JP6401678B2 - Terminal station apparatus and bandwidth allocation method - Google Patents

Description

  The present invention relates to a terminal station apparatus and a bandwidth allocation method.

  Optical access, represented by FTTH (Fiber To The Home), provides economical services by using a passive optical network (PON) in which a terminal equipment and multiple terminal equipment are connected. Realized. In a passive optical communication network, communication between a terminal device and a terminal device is multiplexed by a time division multiplexing method. On the other hand, communication from a terminal device to a terminal device (hereinafter referred to as “uplink communication”) is realized using a control protocol called MPCP (Multi-Point Control Protocol) (for example, see Non-Patent Document 1). ). The transmission amount and transmission start time in uplink communication of each terminal device are centrally controlled in the terminal device, and the control method dynamically changes the transmission amount and static bandwidth allocation that gives the transmission amount fixedly. It can be roughly divided into dynamic bandwidth allocation. As one of dynamic bandwidth allocation, there is one that achieves high bandwidth utilization efficiency by determining a transmission amount using a request amount from each terminal device (see, for example, Patent Document 1).

  Studies are also being made to apply a passive optical communication network to mobile radio communication service networks (hereinafter referred to as “mobile networks”) represented by LTE (Long Term Evolution) and LTE-advanced to make the network more economical. ing. For example, the function of a conventional radio base station is divided into a base station apparatus unit that performs baseband processing and a radio apparatus unit that performs radio processing. Then, the base station apparatus unit is aggregated in the accommodation station and the radio apparatus unit is extended, and a passive optical communication network is applied to a transmission system between the base station apparatus unit and the radio apparatus unit (for example, Patent Documents). 2). In a mobile network, since retransmission control (HARQ: hybrid automatic repeat request) is performed, requirements for delay time between a base station apparatus unit and a radio apparatus unit are severe. Thus, bandwidth allocation for uplink communication from the terminal device to the terminal device is calculated based on the scheduling information for uplink communication notified from the upper device to the user device via the lower device, and notified (for example, patent) Reference 2). As a result, it is possible to transfer an upstream signal from the lower apparatus to the upper apparatus with a low delay.

Japanese Patent No. 3768421 International Publication No. 2014/077168

"IEEE Std. 802.3-2012", IEEE, 2012

Consider a bandwidth allocation method for a terminal device for transferring uplink communication from a lower level device to a higher level device with low delay in a passive optical communication network system that connects a higher level device and a lower level device. Generally, a terminal device in a passive optical communication network system grants transmission permission for uplink communication based on a transmission request from a terminal device. On the other hand, a method of allocating a fixed band without depending on a transmission request of a terminal device, a method of predicting a transmission request based on a past transmission / reception history, and transmission based on information from a host device as in Patent Document 2 By adopting a method for predicting a request (hereinafter referred to as “mobile DBA”), the terminal device can give a transmission permission in a low time without waiting for a transmission request from the terminal device.
On the other hand, uplink communication from a terminal device to a terminal device is generally controlled according to a time division multiple access (TDMA) standard as described in Non-Patent Document 1. Therefore, when a plurality of terminal devices simultaneously receive uplink data from lower devices, the terminal devices perform transmission standby according to TDMA. This delay caused by waiting for transmission cannot be solved by the above-described method.

  In view of the above circumstances, an object of the present invention is to provide a terminal station device and a bandwidth allocation method that can reduce a transmission standby time when a plurality of terminal devices relay communication by time division multiple access.

  One aspect of the present invention is a terminal device connected to a plurality of terminal devices that transmit received data by time division multiple access, and the data received at a predetermined time for each of the plurality of terminal devices. An allocation amount determination unit that determines a bandwidth amount to be transmitted to the terminal device, and a divided bandwidth amount obtained by dividing the bandwidth amount to at least some of the termination devices, and data received by the termination device at the predetermined time And a bandwidth allocating section that allocates the transmission timing to the terminal device so that the first transmission of the data is before the end of the predetermined time.

  One aspect of the present invention is the terminal device described above, wherein the allocation amount determination unit receives the amount of data received by the terminal device based on information indicating a communication schedule of a device lower than the terminal device. And the bandwidth amount is determined based on the calculated data amount.

  Further, one aspect of the present invention is the above-described terminal device, wherein the band amount is divided so that a bandwidth when the plurality of terminal devices transmit data to the terminal device does not exceed an upper limit bandwidth. An allocation number determining unit that determines the number is further provided.

  One aspect of the present invention is the terminal device described above, wherein a time from the end of the predetermined time until the terminal device finishes transmitting the data received at the predetermined time to the terminal device is predetermined. An allocation number determining unit that determines the number of divisions of the bandwidth so as to be less than the delay time.

  Another aspect of the present invention is a bandwidth allocation method executed by a terminal device connected to a plurality of terminal devices that transmit and receive received data by time division multiple access, and each of the plurality of terminal devices An allocation amount determining step for determining a bandwidth amount for transmitting the data received in a predetermined time to the terminal device, and allocating a divided bandwidth amount obtained by dividing the bandwidth amount to at least some of the termination devices, Bandwidth allocation for allocating the timing at which the apparatus receives the data received at the predetermined time into the divided band amounts and transmits the divided data to the terminal device so that the first transmission of the data is before the end of the predetermined time Steps.

  According to the present invention, it is possible to reduce the transmission standby time when a plurality of terminal devices relay communication by time division multiple access.

1 is a configuration diagram of a communication system according to a first embodiment. It is a functional block diagram of the terminal station apparatus by the embodiment. It is a figure which shows the transmission flow of the uplink data by the embodiment. It is a functional block diagram of the terminal station apparatus by 2nd Embodiment. It is a functional block diagram of the terminal station apparatus by 3rd Embodiment. It is a functional block diagram of the terminal station apparatus by 4th Embodiment. It is a figure which shows the transmission flow of the uplink data when using a prior art.

A first embodiment of the present invention will be described with reference to FIGS.
FIG. 1 is a configuration diagram of a communication system 10 according to the present embodiment. As shown in FIG. 1, the communication system 10 includes a host device 1, a terminal device 2, P units (P is an integer equal to or greater than 1), a terminal device 3, and a P-th lower device 4. . Hereinafter, the P terminal devices 3 are referred to as terminal devices 3-1 to 3-P, respectively, and the P lower devices 4 are referred to as lower devices 4-1 to 4-P, respectively. For example, the communication system 10 is a passive optical network (PON) system, the terminal device 2 is an OLT (Optical Line Terminal), and the termination device 3 is an ONU. (Optical Network Unit: optical subscriber line network device).

  The host device 1 and the terminal device 2 and the terminal device 3 and the lower device 4 are connected on a one-to-one basis. In the drawing, the lower device 4 connected to the terminal device 3-p (p is an integer not smaller than 1 and not larger than P) is defined as a lower device 4-p. The terminal device 2 and the terminal devices 3-1 to 3 -P are one-to-many and are connected by an ODN (Optical Distribution Network) using the optical fiber 6 and the optical splitter 7. That is, the terminal device 2 and the terminal devices 3-1 to 3 -P are connected by distributing a communication signal transmitted through one optical fiber 6 into a plurality of signals by the optical splitter 7. The terminal station device 2 multiplexes and transmits the signal (downlink signal) to be transmitted to the termination device 3 by the TDM method, and the optical splitter 7 transfers the multiplexed downlink signal to each termination device 3 as it is. Further, a signal (uplink signal) transmitted from the terminal device 3 to the terminal device 2 is multiplexed by the optical splitter 7 by the TDMA method and transmitted to the terminal device 2.

  For example, the upper apparatus 1 is a base station apparatus section of a radio base station in a mobile network, and the lower apparatus 4 is a radio apparatus section of a radio base station in the mobile network. The subordinate device 4 may be connected to Q (Q is an integer of 1 or more) user devices 5 via a subordinate network. In the figure, Q user devices 5 are described as user devices 5-1 to 5-Q. The user device 5 starts transmission of uplink data based on the scheduling information notified from the higher-level device 1. Uplink data is data of uplink communication from the terminal device 3 to the terminal device 2.

  Here, consider a method in which the terminal device 2 performs bandwidth allocation to the terminal device 3. The communication speed from the subordinate device 4 to the terminal device 3 and the communication speed from the terminal device 3 to the terminal device 2 are not necessarily equal. In the present embodiment, the communication speed from the lower apparatus 4 to the terminal apparatus 3 is lower than the communication speed from the terminal apparatus 3 to the terminal station apparatus 2, and uplink data arrives simultaneously from the lower apparatus 4 to a plurality of terminal apparatuses 3. Is assumed. Note that the communication system to which the present embodiment is applied is not limited to the mobile network, and may be any communication system in which uplink data arrives at a plurality of terminal devices 3 at a predetermined time.

  FIG. 7 is a diagram showing a data transfer flow from the terminal device 3 to the terminal device 2 when a general prior art is used. Here, it is assumed that the communication system 10 is applied to a mobile network. In addition, it is assumed that the terminating device 3 can start the transfer without transmitting the MPCP Report, that is, fixed bandwidth allocation, Non status reporting DBA (NSR-DBA), or mobile DBA.

  Here, the length of the uplink data arriving at the termination device 3 is the length of one subframe. For example, an LTE (Long Term Evolution) TDD (Time Division Duplex) frame is composed of 9 subframes of 1 ms, and the uplink and downlink are subframed according to the uplink and downlink traffic. The pattern assigned to is switched. By this switching, it is possible to flexibly set the ratio of the uplink and downlink communication times. That is, the length of one subframe is a time that is a unit of communication when the user apparatus 5 transmits uplink data to the lower apparatus 4, and communication when the terminal apparatus 3 receives the uplink data from the lower apparatus 4. It is also a unit of time.

  In the figure, when upstream data arrives at the terminal device 3-1 and the terminal device 3-2 simultaneously from the respective lower devices 4, each of the terminal device 3-1 and the terminal device 3-2 has arrived. Is transferred to the terminal device 2. After the end of one subframe, the terminal device 2 grants transmission permission in the order of the terminal device 3-1 and the terminal device 3-2. For this reason, the termination device 3-2 waits for the end of transmission of the uplink data from the termination device 3-1 (waits for transmission), and then starts the transfer of the uplink data. As described above, when there are a plurality of termination devices 3, a delay (control delay) occurs from completion of reception of uplink data to completion of transfer to the terminal device 2 due to transmission standby. This control delay increases as the number of terminal devices 3 increases. Therefore, in the present embodiment, the allocation amount of the termination devices 3-1 and 3-2 is divided to increase the number of transmission permission allocations, and uplink data transfer is started before the end of one subframe. This suppresses an increase in control delay due to transmission standby.

  FIG. 2 is a functional block diagram of the terminal device 2 according to the present embodiment, in which only functional blocks related to the present embodiment are extracted and shown. The terminal device 2 includes a higher-level transmission / reception unit 201, a lower-level transmission / reception unit 202, an allocation amount determination unit 203, an allocation count determination unit 204, and a band allocation unit 205.

  The upper transmission / reception unit 201 is an interface responsible for data transmission / reception with the upper apparatus 1. The lower transmission / reception unit 202 is an interface responsible for data transmission / reception with the terminal device 3. The lower transmission / reception unit 202 further has a function of measuring the amount of uplink traffic of each terminal device 3. The lower transmission / reception unit 202 notifies the allocation amount determination unit 203 of the measured uplink traffic amount.

The allocation amount determination unit 203 determines a bandwidth amount for each terminal device 3 to transmit data received from the lower device 4 to the terminal device 2 by the terminal device 3 at a predetermined time such as the length of one subframe. To do. The bandwidth amount determined for the termination device 3-i (i is an integer of 1 to P) is defined as a total bandwidth amount TA [i]. For example, the allocation amount determination unit 203 estimates the traffic amount of the next subframe from the transition of the past uplink traffic amount of each terminal device 3, and determines the total allocation amount.
The allocation number determination unit 204 arbitrarily determines the allocation number N according to the number of the terminal devices 3 and the required delay amount of the system.

  The bandwidth allocation unit 205 is an allocation amount in one divided allocation based on the total allocation amount of each terminal device 3 determined by the allocation amount determination unit 203 and the allocation number determined by the allocation number determination unit 204. Calculate a split quota. For example, the bandwidth allocation unit 205 divides the total allocation amount TA [i] by the allocation count N to obtain the divisional allocation amount A [i] in one allocation of the terminal device 3. The bandwidth allocation unit 205 generates a transmission permission based on the divided allocation amount of each terminal device 3. The transmission permission includes a transmission start time and a transmission permission amount. The transmission permission information generated by the bandwidth allocating unit 205 is notified to the terminating device 3 via the lower-level transmission / reception unit 202.

  Each terminal device 3 may transmit in advance a transmission request in which the requested amount of uplink data is set before receiving the uplink data from the lower device 4 (before the start of the subframe). The lower-level transmission / reception unit 202 of the terminal device 2 outputs the transmission request received from the termination device 3 to the allocation amount determination unit 203. The allocation amount determination unit 203 determines the total allocation amount of the terminating device 3 based on the uplink data amount indicated by the transmission request.

Moreover, although the allocation amount determination part 203 showed the example which determines a total allocation amount by dynamic bandwidth allocation (DBA: Dynamic Bandwidth Allocation) above, each terminal is determined by fixed bandwidth allocation (FBA: Fixed Bandwidth Allocation). A fixed total allocation amount may be allocated to the device 3. In this case, it is not necessary to acquire information from the lower transmission / reception unit 202.
As described above, the present embodiment can be applied to fixed bandwidth allocation, Non status reporting DBA, and mobile DBA that can start transfer while the terminal device 3 is receiving data, but the terminal device 3 transmits a request for upstream data in advance. It can also be applied to cases.

  FIG. 3 is a diagram showing a data transfer flow from the terminal device 3 to the terminal device 2 when the bandwidth allocation method of this embodiment is used. In the figure, an example is shown in which the number N of allocations is 2, and bandwidths are allocated to the terminal device 3-1 and the terminal device 3-2. The bandwidth allocating unit 205 divides the total allocation amount TA [1] of the termination device 3-1 and the total allocation amount TA [2] of the termination device 3-2 into two, respectively, and divides the allocation allocation amount into the termination device 3-1. A [1] is allocated, and the divided allocation amount A [2] is allocated to the terminal device 3-2. The divided allocation amounts A [1] and A [2] per one time of the terminal devices 3-1 and 3-2 are ½ of the total allocation amount shown in FIG. 7.

  The bandwidth allocating unit 205 performs the termination device 3 at the timing when the time t3 that is 1/2 (= 1 / N) of the length K (= t2−t1) of the subframe from the time t1 to the time t2 has passed. -1 and the terminating device 3-2 are given a transmission opportunity of the first divided band. In the figure, the first transmission opportunity is given to the terminal device 3-1, and then the first transmission opportunity is given to the terminal device 3-2. Further, the bandwidth allocation unit 205 gives the second transmission opportunity to the terminal devices 3-1 and 3-2 after the time t 2 when the subframe ends. That is, the transmission permission of the terminating device 3-1 generated by the bandwidth allocating unit 205 indicates time t3 (= t1 + K / 2), time t2 (= t3 + K / 2), and divided allocation amount A [1]. Further, the transmission permission of the terminating device 3-2 generated by the bandwidth allocating unit 205 indicates time t4 (t3 + k1 ≦ t4 <t2-k2), time t5 (= t4 + K / 2), and divided allocation amount A [2]. . k1 is the time required for the terminal device 3-1 to transmit uplink data with the divided allocation amount A [1], and k2 is the time required for the terminal device 3-2 to transmit uplink data with the divided allocation amount A [2]. . Such bandwidth allocation can reduce the control delay.

  As can be seen from FIG. 3, the control delay can be reduced as the number of times of allocation N is increased. It should be noted that the total allocation amount may be divided for all terminal devices 3, or the total allocation amount may be divided only for some of the terminal devices 3. Further, the first to Nth divided band amounts of one terminal device 3 may not be the same.

[Second Embodiment]
The second embodiment will be described with reference to FIG. Below, it demonstrates centering on the difference with 1st Embodiment.

The configuration of the communication system of this embodiment is a configuration in which the terminal station device 2 of the communication system 10 of the first embodiment shown in FIG. 1 is replaced with a terminal station device 12 shown in FIG.
In the present embodiment, the terminal station device 12 determines the total allocation amount for each terminal device 3 based on the notification information from the higher-level device 1. The notification information from the host device 1 is scheduling information in the mobile network, for example. The scheduling information indicates a schedule for uplink communication in the mobile network, and is information that enables acquisition of the time during which the lower apparatus 4 performs uplink communication and the amount of uplink communication data. For example, the scheduling information is information related to radio channel allocation between the lower-level device 4 and the user device 5, and includes allocation destination information indicating the user device 5 to which the radio resource is allocated, and resource indicating the allocated radio resource. The information includes information and communication destination information indicating the lower-level device 4 that is a communication partner of the user device 5.

  FIG. 4 is a functional block diagram of the terminal device 12 according to the present embodiment, in which only functional blocks related to the present embodiment are extracted and shown. In this figure, the same parts as those of the terminal device 2 according to the first embodiment shown in FIG. The terminal device 12 is different from the terminal device 2 of the first embodiment in that the terminal device 12 further includes an information extracting unit 501 and a quota determining unit 502 instead of the quota determining unit 203. .

  The information extraction unit 501 acquires scheduling information from the host device 1, converts the information for internal processing, and notifies the allocation determination unit 502 of the information. For example, the information extraction unit 501 acquires information on radio resources allocated to transmission of the uplink signal of the user apparatus 5 from the scheduling information, and determines the transmission timing and transmission amount of the uplink communication of the user apparatus 5 based on the acquired information. calculate. Furthermore, when the information extraction unit 501 acquires information on the lower device 4 that is the communication partner of the user device 5 from the scheduling information, the information extraction unit 501 calculates the uplink transmission transmission timing and transmission amount for each lower device 4 and allocates the amount determination unit 502. Notify The allocation amount determination unit 502 determines the total allocation amount to each terminal device 3 using the information notified from the information extraction unit 501. For example, the allocation amount determination unit 502 determines the uplink arrival at the termination device 3 in the next subframe from the time when the scheduling information is received and the transmission timing and transmission amount of the uplink communication of the subordinate device 4 under the termination device 3. Estimate the amount of data and determine the total quota. The operation of other functional blocks is the same as that of the first embodiment.

  Since the terminal station device 12 of this embodiment determines the allocation amount of each terminal device 3 based on the scheduling information, the calculation accuracy of the uplink data amount is improved, and the appropriate bandwidth allocation amount can be calculated. Therefore, in addition to low-delay uplink transmission, it is possible to realize high bandwidth utilization efficiency.

  Note that the terminal station device 12 is provided with a dedicated communication path for receiving scheduling information with the higher-level device 1, and the scheduling information is transmitted from the higher-level device 1 with other downlink communications. Receiving with a different communication interface. However, the higher-level device 1 may transmit scheduling information via the same communication interface as other downlink communication. In this case, the terminal device 12 does not have an interface for receiving scheduling information, and the higher-level transmission / reception unit 201 snoops scheduling information from the main signal received from the higher-level device 1 and transfers the scheduling information to the information extraction unit 501.

[Third Embodiment]
In this embodiment, in the terminal station apparatus of the first embodiment or the terminal station apparatus of the second embodiment, the allocation number N is adaptively determined so as to minimize the delay.

The configuration of the communication system of this embodiment is a configuration in which the terminal station device 2 of the communication system 10 of the first embodiment shown in FIG. 1 is replaced with a terminal station device 22 shown in FIG.
FIG. 5 is a functional block diagram of the terminal device 22 according to the present embodiment, in which only functional blocks related to the present embodiment are extracted and shown. In this figure, the same parts as those of the terminal device 2 according to the first embodiment shown in FIG. The terminal station device 22 is different from the terminal station device 2 of the first embodiment in that an allocation number determining unit 601 is provided instead of the allocation number determining unit 204. The operation of other functional blocks is the same as that of the first embodiment.

  When the present embodiment is applied to the second embodiment, the allocation number determining unit 601 of the terminal station device 22 shown in FIG. 5 is provided instead of the allocation number determining unit 204 of the terminal device 12 shown in FIG. Just do it. The operation of other functional blocks is the same as that of the second embodiment.

  The allocation number determination unit 601 determines the allocation number N based on the allocation amount determined by the allocation amount determination unit 203 (or the allocation amount determination unit 502). In the passive optical communication network, it is necessary to provide overhead for laser ON / OFF and clock synchronization when the terminal device performs uplink transmission to the terminal device. That is, as the number N of allocations increases, the total amount of overhead in the data increases. Therefore, the allocation number determination unit 601 prevents the total amount of uplink data and overhead from exceeding the total bandwidth of the passive optical communication network (the upper limit bandwidth at which the terminal station device 22 can receive data from the plurality of terminal devices 3). The number N of assignments is determined. Instead of the total bandwidth of the passive optical communication network, a preset default bandwidth smaller than the total bandwidth of the passive optical communication network may be used as the threshold value.

  According to the present embodiment, the terminal station device 22 can perform uplink transmission with the minimum control delay that can be realized by making maximum use of the total bandwidth of the passive optical communication network.

[Fourth Embodiment]
In this embodiment, in the terminal station device of the first embodiment or the terminal station device of the second embodiment, the allocation number N is adaptively determined so that the use band is minimized.

The configuration of the communication system of the present embodiment is a configuration in which the terminal station device 2 of the communication system 10 of the first embodiment shown in FIG. 1 is replaced with a terminal station device 32 shown in FIG.
FIG. 6 is a functional block diagram of the terminal device 32 according to the present embodiment, in which only functional blocks related to the present embodiment are extracted and shown. In this figure, the same parts as those of the terminal device 2 according to the first embodiment shown in FIG. The terminal device 32 is different from the terminal device 2 of the first embodiment in that an allocation number determining unit 701 is provided instead of the allocation number determining unit 204. The operation of other functional blocks is the same as that of the first embodiment.

  When the present embodiment is applied to the second embodiment, an allocation number determining unit 701 of the terminal station device 32 shown in FIG. 6 is provided instead of the allocation number determining unit 204 of the terminal station device 12 shown in FIG. Just do it. The operation of other functional blocks is the same as that of the second embodiment.

  The allocation count determining unit 701 determines the minimum allocation count N whose control delay is less than a predetermined request delay time. The control delay is the time from the end of the subframe until the end device 3 finishes transmitting the uplink data received from the lower level device 4 in the subframe to the terminal device 32. For example, the maximum delay time is (subframe length) × (radio rate of user apparatus 5) / (uplink transmission rate from terminal apparatus 3 to terminal station apparatus 32) / (assignment count N) × (terminal It can be approximated by the number of terminal devices 3 accommodated in the station device 32). However, Σ (the radio rate of the user device 5) ≦ (the transmission rate of uplink communication from the terminal device 3 to the terminal device 32). As a result, the terminal device 32 can perform uplink transmission that satisfies the specified request delay time while minimizing the use band of the passive optical communication network.

According to the above-described embodiment, the plurality of terminal devices transmit data received from the lower device to the terminal device connected to the higher device by time division multiple access. The allocation amount determination unit of the terminal device determines a bandwidth amount for transmitting data received in a predetermined time (for example, one subframe) to the terminal device for each of the plurality of terminal devices. Further, the bandwidth allocating unit of the terminal device allocates a divided bandwidth amount obtained by dividing the determined bandwidth amount to at least some of the terminating devices, and divides the data received by the terminal device at a predetermined time into the divided bandwidth amounts. The timing for transmission to the station apparatus is assigned so that the start of transmission of the first data is before the end of the predetermined time.
As a result, in a communication system in which a higher-level device and a lower-level device are connected via a passive optical communication network system including a terminal station device and a termination device, when a plurality of termination devices simultaneously receive upstream data from each lower-level device. The delay time due to waiting for transmission can be reduced.

  You may make it implement | achieve the function of the terminal station apparatus 2, 12, 22, and 32 in embodiment mentioned above with a computer. In that case, a program for realizing the functions of the terminal devices 2, 12, 22, and 32 is recorded on a computer-readable recording medium, and the program recorded on the recording medium is read into a computer system. It may be realized by executing. Here, the “computer system” includes an OS and hardware such as peripheral devices. The “computer-readable recording medium” refers to a storage device such as a flexible medium, a magneto-optical disk, a portable medium such as a ROM and a CD-ROM, and a hard disk incorporated in a computer system. Furthermore, the “computer-readable recording medium” dynamically holds a program for a short time like a communication line when transmitting a program via a network such as the Internet or a communication line such as a telephone line. In this case, a volatile memory inside a computer system serving as a server or a client in that case may be included and a program held for a certain period of time. The program may be a program for realizing a part of the functions described above, and may be a program capable of realizing the functions described above in combination with a program already recorded in a computer system.

  The embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration is not limited to this embodiment, and includes designs and the like that do not depart from the gist of the present invention.

  It can be used for a system that performs communication by time division multiple access.

DESCRIPTION OF SYMBOLS 1 High-order apparatus 2, 12, 22, 32 Terminal station apparatus 3, 3-1 to 3-P Termination apparatus 4, 4-1 to 4-P Lower apparatus 5 User apparatus 6 Optical fiber 7 Optical splitter 10 Communication system 201 Upper transmission / reception Unit 202 Lower-level transmission / reception unit 203, 502 Allocation amount determination unit 204, 601, 701 Allocation count determination unit 205 Band allocation unit 501 Information extraction unit

Claims (5)

A terminal device connected to a plurality of terminal devices that transmit received data by time division multiple access,
For each of the plurality of terminal devices, an allocation amount determination unit that determines a bandwidth amount for transmitting the data received in a predetermined time to the terminal device;
Assigning a divided band amount obtained by dividing the bandwidth amount to at least a part of the terminal devices, and a timing at which the terminal device divides the data received at the predetermined time into the divided band amounts and transmits the divided data to the terminal device, A bandwidth allocation unit that allocates the start of transmission of the first data so as to be a timing obtained by adding a time obtained by dividing the predetermined time by the number of divisions of the bandwidth to the start time of the predetermined time ;
A terminal device comprising: The allocated amount determination unit calculates a data amount received by the terminal device based on information indicating a communication schedule of a device lower than the terminal device, and determines the bandwidth amount based on the calculated data amount;
The terminal device according to claim 1. As the band when said plurality of terminating device transmits data to the own device does not exceed the bandwidth of the upper, further comprising an allocation number determining section that determines the number of divisions of the bandwidth quantity,
The terminal device according to claim 1, wherein the terminal device is a terminal device. From the end of the predetermined time, the data to which the terminating device is received in the predetermined time so that the time until finishes transmitted to its own device is below a predetermined delay time, allocation number determination for determining the division number of the bandwidth quantity Further comprising
The terminal device according to claim 1, wherein the terminal device is a terminal device. A bandwidth allocation method executed by a terminal device connected to a plurality of terminal devices that transmit received data by time division multiple access,
For each of the plurality of terminal devices, an allocation amount determining step for determining a bandwidth amount for transmitting the data received in a predetermined time to the terminal station device;
Assigning a divided band amount obtained by dividing the bandwidth amount to at least a part of the terminal devices, and a timing at which the terminal device divides the data received at the predetermined time into the divided band amounts and transmits the divided data to the terminal device, A bandwidth allocation step for allocating the start of transmission of the first data so as to be a timing obtained by adding a time obtained by dividing the predetermined time by the division number of the bandwidth amount to the start time of the predetermined time ;
A bandwidth allocation method characterized by comprising:

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