JP2013115600A - Passive optical network system, termination device and sleep state cancellation method thereof - Google Patents

Abstract

In a sleep state of an ONU, communication with an OLT is also stopped, so that a downstream frame cannot be received. In particular, since downstream frames such as incoming calls occur at unpredictable timing, it is necessary for the ONU to always establish communication with the OLT and prepare for the arrival of downstream frames. An object of the present invention is to realize a PON system that can receive a downstream frame even in a sleep state.
An activation signal monitoring circuit that reacts only to a specific activation signal that has a one-to-one correspondence with LLID is used. (1) A means for transmitting an activation signal frequency-modulated with the same optical wavelength as that of data communication and canceling the sleep state of an arbitrary ONU. (2) Means for transmitting an activation signal frequency-modulated with an optical wavelength different from that for data communication and canceling the sleep state of any ONU. (3) A means for transmitting a start signal digitally encoded at an optical wavelength different from that of data communication and canceling the sleep state of an arbitrary ONU. Any one of the means (1) to (3) is applied, and the activation signal instructing the return from the sleep state with low power consumption is monitored.
[Selection] Figure 4

Description

  The present invention relates to a passive optical network system having a power saving function, and a passive optical network system having a function of restoring a home optical transmission line termination device from a power saving state.

  As communication networks are becoming faster and wider, optical networks are being introduced to deal with them. A passive optical network system (Passive Optical Network: hereinafter referred to as PON) has a plurality of optical fiber terminal devices (Optical Line Terminal: hereinafter referred to as OLT) that are connected to a plurality of optical fibers and optical splitters that branch the optical fiber. It forms a star-type point-to-multipoint network with a home optical transmission line termination device (Optical Network Unit: hereinafter referred to as ONU). As typical PON standards, EPON (Ethernet (registered trademark) PON) standardized by IEEE 802.3, ITU-T G. There is GPON (Gigabit Capable PON) standardized in 984. The upstream frame transmitted from the ONU to the OLT in the PON and the downstream frame transmitted from the OLT to the ONU are multiplexed by wavelength division multiplexing (hereinafter referred to as WDM).

  In the downstream frame, the same data is transmitted from the OLT to all ONUs connected by optical fibers. Each ONU uses an identifier called LLID (Logical Link ID) to determine whether the received frame is addressed to itself. When a registration request is made from the ONU to the OLT, the OLT assigns a unique LLID to each ONU. When the ONU receives the downstream frame, the ONU compares the LLID assigned to the ONU with the LLID embedded in the preamble portion of the downstream frame to determine whether the frame is addressed to itself. Frames not addressed to you are discarded here.

  On the other hand, the upstream frame is multiplexed and communicated by time division multiplexing (hereinafter referred to as TDMA) in which the ONU outputs data at a specified time in accordance with transmission permission from the OLT. The LLID is also embedded in the preamble portion of the upstream frame, so that the OLT determines from which ONU the frame has arrived. The communication speed of the PON starts with a system that handles a low-speed signal such as 64 kbit / s, and a BPON (Broadband PON) that transmits and receives a fixed-length ATM cell at a maximum of about 600 Mbit / or a variable-length packet of the Ethernet at a maximum of about 1 Gbit / The introduction of EPON that transmits and receives in seconds and GPON that handles higher-speed signals of about 2.4 Gbit / sec are being promoted, and in the future, high-speed PON that can handle signals of 10 Gbit / sec to 40 Gbit / sec. Realization is required.

As the PON communication speed is improved, the power consumption of the relay device on the transmission line is also increasing. Many ONUs are installed on the network because they are installed at the subscriber's home. On the other hand, the ONU requires less bandwidth than the OLT or the upper switch group. Therefore, the ONU is left while using wasted power even during non-communication.
Patent Document 1 discloses a PON system in which an OLT requests a shift to a power saving mode for an ONU in which data carried in a downlink signal or an uplink signal is not detected for a predetermined time or more. In this way, discussions about a system that performs power saving (sleep) control of an ONU by control from the OLT, its protocol, and an opportunity for sleep are increasing.

WO2010 / 106917

  In order to save the power consumption of the ONU, it is required to put the ONU in a sleep state during non-communication. However, in the existing method, even when the non-communication state continues for a long time, the sleep state is canceled at regular intervals in order to check whether there is a downstream frame that arrives at an arbitrary timing. In actual use at the user's home, a long non-communication state is expected at bedtime or when absent, so the sleep state is canceled at regular intervals, and the presence of downstream frames in the PON LSI unit with high power consumption Confirming this diminishes the power saving effect.

  Therefore, the user wants to continue the sleep state as much as possible. However, since the communication with the OLT is stopped during the sleep state, the ONU cannot detect the presence or absence of the downstream frame. In particular, a downstream frame such as an incoming call is generated at an unpredictable timing, and it is necessary to perform a process such as ringing an incoming call promptly after detecting the frame. For this reason, the ONU needs to cancel the sleep state intermittently at short intervals and confirm the presence of a downstream frame even if the ONU is changed to the sleep state in order to realize power saving without sacrificing the convenience of the user. was there. Since the communication function with the OLT is included in the PON LSI unit and the electrical / optical conversion unit that consume large power, it is difficult to significantly reduce the power consumption even in intermittent operation.

  The present invention is a PON system in which the presence or absence of a downstream frame is always checked by a low power consumption activation signal monitoring unit instead of a high power consumption PON LSI unit in the sleep state, and the return from the sleep state can be made when the downstream frame arrives. The purpose is realization.

  In order to solve the above-described problem, the in-house terminal device of the present invention extracts from the signal received from the station-side terminal device an activation signal that activates at least one of the plurality of in-home terminal devices from the sleep state. Then, the in-home terminal device has a start signal monitoring unit for determining whether the start signal is a start signal for starting the own device from the sleep state, and the start signal monitoring unit sends the start signal to the own device. And an activation processing unit that outputs a signal for activating the own device from the sleep state to the own device.

  The activation signal monitoring unit uses a signal that does not require a large amount of power for reception, such as a signal that is different from the data signal, for example, the frequency of the activation signal is lower than the frequency of the data signal.

  Even when the ONU is in a sleep state, it is possible to realize a PON system capable of monitoring a downstream frame reception request while suppressing power consumption.

It is a block diagram which shows the example of the optical access network using PON. It is an example of the OLT block diagram in the 1st means. It is a block diagram which shows the example of the OLT side shared electrical / optical conversion part used with a 1st means. It is an example of the ONU block diagram in the 1st means. It is a block diagram which shows the example of the ONU side shared electrical / optical conversion part used with a 1st means. It is an example of the sequence diagram of a Discovery process. It is an example of the LLID-activation signal definition table in a 1st means and a 2nd means. It is an example of the sleep state management table in a 1st means and a 2nd means. It is an example of the relationship between the starting signal in a 1st means, and a downstream frame. It is an example of the waveform of a starting signal, and the pass characteristic of a pass-band variable narrow-band filter. It is an example of the operation | movement flowchart of OLT by a 1st means. It is an example of the operation | movement flowchart of ONU in a 1st means. It is an example of a sequence diagram of OLT and ONU in the first means. It is an example of the OLT block diagram in a 2nd means. It is an example of the ONU block diagram in a 2nd means. It is an example of the OLT block diagram in a 3rd means. It is an example of the ONU block diagram in a 3rd means. It is an example of an LLID-digital activation signal definition table in the third means. It is an example of the digital starting signal in a 3rd means. It is an example of the operation | movement flowchart of OLT in a 3rd means. It is an example of the operation | movement flowchart of ONU in a 3rd means.

FIG. 1 shows an example of the configuration of an optical access network to which the present embodiment is applied.
The access network 1 is connected to a public communication network (in this example, PSTN / Internet 20), which is a higher-level communication network, via the PON 10, for example, and transmits and receives data. The PON 10 includes a plurality of ONUs 110 that accommodate the OLT 100, an optical splitter 120, a trunk optical fiber 130, a branch optical fiber 140, and subscriber terminals (telephone (TEL) 180, PC 190, etc.). The PON 10 having the trunk optical fiber 130, the optical splitter 120, and the plurality of branch optical fibers 140 is connected to the OLT 100 and each ONU 110, and communication between the PSTN / Internet 20 as a higher-level communication network and the subscriber terminal, or a subscriber Communication between terminals.

  A plurality of ONUs 110 can be connected to the OLT 100 via a single trunk optical fiber 130, an optical splitter 120, and a plurality of branch optical fibers 140. In FIG. 1, as an example, five ONUs 110 are connected to the OLT 100. The downstream optical signal 150 from the OLT 100 to each ONU 110 is transmitted to all the ONUs 110 and is selected by the ONU 110 side. The upstream optical signal 170 from each ONU 110 to the OLT 100 is multiplexed and transmitted 160 by time division multiplexing that outputs data at a specified time in accordance with transmission permission from the OLT. The means for canceling the sleep state of a specific ONU 110 will be described below with reference to the drawings.

  In this embodiment, the ONU monitors the activation signal transmitted at the same optical wavelength as the data communication with low power consumption, and reacts to the activation signal addressed to the ONU to release the sleep state (hereinafter referred to as the first means) Will be described.

FIG. 2 shows an example of the configuration of the OLT 100. The OLT 100 controls data communication while the ONU 110 is in operation, the electrical transmission / reception unit 200 that communicates with the relay device on the host network side using electrical signals, the shared electrical / optical conversion unit 220 that communicates with the ONU 110 using optical signals, and the ONU 110. A medium access control unit 210; a control unit 260 that controls functional blocks in the OLT 100; a storage unit 270 that stores various settings and states; an LLID-activation signal definition table 272 that defines combinations of LLIDs and activation signals; and a specific ONU 110 Activation signal generation unit 250 that generates an activation signal for returning the sleep signal from the sleep state, an activation signal transmission unit 240 that transfers the activation signal to the shared electrical / optical conversion unit 220, and a buffer that accumulates the downstream frame until the ONU 110 returns from the sleep state 230, address to determine destination of transmission destination ONU 110 A judging unit 261, a sleep state management table 271 that holds the sleep state of all the ONU 110 which is under the destination determines the sleep state management unit 262 to the sleep state of the ONU 110, OLT 100.
The destination determination unit 261 and the sleep state management unit 262 are included in the control unit 260. The sleep state management table 271 and the LLID-activation signal definition table 272 are included in the storage unit 270.

  The activation signal in the present embodiment is a sine wave having a specific center frequency previously linked to LLID, and is selected using a passband variable narrowband filter unit (described later) in each ONU that has received the activation signal. Thus, only an arbitrary ONU can be activated.

When the upstream frame from the ONU 110 is received by the shared electrical / optical conversion unit 220, the medium access control unit 210 associates the source MAC address of the upstream frame with the source ONU information given to the preamble unit as route information. And the upstream frame is transmitted from the electrical transmission / reception unit 200.
When the downstream frame is received by the electrical transmission / reception unit 200, the medium access control unit 210 refers to the transmission destination MAC address of the downstream frame, and sends the destination ONU identification information from the route information held in advance to the preamble unit of the downstream frame. It is given and transmitted from the shared electrical / optical converter 220. It is assumed that the medium access control unit 210 has a switching function as described above.

  When the downlink frame is received, the destination determination unit 261 determines the destination of the downlink frame that has reached the medium access control unit 210 and passes it to the sleep state management unit 262. The sleep state management unit 262 associates the sleep state of each ONU 110 under the OLT 100 with the LLID assigned to each ONU 110 and the current state of each ONU 110, and manages them in the sleep state management table 271. The state of the table is updated so that the current state of the LLID assigned to the ONU 110 when the ONU 110 transitions to the sleep state indicates the “sleep” state. In addition, when the ONU 110 is registered with the OLT 100, when the registration is canceled, when the ONU is instructed to return from the sleep state by a method described later, and when the return from the sleep state is completed, the table state is updated. Is done.

  When the destination of the downstream frame is passed from the destination determination unit 261, the sleep state management unit 262 determines the sleep state of the destination ONU with reference to the sleep state management table 271, and in the “sleep” state, the activation signal generation unit 250 An activation signal corresponding to the LLID of the destination ONU 110 is generated. At this time, the activation signal is generated with reference to the LLID-activation signal definition table 272. The combination of the LLID 701 and the activation signal 702 illustrated in FIG. 7 may be previously written in the LLID-activation signal definition table 272 of the OLT at the time of shipment. The generated activation signal is transmitted from the shared electrical / optical conversion unit 220 via the activation signal transmission unit 240.

  FIG. 3 shows an example of the shared electrical / optical converter 220 included in the OLT 100. Among the shared electrical / optical conversion unit 220, the digital data transmission unit 320, the activation signal transmission unit 240, and the TOSA (Transmitter Optical Sub Assembly) 340 process the downlink signal, and the digital signal reception processes the upstream signal. Part 310 and ROSA (Receiver Optical Sub Assembly) 330.

In this embodiment, the digital data transmission unit 320 and the activation signal transmission unit 240 are connected to the same TOSA 340 in order to transmit the activation signal at the same optical wavelength as the data communication. Both the main signal from the digital data transmission unit 320 and the activation signal from the activation signal transmission unit 240 that outputs the activation signal to wake up the sleeping ONU 110 are input to the TOSA 340. These electrical signals are converted into optical signals by the TOSA 340, and these optical signals are multiplexed as downstream frames by the WDM 350.
In the downstream frame, the bias current driving unit 322 and the modulation current driving unit 321 of the digital data transmission unit 320 drive an LD (LASER Diode) (not shown) in the TOSA 340, and the activation signal transmission unit 240 also transmits the activation signal. LDs in the same TOSA 340 are driven to be converted into optical signals.

  On the other hand, an optical signal that is an upstream frame from the ONU 110 is separated by the WDM 350 and input to the ROSA 330, converted into an electrical signal by the ROSA 330, and then input to the digital data receiving unit 310. Thus, the light received by the ROSA 330 and the light transmitted by the TOSA 340 are multiplexed / demultiplexed by the WDM 350.

FIG. 4 shows an example of the configuration of the ONU 110 to which the present embodiment is applied. The ONU 110 includes a shared electrical / optical conversion unit 400 that communicates with the OLT 100 using optical signals, a PON LSI unit 410 that functions as a data processing unit such as performing protocol conversion between the OLT 100 and a subscriber terminal, and data during operation of the ONU 110 A medium access control unit 411 for controlling communication, a buffer unit 430 for storing traffic data, an electrical transmission / reception unit 420 for communicating with subscriber terminals and the like by electrical signals, and a control unit 450 for controlling functional blocks in the ONU 110 , A storage unit 440 for storing various settings and states, an activation signal monitoring unit 460 for monitoring an activation signal and passing the activation signal for the ONU to the activation processing unit 452, an LLID-activation signal definition for defining a combination of an LLID and an activation signal Passband based on table 441, LLID-activation signal definition table 441 A filter constant configuration unit 451 for setting a filter constant of a variable narrowband filter unit 461 (described later), a passband variable narrowband filter unit 461 for selecting an activation signal to the ONU 110, and an activation processing unit 452 for the selected activation signal Is provided with a smoothing / amplifying unit 462 that converts the signal so that it can be easily handled, and a startup processing unit 452 that receives the startup signal and releases the sleep state of the ONU 110.
The filter constant configuration unit 451 and the activation processing unit 452 are included in the control unit 450. The passband variable narrowband filter unit 461 and the smoothing / amplifying unit 462 are included in the activation signal monitoring unit 460. The LLID-activation signal definition table 441 is included in the storage unit 440. The medium access control unit 411 is included in the PON LSI unit 410.

The ONU 110 sets the filter constant of the passband variable narrowband filter unit 461 at the time when the LLID is assigned so that it reacts only to the activation signal having the center frequency associated with its own LLID. Since the values of the LLID-activation signal definition table 441 of the ONU 110 and the LLID-activation signal definition table 272 of the OLT 100 are the same, the ONU 110 should receive the center frequency of the activation signal to be sent using the LLID as a key. You can know the center frequency of the start signal. The combination of the LLID 701 and the activation signal 702 may be written in the LLID-activation signal definition table at the time of shipment.
FIG. 7 shows an example of the LLID-activation signal definition table 441. This table stores the LLID 701 of each ONU 110 and the center frequency 702 of the activation signal corresponding thereto. The filter constant configuration unit 451 refers to the LLID-activation signal definition table 441 and sets the filter constant of the passband variable narrowband filter unit 461.

When the OLT 100 receives a downstream signal addressed to the ONU 110 after the ONU 110 transitions to the sleep state, the OLT 100 transmits an activation signal having a center frequency associated with the LLID of the ONU 110. The ONU 110 converts the transmitted activation signal into an electrical signal by the shared electrical / optical transmission unit 400 and passes it to the passband variable narrowband filter unit 461.
A configuration example of the shared electrical / optical conversion unit 400 is shown in FIG. Since the filter constant of the passband variable narrowband filter unit 461 is already set, only the activation signal having the center frequency associated with the own LLID passes. The smoothing / amplifying unit 462 smoothes a sine wave weak electric signal that has passed through the variable passband narrowband filter unit 461 with a capacitor or the like, amplifies the signal, and inputs the amplified signal to the activation processing unit 452 as a logic signal. The activation processing unit 452 instructs the PON LSI unit 410 to cancel the sleep state. If the activation signal monitoring unit 460 configures the filter constant of the passband variable narrowband filter unit 461 when assigning the LLID, then the activation signal monitoring unit 460 becomes a filter mainly composed of passive components, and the smoothing / amplifying unit 462 also has a low speed on the order of kHz. Since it is only necessary to amplify the signal, the PON LSI unit 410 can operate with much less power than a method in which the PON LSI unit 410 communicates with the OLT 100 and monitors the presence or absence of a downstream frame. On the other hand, the PON LSI unit 410 that receives a normal signal receives a signal in synchronization with a high-speed signal, and therefore consumes more power than the activation signal monitoring unit 460.

In this embodiment, the sleep state of the ONU 110 is, for example, power supply or clock supply to the digital data reception unit 560, the TOSA 520, the digital data transmission unit 550, and the PON LSI unit 410 in the shared electrical / optical conversion unit 400. At least one of them is stopped, data communication with the shared electrical / optical conversion unit 220 of the OLT 100 is interrupted, and only the function of accumulating the upstream frame received by the electrical side transmission / reception unit 420 in the buffer unit 430 is continued. This is to stop the function.
In addition, the activation signal monitoring unit 460 monitors the activation signal from the OLT 100 with low power consumption, and prepares for a series of operations for releasing the sleep state when the activation signal associated with its own LLID is received.
Also in the present embodiment and other embodiments, the sleep state is not limited to those exemplified in the embodiment, and at least a part of the functional units in the apparatus excluding the functional units necessary for receiving and processing the activation signal. The state where the function part of ceases to function.

FIG. 5 shows an example of the shared electrical / optical conversion unit 400 included in the ONU 110. In shared electric / optical converter 400, first, an optical signal is separated into upstream and downstream by WDM 500 that combines and demultiplexes the optical signal according to the wavelength. In this embodiment, since the activation signal is transmitted at the same optical wavelength as that of the data communication, the downstream optical signal is converted into an electrical signal by the ROSA 510, and then only the data signal in the GHz order passes and the activation signal in the kHz order is attenuated. The HPF 540, on the other hand, passes only the start signal in the kHz order and passes it to the LPF 530 which attenuates the data signal in the GHz order. The activation signal that has passed through the LPF 530 is passed to the passband variable narrowband filter unit 461. The data signal that has passed through the HPF 540 is converted into digital data by the digital data receiving unit 560 and passed to the medium access control unit 411.
The upstream frame is passed from the medium access control unit 411 to the digital data transmission unit 550, and the bias current driving unit 552 and the modulation current driving unit 551 of the digital data transmission unit 550 drive an LD (not shown) in the TOSA 520 to light. The signal is input to the WDM 500. Note that the LPF 530 may be omitted as long as the signal strength for data communication can be sufficiently attenuated only by the passband variable narrowband filter unit 461.

FIG. 6 shows an example of a sequence diagram of the Discovery process. This sequence diagram shows a procedure at the time of the Discovery process for registering the ONU 110 under the OLT 100.
The OLT 100 periodically sends a Discovery_Gate frame (600) to give the unregistered ONU 100 an opportunity to request registration. The ONU 110 wishing to register transmits a REGISTER_REQ frame in time for the response permission time Discovery Window 601 set by the OLT 100 (602). When the OLT 100 permits registration, an LLID is assigned to the ONU 110 and the LLID is notified to the ONU 110 (603). Since the LLID is a unique ID assigned to the ONU, in this embodiment, the activation target is specified using this value. When the LLID is assigned, the ONU 110 refers to the LLID-activation signal definition table 441 and acquires the center frequency of the activation signal for the own LLID (604). The filter constant configuration unit 451 of the ONU 110 sets 605 the filter constant of the passband variable narrowband filter unit 461 so as to pass the activation signal having this center frequency. Thereafter, the Discovery process is executed as usual.

  FIG. 8 is a sleep state management table in which the LLID 801 and the current state 802 (described later) of the ONU to which the LLID is assigned are stored.

  FIG. 9 shows an example of the activation signal. In this example, the relationship between the downstream frame transmitted at 1.25 Gbps and the activation signal is indicated by the strength of the electric signal that drives the LD. Considering the CN ratio (Carrier / Noise ratio) to be equal, the clock of the downstream signal is in the order of GHz, whereas the center frequency of the sine wave of the activation signal is in the order of kHz and the frequency is 10 6 lower. The signal intensity may be as small as 10 6. However, in order to increase the technical difficulty unnecessarily for extremely weak electric signals, in this example, the average power 901 of the activation signal is set to about 1/10 of the average power 900 of the downstream frame. The optical data transmitted in the PON section is transmitted by modulating the modulation current that drives the LD. The LD has a characteristic that when the driving current is increased, the light emission is only weakly up to the light emission threshold value, and the light intensity rapidly increases when the light emission threshold value is exceeded. Therefore, in order to cause the LD to react linearly to the change in the modulation current, a bias 902 up to the light emission threshold is applied to the LD drive current. An activation signal 904 is transmitted in a form superimposed on this bias, and a downstream frame 903 is transmitted in a form superimposed on the activation signal 904. Since the activation signal 904 and the downstream frame 903 are separated by the HPF 540 and the LPF 530 on the ONU 110 side, the activation signal 904 can be transmitted at an arbitrary timing regardless of the transmission state of the downstream frame 903.

  FIG. 10 shows an example of the waveform of the activation signal and the pass characteristics of the passband variable narrowband filter unit 461. As the activation signal, a sine wave having a center frequency fc defined by the LLID-activation signal definition tables 272 and 441 in FIG. 7 is used. The passband variable narrowband filter unit 461 can change the center frequency of the sine wave to be passed by changing the filter constant. In FIG. 10, for example, by setting a filter constant to pass an activation signal having a center frequency of fc2, fc1, fc3, fc4, fc5 and other sine waves having a center frequency are passed through a variable passband narrowband filter unit 461. And only fc2 passes.

  FIG. 11 shows an example of an operation flow diagram of the OLT when the specific ONU in the sleep state is returned from the sleep state by the first means.

  The OLT 100 periodically executes the Discovery process (1101). When the ONU 110 is connected under the OLT 100, the OLT 100 receives a registration request from the ONU 110 during the Discovery process (1102). In the Discovery process 1101, the OLT 100 assigns a unique LLID to the ONU 110 (1103). Since this embodiment is characterized in that the sleep state of only an arbitrary ONU 110 among a maximum of 128 ONUs connected to the OLT 100 can be canceled, it is convenient to use this LLID for the purpose of specifying the activation target.

  After completion of PON LINK establishment / authentication with the ONU 110 (1104), the sleep state management unit 262 updates the value 802 corresponding to the LLID of the specific ONU 110 in the sleep state management table 271 shown in FIG. (1105). The sleep state management table 271 indicates the LLID 801 and the current state 802 of the ONU having the LLID. The sleep state management unit 262 refers to the sleep state management table 271 and determines whether the ONU 110 is in the sleep state.

When the current state 802 of the ONU 110 is in the “activated” state, the OLT 100 instructs the transition to the sleep state according to the usage status of the ONU 110 (1106). Here, the ONU 110 may determine the usage status of each ONU 110 based on, for example, the amount of upstream signal requested by the ONU 110 to transmit or the amount of downstream signal addressed to the ONU 110, and appropriately instruct the ONU 110 to transition to the sleep state. it can. Alternatively, in response to a request from the ONU 110 to shift to the sleep state, the ONU 110 may be instructed to shift to the sleep state.
The sleep state management unit 262 confirms that the ONU 100 has transitioned to the sleep state, and updates the value 802 corresponding to the LLID in the sleep state management table 271 to the “sleep” state (1107).

  After the ONU 110 transitions to the sleep state, when the OLT 100 receives a downstream frame addressed to the ONU, a return process from the sleep state is started. When the OLT 100 receives a downlink frame (1108), the destination determination unit 261 determines to which LLID the data is to be transmitted (1109). The sleep state management unit 262 refers to the sleep state management table 271 using this LLID as a key, and determines the current state of the destination ONU (1110).

  If the current state is the “activated” state, the OLT 100 transmits a downlink frame as usual 1111. If the current state is the “sleep” state, the ONU 110 is not in a state in which it can receive a downstream frame, and therefore the OLT 100 stores the downstream frame for the LLID in the buffer unit 230 until the return from the sleep state is completed (1112). ). Next, the activation signal generation unit 250 refers to the LLID-activation signal definition table 272, acquires the center frequency 702 of the activation signal associated with the destination ONU (1113), and generates an activation signal for the LLID ( 1114) Transmit (1115).

At this time, the sleep state management unit 262 updates the value 802 corresponding to the LLID in the sleep state management table 271 to the “active” state (1116). The sleep state management unit 262 determines that the ONU 110 has returned from the sleep state upon completion of the PON LINK establishment / authentication of the OLT 100 and the ONU 110 (1117), and “starts” the value 802 corresponding to the LLID in the sleep state management table 271. The state is updated (1118). Since the ONU 110 can receive the downlink frame from here, the OLT 100 starts transmission of the downlink frame stored in the buffer unit 230 (1119).
Note that the current state of the destination ONU is determined (1110). If the current state is the “active” state, the process proceeds to PON LINK establishment / authentication completion (1117).

  FIG. 12 shows an example of an operational flowchart of the ONU that returns from the sleep state by the first means. When the ONU 110 detects the Discovery process (1201), it makes a registration request to the OLT 100 (1202). When the LLID is assigned from the OLT 100 in the Discovery process (1203), the filter constant configuration unit 451 refers to the LLID-activation signal definition table 441 and acquires the center frequency of the activation signal associated with the own LLID (1204). ). Next, the filter constant configuration unit 451 sets the filter constant of the passband variable narrowband filter unit 461 so that only the activation signal having this center frequency passes (1205). Thereafter, the ONU 110 transitions to the sleep state in response to the transition instruction to the sleep state for the ONU 110 issued from the OLT 100 based on the usage status of the ONU 110 (1206).

After the ONU 110 transitions to the sleep state, when the OLT 100 receives a downstream frame addressed to the ONU, the OLT 100 transmits an activation signal to the ONU 110. The activation signal transmitted from the OLT 100 is received by all ONUs 110 under the OLT 100 (1207).
. Since the passband variable narrowband filter unit 461 of each ONU 110 is set to pass only the activation signal having the center frequency associated with the own LLID, the activation processing unit 452 responds only to the activation signal addressed to the own LLID. (1208). If it is determined that the activation signal is “for own LLID”, the activation processing unit 452 sends a signal to the PON LSI unit 410, and the ONU 110 starts activation (1210). At this time, other ONUs 110 having different LLIDs are discarded because the activation signal cannot pass through the passband variable narrowband filter unit 461 (1209). The completion of activation is confirmed by PON LINK establishment / authentication completion 1211. The ONU 110 receives the downstream frame from the OLT 100 when the activation is completed (1212).

  FIG. 13 shows an example of a sequence diagram between the OLT 100 and the ONU 110. The ONU 110 shifts to a sleep state according to an instruction issued from the OLT 100 based on the usage status of the ONU 110 (1301). When receiving the downstream frame (1302), the OLT 100 determines the current state of the destination ONU 110. When the current state is the sleep state (1303), the return processing from the sleep state is started. The OLT 100 accumulates the downlink frames in the buffer unit 230 until the ONU 110 can receive the downlink frames (1304). At the same time, the OLT 100 refers to the LLID-activation signal definition table 272 and generates an activation signal (1305).

  Then, the OLT 100 transmits an activation signal to the ONU 110 (1306). Each ONU 110 determines whether it is an activation signal to respond (1307). In the case of the activation signal for the own LLID, the ONU 110 starts activation (1308). When the activation starts, an authentication process is executed between the OLT 100 and the ONU 110 (1309). The completion of activation is confirmed upon completion of establishment and authentication of the PON LINK (1310), and after completion of activation of the ONU 110, the OLT 100 sequentially transmits the downstream frames stored in the buffer unit 230 (1311). Thereafter, according to the use state of each ONU 110, the OLT 100 instructs the transition to the sleep state, and each ONU 110 transitions to the sleep state (1312).

By using the above means, the present embodiment consumes less power than the existing method in which the PON LSI unit 410 is intermittently operated even in the sleep state for the downstream frame that arrives at an arbitrary timing, and the presence or absence of the downstream frame is confirmed. Since the PON LSI unit 410 with high power can be kept stopped and the start signal monitoring unit 460 with low power consumption can be monitored, the contribution to power saving is high. Further, the OLT 100 instructs the transition to the sleep state in accordance with the use state of the ONU 110, and the sleep state of the ONU 110 continues until the OLT 100 receives a downstream frame addressed to the ONU. Therefore, when the user goes out or goes to bed, it can be expected to maintain the sleep state for several hours. Since the present embodiment uses the same optical wavelength as that of data communication and does not require a dedicated optical component, the cost advantage at the time of manufacture is high.
This is merely an example, and the activation signal may be monitored by using a method other than the passband variable narrowband filter unit to select activation signals for other ONUs 110.

  In this embodiment, the ONU monitors the activation signal transmitted from the OLT at a different optical wavelength from the data communication with low power consumption, and reacts to the activation signal addressed to the ONU to release the sleep state (hereinafter referred to as the second signal). Will be described.

  FIG. 14 shows an example of the configuration of an OLT 1400 that implements the second means. The OLT 1400 includes a data electrical / optical converter 1401 that performs data communication with the ONU 1500 using optical signals, an activation signal electrical / optical converter 1403 that converts an activation signal into light, and a WDM 1402 that separates / multiplexes them. Other configurations are the same as those of the first means shown in FIG.

The second means is characterized in that the OLT 1400 transmits an activation signal at a wavelength different from that of the data signal. Therefore, the shared electricity / light converter 220 in the first means is divided into a data electricity / light converter 1401 and an activation signal electricity / light converter 1403.
The data electrical / optical conversion unit 1401 includes a digital data reception unit 310, a digital data transmission unit 320, a ROSA 330, a TOSA 340, and a WDM 350 as in FIG. 3, and transmits / receives data to / from the medium access unit 210.
The activation signal electrical / optical converter 1403 includes a TOSA (not shown) having a different emission wavelength from the TOSA 340 in order to handle an optical wavelength different from that of the data signal. For example, since 10G-EPON defined by IEEE 802.3av uses optical wavelengths of 1270 nm, 1577 nm, 1310 nm, and 1490 nm, other optical wavelengths are selected for the activation signal. In consideration of long-distance transmission of several tens of kilometers, it is desirable to select an optical wavelength with little loss.

  The activation signal electrical / optical converter 1403 transmits an activation signal to the ONU 1500 as an optical signal. The optical signal handled by the data electrical / optical conversion unit 1401 and the optical signal handled by the activation signal electrical / optical conversion unit 1403 are separated / multiplexed by the WDM 1402. Whereas the WDM 350 separates / multiplexes the upstream and downstream optical signals of data, the WDM 1402 separates / multiplexes the data signal and the activation signal.

  FIG. 15 shows an example of the configuration of the ONU 1500 that implements the second means. The ONU 1500 is a data electrical / optical converter 1502 that transmits / receives data with the OLT 1400 using an optical signal, an activation signal electrical / optical converter 1503 that converts an activation signal received by light into electricity, an optical signal of the data and an activation signal A WDM 1501 for separating / multiplexing an optical signal is provided. Other configurations are substantially the same as those of the first means shown in FIG.

In the second means, since the data communication and the activation signal are transmitted at different optical wavelengths, first, the WDM 1501 separates / multiplexes the optical wavelengths for the data communication and the activation signal. Similar to the configuration of the OLT 1400 in FIG. 14, the shared electrical / optical converter 400 in the first means is divided into a data electrical / optical converter 1502 and an activation signal electrical / optical converter 1503.
The data electrical / optical conversion unit 1502 includes WDM 500, ROSA 510, TOSA 520, digital data reception unit 560, and digital data transmission unit 550, as in FIG. 5, and transmits / receives data to / from the medium access unit 411.
The activation signal electrical / optical conversion unit 1503 includes an ROSA (not shown) having a light receiving wavelength different from that of the ROSA 510, and receives an activation signal from the OLT 1400. Unlike the case of FIG. 5, the LPF 530 and the HPF 540 are not required after the ROSA 510, because the data communication and the activation signal have different optical wavelengths, and the optical wavelength for the data communication and the activation signal are separated by the WDM 1501 in the previous stage.

In the present embodiment, the sleep state of the ONU 1500 is, for example, at least one of power supply or clock supply to the data electrical / optical conversion unit 1502 and the PON LSI unit 410 and data electrical / optical conversion of the OLT 1400 Data communication with the unit 1401 is interrupted, and only the function of accumulating the uplink frame received by the electrical transmission / reception unit 420 in the buffer unit 430 is continued, and other functions are stopped.
In addition, the activation signal monitoring unit 460 provides a series of operations for monitoring the activation signal from the OLT 1400 with low power consumption and canceling the sleep state when the activation signal associated with its own LLID is received.

  The operation flow of the OLT 1400 is substantially the same as that of FIG. 11 except for step 1115 of FIG. In step 1115 of FIG. 11, in this embodiment, the activation signal transmission unit 240 generates an activation signal of an electrical signal, and the activation signal electrical / optical conversion unit 1403 converts the signal into an optical signal and transmits the activation signal to the ONU 1500. .

  The operation flow of the ONU 1500 is substantially the same as that of FIG. 12 except for step 1207 of FIG. In step 1207 of FIG. 12, in this embodiment, the activation signal electrical / optical conversion unit 1503 converts the activation signal of the optical signal into an electrical signal and passes it to the passband variable narrowband filter unit 461.

  By using an optical wavelength different from that for data communication for the start signal, the WDM 1402 and the start signal electrical / optical converter 1403 are required on the OLT 1400 side, and the WDM 1501 and the start signal electrical / optical converter 1503 are required on the ONU 1500 side. Will increase. However, since the optical wavelength is different from that of data communication, the optical signal used for the start signal does not affect the characteristics that affect the error rate of data communication such as deterioration of extinction ratio, so the transmission quality of data communication is better maintained. it can.

  By using the above means, it is possible to monitor a downstream frame that arrives at an arbitrary timing even in a sleep state with lower power consumption than when the PON LSI unit 410 monitors. This is one embodiment, and a method other than the passband variable narrowband filter unit 461 may be used for selecting the activation signal.

  In this embodiment, an ONU monitors a digital activation signal transmitted at a different optical wavelength from that of data communication with low power consumption, and reacts to the digital activation signal addressed to the ONU to release a sleep state (hereinafter, a third example). Will be described.

  FIG. 16 shows an example of the configuration of an OLT 1800 that implements the third means. The OLT 1800 generates a digital activation signal from a bit pattern obtained by referring to an LLID-digital activation signal definition table 1803 and an LLID-digital activation signal definition table 1803 that link the LLID and a bit pattern to be described later. Transmitter 1802, digital activation signal electrical / optical converter 1801 for converting the electrical digital activation signal received from digital activation signal generation / transmission unit 1802 into light, and data electrical / optical for data communication with the ONU 1900 using optical signals The conversion unit 1401 includes a WDM 1402 that separates / multiplexes these two optical signals. The LLID-digital activation signal definition table 1803 is included in the storage unit 270. Other configurations are the same as those of the first means shown in FIG.

The third means also transmits a digital activation signal at a wavelength different from that for data communication. Therefore, the shared electrical / optical converter 220 in the first means is divided into a data electrical / optical converter 1401 and a digital activation signal electrical / optical converter 1801.
The data electrical / optical conversion unit 1401 includes a digital data reception unit 310, a digital data transmission unit 320, a ROSA 330, a TOSA 340, and a WDM 350 as in FIG. 3, and transmits / receives data to / from the medium access unit 210.
The digital activation signal electrical / optical converter 1801 includes a TOSA 340 (not shown) having a light emission wavelength different from that of the TOSA 340 in order to handle an optical wavelength different from that of the data signal. For example, since 10G-EPON defined by IEEE 802.3av uses optical wavelengths of 1270 nm, 1577 nm, 1310 nm, and 1490 nm, other optical wavelengths are selected for the activation signal. In consideration of long-distance transmission of several tens of kilometers, it is desirable to select an optical wavelength with little loss.
The digital activation signal electrical / optical converter 1801 transmits an activation signal to the ONU 1900 with light.

  When the downstream frame destination ONU 1900 is in the sleep state, the OLT 1800 refers to the LLID-digital activation signal definition table 1803 and acquires the bit pattern of the digital activation signal associated with the LLID of the destination ONU 1900. The digital activation signal generation / transmission unit 1802 generates / transmits a digital activation signal from the obtained bit pattern, and the digital activation signal electrical / optical conversion unit 1801 converts the light into light, which is multiplexed with the data communication light by the WDM 1402. Sent to.

  Unlike FIG. 3 shown in the first means, the digital data transmission unit 320 and the digital activation signal generation / transmission unit 1802 are connected to different TOSAs and drive LDs having different optical wavelengths. The optical signal handled by the data electrical / optical converter 1401 and the optical signal handled by the digital activation signal generator / transmitter 1802 are separated / multiplexed by the WDM 1402.

  FIG. 17 shows an example of the configuration of the ONU 1900 that implements the third means. The ONU 1900 and the OLT 1800 transmit / receive data using an optical signal to / from the data electrical / optical converter 1502, the digital activation signal received by the optical signal to the electrical / optical converter 1901, and the data optical signal and activation WDM 1501 for separating / multiplexing the optical signal of the signal, LLID-digital activation signal definition table 1921 that associates the bit pattern of the LLID and the digital activation signal, the bit pattern of the received digital activation signal, and the bit pattern associated with the own LLID A small-scale microcomputer 1911 for collation is provided. The LLID-digital activation signal definition table 1921 is included in the storage unit 1920. The small-scale microcomputer 1911 is included in the activation signal monitoring unit 1910. Other configurations are the same as those of the first means shown in FIG.

In this embodiment, the sleep state of the ONU 1900 is, for example, at least one of power supply or clock supply to the data electrical / optical conversion unit 1502 and the PON LSI unit 410 to stop data electrical / optical conversion of the OLT 1800. Data communication with the unit 1401 is interrupted, and only the function of accumulating the uplink frame received by the electrical transmission / reception unit 420 in the buffer unit 430 is continued, and other functions are stopped.
The activation signal monitoring unit 1910 is prepared for a series of operations for monitoring the activation signal from the OLT 1800 with low power consumption and canceling the sleep state when the activation signal associated with its own LLID is received.

  FIG. 18 shows an LLID-digital activation signal definition table 1921 held by the storage unit 1920, in which an LLID 2201 and a corresponding bit pattern 2202 of the digital activation signal are stored. The bit pattern 2202 is associated with a different value for each LLID 2201.

  As shown in the LLID-digital activation signal definition table 1921 in FIG. 18, the LLID 2201 and the bit pattern 2202 of the digital activation signal are determined in a one-to-one relationship in advance. In the LLID-activation signal definition table of FIG. 7 used in the first means and the second means, the relationship between the LLID and the center frequency of the activation signal is defined, whereas the LLID-digital activation signal used in this embodiment. The definition table defines the relationship between the LLID 2201 and the bit pattern 2202 included in the digital activation signal. Similar to the first means, the LLID-digital activation signal definition table has the same value in both the OLT and the ONU, and the value may be written at the time of shipment. This bit pattern is an example, and the present invention is not limited to this.

In the third means, since the data communication and the digital activation signal are transmitted at different optical wavelengths, first, the WDM 1501 separates / multiplexes the optical wavelengths for the data communication and the digital activation signal. Similar to the configuration of the OLT 1800 in FIG. 16, the shared electrical / optical converter 400 in the first means is divided into a data electrical / optical converter 1502 and a digital activation signal electrical / optical converter 1901.
The data electrical / optical conversion unit 1502 includes WDM 500, ROSA 510, TOSA 520, digital data reception unit 560, and digital data transmission unit 550, as in FIG. 5, and transmits / receives data to / from the medium access unit 411.
The digital activation signal electrical / optical conversion unit 1901 includes an ROSA (not shown) having a light receiving wavelength different from that of the ROSA 510, and receives an activation signal from the OLT 1800. Unlike the case of FIG. 5, the LPF 530 and the HPF 540 are not required after the ROSA 510, because the data communication and the activation signal have different optical wavelengths, and the optical wavelength for the data communication and the activation signal are separated by the WDM 1501 in the previous stage.

  FIG. 19 shows an example of the digital activation signal. In this example, the digital activation signal is generated in a frame format including a start symbol 2301, a bit pattern 2302 associated with the LLID, and an inverted bit pattern 2303 to detect a bit error during transmission. In order to suppress the power consumption of the digital activation signal processing circuit, the digital activation signal is transmitted with a clock in the order of kHz, which is slower than data communication.

  The small-scale microcomputer 1911 starts frame synchronization upon detecting the start symbol 2301, confirms that there is no contradiction between the bit pattern 2302 associated with the LLID and the inverted bit pattern 2303, and then registers the self-registered LLID. Match the bit pattern. If the bit pattern of the activation signal matches the bit pattern for the own LLID, the small-scale microcomputer 1911 determines that the activation signal is a digital activation signal for the own LLID, and instructs the activation processing unit 452 to start the activation process. The activation processing unit 452 works on the PON LSI unit 410 and instructs to return from the sleep state. If it does not match the bit pattern for its own LLID, the received digital activation signal is discarded.

FIG. 20 shows an example of an operation flow diagram of the OLT when the third means returns a specific ONU in the sleep state from the sleep state. From the execution of the Discovery process (1101) to the start of the accumulation of downstream frames (1112), the same operation as in FIG. 11 is performed.
In the third means, since the activation signal is transmitted digitally, the step of generating and transmitting the digital activation signal is different from that of the first means. After the OLT 1800 starts storing the downlink frame for LLID of the specific ONU in the buffer unit 430 (1112), the digital activation signal generation / transmission unit 1802 refers to the LLID-digital activation signal definition table 1803 and refers to the LLID. The digital activation signal bit pattern is acquired (2001). The digital activation signal generation / transmission unit 1802 assembles the acquired bit pattern into the frame format described above, and generates a digital activation signal (2002). Since the means of this embodiment also uses a different optical wavelength from that for data communication for the digital activation signal, the digital activation signal is transmitted from the digital activation signal electrical / optical converter 1801 (2003).
Thereafter, the same operations as those in steps 1116 to 1119 in FIG. 11 are performed.

FIG. 21 shows an example of an operational flowchart of the ONU that returns from the sleep state by the third means.
The process from the discovery process detection (1201) to the LLID assignment (1203) is the same as in FIG.
The small-scale microcomputer 1911 refers to the LLID-digital activation signal definition table 1921 based on the LLID assigned from the OLT 1800, acquires the bit pattern of the digital activation signal for the own LLID (2101), and is the digital to which it should respond. The bit pattern of the start signal is set (2102). Then, the state transits to the sleep state (1206).

When the ONU 1900 receives the digital activation signal from the OLT 1800 (2103), the small-scale microcomputer 1911 collates the bit pattern included in the digital activation signal with the bit pattern previously set in the small-scale microcomputer 1911 when LLID is assigned. Then, it is determined whether the activation signal is for the own LLID (2104). If the bit patterns are different, the digital activation signal for other LLID is determined and discarded (1209). If the bit patterns match, it is determined as a digital activation signal for its own LLID, and activation is started (1210).
Thereafter, the same operation as in steps 1211 to 1212 in FIG. 12 is performed.

Considering a simple model, the power consumption of a digital circuit is proportional to the operating frequency. The power consumption of the PON LSI unit 410 that operates with a clock in the order of GHz and the small-scale microcomputer 1911 that operates with a clock in the order of kHz differ greatly. By using the third means, it is possible to use the digital activation signal monitoring unit 1910 rather than intermittently monitoring the PON LSI unit 411 with high power consumption even in the sleep state for the downstream frame that arrives at an arbitrary timing. The presence / absence of a downstream frame can be monitored with low power consumption.
For the same reason, the activation signal monitoring unit 460 of the first and second embodiments also consumes less power than the PON / LSI unit 410 that processes normal data signals.

  As described above, by providing the activation signal monitoring units 460 and 1910 that can operate with low power consumption separately from the PON LSI unit 410 that consumes large power to process high-speed and high-frequency signals, The ONU can always monitor the reception request of the downstream frame even in the sleep state. In addition, although a maximum of 128 ONUs are connected to the OLT, only one arbitrary unit can be returned from the sleep state in the method described in the embodiment.

  In the first embodiment, an activation signal is transmitted to the ONU at the same optical wavelength as that of the downstream frame. This means can be realized at low cost because the present optical parts can be used for both OLT and ONU. The activation signal is, for example, a sine wave having a specific center frequency previously linked to the LLID, and only an arbitrary ONU can be activated by selecting it with the variable passband narrowband filter unit of the ONU. The waveform is not limited to a sine wave, but may be any other waveform as long as the center frequency can be identified by a filter.

  In the second embodiment, an activation signal is transmitted to the ONU at an unused optical wavelength that is not used for data transmission / reception in the PON system. This means has the advantage of not affecting the transmission quality of the main signal. The activation signal is, for example, a sine wave having a specific center frequency previously linked to the LLID, and only an arbitrary ONU can be activated by selecting it with the variable passband narrowband filter unit of the ONU.

  In the third embodiment, an activation signal is transmitted to the ONU at an unused optical wavelength in the PON system. The third embodiment is characterized in that the activation signal is digitally encoded.

1 Access network 10 PON
20 PSTN / Internet 100 OLT
110 ONU
120 Splitter 130, 140 Optical fiber 150 Downstream signal 160, 170 Upstream signal 180, 190 Terminal 200 OLT side electrical side transceiver 210 OLT side medium access control unit 220 OLT side shared electrical / optical converter 230 OLT side buffer unit 240 Activation signal Transmission unit 250 Activation signal generation unit 260 OLT side control unit 261 Destination determination unit 262 Sleep state management unit 270 OLT side storage unit 271 Sleep state management table 272 OLT side LLID-activation signal definition table 310 OLT side digital data reception unit 320 OLT side Digital data transmitter 330 OLT side ROSA
340 OLT side TOSA
350 WDM
400 ONU side shared electric / optical transmission unit 410 ONU side PON LSI unit 411 ONU side medium access control unit 420 ONU side electric side transmission / reception unit 430 ONU side buffer unit 440 ONU side storage unit 441 ONU side LLID-activation signal definition table 450 ONU Side control unit 451 Filter constant configuration unit 452 Activation processing unit 460 Activation signal monitoring unit 461 Passband variable narrowband filter unit 462 Smoothing / amplification unit 500 WDM
510 ONU side ROSA
520 ONU side TOSA
530 LPF
540 HPF
550 ONU side digital data transmission unit 560 ONU side digital data reception unit 1400 OLT
1401 OLT side data electrical / optical converter 1402 WDM
1403 OLT side start signal electrical / optical converter 1500 ONU
1501 WDM
1502 ONU side data electrical / optical converter 1503 ONU side activation signal electrical / optical converter 1800 OLT
1801 OLT side digital activation signal electrical / optical conversion unit 1802 Digital activation signal generation / transmission unit 1803 OLT side LLID-digital activation signal definition table 1900 ONU
1901 ONU side digital activation signal electrical / optical conversion unit 1910 activation signal monitoring unit 1911 small-scale microcomputer 1920 ONU side storage unit 1921 ONU side LLID-digital activation signal definition table

Claims (10)

The in-house terminating device in a passive optical network system in which a plurality of in-house terminating devices are connected via a station-side terminating device and an optical splitter,
A wavelength demultiplexing unit that multiplexes and demultiplexes the optical signal transmitted and received with the termination device according to the wavelength;
An electrical / optical converter that converts the optical signal received from the termination device and separated by the wavelength demultiplexing unit into an electrical signal;
An activation signal monitoring unit that determines whether or not the electrical signal from the electrical / optical conversion unit is an activation signal for activating the device from a sleep state;
An activation processing unit that outputs a signal for activation from a sleep state to the device when the activation signal is determined by the activation signal monitoring unit to be a signal addressed to the device; Termination equipment. The in-home terminal device according to claim 1,
The wake-up signal is transmitted at a lower frequency than a data signal transmitted and received between the station-side ending device and the premises terminating device. The in-home terminal device according to claim 2,
A data processing unit for receiving and processing the data signal;
The in-home terminal device characterized in that the activation signal monitoring unit consumes less power than the data processing unit. The in-home terminal device according to claim 2,
The activation signal is an electrical signal having a different frequency for each of the plurality of in-home terminal devices,
The activation signal monitoring unit includes a filter that allows an electric signal having an arbitrary frequency to pass therethrough, and determines that the activation signal that has passed through the filter is a signal addressed to the own device. The in-home terminal device according to claim 2,
The activation signal is transmitted as an optical signal having a wavelength different from that of the data signal,
The wake-up signal is separated from another optical signal by the wavelength demultiplexing unit in the state of an optical signal. The in-home terminal device according to claim 5,
The activation signal is an electrical signal having a different bit pattern for each of the plurality of residential terminal devices,
The activation signal monitoring unit determines an activation signal having the same bit pattern as the bit pattern assigned to the own device as a signal addressed to the own device. The station-side termination device in a passive optical network system in which a plurality of in-house termination devices are connected via a station-side termination device and an optical splitter,
An activation signal generation unit that generates an activation signal for activating at least one of the plurality of in-home terminal devices from a sleep state using an electrical signal;
An electrical / optical converter that converts the electrical signal of the startup signal generated by the startup signal generator into an optical signal and outputs the optical signal;
A wavelength demultiplexing unit that multiplexes and demultiplexes the optical signal output from the electrical / optical conversion unit and other optical signals according to the wavelength;
The station-side termination device, wherein the activation signal generation unit generates the activation signal at a frequency lower than a data signal transmitted and received between the station-side termination device and the in-home termination device. The station-side terminating device according to claim 7,
The activation signal generation unit generates the activation signal at a different frequency for each of the plurality of in-home termination devices. The station-side terminating device according to claim 7,
The station-side termination device, wherein the electrical / optical conversion unit converts an electrical signal of the activation signal into an optical signal having a wavelength different from that of the data signal. The station-side termination device according to claim 9, wherein
The activation signal generating unit generates a signal having a different bit pattern for each of the plurality of in-home terminal devices.

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