JP4842230B2 - Access system and channel allocation method - Google Patents

Description

  The present invention relates to a system that transmits a main signal and a service signal separate from the main signal from a station-side device to a user home device.

  This service signal needs to be transmitted for each user according to the individual needs of the user. Furthermore, service signals for a plurality of different services may be transmitted to one user.

  Time delay of VoIP technology (IP telephone) by frequency-multiplexing a subcarrier signal modulated by PCM (Pulse Code Modulation) with a subcarrier and a serial signal of 8B / 10B encoded Gigabit Ethernet (registered trademark) There is already a technique (see, for example, Patent Document 1) that solves the signal quality problem that places importance on real-time performance and uses it in an access network.

Also, in recent years, as an access network configuration to realize FTTH (Fiber To The Home), it is the point-to-multipoint system (P2MP) shown in FIG. 1 and accommodates multiple users economically by using an optical splitter as a passive element. PON (Passive
Optical Network) system exists.

As shown in FIG. 1, a station side device (hereinafter referred to as OLT (Optical Line
Signals # 1 to #N addressed to all user premises equipment are transmitted to each user premises equipment (hereinafter referred to as ONU (Optical Network Unit)). . Each ONU # 1 to #N extracts only a signal addressed to itself from the received signals.

Above all, GE-PON (Gigabit which applied gigabit Ethernet technology)
The Ethernet Passive Optical Network) system is currently widely used as a high-speed and economical access network configuration.

Patent No. 3795371

  However, in such a P2MP access network, a signal different from the main signal on the station side (hereinafter referred to as a service signal: a signal different from the main signal given a packetized user identifier) is used. When a large number are prepared and multiplexed, signals are basically transmitted in a broadcast type, so it is impossible to individually transmit each service signal for each user.

  In addition, in a point-to-point (P2P, or single star: SS system) access network, it is not necessary to provide services for each user. It is necessary to identify

  The present invention has been made in order to solve such problems, and an access system and a channel allocation method capable of individually transmitting a service signal for each user or for each service in a broadcast communication form The purpose is to provide.

  In the present invention, in downlink communication of an access system such as GE-PON, for example, a plurality of service signals (voice such as radio, character information such as breaking news) are multiplexed on a plurality of channels in a normal main signal, A signal is transmitted for each of a plurality of ONUs connected to the OLT, and a service signal can be individually supplied to each ONU. At this time, channel assignment is performed before providing the service.

  According to the present invention, by performing channel allocation before providing a service, the service signal can be individually distributed for each user or for each service, although it is a broadcast communication mode.

  In other words, the present invention is an access system that performs communication between the OLT and the ONU, and the feature of the present invention is that each of a plurality of service signals that are different from the main signal in the downstream signal from the OLT to the ONU. Means for performing channel assignment setting before service provision and means for multiplexing a plurality of service signals into a main signal using a plurality of channels are provided.

  According to this, it is possible to multiplex an individual service signal into a main signal for each user or for each service and transmit it to the user while being in a broadcast type communication form. On the user side, since the channel assignment setting is completed before the service is provided, only the service signal of the channel assigned to the user can be received.

  The means for performing channel assignment setting may comprise means for performing fixed channel assignment. Alternatively, the means for performing channel assignment setting may comprise means for dynamically performing channel assignment.

  For example, a plurality of channels can be assigned to each ONU. Alternatively, multiple channels can be assigned to each service. Alternatively, a plurality of channels can be assigned to each ONU.

The means for fixedly assigning the channel is, for example, LLID (Logical Link
Means for assigning a channel corresponding to (ID). In addition, when a new ONU is connected to the OLT, it is desirable to provide means for the OLT to determine a channel corresponding to the LLID newly assigned to the ONU using the Register frame or the OAM frame and notify the ONU. .

  Further, the OLT can be provided with means for sequentially monitoring the connection status or operation status of the ONU using the Register frame or the OAM frame, and sequentially updating the allocation of the channel corresponding to the LLID according to the change of the status of the ONU. .

  According to this, since the channel allocation corresponding to the LLID of the ONU that has been released from connection or the dormant ONU can be omitted, the channel utilization efficiency can be improved.

  The present invention can also be viewed from the viewpoint of a channel allocation method in an access system that performs communication between the ONU and the OLT. That is, according to the present invention, channel assignment is set before providing a service for each of a plurality of service signals different from the main signal in the downlink signal from the OLT to the ONU, and the plurality of service signals are transmitted to the main signal using a plurality of channels. The channel allocation method is characterized in that the channel allocation method is multiplexed.

  The present invention can also be viewed from the viewpoint of a power failure receiving device. That is, the present invention is provided in the ONU of the access system of the present invention, and after the optical signal arriving at the ONU from the OLT is converted into an electric signal, the electric signal is branched from the ONU, and the branch is made by the branching means. And a filter means that is driven by the electric power of the generated electric signal and extracts a frequency component corresponding to a pre-assigned channel from the electric signal.

  Alternatively, the present invention is provided in the ONU of the access system of the present invention, and extracts from the optical signal arriving at the ONU from the OLT, an optical signal having a wavelength corresponding to a pre-assigned channel, and the extraction means extracts the optical signal. And a means for converting an optical signal into an electrical signal.

  As described above, if the ONU side controls the channel assigned in advance by the channel allocation method of the present invention, it is not necessary to identify the signal addressed to itself on the ONU side. Since it is not necessary to perform complicated arithmetic processing, a power source for operating the processor or the like is unnecessary, and an ONU that can receive a signal from the OLT even during a power failure can be realized.

  According to the present invention, the service signal can be individually distributed for each user or for each service, although it is a broadcast type communication form. As a result, once the ONU side controls the pre-assigned channel, it is not necessary to identify the signal addressed to itself on the ONU side, so there is no need to perform complicated arithmetic processing associated with reception processing on the ONU side. An access system can be realized.

  An embodiment of the present invention will be described with reference to FIGS. 2 and 3 are diagrams showing the concept of user multiplexing and service multiplexing, FIG. 2 is an example of frequency multiplexing f1 to fN, and FIG. 3 is an example of wavelength multiplexing λ1 to λN. In the case of the frequency multiplexing shown in FIG. 2, frequency multiplexing is performed at the time of an electrical signal, and then the optical signal is converted and transmitted from the OLT to the ONU. In the case of the wavelength multiplexing shown in FIG. 3, wavelength multiplexing is performed with the optical signal and transmitted from the OLT to the ONU. In the following description, GE-PON is taken as an example.

  Here, the user multiplexing means that service signals are individually transmitted from the OLT to each ONU in GE-PON downlink signal communication in which a plurality of service signals are multiplexed. In the broadcast type GE-PON downlink signal communication, GE-PON signals and service signals for all users (maximum 32) are transmitted to each user (ONU), but the service signal is sent to each user individually. Is called here for convenience. That is, it means that the channel to be multiplexed is associated with each user.

  Service multiplexing is generally the same as user multiplexing in terms of multiplexing or demultiplexing, but the service signal channel handling is different. In the user multiplexing, a channel is associated with each user, but this indicates that a channel is associated with each service (voice, text, etc.). If the number of usable channels is greater than the number of users (32 or more), user multiplexing and service multiplexing can be performed simultaneously. Alternatively, a plurality of services can be provided to each user. For example, in the case of a radio format, it has a plurality of channels.

  In the case of a P2P system, channel control for user multiplexing is not required, but channel allocation is required for service multiplexing.

  In addition, the fixed assignment means that a channel is fixedly assigned to each ONU by the first exchange between the OLT and the ONU (only once in advance communication). Basically, once it is decided, the channel is fixed.

  Also, dynamic allocation is different from fixed allocation in that the allocation channel of each ONU is changed over time. Due to the nature of GE-PON, ONUs under the OLT are not always connected and communicating, and it is economical to assign a fixed channel to them because of frequency utilization efficiency and wavelength utilization efficiency. is not. In addition, by being able to change sequentially, it becomes possible to provide a selective service by OLT. Thereby, each ONU can be differentiated and services can be diversified.

  In addition, services that can be dynamically allocated can provide various services. If the allocation is fixed, the channels after the allocation are allocated once fixed and are used, for example, when the service is not required. It becomes possible to provide a more flexible service such as disabling a channel once allocated or not allocating a channel to a user who does not need it from the beginning.

  Dynamic channel allocation setting and multi-channel allocation setting for one user are possible (depending on how many ONUs are connected to one OLT and how many ONUs are used in time) Further, it is possible to assign a plurality of channels (N × Mi: N is the number of users, and Mi is the number of channels for each user (i = 1 to N)) with a weight assigned to each user.

  Next, a system configuration example of the signal multiplexing method will be described.

SCM (Sub-Carrier Multiplexing): Carrier Division Multiplexing FIG. 4 is a schematic diagram. In the service signal multiplexing unit 10 of the OLT, frequency multiplexing is performed on the normal main signal of P2MP using an adder or a multiplier.

  In FIG. 4, for ease of explanation, the ONU # 1 is illustrated as having a power failure receiver 40 connected as an external device, but the power failure receiver 40 is an internal function of the ONU # 1. Good. The operation of the ONU including the ONU circuit 50 is the same as that of the prior art except that the ONU side does not need to identify the signal addressed to itself if the ONU side controls the channels allocated in advance. Description is omitted.

  The power failure receiver 40 has a filter configuration that demultiplexes the received frequency multiplexed signal into a service signal and a main signal. After ONU # 1 receives and multiplex-converts the frequency multiplexed signal, the service signal is extracted by the variable bandpass filter 12 in which the frequency is set in advance by the channel setting method performed by the receiver 40 at the time of power failure during normal communication described later. Each service is provided by output means corresponding to the service signal (speaker for voice, display for character information, sensor for sensor network signal, etc.).

  For an ONU that does not receive a service signal, the subcarrier signal to be multiplexed can be a noise component with respect to the main signal, so signal degradation is avoided by passing through a high-pass filter or a low-pass filter. In addition, when the subcarrier signal strength is sufficiently weaker than the main signal strength, there is a method of transmitting the signal as it is without adding a new filter. In this case, a plurality of subcarriers are used for each channel.

  In the case of GE-PON, a plurality of subcarrier frequencies for modulating a service signal have an influence on an 8B / 10B encoded GE-PON signal in a low frequency band of 15 MHz or less or a high frequency band of 1.25 GHz or more. There are few frequency bands.

  Further, by using an element that operates only with the energy of the optical signal transmitted from the OLT and converts the optical signal into an electrical signal in the photoelectric conversion unit 30 provided in the ONU # 1, the ONU side can be operated during a power failure. Even if there is, it is possible to convert an optical signal into an electrical signal, and the power receiving device 40 at the time of a power failure branches an electrical signal output from the photoelectric conversion unit 30 and operates with only the electric power of this electrical signal. The service signal can be extracted using the filter 12. Furthermore, by using a speaker or a display that operates only with electric power of an electric signal converted from an optical signal, a signal transmitted from the OLT can be output on the ONU side even during a power failure. The transmission band of the variable bandpass filter 12 is set by the ONU # 1 during normal times (when energized) other than during a power failure.

  The point to be noted here is that if the ONU side controls the channel allocated in advance by the channel allocation method of the present invention, it is not necessary to identify the signal addressed to itself on the ONU side. There is no need to perform complicated arithmetic processing associated with reception processing.

  As in the prior art, in order to identify a signal addressed to itself after receiving a signal from the OLT, arithmetic processing using a processor or the like is required, and a power source for operating the processor or the like is required. If the processing is simply to transmit a signal in a preset transmission band by the variable bandpass filter 12, it is possible to realize the power failure receiver 40 that can receive the signal from the OLT even during a power failure.

WDM (Wavelength Division Multiplexing): Wavelength Division Multiplexing FIG. 5 is a schematic diagram. The service signal multiplexing unit 20 of the OLT multiplexes service signals in a wavelength band different from the downlink main signal using a multi-wavelength light source, a plurality of LDs (corresponding to the number of channels), and the like. Also, when another wavelength is used for the uplink, a wavelength band different from the uplink wavelength is used.

  In FIG. 5, for ease of explanation, the ONU # 1 is illustrated as having a power failure receiving device 41 connected as an external device, but the power failure receiving device 41 may be an internal function of the ONU # 1. Good. Note that the ONU operation is the same as that of the prior art except that the ONU side does not need to identify the signal addressed to itself if the ONU side controls the channels assigned in advance.

  The power receiving apparatus 41 at the time of a power failure extracts a service signal by a variable WDM (wavelength) filter 22 set in advance using a setting method described later that is performed during normal communication, and each service is provided by an output unit corresponding to the signal. Is done. In this case, each wavelength light different from the main signal becomes a channel.

  In the case of GE-PON, since the downstream wavelength of the main signal is 1.49 nm and the upstream wavelength is 1.31 nm, the service signal is multiplexed in a wavelength band that does not affect the wavelength.

  In addition, when the ONU for GE-PON has a WDM filter, the wavelength other than the GE-PON downlink signal is removed. In this case, special processing is performed for the ONU that does not receive the service signal. There is no need to do it.

  That is, channel allocation is nothing but setting the frequency or wavelength of a variable filter for extracting a service signal by the ONU, regardless of whether the signal multiplexing method is SCM or WDM.

  In addition, by using an element that operates only by the energy of the optical signal transmitted from the OLT and converts the optical signal into an electrical signal in the photoelectric conversion unit 31 provided in the power failure receiving device 41, the ONU side can perform the power failure. Even at times, optical signals can be converted into electrical signals. Furthermore, by using a speaker or display that operates only with the power of the electrical signals converted from the optical signals, it is transmitted from the OLT even during power outages. Can be output on the ONU side. The transmission wavelength of the variable WDM filter 22 is set by the ONU # 1 during normal times (when energized) other than during a power failure.

  As described above, the point to be noted here is that if the ONU side controls the channel allocated in advance by the channel allocation method of the present invention, it is not necessary to identify the signal addressed to itself on the ONU side thereafter. Therefore, there is no need to perform complicated arithmetic processing associated with reception processing on the ONU side.

  In addition, it is obvious that the receivers 40 and 41 during a power failure operate even during normal times (when energized) other than during a power failure, and can be used even during normal times.

(First Embodiment: Method Using Fixed Allocation User Multiplex LLID)
In GE-PON, the MAC frame, which is the basic structure of the main signal, is transmitted to each ONU for all users. Each ONU itself is transmitted by the LLID (Logical Link ID) included in the preamble of the frame. Only the frames transmitted to are fetched, and the other frames are discarded.

  Here, a method of associating the LLID itself with a channel was considered. As shown in FIG. 6, in this method, it is assumed that the LLID assigned to each ONU by the OLT is fixed (32 because there is a maximum of 32 branches. If the ONU is disconnected or cut off halfway, it is reassigned in the order of reconnection. Example: 0001-0032 etc.). Also in the current GE-PON system, when the OLT assigns an LLID to each ONU in a Discovery process (see below) which is a new ONU registration process, each ONU simultaneously confirms its own LLID value. Therefore, the confirmed ONU uses the LLID value for channel control. In this way, user multiplexing is possible. That is, it is assumed that the OLT and each ONU have a channel table corresponding to the LLID in advance.

(Second Embodiment: Method Using Fixed Allocation User Multiple Register Frame)
In GE-PON, when a new ONU is added under the OLT, the channel assignment unit 11 or 21 performs a Discovery process shown in FIG. 7 in order to perform registration. In the Discovery process, an LLID for identifying each ONU is given by a Register frame transmitted from the OLT. Therefore, control information for controlling which channel each ONU acquires is added to the empty area (PAD) of the Register frame shown in FIG.

  The ONU that has received the control information from the frame (Register frame) included in the GE-PON signal uses the information for filter setting and sets it according to the control information.

  When the ONU is connected and operating, the LLID does not change. In addition, the Discovery process itself is not newly performed except when it is reconnected. Therefore, the channel from which each ONU is obtained by this method is fixed.

(Third Embodiment: Method Using Fixed Allocation User Multiplexed OAM Frame)
OAM (Operation) used for maintenance management of GE-PON
(Administration and Maintenance) frame can be freely set by each carrier or vendor that operates, in comparison with the above-mentioned method of allocating channels only at the time of registration in association with LLID and channel allocation using a Register frame, Has the advantage of being more freely configurable. In addition, the OAM process can be implemented by software, and has the advantage that introduction is easier than the above-described method.

  Here, as shown in FIG. 9, a new OAM frame and an OAM process are set, in which the channel allocation unit 11 or 21 sends a channel control information to each ONU and returns to the OLT that the setting has been completed. To do.

(Fourth Embodiment: Method Using Fixed Allocation Service Multiplex LLID)
In the first embodiment, the target of the channel control information corresponding to the LLID is each user, but service multiplexing can be realized by changing the target of the allocation control information from each user to each service.

  As an example of service multiplexing on the PON, as shown in FIG. 10, when an audio radio is taken as an example, each channel matches the service content. Further, in this case, since all services are transmitted to all users, a user side whose channel contents are known selects a channel and a desired service is provided.

(Fifth Embodiment: Method Using Fixed Assignment Service Multiple Register Frame)
In the second embodiment, the target of the channel allocation control information to be given to the free space of the Register frame is each user. However, by changing the target of the allocation control information from each user to each service, service multiplexing can be performed. realizable.

(Sixth Embodiment: Method Using Fixed Allocation Service Multiple OAM Frame)
In the third embodiment, the target of channel allocation control information is each user, but service multiplexing can be realized by changing the target of allocation control information from each user to each service.

(Seventh Embodiment: Method Using Fixed Multiple Allocation User Multiplex & Service Multiplex LLID)
(1) Allocation of multiple LLIDs The current LLID has a large margin of 2 bytes = 16 bits (65536 ways), and it is also possible to allocate multiple LLIDs to each ONU using an unused area. . Therefore, as shown in a schematic diagram in FIG. 11, by assigning a plurality of LLIDs assigned in the first embodiment to each ONU, each ONU can have a plurality of channels, and a service is provided for each channel. User multiplexing and service multiplexing are performed simultaneously.

(Eighth Embodiment: Method Using Fixed Multiple Allocation User Multiplex & Service Multiplex LLID)
(2) Multiple allocation of LLID (parent-child LLID)
By assigning a plurality of LLIDs to each ONU, a flexible system that simultaneously performs user multiplexing and service multiplexing can be configured. Here, a single LLID assigned in the first embodiment is set as a parent LLID for realizing user multiplexing and a child LLID corresponding to each service, and a plurality of child LLIDs are fixed to the parent LLID. The OLT and each ONU have the fixed set as a table in advance, and user multiplexing and service multiplexing are performed simultaneously.

  In this case, there are only 32 sets of parent-child LLIDs. The number of children depends on how many services you want to provide. As an image, user multiplexing is performed with the parent LLID, and service multiplexing is performed with the child LLID.

  FIG. 12 shows a schematic diagram. Compared to the seventh embodiment, there is an advantage that the control on the OLT side is simple (because the table is unique and fixed, and it is not necessary for the OLT to perform channel control for service multiplexing).

(Ninth Embodiment: Method Using Fixed Multiple Allocation User Multiplex & Service Multiple Register Frame)
In the second embodiment, a single channel allocation control information is assigned to the free area of the Register frame. However, the allocation control information to be assigned is changed to one for setting a plurality of channels, and a plurality of channels are assigned to each ONU. By performing the setting, user multiplexing and service multiplexing are realized.

(Tenth Embodiment: Method Using Fixed Multiple Allocation User Multiplex & Service Multiple OAM Frame)
In the third embodiment, the allocation control of each user is performed using the OAM frame. However, by including not only each user but also each service, the target of channel allocation control information is used to perform user multiplexing and service multiplexing. Realize.

(Eleventh Embodiment: Method Using Dynamically Assigned User Multiplex LLID)
In the first embodiment, the LLID and the channel allocation control information are notified only when a new ONU is registered. However, as shown in FIG. 13, the Discovery process is changed to be performed sequentially to realize dynamic allocation. When this method is used, the LLID is sequentially updated, and the channel of each ONU is dynamically updated accordingly.

  However, the frequency of the Discovery process that is sequentially performed is sufficiently low so that increasing the number of processes does not affect the band of the main signal more than necessary.

(Twelfth Embodiment: Method Using Dynamically Assigned User Multiple Register Frame)
In the second embodiment, a Register frame for notifying LLID is transmitted only when a new ONU is registered. However, as shown in FIG. 13, the Discovery process is changed to be performed sequentially to realize dynamic channel allocation. When this method is used, the LLID is sequentially updated, and accordingly, the exchange of Register frames is also sequentially performed, and the channel of each ONU is dynamically updated.

  It is assumed that the frequency of the Discovery process that is sequentially performed is sufficiently low so that increasing the number of processes does not affect the bandwidth of the GE-PON signal more than necessary.

(Thirteenth Embodiment: Method Using Dynamically Allocated User Multiplexed OAM Frame)
In the third embodiment, channel allocation using the OAM frame and process is performed only once. However, as shown in FIG. 14, channel control information is sent to each ONU, and the completion of setting is returned to the OLT. A new OAM frame and an OAM process having such a process are set and inserted between normal main signal communication frames at a frequency that does not affect the dynamic allocation, thereby realizing dynamic allocation.

(14th Embodiment: Method Using Dynamic Allocation Service Multiplex LLID)
In the eleventh embodiment, the target of the channel control information corresponding to the LLID is assumed to be each user. However, the service control is dynamically changed by changing the target of the allocation control information from each user to each service. it can.
(Fifteenth Embodiment: Method Using Dynamic Assignment Service Multiple Register Frame)
In the twelfth embodiment, the target of channel allocation control information to be assigned to the free space of the Register frame is each user. However, by changing the target of allocation control information from each user to each service, Service multiplexing can be realized.

(Sixteenth Embodiment: Method Using Dynamic Allocation Service Multiple OAM Frame)
In the thirteenth embodiment, the target of the channel allocation control information is each user, but dynamic service multiplexing can be realized by changing the target of the allocation control information from each user to each service.

(Seventeenth Embodiment: Method Using Multiple Allocation User Multiplex & Service Multiplex LLID)
(1) Multiple allocation of LLIDs In the seventh embodiment, fixed user multiplexing and service multiplexing are realized simultaneously by allocating a plurality of LLIDs to each ONU in the Discovery process at the time of new ONU registration. As shown in the eleventh embodiment, user multiplexing and service multiplexing are dynamically realized by sequentially repeating the Discovery process.

(Eighteenth Embodiment: Method Using Dynamic Multiple Allocation User Multiplex & Service Multiplex LLID)
(2) Multiple allocation of LLID (parent-child LLID)
In the eighth embodiment, parent-child LLID is set and fixed user multiplexing and service multiplexing are realized at the same time in the Discovery process at the time of new ONU registration, but as shown in the eleventh embodiment, Discovery is performed. By repeating the process sequentially, user multiplexing and service multiplexing are realized dynamically.
(Nineteenth Embodiment: Method Using Dynamic Multiple Allocation User Multiplex & Service Multiple Register Frame)
In the ninth embodiment, fixed user multiplexing and service multiplexing are realized simultaneously by assigning multiple channel allocation information to the free area of the Register frame in the Discovery process at the time of new ONU registration. As shown in the above embodiment, user multiplexing and service multiplexing are dynamically realized by sequentially repeating the Discovery process.

(20th Embodiment: Method Using Multiple Allocation User Multiplex & Service Multiple OAM Frame)
In the tenth embodiment, fixed user multiplexing and service multiplexing are realized at the same time by providing channel allocation control information for each user and each service, but as shown in the thirteenth embodiment. In addition, user multiplexing and service multiplexing are dynamically realized by sequentially repeating exchange of OAM frames.

  According to the present invention, since the service signal can be individually distributed for each user or for each service, it can be used for improving service quality, for example, in GE-PON.

  Furthermore, if the ONU side controls the channels assigned in advance, there is no need to identify the signal addressed to itself on the ONU side, so there is no need to perform complicated arithmetic processing associated with reception processing on the ONU side. For example, as shown in FIG. 4 or FIG. 5, the present invention can be used to realize an access system that can receive a signal from the OLT even when the ONU side is in the event of a power failure.

The conceptual diagram of the optical access system of a prior art. The conceptual diagram in the frequency domain of the channel allocation of user multiplexing and service multiplexing defined in the present invention. The conceptual diagram in the wavelength domain of the channel allocation of user multiplexing and service multiplexing defined by this invention. The conceptual diagram of the system configuration example of the SCM system of the signal multiplexing system example in this invention. The conceptual diagram of the system configuration example of the WDM system of the signal multiplexing system example in this invention. The conceptual diagram of 1st embodiment of the channel allocation of this invention. The conceptual diagram of 2nd embodiment of the channel allocation of this invention. The conceptual diagram of 2nd embodiment of the channel allocation of this invention. The conceptual diagram of 3rd embodiment of the channel allocation of this invention. The conceptual diagram of the service multiplexing example of 4th embodiment of the channel allocation of this invention. The conceptual diagram of 7th embodiment of the channel allocation of this invention. The conceptual diagram of 8th embodiment of the channel allocation of this invention. The conceptual diagram of the sequential Discovery process in the 11th and 12th embodiment of the channel allocation of this invention. The conceptual diagram of 13th embodiment of the channel allocation of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10, 20 Service signal multiplexing part 11, 21 Channel allocation part 12 Variable band pass filter 22 Variable WDM filter 30, 31 Photoelectric conversion part 40, 41 Power failure receiver 50 ONU circuit

Claims (3)

In an access system in which communication is performed between a station side device and a user home device,
Means for performing channel assignment setting before providing a service for each of a plurality of service signals different from the main signal in the downlink signal from the station side device to the user premises device;
Means for multiplexing a plurality of service signals into a main signal using a plurality of channels ,
The means for performing channel assignment setting performs channel assignment fixedly or dynamically, assigns a plurality of channels to each user premises apparatus, or assigns to each service,
When performing the channel assignment fixedly, assign a channel corresponding to LLID (Logical Link ID),
The station side device
Means that, when a new user premises apparatus is connected, the station side apparatus determines a channel corresponding to the LLID newly assigned to the user premises apparatus using the Register frame or the OAM frame, and notifies the user premises apparatus ,
Means for successively monitoring a connection status or an operating status of a user home device using a Register frame or an OAM frame, and sequentially updating allocation of a channel corresponding to the LLID according to a change in the status of the user home device;
With
Each user home device
Means for branching the electrical signal from the user premises device after the optical signal arriving at the user premises device from the station side device is converted into an electrical signal;
Filter means which is driven by the power of the electric signal branched by the branching means and extracts a frequency component corresponding to a pre-assigned channel from the electric signal;
An access system, characterized in that a power failure receiving device is provided . In an access system in which communication is performed between a station side device and a user home device,
Means for performing channel assignment setting before providing a service for each of a plurality of service signals different from the main signal in the downlink signal from the station side device to the user premises device;
Means for multiplexing a plurality of service signals into a main signal using a plurality of channels;
With
The means for performing channel assignment setting includes means for performing channel assignment fixedly or dynamically, and assigning a plurality of channels to each user premises apparatus or assigning to each service. ,
The means for performing the channel assignment fixedly includes means for assigning a channel corresponding to LLID (Logical Link ID),
The station side device
Means that, when a new user premises apparatus is connected, the station side apparatus determines a channel corresponding to the LLID newly assigned to the user premises apparatus using the Register frame or the OAM frame, and notifies the user premises apparatus ,
Means for successively monitoring a connection status or an operating status of a user home device using a Register frame or an OAM frame, and sequentially updating allocation of a channel corresponding to the LLID according to a change in the status of the user home device;
With
Each user home device
Means for extracting an optical signal having a wavelength corresponding to a pre-assigned channel from an optical signal arriving at a user premises apparatus from a station side device;
Means for converting the optical signal extracted by the extracting means into an electrical signal;
Power outage receiving device equipped with
An access system characterized by that . In a channel allocation method in an access system in which communication is performed between a station side device and a user premises device,
Channel assignment settings are made for each of a plurality of service signals different from the main signal in the downlink signal going from the station side device to the user premises device before providing the service, and the plurality of service signals are multiplexed onto the main signal using a plurality of channels. A channel assignment method ,
When performing the channel allocation setting, the channel allocation is fixedly or dynamically performed, and a plurality of channels are allocated to each user premises apparatus or allocated to each service,
When performing the channel assignment fixedly, assign a channel corresponding to LLID (Logical Link ID),
When a new user premises apparatus is connected to the station side apparatus, the station side apparatus determines a channel corresponding to the LLID newly assigned to the user premises apparatus using the Register frame or the OAM frame, and the user premises apparatus Notify the device, monitor the connection status or operating status of the user premises equipment sequentially using the Register frame or OAM frame, sequentially update the allocation of the channel corresponding to the LLID according to the change of the status of the user premises equipment,
The user premises device converts an optical signal arriving at the user premises device from the station side device into an electric signal to be a power source for the user premises device.
A channel access method characterized by the above.

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