KR101136459B1 - Optical network terminal for fiber to the home system and method for managing state of the optical network terminal - Google Patents

Abstract

The present invention relates to an optical network device (ONU: Optical Network Terminal or ONT: Optical Network Terminal) of a FTTH (Fiber-To-The-Home) system. It is represented by the LED and the presence or absence of an incoming light signal is represented by a red LED, and the overall state of the optical network device is displayed in three colors by the mixed color of the green LED and the red LED. In addition, it reports the abnormality of the optical signal to the host device. Therefore, when opening the optical network device (ONT / ONU) and performing maintenance tasks such as after-sales service, it is possible to immediately determine whether the incoming optical signal is abnormal on the spot through the LED, which shortens the opening time and reduces and maintains the optical network device. The time for maintenance work can be drastically reduced.

ONT, ONU, FTTH, LED, Registration, PON, OLT

Description

OPTICAL NETWORK TERMINAL FOR FIBER TO THE HOME SYSTEM AND METHOD FOR MANAGING STATE OF THE OPTICAL NETWORK TERMINAL}

The present invention relates to an optical network device (ONU: Optical Network Unit or ONT: Optical Network Terminal) of a Fiber-To-The-Home (FTTH) system.

Conventional subscriber networks using copper lines include, for example, digital subscriber lines (xDSL) using telephone lines (where x refers to several other variants of DSL, such as ADSL and VDSL) and cable modem technology using coaxial cables. The conventional subscriber network has a disadvantage in that the bandwidth is limited according to the transmission distance.

Therefore, the only way to overcome the limitation of transmission distance in the conventional subscriber network is to use a single mode fiber (SMF) that provides infinite transmission bandwidth. It is called FTTH (Fiber-To-The-Home) to install subscribers using single-mode fiber as a transmission medium and to send and receive information. At this time, the point-to-multipoint structure is used to reduce the optical fiber that needs to be installed to subscribers, but the passive FTTH consisting of passive devices without active devices / systems is specially used for passive optical subscriber network (PON). Optical Network).

The passive optical subscriber network is an optical line terminal (OLT) installed at a communication operator and starts a passive optical subscriber network, and an optical network device (ONU) installed at a subscriber side in an assembly building or premises to transmit and receive optical signals with the OLT. It includes: Optical Network Uint or ONT: Optical Network Terminal. In the passive optical subscriber network, the OLT and the optical network device (ONU / ONT) are configured in a point-to-multipoint method and use a multiplexing method.

In the passive optical subscriber network as described above, an optical network device (ONU / ONT) is a device that provides a service interface to an end subscriber, and is installed in an assembly building or a premises as described above. This is necessary. Conventionally, after the optical network device is installed in an assembly building or a premises, a separate measuring device is connected to the optical network device to check whether the registration is properly performed in the OLT and whether the optical signal is properly received by the optical network device. Since it is necessary to check, the installer has to carry a lot of equipment, and there is a problem that the test takes a considerable time.

The present invention has been proposed to improve the above problems, and by displaying the registration state of the OLT and the presence or absence of the optical signal in three types of colors, without the need for a separate equipment, It is an object of the present invention to provide an optical network device and a state management method of the optical network device that can easily check the normal operating state of the network device.

Other objects and advantages of the invention will be described below and will be appreciated by the practice of the invention. Further, objects and advantages of the present invention can be realized by the means and the combination shown in the appended claims.

According to an aspect of the present invention for achieving the above object, an optical network device of a fiber-to-the-home (FTTH) system, by comparing the intensity and reference value of the optical signal received from the higher-level equipment of the FTTH system accordingly An optical signal detector for outputting a toggle signal; A controller configured to perform a registration procedure to the upper device according to the connection with the upper device and to output a control signal according to a registration result; And a display unit for displaying a mixed color of the red display means and the green display means, including a red display means turned on / off according to the toggle signal and a green display means turned on / off according to the control signal.

The optical signal detector of the optical network device may output the first toggle signal when the intensity of the optical signal is greater than the first reference value and then output the second toggle signal when the intensity of the optical signal is less than the second reference value.

In addition, the red display means of the display unit may be in an off state upon receiving the first toggle signal and in an on state when receiving the second toggle signal.

The controller may transmit an optical signal error occurrence message to the higher level equipment when the second toggle signal is received after receiving the first toggle signal.

The controller may transmit an optical signal error generation release message to the upper device when the first toggle signal is received after the optical signal error occurrence message is transmitted.

Preferably, the first reference value is larger than the second reference value.

According to another aspect of the present invention for achieving the above object, the state management method of the optical network device of the FTTH system, the registration step of performing a registration procedure with the higher equipment of the FTTH system; A comparison step of comparing the intensity of the optical signal received from the higher level equipment with a reference value; A first on / off step of turning on / off the green display means according to the registration result of the registration step; A second on / off step of turning on / off the red display means according to the comparison result of the comparing step; And a display step of displaying a mixed color of the green display means and the red display means.

The comparing may include generating a first toggle signal when the intensity of the optical signal is greater than a first reference value; And generating a second toggle signal when the intensity of the optical signal is smaller than a second reference value after generating the first toggle signal.

The second on / off step may include: turning off the red display means based on the first toggle signal; And turning on the red display means based on the second toggle signal.

The state management method may further include transmitting an optical signal error occurrence message or an optical signal error release message to the upper device according to the comparison result of the comparing step.

The present invention as described above, when opening the optical network device (ONT / ONU) of the FTTH system and performing maintenance tasks such as A / S, it is possible to immediately determine whether there is an abnormality of the incoming optical signal in the field through the LED, shortening the opening time In addition, it can dramatically reduce the time required for optical network device failure and maintenance, thereby improving productivity, reducing the cost of investment by reducing unnecessary replacement work, and preempting customer complaints with alarm messages. Take action.

The foregoing and other objects, features and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings, in which: There will be. In the following description, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail. Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

1 is a diagram showing the configuration of an optical network device according to an embodiment of the present invention.

As shown in FIG. 1, the optical network device 100 according to the present embodiment includes an optical transceiver 110, a PON chip 130, a red LED 140, and a green LED 150. do.

The optical transceiver 110 is responsible for processing a physical media dependent (PMD) sublayer of a passive optical subscriber network (PON), and photoelectrically converts an optical signal received from an optical line terminal (OLT). In addition, the signal to be transmitted to the OLT is optically converted and transmitted to the OLT.

In addition, the optical transceiver 110 has a Loss-Of-Signal (LOS) or Signal-Detect (SD) function and transmits a toggle signal (high or low) according to a detection result of the optical signal received from the OLT. Outputs 130 and the red LED (140). That is, the optical transceiver 110 includes an optical signal detection module that detects an optical signal received from the OLT and outputs a toggle signal accordingly.

The optical signal detection module may use two reference values as a reference value for detecting the optical signal and outputting a toggle signal. The first reference value is a reference value for outputting a high signal, and the second reference value is a reference value for outputting a low signal.

The optical signal detection module compares the intensity of the optical signal received from the OLT with the first reference value when power is supplied to the optical network device 100, and generates a high signal when the signal intensity exceeds the first reference value. Output In addition, the optical signal detection module outputs a high signal and then compares the intensity of the optical signal received from the OLT with the second reference value, and outputs a low signal when the signal intensity is smaller than the second reference value.

Preferably, the first reference value differs from the second reference value by about 2 dBm or more, and the first reference value is larger than the second reference value.

Alternatively, the optical signal detection module may use only one reference value as a reference value for detecting the optical signal and outputting a toggle signal. In this case, the optical signal detection module outputs a high signal when the intensity of the optical signal received from the OLT exceeds the reference value when power is applied to the optical network device 100, and outputs a high signal after outputting the high signal. When the signal strength is smaller than the reference value, a low signal is output.

It is more preferable to use two reference values than to use one reference value. By using two reference values and increasing the reference values used in the opening process, the operation can be performed in a more stable state at the time of opening than when operating the optical network device 100.

The PON chip 130 is a control means for controlling the overall operation of the optical network device 100. When power is applied to the optical network device 100, the PON chip 130 performs a registration procedure with the OLT through the optical transceiver 110. do. In this case, in order to perform the registration procedure for the OLT, the optical signal received from the OLT should have a signal strength equal to or greater than a predetermined reference value (referred to as a third reference value in this embodiment).

When the registration procedure for the OLT is completed, that is, when the optical signal received from the OLT indicates a signal strength equal to or greater than a third reference value, the PON chip 130 outputs the control signal according to the green LED 150 to output the green LED 150. ) To ON and output green light. Here, the third reference value is smaller than the first and second reference values. Registration may require only a minimum optical signal, but service operation requires a stable optical signal.

The PON chip 130 continuously registers the optical signal by checking the optical signal even after the OLT and the registration process are completed. When the intensity of the optical signal received in this process becomes smaller than the third reference value, the registration state cannot be maintained. Accordingly, the daughter PON chip 130 outputs the control signal according to the green LED 150 to output the green LED 150. ) To OFF.

In addition, the PON chip 130 receives a toggle signal according to the optical signal detection result from the optical transceiver 110 through a general purpose input-output (GPIO) pin, and based on the received toggle signal, It determines whether there is an error and sends an optical signal error occurrence and release message to the OLT.

Specifically, when the PON chip 130 receives a low signal after receiving a high signal as a toggle signal according to the optical signal detection result from the optical transceiver 110, the PON chip 130 has an abnormality in the optical signal. It is determined that the optical signal abnormality occurrence message to the OLT. In addition, the PON chip 130 determines that the optical signal is normally received when the high signal is received as the toggle signal according to the optical signal detection result from the optical transceiver 110 after transmitting the optical signal error occurrence message. The OLT signal is sent to OLT.

On the other hand, the red LED 140, when the power is applied to the optical network device 100 is basically turned on to output a red light, if the toggle signal received from the optical signal detection module is a high signal (OFF) OFF It enters a state and stops light emission. In addition, the red LED 140 is turned on when the toggle signal received from the optical signal detection module is a low signal (low) to output a red light. That is, when the red LED 140 emits light, it means that there is an abnormality in the light signal, and when the light emission is stopped, the light signal is in a normal state.

When the power is applied to the optical network device 100, the green LED 150 is turned off by default, and is turned on / off according to a control signal received from the PON chip 130 to emit green light or stop emitting light. do. When the green LED 150 emits light, it indicates that the optical network device 100 is normally registered in the OLT. When the green LED 150 stops emitting light, it means that registration is not performed normally.

The red LED 140 and the green LED 150 as described above are disposed in close proximity to the light emitted from the mixture is displayed to the outside. Therefore, when both red and green light emitting, orange is displayed on the outside, and if either one does not emit light, red or green is displayed on the outside. That is, the state of the optical network device 110 is displayed by dividing it into three colors of red, orange, and green. The state of the optical network device 110 according to each color is summarized in the following [Table 1]. However, the present invention is not necessarily limited thereto, and the red LED 140 and the green LED 150 may be displayed alone.

Red LED Green LED Mixed color condition ○ × Red Optical signal abnormal, unregistered ○ ○ orange color Optical signal abnormal, registration status × ○ green Optical signal normal, registration status

FIG. 2 is a state diagram of an optical network device according to an embodiment of the present invention, in which the horizontal axis represents reception sensitivity of an optical signal, and A, B, C, and D represent states of the optical network device.

In the state diagram of FIG. 2, the state at the time of applying power to the optical network device 100 and connecting the optical cable changes from D → C → A. That is, when power is supplied to the optical network device 100 and the optical cable is not connected, the intensity of the optical signal is close to -∞, and thus only the red LED 140 emits light, and the mixed color is red. Then, when the optical cable is connected and the intensity of the optical signal is improved to -34.48 ㏈m or more (that is, proceeding from D to C), the green LED 150 emits light and the mixed color becomes orange. Then, when the intensity of the optical signal becomes more than -24.92 dBm (ie, proceeds from C to A), the red LED 140 stops emitting light, and the mixed color becomes green.

In summary, in the D state, the optical network device 100 displays an orange color while completing the registration procedure in the OLT. This state means that the registration is normally performed, but the optical signal is not normally received. Subsequently, when the optical signal is normally received and goes to the A state, in the optical network device 100, the red LED 140 stops emitting light and only green is displayed. This state is normally registered and the optical signal is normally received. It means that there is.

On the other hand, in the state diagram of Fig. 2, when the optical network device 100 operates normally but the state changes, the state changes from A to B to D. That is, when the registration of the optical network device 100 is normally performed and the optical signal is also normally received, when the intensity of the optical signal is weakened, that is, weaker than -26.91m, the optical network device 100 is in the B state. While proceeding to the state D in the red LED 140 starts to emit light. Therefore, the mixed color of the optical network device 100 becomes orange. That is, it is a registered state, but it shows that there is an abnormality in an optical signal. Thereafter, when the intensity of the optical signal becomes weaker and falls below the D point, the green LED 150 of the optical network device 100 stops emitting light and only the red LED 140 emits light. Therefore, the mixed color of the optical network device 100 becomes red. That is, it is not a registration state and shows that there is an abnormality in an optical signal.

In the above description, when the state changes from D → C → A and when the state changes from A → B → D, the point at which the green LED 150 turns ON / OFF is the D point (that is, -34.48 m). Same as each other, the point where the red LED 140 is ON / OFF are different. When the state changed from D → C → A, the red LED 140 changed from ON state to OFF state at A point, and changed from OFF state to ON state at B point when A → B → D state changed. This is to open the operation in a more stable situation when opening the power supply to the optical network device 100. As described above, the first reference value means A point, the second reference value means B point, and the third reference value means D point.

In the description with reference to FIG. 2, the case where the first reference value and the second reference value are different as described above has been described. However, the first reference value and the second reference value may be the same. At this time, the orange area form of a state diagram becomes a rectangle. In FIG. 2, although the ON / OFF switch point of the red LED 140 is A point at the time of opening, although it is different from B point at the time of operation, you may make the point the same. However, for stable opening operation upon initial power-up, it is desirable to have different point points and to have a margin of reception sensitivity between each point.

3 is a flowchart illustrating an operation process of an optical network device according to an embodiment of the present invention, and describes an operation of an initial opening process.

As shown in FIG. 3, when power is applied to the optical network device 100 (S301), the red LED 140 of the optical network device 100 is turned on as a default state to emit red light, and the green LED. 150 is turned off as a default state and does not emit light (S303). Therefore, the LED color displayed on the optical network device 100 is red.

Meanwhile, when the optical cable is connected to the optical network device 100 (S305), the PON chip 130, which is a control means of the optical network device 100, performs a registration procedure through the connected optical cable (S307). In order to perform the registration procedure with the higher-level equipment, the optical signal received through the optical cable should have a minimum signal strength. Here, it defines as a 3rd reference value. When the intensity of the received optical signal is greater than or equal to the third reference value, the optical network device 100 may complete registration with the OLT. The PON chip 130 periodically performs this registration state maintenance operation while power is applied.

As such, when the registration procedure is completed with the OLT, which is the upper device, the PON chip 130 of the optical network device 100 outputs a control signal to the green LED 150 to turn on the green LED 150 (S309). ). Therefore, the red of the red LED 140 and the green of the green LED 150 which are turned on when the power is applied are mixed to display an orange color on the outside of the optical network device 100.

On the other hand, the optical signal detection module of the optical network device 100 detects the optical signal after the power is applied and compares the intensity of the received optical signal with the first reference value to determine whether the signal strength is greater than the first reference value (S311). When the signal strength becomes larger than the first reference value, a high signal is output as a toggle signal, and the output high signal is transmitted to the PON chip 130 and the red LED 140.

Accordingly, the red LED 140 stops light emission according to the high signal (S313). As the red LED 140 stops emitting light, only the green LED 150 emits light, and therefore, the color of the LED becomes green when viewed from the outside of the optical network device 100. In other words, registration is made and the optical signal is also normally received.

4 is a flowchart illustrating an operation process of an optical network device according to another embodiment of the present invention, and describes the operation of the operation process after opening.

Referring to FIG. 4, when the opening procedure is performed and the optical signal is normally received as described with reference to FIG. 3, the optical signal detection module of the optical network apparatus 100 detects an optical signal received from an OLT, which is a higher level equipment. Continually. That is, the optical signal detection module detects the optical signal and continuously checks whether the intensity of the optical signal is smaller than the second reference value (S401). Here, the second reference value is smaller than the first reference value in the opening process described with reference to FIG. 3.

When the intensity of the optical signal is smaller than the second reference value, the optical signal detection module outputs a low signal to the PON chip 130 and the red LED 140 as a toggle signal. Therefore, the red LED 140 is turned on to output a red light (S403), when viewed from the outside of the optical network device 100 is mixed with the green light of the green LED (150) and looks orange. In other words, the registration is normal, but there is a problem with the optical signal. At this time, the PON chip 130 of the optical network device 100 transmits an optical signal error occurrence message to the OLT to report the fact that the optical signal has an abnormality to the OLT, which is an abnormality, when the low signal is received.

When the intensity of the optical signal is smaller than the second reference value as described above, the optical signal detection module continuously checks whether the intensity of the optical signal is greater than the second reference value or less than the third reference value (S405 and S407).

If the intensity of the optical signal is again greater than the second reference value, the process proceeds to step S313 of FIG. 3 and outputs a high signal to the PON chip 130 and the red LED 140. Accordingly, the red LED 140 is turned off and only the green LED 150 displays green light, so that the green LED 150 is also seen as green light from the outside of the optical network device 100. At this time, the PON chip 130 determines that the optical signal abnormality is solved based on receiving the low signal and then receiving the high signal again, and transmits the optical signal abnormality release message to the OLT.

On the other hand, when the intensity of the optical signal does not become larger than the second reference value but rather smaller than the third reference value, the PON chip 130, which is a control means of the optical network apparatus 100, cannot maintain the registration state with the OLT, which is the upper equipment. Accordingly, the PON chip 130 outputs the control signal according to the green LED 150, and the green LED 150 is turned off and does not output green light (S409). Accordingly, only the red LED 140 outputs light, so that the orange color turns red when viewed from the outside of the optical network device 100.

In this way, even after the intensity of the optical signal becomes smaller than the third reference value, the PON chip 130 of the optical network device 100 continues to attempt the registration procedure with the OLT. When the intensity of the optical signal becomes larger than the third reference value, After completing the registration procedure, the control signal is output to the green LED 150. The green LED 150 is turned on and is mixed with the red of the red LED 140 so that an orange color is visible when viewed from the outside of the optical network device 100 (S413). That is, the registration is normally performed, but it indicates that there is an error in the optical signal.

As described above, the method of the present invention may be implemented as a program and stored in a recording medium (CD-ROM, RAM, ROM, floppy disk, hard disk, magneto-optical disk, etc.) in a computer-readable form.

While the specification contains many features, such features should not be construed as limiting the scope of the invention or the scope of the claims. Also, the features described in the individual embodiments herein can be implemented in combination in a single embodiment. Conversely, various features described herein in a single embodiment may be implemented in various embodiments individually or in a suitable subcombination.

It is to be understood that, although the operations have been described in a particular order in the figures, it should be understood that such operations are performed in a particular order as shown, or that a series of sequential orders, or all described operations, . In some circumstances, multitasking and parallel processing may be advantageous. In addition, it should be understood that the division of various system components in the above-described embodiments does not require such division in all embodiments. The above-described program components and systems can generally be implemented as a single software product or as a package in multiple software products.

The present invention described above is capable of various substitutions, modifications, and changes without departing from the technical spirit of the present invention for those skilled in the art to which the present invention pertains. It is not limited by the drawings.

The following drawings, which are attached to this specification, illustrate preferred embodiments of the present invention, and together with the detailed description of the present invention serve to further understand the technical spirit of the present invention, the present invention includes matters described in such drawings. It should not be construed as limited to.

1 is a diagram showing the configuration of an optical network device according to an embodiment of the present invention.

2 is a state diagram of an optical network device according to an embodiment of the present invention.

3 is a flowchart illustrating an operation process of an optical network device according to an embodiment of the present invention.

4 is a flowchart illustrating an operation process of an optical network device according to another embodiment of the present invention.

Claims (12)

In the optical network device of a Fiber-To-The-Home (FTTH) system, An optical signal detector for comparing an intensity and a reference value of the optical signal received from higher-level equipment of the FTTH system and outputting a toggle signal according thereto; A controller configured to perform a registration procedure to the upper device according to the connection with the upper device and to output a control signal according to a registration result; And And a display unit for displaying a mixed color of the red display means and the green display means, including a red display means turned on / off in response to the toggle signal and a green display means turned on / off in response to the control signal. The method of claim 1, The optical signal detector, And outputting the first toggle signal when the intensity of the optical signal is greater than the first reference value and outputting the second toggle signal when the intensity of the optical signal is less than the second reference value. The method of claim 2, The red display means of the display unit, And an off state upon receipt of the first toggle signal and an on state upon receipt of the second toggle signal. The method of claim 2, The control unit, And receiving the second toggle signal after receiving the first toggle signal, and transmitting an optical signal error occurrence message to the upper device. The method of claim 4, wherein The control unit, And receiving the first toggle signal after transmitting the optical signal error occurrence message, transmitting the optical signal error occurrence release message to the upper device. The method according to any one of claims 2 to 5, And wherein the first reference value is greater than the second reference value. The method according to any one of claims 2 to 5, And the first reference value and the second reference value are the same. In the state management method of an optical network device of a fiber-to-the-home (FTTH) system, A registration step of performing a registration procedure with higher equipment of the FTTH system; A comparison step of comparing the intensity of the optical signal received from the higher level equipment with a reference value; A first on / off step of turning on / off the green display means according to the registration result of the registration step; A second on / off step of turning on / off the red display means according to the comparison result of the comparing step; And And a display step of displaying a mixed color of the green display means and the red display means. The method of claim 8, The comparing step, Generating a first toggle signal when the intensity of the optical signal is greater than a first reference value; And And generating a second toggle signal when the intensity of the optical signal is smaller than a second reference value after the generation of the first toggle signal. The method of claim 9, The second on / off step, Turning off the red display means based on the first toggle signal; And And turning on the red display means on the basis of the second toggle signal. 11. The method according to claim 9 or 10, And wherein the first reference value is greater than the second reference value. The method of claim 8, And transmitting an optical signal error occurrence message or an optical signal error release message to the upper device according to the comparison result of the comparison step.

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