JP2014121066A - Subscriber-side device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a subscriber-side device which allows for data transmission and reception between the subscriber-side device and a station-side device even in the event of power outage in an area having the subscriber-side device installed therein.SOLUTION: The subscriber-side device connected with the station-side device via an optical fiber comprises: a first power source interface for receiving first power from the outside; a second power source interface for receiving second power from the outside; and a power source function unit which determines the presence or absence of the first power on the basis of a physical quantity relating to the first power and selects the first power or the second power to output the power to the inside.

Description

  The present invention relates to a subscriber-side device that is connected to a station-side device through an optical fiber and transmits / receives data.

  An optical communication system that connects a station-side device and one or more subscriber-side devices via an optical fiber branched by a passive element such as an optical branching device is called a PON system (Passive Optical Network). The PON system is one of access methods for optical subscribers applied to FTTH (Fiber To The Home), FTTB (Fiber To The Building), and the like, and is rapidly spreading due to the high speed and economical efficiency of communication. .

  In the PON system as described above, the subscriber side device generally includes a DC power interface, and operates by receiving DC power converted from AC power supplied from commercial power by an AC adapter.

  Japanese Patent Application Laid-Open No. 2004-228688 discloses a USB (Universal Serial Bus) interface instead of a DC power interface, which receives DC power and transmits / receives data using the USB interface.

JP 2008-160197 A

  By the way, such a PON system generally connects a station side apparatus and a subscriber side apparatus with an optical fiber having a maximum length of about 20 km, and a power failure occurs in an area where the subscriber side apparatus is installed. Even so, since the area where the station side device is installed is not always out of power, it is assumed that the optical signal from the station side device reaches the subscriber side device. However, if a power failure occurs in the area where the subscriber side device is installed and the commercial power supply cannot supply AC power, the subscriber side device cannot receive DC power from the AC adapter and stops operating. However, there is a problem that data cannot be transmitted / received to / from the station-side apparatus even though the optical signal has arrived from the station-side apparatus.

  In addition, since Patent Document 1 receives DC power and transmits / receives data using a USB interface, when an external device equipped with a built-in battery such as a notebook computer is connected to the USB interface, the subscriber side The device can operate during a power failure. However, when an external device that does not have a built-in battery is connected to the USB interface, the external device stops operating when the area where the subscriber-side device is installed stops, so the subscriber-side device is disconnected from the external device. It is impossible to receive DC power using the USB interface, and the operation is stopped. Similarly, data cannot be transmitted / received to / from the station side device even though the optical signal has arrived from the station side device. There was a problem.

  The present invention has been made to solve the above-described problems, and an object thereof is to transmit / receive data to / from a station-side device even if a power failure occurs in an area where a subscriber-side device is installed. To obtain a subscriber side device.

  A subscriber-side device according to the present invention is connected to a station-side device via an optical fiber, transmits and receives data to and from the station-side device, and receives a first power from the outside. A second power interface unit for receiving the second power from the outside, and the presence or absence of the first power based on a physical quantity related to the first power, and the first power or the second power And a power supply function unit that selects one of the powers and outputs the power to the inside.

  The present invention determines the presence or absence of power received by the first power interface unit based on a physical quantity related to power received by the first power interface unit, and receives power received by the first power interface unit or second power Since one of the power received by the power interface unit is selected and the necessary power is output inside the subscriber side device, even if the area where the subscriber side device is installed fails, the station side There is an effect that data can be transmitted to and received from the apparatus.

It is a system configuration | structure figure of the PON system in Embodiment 1 thru | or 3 of this invention. It is a block diagram of the subscriber side apparatus in Embodiment 1 thru | or 3 of this invention. It is the flowchart which showed operation | movement of the subscriber side apparatus in Embodiment 2 of this invention. It is the flowchart which showed operation | movement of the subscriber side apparatus in Embodiment 3 of this invention.

Embodiment 1 FIG.
FIG. 1 is a diagram showing a system configuration of a PON system according to Embodiment 1 of the present invention. In FIG. 1, a station side apparatus 1 is connected to subscriber side apparatuses 4a to 4n via an optical fiber 3 branched by an optical branching element 2 to constitute a PON system. The external devices 5a to 5n connected to the subscriber side devices 4a to 4n respectively transmit / receive data to / from the network 6 connected to the upper side of the station side device 1 via the PON system.

  FIG. 2 is a diagram showing the configuration of the subscriber side device 4 according to Embodiment 1 of the present invention. In FIG. 2, a subscriber side device 4 includes a PON interface unit 7 for connecting an optical fiber 3, an optical transmission / reception function unit 8 for converting an optical signal and an electrical signal, and a station side device 1 in accordance with a predetermined standard. PON function unit 9 that transmits / receives data and control signals to / from, UNI function unit 10 that transmits / receives data to / from external device 5, local area network interface unit 11 connected to external device 5, and PON function unit 9 in response to requests from PON function unit 9 A data buffer function unit 12 (storage unit) that performs input / output and storage, and a USB interface unit 14 that connects a battery 13 that outputs DC power (second power, here the voltage of the DC power is 5 V) ( A second power interface unit), a USB power receiving unit 15 that converts the voltage of the power input from the USB interface unit 14, A commercial power supply interface unit 17 (first power supply interface unit) for connecting an AC adapter 16 that converts AC power supplied from the power source into DC power (first power, here the voltage of the DC power is 12V) ) And the DC power output from the commercial power supply interface unit 17 or the DC power output from the USB power supply unit 15 based on the voltage of the power received by the commercial power supply interface unit 17, and if necessary The power supply function part 18 which converts into the electric power suitable for each function part inside the subscriber side apparatus 4, and outputs it to each function part is comprised.

  Next, the operation will be described. When the area where the subscriber side device 4 is installed has a power failure (hereinafter referred to as a power failure), the USB interface unit 14 is connected to the USB interface unit 14 so that the USB interface unit 14 outputs the direct current output from the battery 13. The power is received and output to the USB power receiving unit 15. The USB power receiving unit 15 boosts the voltage of the DC power output from the USB interface unit 14 to 12 V and outputs the boosted voltage to the power function unit 18. The power supply function unit 18 selects the DC power boosted by the USB power supply / reception unit 15, converts it to power suitable for each function unit inside the subscriber side device 4 as necessary, and outputs it to each function unit.

  On the other hand, in the area where the subscriber side device 4 is installed, when the commercial power supply supplies AC power (hereinafter referred to as “no power failure”), the commercial power interface unit 17 supplies the commercial power via the AC adapter 16. DC power converted from AC power to be received is received and output to the power supply function unit 18. The power supply function unit 18 disables the boost function of the USB power supply power reception unit 15, selects the DC power output from the commercial power supply interface unit 17, and power suitable for each function unit in the subscriber side device 4 as necessary. And output to each functional unit.

  Table 1 summarizes the power supply selection conditions of the power supply function unit 18.

  Here, when the area where the subscriber side device 4 is installed changes from a non-power failure to a power failure, the power function unit 18 detects that the voltage of the DC power received by the commercial power interface unit 17 is 0V, The boosting function of the USB power receiving unit 15 is enabled, the DC power boosted by the USB power receiving unit 15 is selected, and converted into power suitable for each functional unit inside the subscriber side device 4 as necessary. Output to the functional part. Note that the power supply function unit 18 may detect that the voltage is lower than a predetermined voltage instead of 0V. Further, the power supply function unit 18 prevents currents from flowing into each other when a voltage difference occurs between the DC power output from the commercial power interface unit 17 and the DC power boosted by the USB power receiving unit 15. You may make it provide a backflow prevention function.

As described above, in the first embodiment, the presence or absence of the power received by the commercial power interface unit 17 is determined based on the voltage of the power received by the commercial power interface unit 17, and the power received by the commercial power interface unit 17 or Since any one of the power received by the USB interface unit 14 is selected and the necessary power is output inside the subscriber side device 4, even if the area where the subscriber side device 4 is installed has a power failure There is an effect that data can be transmitted / received to / from the station side device.
When the power function unit 18 detects that the power received by the commercial power interface unit 17 is equal to or lower than a predetermined voltage, the power function unit 18 enables the boost function of the USB power receiver 15 and boosts the power by the USB power receiver 15. Since the required power is selected and necessary power is generated in the subscriber side device 4 and output to each functional unit, the power of the battery 13 is not consumed at the time of non-power failure, and a power failure occurs. At this time, there is an effect that the subscriber side device 4 can automatically continue the operation by using the power boosted by the USB power receiving unit 15.

  In the first embodiment, the presence or absence of power received by the commercial power interface unit 17 is determined based on the voltage of power received by the commercial power interface unit 17, and the power received by the commercial power interface unit 17 or the USB interface The power received by the unit 14 is selected, but the power received by the commercial power interface unit 17 is not based on the voltage of the power received by the commercial power interface unit 17 but based on a physical quantity related to other power, for example, current. The power received by the commercial power interface unit 17 or the power received by the USB interface unit 14 may be selected.

Embodiment 2. FIG.
In the second embodiment, at the time of a power failure, among the plurality of connection methods between the subscriber side device 4 and the external device 5, the connection method with the largest power consumption is invalidated so that the subscriber side by the battery 13 at the time of the power failure A configuration that makes it possible to extend the operation time of the device 4 will be described.

  Since the system configuration of the PON system and the configuration of the subscriber side device 4 in the second embodiment of the present invention are the same as those in the first embodiment, description thereof will be omitted.

  FIG. 3 is a flowchart showing the operation of the subscriber side device 4 according to the second embodiment of the present invention.

  Next, the operation will be described. When the subscriber side device 4 is activated, the PON function unit 9 is based on the control from the station side device 1 at all link speeds in the PHY device (communication interface unit, not shown) of the UNI function unit 10. Enable auto-negotiation for. Here, it is assumed that auto-negotiation in 10BASE-T, 100BASE-TX, and 1000BASE-T is set to be valid.

Here, the case where there is a change in the AC power supplied from the commercial power supply in the area where the subscriber side device 4 is installed will be described with reference to FIG. When there is a change in the AC power supplied by the commercial power supply in the area where the subscriber side device 4 is installed, the power supply function unit 18 detects the presence or absence of the DC power input via the commercial power supply interface unit 17. (ST20), a DC12V power supply state detection signal indicating the presence or absence of DC power is sent to the PON function unit 9, and the PON function unit 9 determines the presence or absence of DC power from the DC12V power supply detection signal (ST21).
When the DC power is present, the PON function unit 9 sets 1000BASE-T (specifically, 1000BASE-T) having the fastest link speed among all link speeds in the PHY device auto-negotiation setting of the UNI function unit 10. Full / HALF-duplex Capability) is set to be valid (ST22).
On the other hand, when there is no DC power, the PON function unit 9 sets 1000BASE-T (specifically, 1000BASE-T) having the fastest link speed among all link speeds in the PHY device auto-negotiation setting of the UNI function unit 10. -T Full / HALF-duplex Capability) is set to invalid (ST23).
After setting 1000BASE-T to be valid or invalid according to the presence or absence of DC power, the PON function unit 9 auto-negotiates to the PHY device of the UNI function unit 10 after completing the setting of the auto-negotiation of the PHY device of the UNI function unit 10. Is restarted (ST24). After the auto negotiation between the PHY device of the UNI function unit 10 and the external device 5 is completed, the PON function unit 9 reads out the result of auto negotiation (ST25), and the data communication interface of the PON function unit 9 and the UNI function unit 10 The negotiation result is reflected (ST26).

  The power consumption of the PHY device of the UNI function unit 10 becomes smaller when the link speed with the external device 5 is slower. With the above-described operation, the upper limit of the link speed of the PHY device of the UNI function unit 10 is 1000 Mbps at the time of non-power failure and 100 Mbps at the time of power failure, so the power consumption of the PHY device of the UNI function unit 10 is non-power failure. The power outage will be smaller than the time.

  Thus, in this Embodiment 2, since the upper limit of the link speed with the external device 5 at the time of a power failure was restricted, in addition to the effect of Embodiment 1, the subscriber side apparatus by the battery 13 at the time of a power failure There is an effect that the operation time of 4 can be extended.

  In the second embodiment, the subscriber side device 4 and the external device 4 are described as being connected at a link speed of 10BASE-T, 100BASE-TX, or 1000BASE-T. If the person side device 4 and the external device 4 are connected by any one of a plurality of methods having different power consumption, the same effect can be obtained. For example, the subscriber side device 4 and the external device 4 are connected by a wireless LAN compliant with IEEE 802.11, and are connected in accordance with any of the standards of IEEE 802.11b, IEEE 802.11g, and IEEE 802.11n. In the device, the operation time of the subscriber side device 4 by the battery 13 at the time of the power failure can be extended by invalidating the connection by IEEE802.11n having the fastest link speed at the time of the power failure. Further, for example, in the case where the subscriber side device 4 and the external device 4 are connected by a method of transmitting data with the intensity of any one of a plurality of values according to the state of the transmission path, etc. By invalidating the method of transmitting data at the intensity of the largest value among a plurality of values at the time of a power failure, the operation time of the subscriber side device 4 by the battery 13 at the time of the power failure can be extended.

  Further, in the second embodiment, the case where the area in which the subscriber side device 4 is installed is unpowered when the subscriber side device 4 is started up is explained. The validity or invalidity of the connection with the fastest link speed may be set based on the presence or absence of DC power input via the power interface unit 17. In this case, when the subscriber side device 4 is activated, if the area where the subscriber side device 4 is installed is a power failure, the connection with the fastest link speed is invalidated without waiting for control from the station side device 1. There is an effect that it is possible to set.

Embodiment 3 FIG.
In Embodiment 3, it is possible to extend the operation time of the subscriber side device 4 by the battery 13 at the time of a power failure by operating the data buffer function unit 12 in the power saving mode at the time of a power failure. explain.

  The configuration of the system configuration of the PON system according to the third embodiment of the present invention is the same as that of the first embodiment, and thus the description thereof is omitted.

  The system configuration of the PON system in the third embodiment of the present invention is the same as that in the first embodiment. However, in the third embodiment of the present invention, the data buffer function unit 12 includes a DDR memory (not shown) which is a kind of dynamic memory that requires refresh (data holding operation) based on a clock supplied from the outside. Used to accumulate data.

  FIG. 4 is a flowchart showing the operation of the subscriber side device 4 according to Embodiment 3 of the present invention.

Next, the case where there is a change in the AC power supplied from the commercial power supply in the area where the subscriber side device 4 is installed will be described with reference to FIG. When there is a change in the AC power supplied by the commercial power supply in the area where the subscriber side device 4 is installed, the power supply function unit 18 detects the presence or absence of the DC power input via the commercial power supply interface unit 17. (ST30) A DC12V power supply state detection signal indicating the presence or absence of DC power is sent to the PON function unit 9, and the PON function unit 9 determines the presence or absence of DC power from the DC12V power supply detection signal (ST31).
When there is no DC power, the PON function unit 9 monitors a buffer (not shown) for storing data received from the UNI function unit 10 (ST32) and stores the data stored in the buffer. The presence or absence is determined (ST33).
When the accumulation amount of the buffer of the PON function unit 9 is 0, it is assumed that there is no data received from the UNI function unit 10, and the DDR memory of the data buffer function unit 12 is self-refreshed (operates with the power saving mode enabled) ( ST34). By performing the self-refresh operation, the DDR memory performs a refresh operation based on a clock inside the DDR memory, not a clock supplied from the outside. In this case, the DDR memory does not require an external clock.
On the other hand, when the DC power is present and when the buffer accumulation amount of the PON function unit 9 is not 0, the self-refresh operation of the DDR memory included in the data buffer function unit 12 is canceled (power saving mode is invalid) (ST35), and the external To refresh based on the clock supplied from.

  When the DDR memory of the data buffer function unit 12 is subjected to a self-refresh operation, it is not necessary to supply a clock from the outside of the DDR memory, so that the power consumption of the subscriber side device 4 is reduced. As a result of the above-described operation, the DDR memory of the data buffer function unit 12 is released from the self-refresh operation at the time of a non-power failure, and becomes the self-refresh operation at the time of a power failure. The power outage will be smaller than the time.

As described above, in the third embodiment, the data holding operation is performed in either the power saving mode valid or invalid based on the presence / absence of data transmitted from the external device at the time of a power failure. In addition to the above effect, there is an effect that the operation time of the subscriber side device 4 by the battery 13 at the time of a power failure can be extended.

DESCRIPTION OF SYMBOLS 1 Station side apparatus 2 Optical branching element 3 Optical fiber 4 Subscriber side apparatus 5 External apparatus 6 Network 7 PON interface part 8 Optical transmission / reception function part 9 PON function part 10 UNI function part 11 Local area network interface part 12 Data buffer function part 13 Battery 14 USB interface unit 15 USB power receiving unit 16 AC adapter 17 Commercial power interface unit 18 Power function unit

Claims (6)

In the subscriber-side device that is connected to the station-side device via an optical fiber and transmits and receives data to and from the station-side device,
A first power interface unit for receiving first power from the outside;
A second power interface unit for receiving second power from the outside;
A power function unit that determines the presence or absence of the first power based on a physical quantity related to the first power, selects either the first power or the second power, and outputs the power internally; A subscriber-side device. The power supply function unit
If the voltage of the first power is greater than a predetermined voltage, select the first power;
The subscriber side device according to claim 1, wherein when the voltage of the first power is equal to or lower than the predetermined voltage, the second power is selected. A communication interface unit connected to any one of a plurality of different methods of power consumption with an external device that transmits and receives data to and from the station side device;
The communication interface unit
It is possible to select either valid or invalid for a predetermined method with the largest power consumption among the plurality of methods,
When the power function unit selects the first power, select the predetermined method effectively,
3. The subscriber-side device according to claim 1, wherein when the power supply function unit selects the second power, the predetermined method is invalidated. The communication interface unit
It is connected with one of a plurality of link speeds with an external device that transmits and receives data to and from the station side device,
The communication interface unit
It is possible to select either valid or invalid for the fastest fastest link speed among the plurality of link speeds,
When the power function unit selects the first power, effectively select the fastest link speed,
4. The subscriber side apparatus according to claim 3, wherein when the power supply function unit selects the second power, the fastest link speed is invalidally selected. A storage unit that temporarily holds data transmitted from an external device that transmits and receives data to and from the station side device;
The storage unit
Data retention operation is either enabled or disabled in power saving mode,
When the power supply function unit selects the first power, regardless of the presence or absence of data transmitted from the external device, the data saving operation is performed with the power saving mode disabled,
The data holding operation is performed when the power saving mode is enabled or disabled based on presence or absence of data transmitted from the external device when the power function unit selects the second power. The subscriber side device according to any one of claims 1 to 4. The storage unit
When the power saving mode is enabled, data is retained with the internal clock.
6. The subscriber side device according to claim 5, wherein when the power saving mode is invalid, the data holding operation is performed with an external clock.

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