, respectively.

Step S5: The CPU module compares the time slot allocation information sent by the PON time slot control module with the start time and the end time of the uplink receiving state signal RX_SD sent by the optical signal timing module, and determines whether the ONT uplink optical link meets the time slot requirement.

If

Preferably, as shown in FIG. 7, step S6 is further included, and when the ONT uplink optical link does not meet the time slot requirement, an alarm is sent through the alarm module. Specifically, the alarm module may employ a buzzer, a voice alarm, or the like.

In summary, the system and method for detecting abnormal ONT of the ONT in the PON system of the present invention can accurately detect the uplink data state of each ONT; can detect the performance degradation of a single ONT; and can quickly locate the degraded fault point, It is convenient to eliminate hidden dangers before further deterioration. Therefore, the present invention effectively overcomes various shortcomings in the prior art and has high industrial utilization value.

The above-described embodiments are merely illustrative of the principles of the invention and its effects, and are not intended to limit the invention. Modifications or variations of the above-described embodiments may be made by those skilled in the art without departing from the spirit and scope of the invention. Therefore, all equivalent modifications or changes made by those skilled in the art without departing from the spirit and scope of the invention will be covered by the appended claims.

Claims

A system for detecting an abnormal illumination of an ONT by an OLT in a PON system, comprising: a CPU module, a PON slot control module, an OLT receiving and emitting module, and an optical signal timing module; the OLT receiving and receiving module and the PON slot control module Connected, the PON time slot control module is connected to the optical signal timing module and the CPU module, and the optical signal timing module is further connected to the CPU module;

The OLT receiving and receiving module is configured to receive an uplink optical signal, and send an uplink receiving status signal to the optical signal timing module when detecting a valid uplink optical signal;

The PON slot control module is configured to allocate an uplink time slot for each ONT, and transmit the time slot allocation information to the CPU module; and send a trigger signal to the location when receiving the detection instruction sent by the CPU Optical signal timing module;

The optical signal timing module is configured to record, after receiving the trigger signal, a start time and an end time of receiving an uplink receiving state signal, and transmit the same to the CPU module;

The CPU module is configured to send a detection instruction to the PON slot control module; and compare time slot allocation information sent by the PON slot control module with an uplink reception status signal sent by the optical signal timing module. The start time and the end time determine whether the ONT uplink optical link satisfies the time slot requirement.
The system for detecting abnormal ONT of an ONT in the PON system according to claim 1, wherein the PON slot control module allocates an uplink slot for each ONT according to the PON protocol.
The system for detecting an abnormal illumination of an ONT by an OLT in the PON system according to claim 1, wherein the optical signal timing module performs a timing function when the trigger signal is valid.
The OLT system of claim 1, wherein the OLT detects an abnormal illumination of the ONT, and further includes an alarm module, wherein the alarm module is connected to the CPU module, and the uplink optical link does not satisfy the time slot in the ONT. Alert when requested.
The system for detecting abnormal ONT of an ONT in the PON system according to claim 1, wherein the CPU module determines whether the ONT uplink optical link satisfies the time slot requirement according to the following rules:

When the start time and the end time of the uplink receiving status signal are in the uplink time slot allocated by the ONT, the OLT uplink optical link satisfies the time slot requirement;

When the start time and the end time of the uplink receiving status signal are not completely in the uplink time slot allocated by the ONT, Then, the OLT uplink optical link does not meet the time slot requirement.
A method for detecting abnormal light emission of an ONT by an OLT in a PON system, comprising: the following steps:

Step S1: The CPU module sends a detection instruction to the PON slot control module.

Step S2: The PON slot control module allocates an uplink time slot for the ONT, and transmits the time slot allocation information to the CPU module; and when receiving the detection command sent by the CPU, sends a trigger signal to the optical signal timing module;

Step S3: The OLT receiving and receiving module receives the uplink optical signal, and sends an uplink receiving status signal to the optical signal timing module when the valid uplink optical signal is detected;

Step S4, the optical signal timing module records the start time and the end time of receiving the uplink receiving state signal, and transmits the same to the CPU module;

Step S5: The CPU module compares the time slot allocation information sent by the PON time slot control module with the start time and the end time of the uplink receiving state signal sent by the optical signal timing module, and determines whether the ONT uplink optical link meets the time slot requirement.
The OLT system of claim 6, wherein the OLT time slot control module allocates an uplink time slot for each ONT according to the PON protocol in the step S2.
The method for detecting an abnormal illumination of an ONT by an OLT in the PON system according to claim 6, wherein in the step S4, the optical signal timing module performs a timing function when the trigger signal is valid.
The OLT system of claim 6, wherein the OLT detects an abnormal illuminating of the ONT, wherein in the step S5, the CPU module determines whether the ONT uplink optical link meets the time slot requirement according to the following rules:

When the start time and the end time of the uplink receiving status signal are in the uplink time slot allocated by the ONT, the OLT uplink optical link satisfies the time slot requirement;

When the start time and the end time of the uplink receiving status signal are not completely in the uplink time slot allocated by the ONT, the OLT uplink optical link does not satisfy the time slot requirement.
The OLT system of claim 6, wherein the OLT detects an abnormal illuminating of the ONT, and further includes the step S6: when the ONT uplink optical link does not meet the time slot requirement, the alarm module sends an alarm.