JP2012156954A - Station side device, home side device, and communication system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a station side device, a home side device, and a communication system, capable of reducing power consumption by properly controlling power supply at the station side device.SOLUTION: The station side device for transmitting/receiving optical signal from one or more home side devices includes state information acquiring parts 36 and 22 for acquiring the state information representing a state of each home side device, and a power control part 51 which, in a case the state information acquired by the state information acquiring parts 36 and 22 shows a non-communication state where there is not any home side device that can communicate with the station side device, stops power supply to an object circuit at the station side device other than the state information acquiring part 36 and 22.

Description

  The present invention relates to a station-side device, a home-side device, and a communication system, and more particularly, to a station-side device, a home-side device, and a communication system that reduce power consumption of the station-side device.

  In recent years, the Internet has become widespread, and users can access various information on sites operated in various parts of the world and obtain the information. Along with this, devices capable of broadband access such as ADSL (Asymmetric Digital Subscriber Line) and FTTH (Fiber To The Home) are rapidly spreading.

  In IEEE Std 802.3ah (registered trademark) -2004 (non-patent document 1), a plurality of home side devices (ONU: Optical Network Unit) share an optical communication line, and a station side device (OLT: Optical Line Terminal). One method of a passive optical network (PON), which is a medium-sharing communication that performs data transmission with the network, is disclosed. That is, EPON (Ethernet (registered trademark) PON) in which all information is communicated in the form of an Ethernet (registered trademark) frame, including user information passing through the PON and control information for managing and operating the PON, and EPON An access control protocol (MPCP (Multi-Point Control Protocol)) and an OAM (Operations Administration and Maintenance) protocol are defined. By exchanging MPCP frames between the station side device and the home side device, the home side device joins and leaves, and uplink access multiplexing control is performed.

  As a next-generation technology of GE-PON, which is an EPON that realizes a communication speed of 1 gigabit / second, 10G-EPON standardized as IEEE 802.3av (registered trademark) -2009, that is, a communication speed of 10 gigabit / second. Even in EPON equivalent to seconds, the access control protocol is predicated on MPCP.

  As a technique for reducing the power consumption of the home device in such a PON system, for example, Japanese Patent Application Laid-Open No. 2010-1114830 (Patent Document 1) discloses the following configuration. That is, in a PON optical communication system that performs optical communication between a station-side device and a plurality of home-side devices via an optical branching unit, the transmission unit of the station-side device sequentially transmits user frames to each home-side device. And a power saving mode control unit. The power saving mode control unit transmits an uplink bandwidth allocation control frame to the home side device to the home side device in which the user frame to be transmitted in the downlink buffer unit is empty, and then the other home side device. A power saving mode setting frame describing a power saving mode time set to a time shorter than one round time until the uplink side bandwidth allocation control frame is transmitted to the home side apparatus is transmitted. The PON receiving unit of the home side device has a frame analysis unit that analyzes a frame addressed to the local station received from the station side device, and the frame analysis unit receives the power saving mode setting frame. The PON receiving unit is set in the power saving mode for the power saving mode time described in the power saving mode setting frame.

IEEE Std 802.3ah (registered trademark) -2004

JP 2010-1114830 A

  Patent Document 1 discloses a configuration in which when there is no frame to be transmitted to a home side device, the home side device is set in a power saving mode to reduce power consumption. On the other hand, a technique for appropriately controlling power supply and reducing power consumption is also desired in the station side device.

  This invention was made in order to solve the above-mentioned subject, The objective is the station side apparatus which can reduce power consumption by controlling the electric power supply in a station side apparatus appropriately, and the house side An apparatus and a communication system are provided.

  In order to solve the above problems, a station-side device according to an aspect of the present invention is a station-side device for transmitting / receiving an optical signal to / from one or more home-side devices, and transmits the optical signal to / from the home-side device. An optical transmission / reception unit for transmitting / receiving, a state information acquisition unit for acquiring state information indicating a state of the home side device, and the state information acquired by the state information acquisition unit communicate with the station side device. A power control unit for performing control to stop power supply to the target circuit in the station side device other than the state information acquisition unit when indicating that the possible home side device does not exist With.

  With such a configuration, it is possible to appropriately control power supply in accordance with the presence / absence of a home device that can communicate with itself. In addition, the station-side device automatically stops power supply, so that when there is no home-side device to communicate, the station-side device can be used without removing the board mounted on the station-side device. Power consumption can be reduced. Therefore, the power consumption can be reduced by appropriately controlling the power supply in the station side device.

  Preferably, the station side device further includes a power switching unit for receiving power and switching whether or not to supply the power to the optical transmission / reception unit, and the power control unit includes the state information acquisition unit When the state information acquired by the above indicates that there is no communication, the power switching unit is controlled to stop power supply to the optical transmission / reception unit.

  As described above, the configuration in which the power supply to the optical transmission / reception unit with large power consumption is stopped can efficiently reduce the power consumption of the station side device with a simple configuration.

  Preferably, the state information acquisition unit includes an optical input detection unit for detecting an optical signal from the home-side device, and the power control unit includes the state information acquired by the state information acquisition unit as the state information. When indicating that there is no communication state, control is further performed to stop power supply to one or more circuits in the state information acquisition unit other than the optical input detection unit.

  Thus, in order to detect whether or not the home-side device is activated by the configuration of providing the optical input detection unit for detecting the upstream optical signal from the home-side device and detecting the transition to the communicable state In addition, a control frame such as a discovery message can be transmitted from the station side device to the home side device, and power supply to a part that processes and waits for the arrival of a discovery response from the home side device can be stopped. For this reason, the power consumption in the station side device can be further reduced.

  Preferably, the optical transmission / reception unit transmits / receives an optical signal via an optical line common to the home-side device, and the state information acquisition unit acquires the state information indicating the non-communication state, and then the optical line. When the level of the optical signal received from the mobile station is detected and the detected level is equal to or higher than a predetermined threshold value, the state shifts from the no-communication state to the communicable state where the home-side device capable of communicating with the station-side device exists. If it is determined that the state information acquisition unit has transitioned to the communicable state, the power control unit performs control to resume power supply to the target circuit.

  As described above, the configuration in which the level of the upstream optical signal received from the common optical line among the home-side devices is detected, so even if the activation notification is simultaneously transmitted from the plurality of home-side devices to the station-side device, the station-side device Therefore, it is possible to reliably detect the activation of the home-side apparatus with a simple configuration.

  In order to solve the above problems, a home-side apparatus according to an aspect of the present invention includes a communication system including one or a plurality of home-side devices and a station-side device for transmitting and receiving optical signals to and from each home-side device. In the above-mentioned home-side device, the station-side device acquires a communication information transmitting unit for periodically transmitting communication information to the home-side device, and status information indicating the status of the home-side device If the state information acquired by the state information acquisition unit and the state information acquisition unit indicate that the home side device capable of communicating with the station side device does not exist, the state information A power control unit for performing control to stop power supply to the target circuit in the station side device other than the information acquisition unit, the home side device receiving the communication information from the station side device A communication information receiver and a predetermined When the communication information is not received by the communication information receiving unit for a predetermined time from the timing, the communication information receiving unit includes an activation notification transmitting unit for transmitting an activation notification to the station side device, and the power control unit supplies the power supply. In the stopped state, when the activation notification is received from the activation notification transmitting unit, the power supply to the target circuit in the station side device is resumed.

  In this way, the configuration in which the activation notification is autonomously transmitted from the home side device makes the transition to the power saving mode, and communication information such as a discovery message for confirming the existence of a communicable home side device is not transmitted. It is possible to cause the station side device to detect that the home side device is activated. Therefore, the power consumption can be reduced by appropriately controlling the power supply in the station side device.

  In order to solve the above problems, a communication system according to an aspect of the present invention includes one or a plurality of home-side devices and station-side devices for transmitting and receiving optical signals to and from each home-side device. The side device has a state information acquisition unit for acquiring state information indicating the state of the home side device, and the home side on which the state information acquired by the state information acquisition unit can communicate with the station side device A power control unit for performing control to stop power supply to the target circuit in the station side device other than the state information acquisition unit when indicating that the device is in a non-communication state.

  With such a configuration, it is possible to appropriately control power supply in accordance with the presence / absence of a home device that can communicate with itself. In addition, the station-side device automatically stops power supply, so that when there is no home-side device to communicate, the station-side device can be used without removing the board mounted on the station-side device. Power consumption can be reduced. Therefore, the power consumption can be reduced by appropriately controlling the power supply in the station side device.

  A communication system according to another aspect of the present invention includes one or a plurality of home-side devices and station-side devices for transmitting and receiving optical signals to and from each home-side device. A communication information transmission unit for periodically transmitting communication information to a side device, a state information acquisition unit for acquiring state information indicating the state of the home side device, and the state information acquired by the state information acquisition unit When the status information indicates that the home device that can communicate with the station side device does not exist, the power supply to the target circuit in the station side device other than the state information acquisition unit is performed. A power control unit for performing control to stop, wherein the home-side device includes a communication information receiving unit for receiving the communication information from the station-side device, and the communication information receiving unit for a predetermined time from a predetermined timing. In the above communication information Is not received, the activation notification transmission unit for transmitting the activation notification to the station side device, the power control unit from the activation notification transmission unit in the state of stopping the power supply When the notification is received, the power supply to the target circuit in the station side device is resumed.

  With such a configuration, it is possible to appropriately control power supply in the station-side device according to the presence / absence of a home-side device that can communicate with itself. In addition, the station-side device automatically stops power supply, so that when there is no home-side device to communicate, the station-side device can be used without removing the board mounted on the station-side device. Power consumption can be reduced. In addition, for the station side device that has transitioned to the power saving mode and confirmed the existence of a communicable home side device by transmitting the activation notification autonomously from the home side device. It is possible to detect that the home device has been activated. Therefore, the power consumption can be reduced by appropriately controlling the power supply in the station side device.

  According to the present invention, it is possible to reduce power consumption by appropriately controlling the power supply in the station side device.

It is a block diagram which shows schematic structure of the PON system which concerns on embodiment of this invention. It is a figure which shows the structure of OSU in the station side apparatus which concerns on embodiment of this invention. It is a figure which shows the structure of the home side apparatus which concerns on embodiment of this invention. It is a figure which shows the flow of the data between the station side apparatus in a PON system which concerns on embodiment of this invention, and a home side apparatus, and the sequence of the electric power control in a station side apparatus.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals and description thereof will not be repeated.

[Configuration and basic operation]
FIG. 1 is a block diagram showing a schematic configuration of a PON system according to an embodiment of the present invention.

  Referring to FIG. 1, a PON system 301 includes a station-side device 201, N PON lines 1 to N (203-1 to 203-N), which are optical fibers, and N optical couplers 204-1 to 204-1. 204-N and a plurality of home-side devices (ONUs) 202. The station apparatus 201 includes optical line units (hereinafter also referred to as OSUs (Optical Subscriber Units)) 1 to N (12-1 to 12-N) and an overall control unit 11 that performs overall control of the station apparatus 201. Including. Here, N is an integer of 1 or more. In addition, a direction from the home side device to the host network (hereinafter also referred to as “uplink”) is referred to as an uplink direction, and a direction from the uplink to the home side device is referred to as a downlink direction.

  For example, in the PON system 301, each PON line corresponds to GEPON, which is an EPON that realizes a communication speed of 1 gigabit / second, and the uplink is Ethernet (registered trademark) that realizes a communication speed of 10 gigabit / second. Correspond. In addition, the MPCP frame performs ONU registration, withdrawal, bandwidth allocation to the ONU, bandwidth request from the ONU, sleep (operation stop) instruction to the ONU, and the like.

  The station apparatus 201 accommodates a plurality of PON lines corresponding to GEPON. One or a plurality of ONUs are connected to one PON line. The station-side apparatus 201 transmits data from these PON lines to a plurality of communication lines in the uplink. Further, the station side device 201 transmits data from each communication line in the uplink to each home side device in the corresponding PON line. Further, the station side device 201 allocates the upstream band and the downstream band of the PON line to each home side device. For example, the upstream optical signal from each home device to the station device 201 is a burst signal, and the downstream optical signal from the station device 201 to each home device is a continuous signal.

  More specifically, the station-side apparatus 201 is connected to N PON lines 1 to N, and terminates the N PON lines. Each OSU is provided corresponding to a PON line, and transmits / receives a frame to / from one or more ONUs connected to the corresponding PON line. The PON lines 1 to N are connected to the optical couplers 204-1 to 204-N, respectively, and are connected to the respective ONUs 202 through these optical couplers.

  FIG. 2 is a diagram showing the configuration of the OSU in the station side apparatus according to the embodiment of the present invention.

  Referring to FIG. 2, OSU 12 includes a power control unit 51, an optical input detection unit (state information acquisition unit) 52, a power switching unit 53, an uplink IF (Interface) unit 31, and a control IF unit 32. A reception processing unit 33, a transmission processing unit 34, a PON transmission / reception unit (optical transmission / reception unit) 35, a PON control unit (state information acquisition unit, communication information transmission unit) 36, a FIFO 37 for storing upstream frames, FIFO 38 for storing frames. Each unit and each circuit in the OSU 12 may be mounted on a single substrate or may be separately mounted on a plurality of substrates.

  The PON transmission / reception unit 35 transmits / receives optical signals to / from each ONU via a common PON line. That is, the PON transmission / reception unit 35 is connected to one optical fiber that is a PON line as a starting point on the master station side of the PON line. The PON transmitter / receiver 35 receives an upstream optical signal of a specific wavelength, for example, a 1310 nm band, and converts it into an electrical signal so that bidirectional communication can be performed with each ONU via the optical fiber, and then converts it into an electrical signal. In addition to outputting, the electrical signal received from the transmission processing unit 34 is converted into a downstream optical signal of another wavelength and transmitted. For example, the PON transmission / reception unit 35 converts a 1 Gbps electrical signal received from the transmission processing unit 34 into a downstream optical signal in the 1490 nm band and transmits the converted signal.

  The reception processing unit 33 reconstructs a frame from the electrical signal received from the PON transmission / reception unit 35 and distributes the frame to the PON control unit 36 or the FIFO 37 according to the type of the frame. Specifically, the data frame is output to the FIFO 37 and the control frame is output to the PON control unit 36.

  The uplink IF unit 31 outputs the uplink frame stored in the FIFO 37 to the uplink. Further, upon receiving a frame from the uplink, the uplink IF unit 31 outputs the frame to the FIFO 38 when the frame is a normal data frame, and outputs the frame to the PON control unit 36 when the frame is a control frame. To do.

  When receiving the control frame from the PON control unit 36, the uplink IF unit 31 outputs the control frame to the uplink in preference to the frame from the FIFO 37 between the frame sequences from the FIFO 37.

  When the FIFO 38 or the PON control unit 36 has a frame to be transmitted, the transmission processing unit 34 receives the frame according to the priority order and outputs it to the PON transmission / reception unit 35.

  The PON control unit 36 performs station-side processing related to control and management of the PON line such as MPCP and OAM. That is, by exchanging MPCP messages and OAM messages with each ONU connected to the PON line, upstream access control including ONU registration, withdrawal and upstream bandwidth allocation, downstream access control including downstream bandwidth allocation, and Performs ONU operation management including sleep instructions to the ONU.

  The control IF unit 32 sets the uplink IF unit 31, the reception processing unit 33, the transmission processing unit 34, and the PON control unit 36 based on an instruction from the overall control unit 11, and sets the status of each unit. Notify the overall control unit 11. Further, when an abnormality occurs in each of these units, the state of the unit in which the abnormality has occurred is notified to the overall control unit 11 without depending on an instruction from the overall control unit 11. Setting and status notification to the PON transceiver 35 are performed via the reception processor 33.

  The optical input detection unit 52 detects the level of the upstream optical signal from the PON line, for example, as status information indicating the status of each ONU.

  The power switching unit 53 is, for example, a switch, and switches whether to supply the power supply voltage VCC to each circuit in the OSU other than the optical input detection unit 52, for example, the PON transmission / reception unit 35, upon receiving power, that is, the power supply voltage VCC.

  The power control unit 51 outputs a control signal to the power switching unit 53 to control whether the power switching unit 53 supplies power to the PON transmission / reception unit 35.

  FIG. 3 is a diagram showing the configuration of the home-side apparatus according to the embodiment of the present invention.

  Referring to FIG. 3, home device 202 includes PON port 21, optical reception processing unit 22, buffer memory 23, transmission processing unit 24, UNI port 25, reception processing unit 26, and buffer memory 27. And an optical transmission processing unit 28 and a control unit (communication information receiving unit, activation notification transmitting unit) 29.

  The optical reception processing unit 22 receives the downstream optical signal transmitted from the station side device 201 via the PON port 21, converts it into an electrical signal, reconstructs the frame from the electrical signal, and according to the type of the frame The frame is distributed to the control unit 29 or the transmission processing unit 24 via the buffer memory 23. Specifically, the optical reception processing unit 22 outputs a data frame to the transmission processing unit 24 and outputs a control frame to the control unit 29.

  The transmission processing unit 24 transmits the data frame received from the optical reception processing unit 22 to a user terminal such as a personal computer (not shown) via the UNI port 25.

  The reception processing unit 26 outputs the data frame received from the user terminal via the UNI port 25 to the optical transmission processing unit 28 via the buffer memory 27.

  The control unit 29 performs home-side processing related to control and management of the PON line such as MPCP and OAM. That is, various controls such as access control are performed by exchanging MPCP messages and OAM messages with the station-side apparatus 201 connected to the PON line. The control unit 29 generates a control frame including various control information and outputs it to the optical transmission processing unit 28 via the buffer memory 27.

  The optical transmission processing unit 28 converts the data frame received from the reception processing unit 26 and the control frame received from the control unit 29 into an optical signal, and transmits the optical signal to the station apparatus 201 via the PON port 21.

[Operation]
Next, operations when the station apparatus according to the embodiment of the present invention performs power control will be described with reference to the drawings.

  FIG. 4 is a diagram showing a data flow between the station side device and the home side device in the PON system according to the embodiment of the present invention, and a power control sequence in the station side device. FIG. 4 describes a sequence for one PON line, that is, a process between one OSU and a plurality of ONUs. A case will be described in which ONUs under the OSU are ONUs 1 to n, that is, ONUs 1 to n are connected to the PON line corresponding to the OSU. In this case, the PON control unit 36 in the OSU registers ONUs 1 to n as communication partners. In the following description, FIGS. 2 and 3 are referred to as appropriate.

  Referring to FIG. 4, first, the PON control unit 36 in the OSU periodically generates a control frame indicating a discovery message and transmits it to the ONUs 1 to n via the transmission processing unit 34 and the PON transmission / reception unit 35 ( Step S1).

  Next, the control unit 29 in the ONUs 1 to n receives a control frame indicating a discovery message from the OSU via the PON port 21, the optical reception processing unit 22, and the buffer memory 23. Then, the control unit 29 generates a control frame indicating a discovery response, and transmits it to the OSU via the buffer memory 27, the optical transmission processing unit 28, and the PON port 21 (step S2).

  Next, the PON control unit 36 in the OSU acquires state information indicating the state of each ONU. More specifically, the PON control unit 36 receives a control frame indicating a discovery response from the ONUs 1 to n via the PON transmission / reception unit 35 and the reception processing unit 33, and among the registered ONUs 1 to n, its own OSU. It confirms that it is in a communicable state where there is an ONU communicable with (step S3).

  In this case, the PON control unit 36 outputs, for example, a logic high level signal indicating that communication is possible to the power control unit 51. Further, the optical input detection unit 52 outputs, for example, a logic high level signal indicating a state in which the upstream optical signal is received from the corresponding PON line, to the power control unit 51. Then, power control unit 51 outputs, for example, a logic high level signal indicating an instruction to supply power to PON transmission / reception unit 35 to power switching unit 53. Thereby, the power switching unit 53 outputs the power supply voltage VCC to the PON transmitting / receiving unit 35.

  Next, when a predetermined time has elapsed since the last transmission of the control frame indicating the discovery message, the PON control unit 36 generates a control frame indicating the discovery message and transmits it again to the ONUs 1 to n (step S4).

  Here, it is assumed that the ONUs 1 to n do not transmit a control frame indicating a discovery response to the OSU for some reason, such as when the power is turned off. In this case, the PON control unit 36 in the OSU detects a timeout after a predetermined time has elapsed since the last transmission of the control frame indicating the discovery message. That is, the PON control unit 36 detects that there is no ONU that can communicate with its own OSU among the registered ONUs 1 to n (step S5).

  Here, as a situation in which a no-communication state occurs, in addition to the case where all ONUs have stopped operating accidentally for some reason, for example, an ONU is provided in each room of an apartment house such as a condominium, It can be considered that the ONU is not used in any of the rooms, or that all the rooms are not occupied.

  Next, the power control unit 51 performs control to stop power supply to each circuit in the OSU other than the optical input detection unit 52. That is, the power control unit 51 controls the power switching unit 53 to stop the power supply to the target circuit, for example, the PON transmission / reception unit 35, because the state information acquired by the PON control unit 36 is a no-communication state. To do. Note that the target circuit may be one circuit or a plurality of circuits.

  Specifically, when detecting a timeout, the PON control unit 36 outputs, for example, a logic low level signal indicating that there is no communication state to the power control unit 51. Further, the optical input detection unit 52 outputs, for example, a logic low level signal indicating that the upstream optical signal is not received from the corresponding PON line to the power control unit 51. Then, the power control unit 51 outputs, for example, a logic low level signal indicating an instruction to stop power supply to the PON transmission / reception unit 35 to the power switching unit 53. As a result, the power switching unit 53 stops outputting the power supply voltage VCC to the PON transmitting / receiving unit 35. At this time, the control frame indicating the discovery message is not transmitted from the OSU to the ONUs 1 to n (step S6).

  In the PON system in which the upstream optical signal from each ONU arrives intermittently in the station side device, the power control unit 51 outputs a logic high level signal indicating that communication is possible from the PON control unit 36. In the case where the signal is received, the logic high level signal indicating the instruction to supply power to the PON transceiver 35 is output to the power switching unit 53 regardless of the logic level of the signal received from the optical input detection unit 52. It may be. In other words, the power control unit 51 is configured to validate the signal from the optical input detection unit 52 in a state where it receives a logic low level signal indicating that there is no communication from the PON control unit 36. Good.

  Next, for example, it is assumed that the ONU 1 is powered on and the ONU 1 is activated (step S7).

  Next, when the control unit 29 in the ONU 1 cannot receive a control frame indicating a discovery message for a predetermined time from a predetermined timing, for example, from startup, the control unit 29 transmits a startup notification to the OSU. That is, if a control frame indicating a discovery message does not arrive from the OSU even after a predetermined time has elapsed since activation, the ONU 1 generates a control frame indicating activation notification and transmits it to the OSU (step S8). S9).

  Next, the optical input detection unit 52 in the OSU receives the control frame indicating the activation notification from the ONU 1 and detects that the OSU has transitioned to a communicable state where there is an ONU that can communicate with its own OSU. For example, the optical input detection unit 52 detects the level of the upstream optical signal received from the PON line after the PON transmission / reception unit 36 acquires the state information indicating the non-communication state, and the detected level is equal to or higher than a predetermined threshold. If there is, it is determined that the communication state has changed from the no-communication state.

  Then, after stopping the power supply, the power control unit 51 receives the activation notification from the control unit 29, and thus restarts the power supply to each circuit in the OSU. That is, since the power control unit 51 determines that the optical input detection unit 52 has transitioned to the communicable state, the power control unit 51 controls the power switching unit 53 to restart the power supply to the PON transmission / reception unit 35, for example.

  Specifically, the PON control unit 36 continues to output a logic low level signal indicating that there is no communication to the power control unit 51. On the other hand, the optical input detection unit 52 detects the activation notification from the corresponding PON line, and outputs a logic high level signal indicating that communication is possible to the power control unit 51. Then, the power control unit 51 outputs a logic high level signal indicating an instruction to supply power to the PON transmission / reception unit 35 to the power switching unit 53. As a result, the power switching unit 53 resumes outputting the power supply voltage VCC to the PON transmitting / receiving unit 35 (step S10).

  Then, after the power supply to the PON transmission / reception unit 35 is resumed, the PON control unit 36 resumes discovery message transmission to each ONU and performs processing for establishing a link with the ONU 1.

  The power control unit 51 may be configured to stop power supply to the optical input detection unit 52 in a communicable state. Thereby, in a communicable state, power consumption by the optical input detection unit 52 can be prevented, and a decrease in the reception level of the upstream optical signal in the PON transmission / reception unit 35 can be prevented.

  As described above, in the station side apparatus according to the embodiment of the present invention, the PON control unit 36 acquires state information indicating the state of each ONU. When the power control unit 51 indicates that the state information acquired by the PON control unit 36 is a non-communication state where there is no ONU that can communicate with its own OSU, the power control unit 51 other than the light input detection unit 52 Control is performed to stop power supply to one or more circuits in the OSU, for example, the PON transceiver unit 35.

  That is, in a non-communication state in which there is no ONU that can communicate with the OSU, power is supplied only to a part that acquires the state of each ONU, for example, a part that detects an upstream optical signal from each ONU, and supplies power to other circuits. To stop. With such a configuration, it is possible to appropriately control power supply in accordance with the presence or absence of an ONU that can communicate with itself.

  In addition, the station-side device automatically stops power supply, and when there is no ONU to communicate, for example, work is performed such as removing the board on which the PON transceiver 35 is mounted from the station-side device 201. In addition, the power consumption of the station side device 201 can be reduced.

  In the station apparatus according to the embodiment of the present invention, the power switching unit 53 receives power, that is, the power supply voltage VCC, and switches whether to supply power to the PON transmitting / receiving unit 35. When the status information acquired by the PON control unit 36 indicates that there is no communication, the power control unit 51 controls the power switching unit 53 to stop the power supply to the PON transmission / reception unit 35. To do.

  Thus, the power consumption of the station-side apparatus 201 can be efficiently reduced with a simple configuration by stopping the power supply to the PON transmitting / receiving unit 35 that consumes a large amount of power.

  Moreover, in the station side apparatus which concerns on embodiment of this invention, OSU12 contains the optical input detection part 52 for detecting the optical signal from each ONU as a status information acquisition part.

  As described above, the ONU has a configuration in which the optical input detection unit 52 for detecting the upstream optical signal from the ONU and detecting the transition to the communicable state is provided separately from the PON transmission / reception unit 35 and the PON control unit 36. It is not necessary to send a control frame such as a discovery message from the OSU to the ONU and wait for a discovery response from the ONU to be processed in order to detect whether or not it has been started. The power supply to the control unit 36 can be stopped. For this reason, the power consumption in OSU can further be reduced.

  In this case, for example, the power control unit 51 receives a logic low level signal from the PON control unit 36 indicating a non-communication state and holds this signal. With such a configuration, it is possible to perform control for stopping power supply to the PON control unit 36 in addition to the PON transmission / reception unit 35 in a no-communication state. In this case, when the optical input detection unit 52 detects the activation notification from the ONU, the power switching unit 53 may resume the power supply of the PON transmission / reception unit 35 and the PON control unit 36.

  Here, unlike the normal upstream frame transmitted from each ONU, the activation notification generated by the ONU is transmitted without communication between the OSU and each ONU. Sent from ONU to OSU. For this reason, the activation notification may be simultaneously transmitted from a plurality of ONUs to the OSU.

  On the other hand, in the station side apparatus according to the embodiment of the present invention, the optical input detection unit 52 receives the state information indicating the non-communication state by the PON control unit 36, and then the PON common to each ONU. The level of the upstream optical signal received from the line is detected, and when the detected level is equal to or higher than a predetermined threshold, it is determined that the state has changed from a no-communication state to a communicable state where an ONU that can communicate with its own OSU exists. To do. If the power control unit 51 determines that the optical input detection unit 52 has transitioned to a communicable state, the power control unit 51 resumes power supply to each circuit in the OSU other than the optical input detection unit 52, for example, the PON transmission / reception unit 35. Control to do.

  As described above, the configuration for detecting the level of the upstream optical signal received from the common PON line between the ONUs allows the OSU to easily start the ONU even when the activation notification is simultaneously transmitted from the plurality of ONUs to the OSU. Can be reliably detected.

  Moreover, in the home side apparatus which concerns on embodiment of this invention, the control part 29 receives communication information, for example, a discovery message from OSU. When the discovery message is not received for a predetermined time from a predetermined timing, the control unit 29 transmits an activation notification to the OSU. When the power control unit 51 in the OSU receives the activation notification from the control unit 29 in a state where the power supply is stopped, the power control unit 51 resumes the power supply to each circuit in the OSU.

  In this way, the ONU is activated for the OSU that has transitioned to the power saving mode and has no longer sent a discovery message for confirming the existence of a communicable ONU, by sending the activation notification autonomously from the ONU. It is possible to detect that it has occurred.

  In the PON system according to the embodiment of the present invention, the PON control unit 36 in the OSU periodically transmits communication information such as a discovery message to each ONU. The control unit 29 in the ONU receives communication information from the OSU. When the communication information cannot be received for a predetermined time from a predetermined timing, the control unit 29 transmits an activation notification to the OSU. When the power control unit 51 in the OSU receives an activation notification from the control unit 29 in a state where the power supply is stopped because it is in a non-communication state, the power control unit 51 resumes power supply to each circuit in the OSU.

  With such a configuration, it is possible to appropriately control the power supply in the station side device according to the presence or absence of an ONU that can communicate with itself. In addition, the station-side device automatically stops power supply, and when there is no ONU to communicate, for example, work is performed such as removing the board on which the PON transceiver 35 is mounted from the station-side device 201. In addition, the power consumption of the station side device 201 can be reduced.

  In addition, the configuration in which the ONU autonomously transmits a startup notification indicates that the ONU has started for an OSU that has transitioned to the power saving mode and no longer transmits communication information for confirming the presence of a communicable ONU. Can be detected.

  In the station side apparatus according to the embodiment of the present invention, the power control unit 51 is configured to perform control to stop the power supply to the PON transmission / reception unit 35 in the no-communication state. Not what you want. The power control unit 51 may be configured to perform control to stop power supply to circuits other than the optical input detection unit 52 such as the reception processing unit 33 and the transmission processing unit 34 in the no-communication state.

  Further, in the PON system according to the embodiment of the present invention, the case where a plurality of ONUs are connected to the PON line corresponding to the OSU has been described as an example, but one ONU is connected to the PON line corresponding to the OSU. Even in such a case, it is possible to achieve the object of the present invention to reduce power consumption by appropriately controlling the power supply in the station side device.

  Moreover, in the station side apparatus which concerns on embodiment of this invention, although it was set as the structure which provides the optical input detection part 52 in OSU, it is not limited to this. The PON transmission / reception unit 35 and the PON control unit 36 also serve as the optical input detection unit 52, and the PON other than the part that receives the upstream optical signal from the ONU in the non-communication state. The power supply to each circuit in the transmission / reception unit 35 may be stopped.

  In addition, the activation notification generated by the ONU may include some information, or may simply be an optical signal having a level equal to or higher than a predetermined value without information.

  The above embodiment should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

11 Overall Control Unit 12, 12-1 to 12-N Optical Line Unit (OSU)
21 PON port 22 optical reception processing unit 23 buffer memory 24 transmission processing unit 25 UNI port 26 reception processing unit 27 buffer memory 28 optical transmission processing unit 29 control unit (communication information reception unit, activation notification transmission unit)
31 Uplink IF unit 32 Control IF unit 33 Reception processing unit 34 Transmission processing unit 35 PON transceiver unit (optical transceiver unit)
36 PON control unit (status information acquisition unit, communication information transmission unit)
37,38 FIFO
51 Power control unit 52 Optical input detection unit (status information acquisition unit)
53 Power switching unit 201 Station side device (OLT)
202 Home unit (ONU)
203-1 to 203-N PON line 204-1 to 204-N optical coupler 301 PON system

Claims (7)

A station-side device for transmitting and receiving optical signals with one or more home-side devices,
An optical transceiver for transmitting and receiving optical signals to and from the home device;
A status information acquisition unit for acquiring status information indicating the status of the home side device;
When the status information acquired by the status information acquisition unit indicates a non-communication state in which the home device that can communicate with the station device does not exist, the stations other than the status information acquisition unit And a power control unit for performing control to stop power supply to the target circuit in the side device. The station side device further includes:
A power switching unit for receiving power and switching whether to supply the power to the optical transceiver;
When the state information acquired by the state information acquisition unit indicates the no-communication state, the power control unit controls the power switching unit to supply power to the optical transmission / reception unit. The station side apparatus of Claim 1 which stops. The state information acquisition unit includes an optical input detection unit for detecting an optical signal from the home device,
In the case where the state information acquired by the state information acquisition unit indicates the no-communication state, the power control unit further includes one or more in the state information acquisition unit other than the light input detection unit. The station apparatus according to claim 1, wherein control for stopping power supply to the circuit is performed. The optical transmission / reception unit transmits and receives an optical signal via an optical line common to the home device,
The status information acquisition unit detects the level of the optical signal received from the optical line after acquiring the status information indicating the no-communication state, and when the detected level is equal to or higher than a predetermined threshold, It is determined that a transition has been made from a no-communication state to a communicable state where the home-side device that can communicate with the station-side device exists,
4. The power control unit according to claim 1, wherein the power control unit performs control to resume power supply to the target circuit when the state information acquisition unit determines that the communication state has been changed. 5. The station side apparatus as described in. The home device in a communication system comprising one or more home devices and a station device for transmitting and receiving optical signals to and from each home device,
The station side device
A communication information transmission unit for periodically transmitting communication information to the home device;
A status information acquisition unit for acquiring status information indicating the status of the home side device;
When the status information acquired by the status information acquisition unit indicates a non-communication state in which the home device that can communicate with the station device does not exist, the stations other than the status information acquisition unit A power control unit for performing control to stop power supply to the target circuit in the side device,
The home device is
A communication information receiving unit for receiving the communication information from the station side device;
An activation notification transmitter for transmitting an activation notification to the station side device when the communication information is not received in the communication information reception unit for a predetermined time from a predetermined timing;
In the state where the power supply is stopped, the power control unit resumes power supply to the target circuit in the station side device when receiving the start notification from the start notification transmitting unit. . One or a plurality of home-side devices, and station-side devices for transmitting and receiving optical signals to and from each home-side device,
The station side device
A status information acquisition unit for acquiring status information indicating the status of the home side device;
When the status information acquired by the status information acquisition unit indicates a non-communication state in which the home device that can communicate with the station device does not exist, the stations other than the status information acquisition unit And a power control unit for performing control to stop power supply to the target circuit in the side device. One or a plurality of home-side devices, and station-side devices for transmitting and receiving optical signals to and from each home-side device,
The station side device
A communication information transmission unit for periodically transmitting communication information to the home device;
A status information acquisition unit for acquiring status information indicating the status of the home side device;
When the status information acquired by the status information acquisition unit indicates a non-communication state in which the home device that can communicate with the station device does not exist, the stations other than the status information acquisition unit A power control unit for performing control to stop power supply to the target circuit in the side device,
The home device is
A communication information receiving unit for receiving the communication information from the station side device;
When the communication information is not received in the communication information receiving unit for a predetermined time from a predetermined timing, including an activation notification transmitting unit for transmitting an activation notification to the station side device,
When the power control unit receives the activation notification from the activation notification transmission unit in a state where the power supply is stopped, the power control unit resumes power supply to the target circuit in the station-side device.

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