JP5196595B2 - Optical signal redundancy system, optical signal distribution device, and optical signal redundancy method - Google Patents

Optical signal redundancy system, optical signal distribution device, and optical signal redundancy method Download PDF

Info

Publication number
JP5196595B2
JP5196595B2 JP2010058003A JP2010058003A JP5196595B2 JP 5196595 B2 JP5196595 B2 JP 5196595B2 JP 2010058003 A JP2010058003 A JP 2010058003A JP 2010058003 A JP2010058003 A JP 2010058003A JP 5196595 B2 JP5196595 B2 JP 5196595B2
Authority
JP
Japan
Prior art keywords
optical signal
optical
input
switch
line
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
JP2010058003A
Other languages
Japanese (ja)
Other versions
JP2011193263A (en
Inventor
直浩 大瀧
Original Assignee
Necアクセステクニカ株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Necアクセステクニカ株式会社 filed Critical Necアクセステクニカ株式会社
Priority to JP2010058003A priority Critical patent/JP5196595B2/en
Publication of JP2011193263A publication Critical patent/JP2011193263A/en
Application granted granted Critical
Publication of JP5196595B2 publication Critical patent/JP5196595B2/en
Application status is Active legal-status Critical
Anticipated expiration legal-status Critical

Links

Images

Description

  The present invention relates to an optical signal redundancy system for making an optical line redundant, and an optical signal distribution device and an optical signal redundancy method applied to the optical signal redundancy system.

  In recent optical communication services, not only data communication but also services such as optical telephone and television broadcast distribution are provided. Therefore, it is necessary to avoid stopping the service for many users at the same time for a long time due to damage of the optical cable. Therefore, various methods for increasing the reliability of optical lines have been proposed.

  For example, Patent Document 1 describes an optical distribution redundancy method that can simplify the control by reducing the hardware of only the redundant configuration. In the method described in Patent Document 1, a 2-input 2-output optical switch is used as an optical distribution device. In a normal state, the light distribution device outputs light input from each input line to a different output line. On the other hand, in a state where an abnormality is detected in one of the input lines, the light distribution device equally divides the light input from the other line and outputs it to each output line.

  Patent Document 2 describes a multistage optical branch point-multipoint optical transmission system. The system described in Japanese Patent Laid-Open No. 2004-228561 mitigates the influence on communication due to various failures by arranging optical branch elements and optical fibers in multiple stages between a center apparatus and a user apparatus.

  Patent Document 3 describes an optical multi-branch communication system in which trunk lines of a master station device and an optical splitter are redundantly configured. In the system described in Patent Document 1, when a switching instruction is given, the optical switch switches the transmission line of the main line.

Japanese Patent Laid-Open No. 10-23478 (paragraphs 0020, 0025, 0055) JP-A-8-242207 (paragraphs 0007, 0008, FIG. 1) JP 2002-198404 (paragraphs 0031 and 0032, FIG. 1)

  In recent years, an optical communication service by GE-PON (Gigabit Ethernet Passive Optical Network. Ethernet is a registered trademark) has been provided. In an optical communication service using GE-PON, one optical cable is branched into a plurality of lines by an optical passive element called an optical coupler.

  FIG. 10 is an explanatory diagram showing a configuration of a general optical communication service. In the optical communication service shown in FIG. 10, one optical cable 11 is branched into a plurality of lines by an optical coupler 12, and an OLT (Optical Line Terminal) device 10 disposed in a center station and each user's home. An optical communication line is shared by connecting an ONU (Optical Network Unit) device 13 with a double star system. The merit of the configuration shown in FIG. 10 is that since a plurality of users share the same line, the infrastructure cost can be reduced as compared with the case of connection by a one-to-one single star system.

  Here, the cables used in the optical communication are roughly classified into three according to the locations where they are laid. These are a trunk line connecting the OLT device and the optical coupler, a lead-in wiring connecting the user's home from the optical coupler, and a home wiring connected to the ONU device in the user's home. If the lead-in wiring and the home wiring are cut or damaged for some reason, only one user connected to this wiring cannot use the optical communication. On the other hand, when a line abnormality such as disconnection or breakage occurs on a trunk line shared by a plurality of users due to a disaster or an unexpected accident, all users sharing the trunk line cannot communicate. In this case, the optical communication service becomes unusable, which sometimes becomes a big problem.

  As a disaster or unexpected accident, for example, a utility pole collapses due to a disaster such as an earthquake, a large vehicle accidentally catches an optical cable, or a bird or insect cuts or breaks an optical cable The damage by the thing is assumed. In fact, there have been reports of cases in which optical cables were accidentally cut during road maintenance work, and cases in which an optical cable was cut by a bear-zebra trying to lay eggs on the optical cable.

  If a normal optical communication service is not possible due to an optical line failure, the carrier will identify the faulty part and repair the faulty part as soon as possible, or use another optical cable to cut the section of the optical cable that has been cut or damaged. It was necessary to lay again. In particular, when a main line is damaged, a construction vehicle such as a unic car or an engineer having a technology capable of laying an optical cable is required for re-laying. That is, since it takes various times to complete the repair work, it is difficult to instantaneously restore the optical communication service. Therefore, it is necessary to increase the reliability of the optical line.

  It is generally known that an OLT device has a redundant configuration in preparation for a communication failure of an optical communication service. However, this is a method of maintaining the optical communication service by switching the control to the spare OLT device when the OLT device fails. Therefore, it cannot be said to be an effective means when an abnormality occurs on the optical line.

  With the configurations described in Patent Document 1 and Patent Document 2, it is possible to increase the reliability of the optical line. However, when an optical communication line based on GE-PON is to be realized using the optical distribution device described in Patent Document 1 or the system configuration described in Patent Document 2, there is a problem that its construction is not easy. .

  The configuration described in Patent Document 1 assumes optical communication for video distribution, and this configuration is one-way unidirectional communication. In GE-PON optical communication mainly for data communication, single-fiber bidirectional communication is required. Therefore, the optical amplifier portion described in Patent Document 1 must be bidirectionally compatible. For this reason, when an optical communication system based on GE-PON is configured using the method described in Patent Document 1, there is a problem that the configuration including the optical amplifier portion becomes more complicated.

  Further, when the optical transmission system described in Patent Document 2 is to be realized, the center device and / or the user device must incorporate an optical switch corresponding to the redundant configuration. Thus, when constructing the system described in Patent Document 2, a dedicated device must be prepared, and there is a problem that the construction of the system is not easy.

  SUMMARY OF THE INVENTION An object of the present invention is to provide an optical signal redundancy system and an optical signal distribution device and an optical signal redundancy method applied to the optical signal redundancy system that can easily construct a redundant configuration of an optical communication line.

  An optical signal redundancy system according to the present invention is connected to a plurality of input lines to which an optical signal is input, and distributes an optical signal input from one input line selected from the input lines to a plurality of output lines. A plurality of optical signal distribution devices, each of which is a switch for selecting one of the input lines to which the optical signal is input, and the input line selected by the switch Light receiving power monitoring means for monitoring the light receiving power of the optical signal input from the switch, switch switching means for switching the input line to be selected by the switch when there is an abnormality in the light receiving power of the optical signal, and the input line via the switch Optical signal distribution means for distributing and transmitting optical signals received from a plurality of output lines, and one input line in each optical signal distribution apparatus is connected to another optical signal distribution apparatus. It is connected to an output line, one output line of each optical signal distribution apparatus, and being connected to one input line in the other optical signal distributor.

  An optical signal distribution device according to the present invention is connected to a plurality of input lines to which an optical signal is input, and distributes an optical signal input from one input line selected from the input lines to a plurality of output lines. An optical signal distribution device for transmitting an optical signal, wherein a switch that selects any one of a plurality of input lines to which an optical signal is input, and an optical signal input from the input line selected by the switch Light reception power monitoring means for monitoring the light reception power, switch switching means for switching the input line to be selected by the switch when there is an abnormality in the light reception power of the optical signal, and a plurality of optical signals received from the input line via the switch Optical signal distribution means for distributing and transmitting to the output line of the optical signal, and one input line in the optical signal distribution apparatus itself is connected to one output line in the other optical signal distribution apparatus Is one of the output lines in the optical signal distributor itself, characterized in that it is connected to one input line in the other optical signal distributor.

  An optical signal redundancy method according to the present invention is connected to a plurality of input lines to which an optical signal is input, and distributes an optical signal input from one input line selected from the input lines to a plurality of output lines. In the optical line redundancy method using a plurality of optical signal distribution apparatuses that transmit the optical signals, one input line in each optical signal distribution apparatus is connected to one output line in another optical signal distribution apparatus, and each optical signal One output line in the distribution device is connected to one input line in another optical signal distribution device, and each optical signal distribution device monitors the light receiving power of the optical signal input from the selected input line, and When the signal distribution device has an abnormality in the light receiving power of the optical signal input from the input line, the switch that selects the connection destination of the input line switches the input line, and each optical signal distribution device passes through the switch. Input line And transmits and distributes the received optical signal into a plurality of output lines.

  According to the present invention, a redundant configuration of an optical communication line can be easily constructed.

It is explanatory drawing which shows the example of the optical line redundant configuration apparatus in the 1st Embodiment of this invention. It is explanatory drawing which shows the structural example of the optical communication system in 1st Embodiment. It is a flowchart which shows the operation example of the redundant structure in 1st Embodiment. It is explanatory drawing which shows the other structural example of the optical communication system in 1st Embodiment. It is explanatory drawing which shows the example of the optical line redundant configuration apparatus in the 2nd Embodiment of this invention. It is explanatory drawing which shows the structural example of the optical communication system in 2nd Embodiment. It is a flowchart which shows the operation example of the redundant structure in 2nd Embodiment. It is explanatory drawing which shows the example of a relationship of a backup trunk line. It is a block diagram which shows the example of the minimum structure of the optical signal redundant system by this invention. It is explanatory drawing which shows the structure of a general optical communication service.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

Embodiment 1. FIG.
First, the optical line redundant configuration apparatus in the first embodiment will be described. FIG. 1 is an explanatory diagram showing an example of an optical line redundant configuration apparatus in the first embodiment of the present invention. The optical line redundant configuration apparatus illustrated in FIG. 1 is one apparatus in which an optical switch is built in an optical coupler. Hereinafter, the optical line redundant configuration apparatus in the present embodiment is referred to as an optical switch built-in coupler. The optical switch built-in coupler 2 illustrated in FIG. 1 includes an optical switch 3, a light reception monitoring unit 4, an optical cable 5, an optical coupler unit 6, and optical cables 7-1 to 7-n.

  Optical cables 1-1 and 1-2 are externally connected to the optical switch built-in coupler 2 as upper connection lines, and each optical cable is connected to the optical switch 3 inside the optical switch built-in coupler 2. The optical switch 3 is connected to the optical coupler unit 6 via the optical cable 5.

  The optical switch 3 selects any one of the upper connection lines in response to an instruction from the light reception monitoring unit 4 described later. In the example illustrated in FIG. 1, the optical switch 3 selects any one of the optical cable 1-1 and the optical cable 1-2 that are higher-order connection destinations in response to an instruction from the light reception monitoring unit 4 described later.

  In the subsequent stage of the optical cable 5, the optical coupler unit 6 branches the optical cable into n cables from the optical cable 7-1 to the optical cable 7-n. The optical cables 7-1 to 7- (n-1) are led out from the optical switch built-in coupler 2 and connected to a subsequent ONU device (not shown). The optical cable 7-n is a dedicated cable for internal use, and is connected to the light reception monitoring unit 4 inside the optical switch built-in coupler 2.

  Generally, in a GE-PON system, an optical coupler having a 1 to N branch (N is a multiple of 2) is used. The light emitted from the OLT device is N-branched by an optical coupler and transmitted to each ONU device. On the contrary, the light of each ONU device is coupled by an optical coupler and transmitted to the OLT device.

  In general, the OLT device includes the light emission permission information for each ONU device in the optical signal so that the signals of different ONU devices do not collide when the optical signals of each ONU device are combined by the optical coupler unit. To transmit. By transmitting this issuance permission information and managing the time, it becomes possible to connect a plurality of ONU devices to one OLT device and share the same optical line. In this way, the communication method used in the GE-PON system is an optical communication method that assumes video distribution in that an upstream signal exists when branching optical communication and connecting to a plurality of users (for example, This is different from the optical distribution redundancy method described in Patent Document 1.

  The light reception monitoring unit 4 monitors the light reception power of the optical signal emitted from the OLT device (not shown). The optical signal is input from the optical cable 1-1 or the optical cable 1-2 via the optical switch 3, the optical cable 5, and the optical coupler unit 6. When the light reception monitoring unit 4 detects an abnormality in the light reception power, it transmits a switch switching signal to the optical switch 3 to switch the connection destination of the optical cable 5.

  The light reception monitoring unit 4 may detect an abnormality from, for example, fluctuations in the light reception power. As described above, the received light power monitored by the received light monitoring unit 4 is an optical signal that is always emitted by the OLT device. If the light reception path does not change, the light reception monitoring unit 4 receives a stable optical signal. On the other hand, when the received light power fluctuates, it is assumed that there is some abnormality in the path. Therefore, the light reception monitoring unit 4 can detect an abnormality such as a line disconnection by detecting the fluctuation of the light reception power.

  When the received light power fluctuates greatly, it is assumed that the line is damaged even if the line is not cut off. Even in such a case, the light reception monitoring unit 4 may determine that there is an abnormality and switch the switch 3. Even in such a case, by performing the switching process, it is possible to re-lay the damaged optical trunk line even in the operational state.

  Note that the method by which the light reception monitoring unit 4 detects an abnormality is not limited to the method of detecting fluctuations in the light reception power. For example, the received light power at which the ONU device can receive data is set as a threshold value, and the abnormality may be detected when the received light monitoring unit 4 detects an optical signal having a received light power lower than the threshold value. However, the value determined as the threshold value is not limited to the received light power at which the ONU device can receive data.

  In addition, as a method for detecting the abnormality, the light reception monitoring unit 4 includes both a method for determining whether or not a light reception power signal exceeding a threshold value has been received and a method for determining whether or not a fluctuation has occurred in the light reception power. May be used. In this case, if the light reception monitoring unit 4 satisfies any one of the contents (that is, the light reception power signal exceeding the threshold is received or the light reception power fluctuates), the light reception monitoring unit 4 detects the abnormality. Good.

  The light reception monitoring unit 4 is realized by combining a function called RSSI (Received Signal Strength Indication) and a function for managing information such as the intensity of an optical signal measured by RSSI. Since the RSSI for optical signals can determine the intensity of the optical signal from the current value of the optical photodiode, the light reception monitoring unit 4 collects information on the intensity, fluctuates, or reaches a predetermined threshold value. Judge whether or not. For example, when determining whether or not a predetermined threshold value has been reached, the light reception monitoring unit 4 can be realized only by the electric circuit configuration. When determining fluctuation, the light reception monitoring unit 4 is realized by, for example, an IC or a PLD (Programmable Logic Device) having a dedicated function programmed for fluctuation determination. The program may include a process for causing the light reception monitoring unit 4 to execute a process for switching the switch.

  As described above, the optical switch built-in coupler 2 in the present embodiment incorporates the optical switch 3 in the optical coupler for branching the optical cable, so that the optical line route (for example, the optical cables 1-1, 1- 2) can be selected.

  Further, the light reception monitoring unit 4 in the optical coupler detects a change in the light reception power of the optical signal received from the OLT device when the upper optical line is disconnected or damaged. When an abnormality is detected in the light reception power, the light reception monitoring unit 4 prompts the switching of the optical switch 3 and selects a line connection to another optical line route. Therefore, it can be automatically restored in a short time to a state in which optical communication is possible without repairing the failed part or rewiring the optical cable. Therefore, it can be avoided that the optical communication service is stopped for a long time.

  Next, an optical line redundancy method in which an optical line is made redundant using the above-described coupler with a built-in optical switch will be described. FIG. 2 is an explanatory diagram showing a configuration example of an optical communication system using the optical switch built-in coupler 2 illustrated in FIG. The optical communication system illustrated in FIG. 2 includes an OLT device 20, a plurality of ONU devices 29-1 to 29- (n-1), and an optical switch built-in coupler 26. The optical switch built-in coupler 26 corresponds to the optical switch built-in coupler 2 in FIG. Hereinafter, one ONU device selected from the ONU devices 29-1 to 29-(n−1) is referred to as an ONU device 29.

  In the configuration according to the present embodiment, the optical coupler 12 is replaced with the optical switch built-in coupler 26 as compared with the general configuration shown in FIG. The OLT device 20 and the optical switch built-in coupler 26 are connected by two optical cables, an optical cable 23 and an optical cable 24, via an optical cable 21 and a two-branch optical coupler 22. Note that the OLT device 20 and the ONU device 29 are the same as devices used in a general configuration, and thus description thereof is omitted.

  The optical cable 23 is a trunk line that is assumed to be normally used. The individual ONU devices 29 are connected to the OLT device 20 via the optical switch built-in coupler 26 and the optical cable 23, and perform optical communication with each other.

  The optical cable 24 is an optical line laid in advance as a backup trunk line when an abnormality such as cutting or breakage occurs on the optical cable 23.

  The two-branch optical coupler 22 is disposed in the immediate vicinity of the OLT device 20, and the optical switch built-in coupler 26 is disposed in the vicinity of each ONU device 29. As a result of such arrangement, the optical cable 23 corresponding to the trunk line in the total wiring length from the OLT device 20 to the ONU device 29 can be configured to increase.

  Also, with this configuration, there is a high possibility that a situation in which the optical cable is cut or damaged due to a disaster or an unexpected accident occurs on the cable (on the optical cable 23). Further, by dividing the wiring route of the trunk optical cable 23 and the standby trunk optical cable 24, even if a disaster or an unexpected accident occurs on the trunk, it is possible to prevent the spare trunk from being disconnected.

  Next, the operation of the redundant configuration (optical communication system) constructed using the optical switch built-in coupler according to the present embodiment will be described with reference to FIGS. FIG. 3 is a flowchart showing an operation example of the redundant configuration in the present embodiment. It is assumed that the optical switch 25 is in a state where the switch is tilted toward the optical cable 23 used as a trunk line as an initial state. In the following description, it is assumed that the optical signal transmitted from the OLT device 20 always emits light.

  The light reception monitoring unit 27 constantly receives the optical signal from the OLT device 20 transmitted via the optical cable 23, and monitors the light reception power (step S1). In the GE-PON system, the wavelength of the downstream signal is 1490 nm. Therefore, the light reception monitoring unit 27 can monitor only the optical signal emitted from the OLT device 20 by adjusting the wavelength of the monitored light to 1490 nm.

  When the trunk optical cable 23 is cut or damaged due to a disaster or an unexpected accident, the optical signal emitted from the OLT device 20 is not normally transmitted to the coupler with a built-in optical switch. In such a case, when the light reception monitoring unit 27 detects an abnormality in the light reception power (step S2), it transmits an optical switch switching signal (sometimes referred to as a control signal) to the optical switch 25 (step S3). ). When receiving the control signal, the optical switch 25 switches the connection destination of the optical line from the optical cable 23 side to the optical cable 24 side (step S4). The light reception monitoring unit 27 determines whether or not the optical signal emitted from the OLT device 20 has been confirmed by switching the optical cable (step S5).

  If the optical signal can be confirmed (Yes in step S5), the light reception monitoring unit 27 determines that the restoration of the line failure is completed, and ends the process (step S6). In this case, each ONU device 29 can transmit and receive normal optical signals to and from the OLT device 20 via the optical cable 24 that is not cut or damaged again.

  On the other hand, if the optical signal cannot be confirmed even when the switch is switched, the protection trunk line (standby trunk line) may have been cut or damaged, or the OLT device 20 itself may have failed. Therefore, automatic recovery is difficult, and it is necessary to repair the optical line or the OLT device 20 by a person. In this case (No in step S5), the light reception monitoring unit 27 determines that the line failure has not been recovered, and transmits an optical switch switching signal to the optical switch 25 again (step S7). Upon receiving this control signal, the optical switch 25 switches the connection destination of the optical line from the optical cable 24 side to the optical cable 23 side. That is, the light reception monitoring unit 27 returns the optical switch 25 to the original state and ends the process (step S8).

  As described above, in this embodiment, an optical signal input from one upper line selected from the upper lines is distributed to a plurality of output lines by connecting to a plurality of upper lines to which an optical signal is input. A redundant line is configured using the coupler 2 with a built-in optical switch. In addition, the light reception monitoring unit 4 is provided at one of the branches in the optical coupler unit 6, and the light reception monitoring unit 4 monitors the light reception power from the OLT device and changes the connection destination of the optical switch 3. Specifically, the light reception monitoring unit 4 switches the connection destination of the line to another input line when there is an abnormality in the light reception power of the optical signal input from the line to be monitored.

  Thus, since the light reception monitoring unit 4 monitors the light reception power and switches the line, both the OLT device (sometimes referred to as a center device) and the ONU device (sometimes referred to as a user device). There is no need to provide special functions. Therefore, a redundant configuration of the optical communication line can be easily constructed.

  Further, the light reception monitoring unit 4 can monitor the light reception power from the OLT device and change the connection destination of the optical switch 3, thereby automatically switching the optical switch 3 for selecting the upper line when a failure occurs. In other words, the optical switch built-in coupler 2 operates passively and performs line switching in a redundant configuration, so that it is possible to easily construct a redundant configuration that does not require external control from an external device (for example, an OLT device).

  In addition, the coupler with a built-in optical switch in the present embodiment receives an optical signal from the OLT device, detects an abnormality in received light power by itself, and switches to another line. Therefore, no external control is required. That is, the coupler with a built-in optical switch according to the present embodiment only needs to have a function (reception function) for receiving an optical signal from the OLT device, and does not need to have a transmission function. Can be realized.

  Furthermore, since the coupler with a built-in optical switch in the present embodiment detects an abnormal state of the optical line by monitoring the optical signal from the OLT device 20, the optical line can be used even when communication with the OLT device 20 is disabled. Switching control can be executed.

  For example, in general, when a line abnormality is confirmed, it is necessary to identify an abnormal part and then repair or re-lay an optical cable in the abnormal section. Usually, the restoration work requires a lot of time and work, so the optical communication service may be stopped for a long time. However, by using the coupler with a built-in optical switch in the present embodiment, it is possible to obtain an effect that the line failure can be automatically recovered in a short time (for example, several seconds) from the communication failure due to the optical line abnormality.

  Next, a modification of the optical communication system in the present embodiment will be described. FIG. 4 is an explanatory diagram illustrating a configuration example of an optical communication system according to the present modification. The optical communication system in this modification includes an OLT device 30, a plurality of ONU devices 39-1 to 39- (n-2), 44-1 to 44- (n-2), optical cables 33 and 34, and an optical switch. And built-in couplers 36 and 41. Hereinafter, one ONU device selected from ONU devices 39-1 to 39- (n-2) is referred to as ONU device 39 and selected from ONU devices 44-1 to 44- (n-2). One ONU device is referred to as an ONU device 44.

  The optical switch built-in couplers 36 and 41 in this modification are the same as the optical switch built-in coupler 2 in FIG. 1, and the light reception monitoring units 37 and 42 are the same as the light reception monitoring unit 4 in FIG. The optical switches 35 and 40 in the present embodiment are the same as the optical switch 3 in FIG. 1, and the optical coupler units 38 and 43 are the same as the optical coupler unit 6 in FIG.

  In the optical communication system in this modification, two optical switch built-in couplers 36 and 41 are used. The optical cable 33 is a trunk line that is assumed to be normally used for the ONU device 39. The optical cable 34 is a trunk line that is assumed to be normally used for the ONU device 44.

  Unlike the above-described embodiment, the standby trunk line of the optical switch built-in coupler 36 (here, the optical cable 45) is connected to one of the branches of the other optical switch built-in coupler 41 (that is, the optical coupler unit 43). Similarly, the standby trunk line of the optical switch built-in coupler 41 (here, the optical cable 46) is also connected to one of the branches of the optical switch built-in coupler 36 (that is, the optical coupler unit 38).

  Note that the OLT device 30 and the ONU devices 39 and 44 are the same as devices used in a general configuration, and thus description thereof is omitted.

  In the configuration illustrated in FIG. 4, when a line abnormality occurs on the optical cable 33 that is a trunk line, the light reception monitoring unit 37 detects the abnormality of the light reception power and switches the optical switch 35 to change the connection destination of the upper line to the optical cable. The optical cable 45 of the standby trunk line is changed from 33. As a result, the optical switch built-in coupler 36 is reconnected to the subsequent stage of the optical switch built-in coupler 41. Therefore, each ONU device 39 in which a communication failure has occurred transmits and receives signals to and from the OLT device 30 via the trunk optical cable 34, the optical switch built-in coupler 41, the standby trunk optical cable 45, and the optical switch built-in coupler 36. It becomes possible and can be restored automatically.

  Similarly, when a line abnormality occurs on the optical cable 34 that is a trunk line, the light reception monitoring unit 42 detects an abnormality in the light reception power and switches the optical switch 40 to change the connection destination of the higher line from the optical cable 34 to the standby trunk line. Change to optical cable 46. As a result, the optical switch built-in coupler 41 is reconnected to the subsequent stage of the optical switch built-in coupler 36. Therefore, each ONU device 44 in which a communication failure has occurred transmits and receives signals to and from the OLT device 30 via the trunk optical cable 33, the optical switch built-in coupler 36, the standby trunk optical cable 46, and the optical switch built-in coupler 41. It becomes possible and can be restored automatically.

  As described above, also in this modified example, the optical signal input from one upper line selected from the upper lines is connected to the plurality of upper lines to which the optical signal is input, and the plurality of output lines are connected. A redundant line is configured using a plurality of optical switch built-in couplers 36 and 41 that distribute and transmit. At this time, the optical switch built-in coupler 36 connects one of the output lines of the optical switch built-in coupler 41 to an optical cable 45 different from the optical cable 33 which is a trunk line. Similarly, the optical switch built-in coupler 41 connects one of the output lines of the optical switch built-in coupler 36 to an optical cable 46 different from the optical cable 34 which is a trunk line.

  The light reception monitoring unit 37 of the optical switch built-in coupler 36 monitors the light reception power of the optical signal input from the optical cable 33 which is a trunk line. When there is an abnormality in the light reception power of the optical signal input from the optical cable 33, the light reception monitoring unit 37 switches the optical switch 35 to the optical cable 45 which is another input line and connects it. Then, the optical coupler unit 38 distributes the optical signal received from the optical cable 45 via the optical switch 35 to a plurality of output lines and transmits it to the ONU device 39.

  That is, by using two optical switch built-in couplers in the present embodiment and connecting the standby trunk optical cable connected to each optical switch built-in coupler to each branch, the redundancy of the optical communication line protecting each other's trunk line You can build a configuration. In particular, when a new protection line is laid, an optical switch built-in coupler according to the present invention is installed in an existing laid optical line so that the existing two-branch optical coupler 32 can be used to newly lay the protection line. The optical line can be branched. That is, a redundant configuration can be constructed without changing the two-branch optical coupler 32 to another product.

  That is, in order to construct a redundant configuration, a redundant configuration can be easily constructed only by preparing a configuration for connecting couplers with built-in optical switches or connecting a coupler with built-in optical switch and another coupler.

  Further, when the installation distance of the couplers 36 and 41 with built-in optical switches is sufficiently shorter than the lengths of the optical cables 33 and 34, the length of the optical cable newly laid can be reduced by installing the coupler with built-in optical switch in the present invention. It can be shortened.

Embodiment 2. FIG.
FIG. 5 is an explanatory diagram showing an example of an optical line redundant configuration apparatus in the second embodiment of the present invention. The optical line redundant configuration apparatus illustrated in FIG. 5 also has an optical switch built in the optical coupler, as in the first embodiment. Hereinafter, the optical line redundant configuration apparatus in this embodiment is also referred to as an optical switch built-in coupler. The optical switch built-in coupler 51 illustrated in FIG. 5 includes an optical switch 53, a light reception monitoring unit 54, an optical cable 55, an optical coupler unit 56, and optical cables 57-1 to 57-n.

  In the first embodiment, a case has been described in which the optical switch built-in coupler 2 illustrated in FIG. On the other hand, the coupler 51 with a built-in optical switch illustrated in FIG. 5 is different from the coupler 2 with a built-in optical switch in that four upper connection lines are connected from the outside. The rest is the same as in the first embodiment.

  That is, the optical switch 3 of the coupler 2 with built-in optical switch illustrated in FIG. 1 has one circuit and two contacts, whereas the optical switch 53 illustrated in FIG. 5 employs a switch with one circuit and four contacts. However, the number of contacts connected to the switch is not limited to four contacts, and is not limited to two contacts. The number of contacts to which the switch is connected may be two or more.

  In the example shown in FIG. 5, optical cables 50-1 to 50-4 are connected to the optical switch built-in coupler 51 from the outside as upper connection lines, and each optical cable is connected to the optical switch 53 inside the optical switch built-in coupler 51. Connected. The optical switch 53 is connected to the optical coupler unit 56 via the optical cable 55.

  Further, the optical switch 3 and the optical switch 53 illustrated in FIG. 1 correspond to each other, and the light reception monitoring unit 4 and the light reception monitoring unit 54 illustrated in FIG. 1 correspond to each other. Furthermore, the optical coupler unit 6 illustrated in FIG. 1 and the optical coupler unit 56 correspond to each other, and the optical cables 5 and 7-1 to 7-n illustrated in FIG. 1, the optical cables 55 and 57-1 to 57-n, Corresponds. A description of these corresponding configurations is omitted. In the following description, a case where the number of contacts connected to the optical switch is four contacts will be described.

  FIG. 6 is an explanatory diagram showing a configuration example of an optical communication system using the optical switch built-in coupler 51 illustrated in FIG. The optical communication system illustrated in FIG. 6 is also a connection example for the purpose of automatic recovery from a communication failure. The optical communication system illustrated in FIG. 6 includes an OLT device 60 and optical switch built-in couplers 67 and 69 to 71. Since the contents of the optical switch built-in couplers 69 to 71 are the same as the contents of the optical switch built-in coupler 67, the description thereof is omitted.

  The optical switch built-in coupler 67 includes an optical switch 68. The optical switch built-in coupler 67 includes a light reception monitoring unit (not shown). The light reception monitoring unit (not shown) provided in the optical switch built-in coupler 67 is the same as the light reception monitoring unit 4 in FIG. The optical signal input to the optical switch built-in coupler 67 is transmitted to, for example, a plurality of ONU devices (not shown) via the optical switch 68. However, in FIG. 6, description is abbreviate | omitted regarding the optical cable branched by the couplers 67 and 69-71 with an optical switch, and the connection of the optical cable and ONU apparatus connected to a back | latter stage.

  The OLT device 60 is connected to the optical cable 61. The optical cable 61 is connected to a four-branch optical coupler 62. The four-branch coupler 62 is connected to optical switch built-in couplers 67, 69, 70, and 71 via optical cables 63, 64, 65, and 66, respectively.

  For example, in the optical switch built-in coupler 67, one contact of the optical switch 68 having four contacts is connected to the main line (optical cable 63). Then, one of the remaining three contacts is connected to the optical cable 72, which is one of the lines branched by the coupler 69 with built-in optical switch, in the same manner as the connection method shown in the modification of the first embodiment. By doing so, it becomes a backup trunk line. Similarly, the remaining contacts are connected to an optical cable 73, which is one of the optical cable lines branched by the optical switch built-in coupler 70, and an optical cable 74, which is one of the optical cable lines branched from the optical switch built-in coupler 71. , Make it a backup trunk line.

  Next, the operation of the redundant configuration (optical communication system) constructed using the optical switch built-in coupler according to the present embodiment will be described with reference to FIGS. FIG. 7 is a flowchart illustrating an example of operation in a redundant configuration. It is assumed that the optical switch 68 is in a state where the switch is tilted toward the optical cable 63 used as a trunk line as an initial state.

  The light reception monitoring unit in the optical switch built-in coupler 67 constantly receives the optical signal from the OLT device 60 transmitted via the optical cable 63 and monitors the light reception power (step S10). When the light reception monitoring unit detects a light reception power abnormality (step S11), it transmits an optical switch switching signal to the optical switch 68 (step S12). The light reception monitoring unit switches the contact of the optical switch 68 to the optical cable 72 (step S13).

  The light reception monitoring unit determines whether or not the light reception power of the optical signal normally emitted from the OLT device 60 via the optical cable 64 and the optical cable 72 can be confirmed by switching the optical cable (step S14). When the light reception power of the optical signal can be confirmed (Yes in step S14), the light reception monitoring unit determines that the recovery from the line failure is completed and ends the process (step S15).

  On the other hand, when the light reception power of the optical signal cannot be confirmed (No in step S14), the light reception monitoring unit further transmits an optical switch switching signal to the optical switch 68 (step S16). Then, the light reception monitoring unit switches the contact point of the optical switch 68 to the optical cable 73 (step S17) and attempts automatic recovery.

  The light reception monitoring unit determines whether or not the light reception power of the optical signal normally emitted from the OLT device 60 via the optical cable 65 and the optical cable 73 has been confirmed by switching the optical cable (step S18). When the light reception power of the optical signal can be confirmed (Yes in step S18), the light reception monitoring unit determines that the restoration of the line failure is completed and ends the process (step S15).

  If the light reception power of the optical signal cannot be confirmed (No in step S18), the light reception monitoring unit further transmits an optical switch switching signal to the optical switch 68 (step S19). Then, the light reception monitoring unit switches the contact point of the optical switch 68 to the optical cable 74 (step S20) and attempts automatic recovery.

  The light reception monitoring unit determines whether or not the light reception power of the optical signal normally emitted from the OLT device 60 via the optical cable 66 and the optical cable 74 has been confirmed by switching the optical cable (step S21). When the light reception power of the optical signal can be confirmed (Yes in step S21), the light reception monitoring unit determines that the recovery from the line failure is completed and ends the process (step S15).

  If the received light power of the optical signal cannot be confirmed (No in step S21), that is, if it has not been confirmed that it has been automatically restored, there is a possibility that all the optical lines are faulty or the OLT device 60 itself has failed. Therefore, automatic recovery is difficult and human repair work is required. In this case, the light reception monitoring unit transmits an optical switch switching signal to the optical switch 68 (step S22). When receiving the control signal, the optical switch 68 switches the connection destination of the optical line to the optical cable 63. That is, the light reception monitoring unit returns the optical switch 68 to the initial state and ends the process (step S23).

  As for the optical switch built-in couplers 69, 70, 71, similarly to the optical switch built-in coupler 67, the optical cable in which the upper line (specifically, the contact point of the optical switch) is branched by the other optical switch built-in coupler 70. A spare trunk line can be prepared by connecting to one of the lines.

  FIG. 8 is an explanatory diagram showing an example of the relationship between the backup trunk lines. The optical cables 63 to 66 illustrated in FIG. 6 correspond to the optical cables 83 to 86, and the optical switch built-in couplers 67 and 69 to 71 illustrated in FIG. 6 correspond to the optical switch built-in couplers 87 to 90. In addition, backup trunk routes 91 to 96 represent optical cables that are connected when the optical switch is switched.

  In the example of FIG. 8, the backup trunk routes 91 to 96 are represented by bidirectional arrows. This means two optical cables and means that the optical cables are made redundant in both directions. The spare trunk line in FIG. 8 is a pair of bidirectional arrows (that is, an optical cable).

  For example, in the backup trunk route 91, an arrow from the optical switch built-in coupler 87 toward the optical switch built-in coupler 88 corresponds to the optical cable 72 illustrated in FIG. Further, in the backup trunk route 93, the arrow from the optical switch built-in coupler 87 to the optical switch built-in coupler 90 corresponds to the optical cable 74 illustrated in FIG. The arrow toward the built-in coupler 89 corresponds to the optical cable 73 illustrated in FIG.

  In the configuration example illustrated in FIG. 6, the optical cable corresponding to the other arrow in the backup trunk routes 91, 93, and 95 in FIG. 8 and the optical cable corresponding to both arrows in the backup trunk routes 92, 94, and 96 are shown. Is omitted. Specifically, the optical cables corresponding to these arrows are optical cables connected to optical switches (not shown) of the optical switch built-in couplers 69 to 71, and correspond to the optical cables 72 to 74.

  In this manner, by connecting the upper line of each optical switch built-in coupler to one of the optical cable lines branched by another optical switch built-in coupler, a bidirectional backup trunk route can be secured. Therefore, for example, even if three lines of the main line (optical cables 83, 84, 85, 86) have a line abnormality at the same time, automatic recovery is possible.

  Next, an example of the minimum configuration of the optical signal redundancy system according to the present invention will be described. FIG. 9 is a block diagram showing an example of the minimum configuration of the optical signal redundancy system according to the present invention. The optical signal redundancy system according to the present invention is connected to a plurality of input lines 71 and 72 (for example, optical cables 1-1 and 1-2) to which an optical signal is input, and one input line selected from the input lines. An optical signal distribution device 80 (for example, an optical switch) that distributes and transmits an optical signal input from 71 (for example, an optical cable 1-1) to a plurality of output lines 73 (for example, optical cables 7-1 to 7-n). A plurality of built-in couplers 2) are provided.

  Each optical signal distribution device 80 is selected by the switch 81 (for example, the optical switch 3) that selects any one of the plurality of input lines 71 and 72 to which the optical signal is input, and the switch 81. The received light power monitoring means 82 (for example, the received light monitoring unit 4) that monitors the received light power of the optical signal input from the input line, and when the received light power of the optical signal is abnormal (for example, the received light power fluctuates) And when the received light power is less than the threshold), switch switching means 83 (for example, received light monitoring unit 4) for switching the line to be selected by the switch 81, and an optical signal received from the input line via the switch 81 as a plurality of output lines And optical signal distribution means 84 (for example, optical coupler unit 6) for distributing and transmitting to 73.

  One input line 72 in each optical signal distribution device 80 is connected to one output line 73 ′ in another optical signal distribution device 80 ′, and one output line 73 in each optical signal distribution device 80 is connected to another optical signal. It is connected to one input line 72 ′ in the signal distribution device 80 ′.

  With such a configuration, a redundant configuration of an optical communication line can be easily constructed.

  That is, the optical signal distribution device 80 (for example, the coupler 2 with built-in optical switch) is passively controlled by simply monitoring the received light power from the external device without being controlled by the external device (for example, the OLT device). It is possible to switch the connection and attempt communication recovery. Therefore, it can be said that this is effective for a situation where an abnormality occurs on the optical line and a receiving device (for example, an ONU device) connected to an external device cannot communicate normally.

  Note that at least an optical line redundancy system and an optical line distribution device as described below are also disclosed in any of the embodiments described above.

(1) Connected to a plurality of input lines (for example, optical cables 1-1 and 1-2) to which an optical signal is input, and from one input line (for example, optical cable 1-1) selected from the input lines A plurality of optical signal distribution devices (for example, optical switch built-in coupler 2) that distribute and transmit input optical signals to a plurality of output lines (for example, optical cables 7-1 to 7-n) are provided. A device selects a single input line from a plurality of input lines to which an optical signal is input (for example, optical switch 3), and receives an optical signal input from the input line selected by the switch. When there is an abnormality in the received light power of the optical signal and the received light power of the optical signal (for example, when the received light power fluctuates or the received light power is less than the threshold value), Switch switching means (for example, the light reception monitoring unit 4) for switching the input line to be selected, and optical signal distribution means (for example, optical signal distribution means for distributing the optical signal received from the input line via the switch to a plurality of output lines) And an optical coupler unit 6), and one input line in each optical signal distribution device is connected to one output line in another optical signal distribution device, and one output line in each optical signal distribution device is the other An optical line redundancy system connected to one input line in the optical signal distribution apparatus of the present invention.

(2) An optical line redundancy system in which the switch switching means switches the input line to be selected by the switch when the received light power monitoring means detects the fluctuation of the optical signal.

(3) An optical line redundancy system in which the switch switching means switches the input line to be selected by the switch when the received light power monitoring means detects an optical signal having a received light power that falls below a predetermined threshold.

(4) The switch switching means is connected to one of the plurality of output lines distributed by the optical signal distribution means (for example, the optical cable 7-n), and the light receiving power of the optical signal received via the line is set. An optical line redundancy system that switches the input line to be selected by the switch when there is an abnormality.

(5) An optical line redundancy system in which the optical signal distribution means is an optical coupler, and the optical coupler and the switch are included in one device (for example, the optical switch built-in coupler 2).

(6) Connected to a plurality of input lines (for example, optical cables 1-1 and 1-2) to which an optical signal is input, and from one input line (for example, optical cable 1-1) selected from the input lines An optical signal distribution device (for example, optical switch built-in coupler 2) that distributes an input optical signal to a plurality of output lines (for example, optical cables 7-1 to 7-n) and transmits the optical signal. A switch (for example, optical switch 3) for selecting any one of the input lines to be received, and a received light power monitor for monitoring the received light power of an optical signal input from the input line selected by the switch Means (for example, light reception monitoring unit 4) and an input line to be selected for the switch when there is an abnormality in the light reception power of the optical signal (for example, when the light reception power fluctuates or the light reception power is less than the threshold) A switch switching unit (for example, a light reception monitoring unit 4) for switching, and an optical signal distribution unit (for example, an optical coupler unit 6) that distributes and transmits an optical signal received from an input line via a switch to a plurality of output lines. One input line in the optical signal distribution device itself is connected to one output line in the other optical signal distribution device, and one output line in the optical signal distribution device itself is connected to one in the other optical signal distribution device. Optical signal distribution device connected to the input line.

(7) An optical signal distribution device in which the switch switching unit switches the input line to be selected by the switch when the received light power monitoring unit detects fluctuation of the optical signal.

  The present invention is suitably applied to an optical signal redundancy system that makes an optical line redundant.

1-1,1-2,5,7-1 to 7-n Optical cable 2,26,36,41,51,67,69-71,87-90 Coupler with built-in optical switch 3,25,35,40,53 , 68 Optical switch 4, 27, 37, 42, 54 Light reception monitoring unit 6, 28, 38, 43, 56 Optical coupler unit 20, 30, 60, 80 OLT device 22, 32 Two-branch optical coupler 29, 39, 44, 82 ONU device 62 4-branch optical coupler 91-96 Backup trunk route

Claims (9)

  1. A plurality of optical signal distribution devices that are connected to a plurality of input lines to which optical signals are input and that distribute and transmit an optical signal input from one input line selected from the input lines to a plurality of output lines Prepared,
    Each of the optical signal distribution devices,
    A switch that selects any one of the plurality of input lines to which the optical signal is input; and
    A received light power monitoring means for monitoring a received light power of an optical signal input from an input line selected by the switch;
    When there is an abnormality in the light receiving power of the optical signal, switch switching means for switching the input line to be selected by the switch,
    An optical signal distribution means for distributing and transmitting an optical signal received from an input line via the switch to a plurality of output lines;
    One input line in each optical signal distribution device is connected to one output line in another optical signal distribution device, and one output line in each optical signal distribution device is one input in the other optical signal distribution device. An optical signal redundancy system characterized by being connected to a line.
  2. The optical signal redundancy system according to claim 1, wherein the switch switching unit causes the switch to switch the input line to be selected when the received light power monitoring unit detects fluctuation of the optical signal .
  3. 3. The optical signal redundancy system according to claim 1, wherein the switch switching unit switches the input line to be selected by the switch when the received light power monitoring unit detects an optical signal whose received light power falls below a predetermined threshold value. 4. .
  4. The switch switching means is connected to one of the output lines distributed by each optical signal distribution means, and is selected as the switch when there is an abnormality in the light receiving power of the optical signal received through the line. The optical signal redundancy system according to claim 1, wherein an input line to be switched is switched.
  5. The optical signal distribution means is an optical coupler,
    The optical signal redundancy system according to any one of claims 1 to 4, wherein the optical coupler and the switch are included in one device.
  6. An optical signal distribution device that is connected to a plurality of input lines to which optical signals are input and distributes and transmits an optical signal input from one input line selected from the input lines to a plurality of output lines. And
    A switch that selects any one of the plurality of input lines to which the optical signal is input; and
    A received light power monitoring means for monitoring a received light power of an optical signal input from an input line selected by the switch;
    When there is an abnormality in the light receiving power of the optical signal, switch switching means for switching the input line to be selected by the switch,
    An optical signal distribution means for distributing and transmitting an optical signal received from an input line via the switch to a plurality of output lines;
    One input line in the optical signal distribution device itself is connected to one output line in the other optical signal distribution device, and one output line in the optical signal distribution device itself is connected to one output line in the other optical signal distribution device. An optical signal distribution device characterized by being connected to an input line.
  7. The optical signal distribution device according to claim 6, wherein the switch switching unit switches the input line to be selected by the switch when the received light power monitoring unit detects fluctuation of the optical signal .
  8. A plurality of optical signal distribution devices connected to a plurality of input lines to which an optical signal is input, and distributing and transmitting an optical signal input from one input line selected from the input lines to a plurality of output lines An optical line redundancy method using
    One input line in each optical signal distribution device is connected to one output line in another optical signal distribution device, and one output line in each optical signal distribution device is one input in the other optical signal distribution device. Connected to the line,
    Each optical signal distribution device monitors the received light power of the optical signal input from the selected input line,
    When each optical signal distribution device has an abnormality in the light receiving power of the optical signal input from the input line, the input line is switched to the switch that selects the connection destination of the input line,
    Each of the optical signal distribution devices distributes an optical signal received from an input line via the switch to a plurality of output lines and transmits the optical signal .
  9. The optical signal redundancy method according to claim 8, wherein each optical signal distribution device causes the switch to switch the input line when detecting a fluctuation of the optical signal input from the selected input line.
JP2010058003A 2010-03-15 2010-03-15 Optical signal redundancy system, optical signal distribution device, and optical signal redundancy method Active JP5196595B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2010058003A JP5196595B2 (en) 2010-03-15 2010-03-15 Optical signal redundancy system, optical signal distribution device, and optical signal redundancy method

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2010058003A JP5196595B2 (en) 2010-03-15 2010-03-15 Optical signal redundancy system, optical signal distribution device, and optical signal redundancy method

Publications (2)

Publication Number Publication Date
JP2011193263A JP2011193263A (en) 2011-09-29
JP5196595B2 true JP5196595B2 (en) 2013-05-15

Family

ID=44797730

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2010058003A Active JP5196595B2 (en) 2010-03-15 2010-03-15 Optical signal redundancy system, optical signal distribution device, and optical signal redundancy method

Country Status (1)

Country Link
JP (1) JP5196595B2 (en)

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6103033A (en) 1998-03-04 2000-08-15 Therasense, Inc. Process for producing an electrochemical biosensor
US6120676A (en) 1997-02-06 2000-09-19 Therasense, Inc. Method of using a small volume in vitro analyte sensor
US6134461A (en) 1998-03-04 2000-10-17 E. Heller & Company Electrochemical analyte
US6162611A (en) 1993-12-02 2000-12-19 E. Heller & Company Subcutaneous glucose electrode
US6175752B1 (en) 1998-04-30 2001-01-16 Therasense, Inc. Analyte monitoring device and methods of use
US6251260B1 (en) 1998-08-24 2001-06-26 Therasense, Inc. Potentiometric sensors for analytic determination
US6299757B1 (en) 1998-10-08 2001-10-09 Therasense, Inc. Small volume in vitro analyte sensor with diffusible or non-leachable redox mediator
US6591125B1 (en) 2000-06-27 2003-07-08 Therasense, Inc. Small volume in vitro analyte sensor with diffusible or non-leachable redox mediator
US6616819B1 (en) 1999-11-04 2003-09-09 Therasense, Inc. Small volume in vitro analyte sensor and methods
US6654625B1 (en) 1999-06-18 2003-11-25 Therasense, Inc. Mass transport limited in vivo analyte sensor
US8287454B2 (en) 1998-04-30 2012-10-16 Abbott Diabetes Care Inc. Analyte monitoring device and methods of use

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP6292984B2 (en) * 2014-06-05 2018-03-14 日本電信電話株式会社 Optical communication line switching apparatus and method

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4728697B2 (en) * 2005-05-17 2011-07-20 日本電気株式会社 Optical switch device and optical access network method and optical access network system using the same
JP4911366B2 (en) * 2008-01-11 2012-04-04 住友電気工業株式会社 PON system and station side device

Cited By (27)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6514718B2 (en) 1991-03-04 2003-02-04 Therasense, Inc. Subcutaneous glucose electrode
US6284478B1 (en) 1993-12-02 2001-09-04 E. Heller & Company Subcutaneous glucose electrode
US6329161B1 (en) 1993-12-02 2001-12-11 Therasense, Inc. Subcutaneous glucose electrode
US6162611A (en) 1993-12-02 2000-12-19 E. Heller & Company Subcutaneous glucose electrode
US6551494B1 (en) 1997-02-06 2003-04-22 Therasense, Inc. Small volume in vitro analyte sensor
US6576101B1 (en) 1997-02-06 2003-06-10 Therasense, Inc. Small volume in vitro analyte sensor
US6120676A (en) 1997-02-06 2000-09-19 Therasense, Inc. Method of using a small volume in vitro analyte sensor
US6143164A (en) 1997-02-06 2000-11-07 E. Heller & Company Small volume in vitro analyte sensor
US6484046B1 (en) 1998-03-04 2002-11-19 Therasense, Inc. Electrochemical analyte sensor
US6134461A (en) 1998-03-04 2000-10-17 E. Heller & Company Electrochemical analyte
US6103033A (en) 1998-03-04 2000-08-15 Therasense, Inc. Process for producing an electrochemical biosensor
US9326714B2 (en) 1998-04-30 2016-05-03 Abbott Diabetes Care Inc. Analyte monitoring device and methods of use
US8226557B2 (en) 1998-04-30 2012-07-24 Abbott Diabetes Care Inc. Analyte monitoring device and methods of use
US8226558B2 (en) 1998-04-30 2012-07-24 Abbott Diabetes Care Inc. Analyte monitoring device and methods of use
US6565509B1 (en) 1998-04-30 2003-05-20 Therasense, Inc. Analyte monitoring device and methods of use
US6175752B1 (en) 1998-04-30 2001-01-16 Therasense, Inc. Analyte monitoring device and methods of use
US8287454B2 (en) 1998-04-30 2012-10-16 Abbott Diabetes Care Inc. Analyte monitoring device and methods of use
US6251260B1 (en) 1998-08-24 2001-06-26 Therasense, Inc. Potentiometric sensors for analytic determination
US6461496B1 (en) 1998-10-08 2002-10-08 Therasense, Inc. Small volume in vitro analyte sensor with diffusible or non-leachable redox mediator
US6592745B1 (en) 1998-10-08 2003-07-15 Therasense, Inc. Method of using a small volume in vitro analyte sensor with diffusible or non-leachable redox mediator
US6618934B1 (en) 1998-10-08 2003-09-16 Therasense, Inc. Method of manufacturing small volume in vitro analyte sensor
US6299757B1 (en) 1998-10-08 2001-10-09 Therasense, Inc. Small volume in vitro analyte sensor with diffusible or non-leachable redox mediator
US6338790B1 (en) 1998-10-08 2002-01-15 Therasense, Inc. Small volume in vitro analyte sensor with diffusible or non-leachable redox mediator
US6654625B1 (en) 1999-06-18 2003-11-25 Therasense, Inc. Mass transport limited in vivo analyte sensor
US6749740B2 (en) 1999-11-04 2004-06-15 Therasense, Inc. Small volume in vitro analyte sensor and methods
US6616819B1 (en) 1999-11-04 2003-09-09 Therasense, Inc. Small volume in vitro analyte sensor and methods
US6591125B1 (en) 2000-06-27 2003-07-08 Therasense, Inc. Small volume in vitro analyte sensor with diffusible or non-leachable redox mediator

Also Published As

Publication number Publication date
JP2011193263A (en) 2011-09-29

Similar Documents

Publication Publication Date Title
US7233738B2 (en) Protection switching architecture and method of use
US5216666A (en) 1:n ring-type signal protection apparatus
US6081359A (en) Transmitting apparatus and receiving apparatus for wavelength-division-multiplex signal transmission
US5870212A (en) Self-healing optical network
US5867289A (en) Fault detection for all-optical add-drop multiplexer
US7643751B2 (en) Network managing apparatus, optical add/drop multiplexer, and network managing method
US7406029B1 (en) Fault tolerant optical data communication network having auto discovery
KR100547808B1 (en) Frame structure for redundancy apparatus and method and the control of the Gigabit Ethernet Passive Optical Network
US7340170B2 (en) Wavelength-division multiplexed self-healing passive optical network
JP3441671B2 (en) Optical ring network recovery method and system
US6616349B1 (en) Two-fiber interconnected ring architecture
JP2784080B2 (en) Node for use in a ring network and its failure recovery method and ring network
EP0851614A1 (en) Method and arrangement for detecting faults in a network
US20070292129A1 (en) Method and Node Apparatus for Traffic Protection in Optical Transport Network
US6327400B1 (en) Protection scheme for single fiber bidirectional passive optical point-to-multipoint network architectures
KR100610245B1 (en) Communication recovering system for wavelength division multiplexed passive optical network
US7046929B1 (en) Fault detection and isolation in an optical network
US7212541B2 (en) Wavelength division multiplexed (WDM) ring passive optical network (PON) with route protection for replacement of splitter based passive optical networks
US7764881B2 (en) Optical apparatus and optical cross connect apparatus
US7352966B2 (en) Method and apparatus for capacity-efficient restoration in an optical communication system
CN1222821C (en) Optical channel protector and method based on WDM layer
JP4593267B2 (en) Optical node and the optical add drop apparatus
JPH06169302A (en) High-speed facility protection for digital remote communication system
US5757526A (en) Optical communication network and method for optically detecting a fault
US20040105136A1 (en) Interconnections and protection between optical communications networks

Legal Events

Date Code Title Description
A977 Report on retrieval

Free format text: JAPANESE INTERMEDIATE CODE: A971007

Effective date: 20120704

A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20120710

A521 Written amendment

Free format text: JAPANESE INTERMEDIATE CODE: A523

Effective date: 20120905

TRDD Decision of grant or rejection written
A01 Written decision to grant a patent or to grant a registration (utility model)

Free format text: JAPANESE INTERMEDIATE CODE: A01

Effective date: 20130108

A61 First payment of annual fees (during grant procedure)

Free format text: JAPANESE INTERMEDIATE CODE: A61

Effective date: 20130201

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20160215

Year of fee payment: 3

R150 Certificate of patent or registration of utility model

Free format text: JAPANESE INTERMEDIATE CODE: R150

S111 Request for change of ownership or part of ownership

Free format text: JAPANESE INTERMEDIATE CODE: R313111

R350 Written notification of registration of transfer

Free format text: JAPANESE INTERMEDIATE CODE: R350