Communication system, communication control method, and master station communication apparatus

Abstract

To implement more power saving and efficient resource allocation in a radio access network of a mobile communication network.SOLUTION: A communication system includes: a plurality of radio antenna devices for transmitting / receiving radio signals to / from a mobile terminal; and a signal processor for performing transmission / reception processing of signals with the mobile terminal through the radio antenna devices. The communication system includes: allocation means for allocating a communication rate and a communication method to an area corresponding to each of the radio antenna devices; and area merging means for merging a plurality of areas within a range where the communication rate and the communication method agree and a total value of request bands does not exceed the communication rate.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a communication system, a communication control method, and a master station communication device, and can be applied to a network of a wired section on the upper side (core side) from a wireless antenna connected to a mobile terminal (for example, a mobile phone terminal). [Background technology]

[0002] Conventionally, in a mobile communication network (a communication carrier's network), a wireless base station is divided into a slave station that communicates with a user device and a master station that controls the slave station. In addition, in a conventional mobile communication network, the master station and the slave station are connected by optical fiber, and multiple wireless devices are arranged in the wireless base station. Furthermore, in a conventional mobile communication network, the number of wireless devices per wireless base station is determined by the number of mobile terminals that the wireless base station should handle and the amount of traffic that is set by predicting the frequency of use. Furthermore, in a conventional mobile communication network, a mobile terminal must be able to connect to a wireless base station and be usable even during times of high traffic, which results in a considerable number of wireless devices.

[0003] On the other hand, the traffic generated by mobile communication networks generally varies depending on the time of day, with low traffic late at night and early in the morning, and high traffic from daytime to night. In recent years, 5G services have been launched, and high-definition image transmission services and services aimed at advancing cities using digital twin technology have become widespread. As such, services on mobile communication networks are now large-capacity and diverse, and the difference in traffic is becoming increasingly large.

[0004] Conventionally, wireless base stations in mobile communication networks are installed assuming high traffic times, and they operate even during low traffic times, wasting power. Therefore, it is necessary to operate them in a way that satisfies QoS (Quality of Service) while reducing power consumption as much as possible.

[0005] In recent years, as the speed of wireless access networks provided by mobile communication networks increases, the area (cell) covered by a base station device becomes smaller, and as a result, the number of base station devices that need to be installed to configure a mobile communication network increases. For this reason, in conventional mobile communication networks, passive optical network (PON) systems, in which multiple subscribers share a single optical transmission line, are being considered as networks for accommodating multiple base station devices.

[0006] In a PON system, one optical line terminal (OLT) installed at a telecommunications carrier's central office is connected to multiple subscriber-side optical network units (ONUs) via optical splitters. The OLT dynamically allocates upstream bandwidth to multiple ONUs, for example, 32 ONUs, using the time division multiple access (TDMA) method, thereby achieving high bandwidth utilization efficiency. 10Gbps class PON systems are currently being introduced in optical access networks.

[0007] As power saving techniques for a wireless access network using the above-mentioned PON, there are techniques described in Patent Document 1 and Non-Patent Document 1.

[0008] The technology described in Patent Document 1 enables a reduction in power consumption throughout the network by controlling the sleep of ONUs connected to a small cell base station in cooperation with the sleep control of the small cell base station to which a small number of mobile terminals are linked in a wireless access network of a mobile communication network.

[0009] Non-Patent Document 1 describes a method of allocating an optimal communication method and communication rate to a wireless access network according to the traffic volume. In the method described in Non-Patent Document 1, a 500m mesh area is set as a cell area to be allocated, and the communication rate is set according to the required bandwidth of one mesh area (required bandwidth of ONU). In other words, the method described in Non-Patent Document 1 is a method of increasing the communication rate during times when the traffic volume is high, and decreasing the communication rate during times when the traffic volume is low. In the method described in Non-Patent Document 1, for example, during a time period when the required bandwidth of the ONU exceeds 100Gbps, communication is performed at 200Gbps Point to Point (PtP), and during a time period when the required bandwidth of the ONU does not exceed 100Gbps, communication is performed at 10Gbps or 100Gbps Multi Point (PtMP). In general, the lower the communication rate of a transceiver used in an ONU, the lower the power consumption can be, so that power consumption can be reduced more by allocating an optimal communication rate according to the required bandwidth than by a method that matches the peak value. [Prior art documents] [Patent documents]

[0010] [Patent Document 1] JP 2018-207457 A [Non-patent literature]

[0011] [Non-Patent Document 1] Hiroyuki Saito, Yoshihiro Nakahira, Masayuki Kashima, Masahiro Sarashina, "A Study on Reducing Power Consumption of Optical Access Networks for Beyond 5G," Communications Conference Proceedings 2, B-8-2, 2023 General Conference of the Institute of Electronics, Information and Communication Engineers Summary of the Invention [Problem to be solved by the invention]

[0012] However, in the wireless access network described in Patent Document 1, low power consumption in the network is achieved by putting the ONU to sleep after the small cell bandwidth has already been allocated, so if base station equipment and ONUs are placed assuming times of high traffic, there is a problem of unnecessary power consumption.

[0013] In addition, in the wireless access network described in Non-Patent Document 1, one ONU is assigned to one mesh area according to the bandwidth required by the ONU, and one mesh area is always assigned a communication rate of 10 Gbps, 100 Gbps, or 200 Gbps. Therefore, even in areas or time periods with extremely low traffic, the minimum communication rate is 10 Gbps, and the minimization of power consumption is limited. For example, in a conventional wireless access network, even if a communication rate of 10 Gbps is assigned to each of four mesh areas or the number of mesh areas is 16, the communication rate of 10 Gbps is assigned to all areas, which increases the power consumption on the user side.

[0014] In view of the above problems, there is a demand for a communication system, a communication control method, and a master station communication device that can realize more efficient resource allocation with less power consumption in a wireless access network of a mobile communication network. [Means for solving the problem]

[0015] A first aspect of the present invention includes a communication network system including a plurality of wireless antenna devices that transmit and receive wireless signals to and from a mobile terminal, a signal processing device that processes transmission and reception of signals to and from the mobile terminal via the wireless antenna devices, and data transmission between each of the wireless antenna devices and the signal processing devices, the communication network system having a slave station communication device connected to each of the wireless antenna devices, a master station communication device connected to the signal processing device, and a transmission path that connects the master station communication device to each of the slave station communication devices, the communication network system further includes an allocation means that allocates a communication rate and a communication method to an area corresponding to each of the wireless antenna devices, and an area merge means that selects one of the areas as a reference area, and when the communication rate and communication method of the reference area and an adjacent area adjacent to the reference area are the same and the sum of the required bandwidth of the reference area and the required bandwidth of the adjacent area is equal to or less than the communication rate, merges the reference area and the adjacent area into one merged area, and performs an area merge process that allocates a communication rate and a communication method to the merged area.

[0016] A second aspect of the present invention is a communication control method performed by a communication system including a plurality of wireless antenna devices that transmit and receive wireless signals to and from a mobile terminal, a signal processing device that processes transmission and reception of signals to and from the mobile terminal via the wireless antenna devices, and a communication network system that transmits data between each of the wireless antenna devices and the signal processing devices, the communication network system having a slave station communication device connected to each of the wireless antenna devices, a master station communication device connected to the signal processing devices, and a transmission path that connects the master station communication device to each of the slave station communication devices, the communication system having an allocation means and an area merging means, the allocation means assigning a communication rate and a communication method to an area corresponding to each of the wireless antenna devices, the area merging means selecting one of the areas as a reference area, and performing area merging processing in which, when the communication rate and the communication method of the reference area and an adjacent area adjacent to the reference area are all the same, and the sum of the required bandwidth of the reference area and the required bandwidth of the adjacent area is equal to or less than the communication rate, the reference area and the adjacent area are merged to form a single merged area, and a communication rate and a communication method are assigned to the merged area.

[0017] The third aspect of the present invention is a communication network system for transmitting data between a plurality of wireless antenna devices which transmit and receive wireless signals to and from a mobile terminal, and a signal processing device which processes transmission and reception of signals to and from the mobile terminal via the wireless antenna devices, the system comprising: a master station communication device which connects the signal processing device to a slave station communication device connected to each of the wireless antenna devices via a transmission path; an allocation means which allocates a communication rate and a communication method to an area corresponding to each of the wireless antenna devices; and an area merging means which performs area merging processing which selects one of the areas as a reference area, and when the communication rates and communication methods of the reference area and an adjacent area adjacent to the reference area are all the same and the sum of the required bandwidth of the reference area and the required bandwidth of the adjacent area is less than or equal to the communication rate, merges the reference area and the adjacent area to form a single merged area, and assigns a communication rate and a communication method to the merged area. Effect of the Invention

[0018] According to the present invention, it is possible to realize more power-saving and efficient resource allocation in a radio access network of a mobile communication network. [Brief description of the drawings]

[0019] [Figure 1] 1 is a block diagram showing an overall configuration of a communication system according to a first embodiment. [Diagram 2] 10 is a flowchart showing an example of an area merge process performed by a communication control unit according to the first embodiment. [Diagram 3] FIG. 2 is a diagram illustrating an example of an area configuration in the form of a map according to the first embodiment. [Figure 4] FIG. 4 is a diagram showing an example of a required bandwidth corresponding to each area according to the first embodiment. [Diagram 5] FIG. 2 is a diagram showing an example of provisionally allocated communication rates and communication methods corresponding to each area according to the first embodiment. [Figure 6] FIG. 2 is a diagram illustrating provisionally allocated communication rates corresponding to each area in the form of a map according to the first embodiment. [Figure 7] 1 is a diagram illustrating, in map form, the configuration of each area after area merge processing in the first embodiment. FIG. [Figure 8] FIG. 4 is a diagram showing a power saving effect in the communication system according to the first embodiment. [Figure 9] 13 is a flowchart illustrating an example of an area merge process performed by a communication control unit according to the second embodiment. [Figure 10] 13 is a diagram illustrating, in map format, the configuration of each area after area merge processing in the second embodiment. FIG. [Figure 11] FIG. 11 is a diagram illustrating an example of a required bandwidth corresponding to each area according to the second embodiment. [Figure 12] FIG. 11 is a diagram showing a power saving effect in the communication system according to the second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] (A) Main embodiment A first embodiment of a communication system, a communication control method, and a master station communication device according to the present invention will be described below in detail with reference to the drawings.

[0021] (A-1) Configuration of the First Embodiment FIG. 1 is a block diagram showing the overall configuration of a communication system 1 according to the first embodiment.

[0022] The communication system 1 includes N RUs (Radio Units) 30 (30-1 to 30-N) as antenna devices constituting a radio access network in a mobile communication network (for example, a so-called 5G mobile communication network), DU / CUs (Distributed Unit / Centralized Unit) 50 as a signal processing device that controls each RU 30 to form a radio access network, an optical communication network system 100 as a communication network system that connects each RU 30 and the DU / CU 50 by optical communication (PON), and a ROADM 40 that connects the DU / CU 50 and the optical communication network system 100. The RU 30 transmits and receives radio signals to and from a mobile terminal TE that subscribes to the communication system 1 (mobile communication network). The DU / CU 50 communicates with the mobile terminal TE via the RU 30.

[0023] The optical communication network system 100 has an OLT 10 as a parent station communication device and N ONUs 20 (20-1 to 20-N) as child station communication devices. The OLT 10 is connected to an optical fiber 80, which is branched into N (as many as the number of ONUs 20) by a splitter 70, and each branch is connected to the ONUs 20-1 to 20-N. Note that the configuration for branching the optical fiber 80 is not limited to the configuration in FIG. 1, and a configuration in which multiple splitters 70 are used to branch the optical fiber 80 in multiple stages (hierarchically) may also be used.

[0024] The ONUs 20-1 to 20-9 are connected to the RUs 30-1 to 30-N, respectively. A reconfigurable optical add / drop multiplexer (RADM) 40 serving as an optical add / drop device is inserted between the OLT 10 of the communication system 1 and the DU / CU 50. A core network 60 (e.g., a core network of a communication carrier) is connected to the upper side of the DU / CU 50. The DU / CU 50 has a DU function for processing the physical layer of signals (e.g., modulation, demodulation, etc.) and controlling communication in the MAC layer, and a CU function for controlling packet communication between the RUs 30 and the core network 60, managing radio resources of each RU 30, etc.

[0025] In the communication system 1, each RU 30 is responsible for wireless communication within one mesh area, and connects to a mobile terminal TE within the cell under the control of the DU / CU 50. In the following, for ease of explanation, the "mesh area" will also be simply referred to as the "area."

[0026] Next, the internal configuration of the OLT 10 will be described.

[0027] As shown in FIG. 1, the OLT 10 includes a communication control unit 11, an AWG 12, an OLT concentrator unit 13 (13-1, 13-2), M (M is an integer greater than or equal to 2) 10G transceivers 14 (14-1 to 14-M), a transceiver 15, L (L is an integer greater than or equal to 2) 100G transceivers 16 (16-1 to 16-L), a transceiver 15, a transceiver 17, and a 200G converter 18.

[0028] The communication control unit 11 is responsible for the function of controlling communication in the entire OLT 10 .

[0029] The 10G transceiver 14 and the 100G transceiver 16 are optical transceivers capable of communication at 10 Gbps and 100 Gbps, respectively (EO / OE conversion possible). The 200G converter 18 is an optical interface converter capable of relay communication at 200 Gbps. The combination of communication speeds and numbers of each transceiver / converter is not limited to the above example, and various combinations can be applied.

[0030] In the OLT 10, the AWG 12 is connected to the PON side (optical fiber 80), and the transceiver 15, the transceiver 17, and the 200G converter 18 are connected to the upper side (ROADM 40). The OLT concentrator 13-1 concentrates the communications of the lower-side 10G transceivers 14-1 to 14-M and connects them to the upper-side transceiver 15. The OLT concentrator 13-2 concentrates the communications of the lower-side 100G transceivers 16-1 to 16-M and connects them to the upper-side transceiver 17. The 200G converter 18 is directly connected between the AWG 12 and the upper side (ROADM 40).

[0031] In the OLT 10, each transceiver / converter is assigned and connected to one of the ONUs 20 by the AWG 12. The ONU 20 connected to the 10G transceiver 14 or 100G transceiver 16 by the AWG 12 is connected to the upstream side by a PtMP (Point to Multi Point) communication method. On the other hand, the ONU 20 connected to the 200G converter 18 by the AWG 12 is connected to the upstream side by a PtP (Point to Point) communication method.

[0032] Next, the internal configuration of each ONU 20 will be described.

[0033] As shown in FIG. 1, each ONU 20 has a transceiver 22 for connecting to the upper side (PON side) and a user-side interface 21 for connecting to the RU 30 on the lower side (user side / subscriber side). The transceiver 22 communicates with the upper side (PON side) at a communication rate according to the control from the OLT 10 as the maximum communication speed. Here, the communication rate allocated from the OLT 10 (communication control unit 11) to the ONU 20 (transceiver 22) is the communication speed supported by the transceiver / converter allocated by the OLT 10 (communication control unit 11). For example, when the 10G transceiver 14-1 is allocated to the ONU 20-1 by the OLT 10 (communication control unit 11), the communication rate of the transceiver 22 of the ONU 20-1 is 10 Gbps. In this case, the ONU 20-1 (transceiver 22) communicates with the upper side at a communication rate of 10 Gbps using the PtMP method.

[0034] It is assumed that the communication control unit 11 of the OLT 10 holds information on each RU 30 (each area). It is assumed that the communication control unit 11 assigns an identification number (hereinafter referred to as "area number") to each area (each RU 30) and manages them. Here, it is assumed that area numbers 1 to 9 are assigned to areas A-1 to A-9 (RUs 30-1 to 30-9), respectively. It is also assumed that each communication control unit 11 holds information on the communication bandwidth (hereinafter simply referred to as "requested bandwidth") requested by each area (each RU 30). It is also assumed that the communication control unit 11 holds information on the positional relationship (map information) of each area. There is no limitation on the method by which the communication control unit 11 holds various information (hereinafter referred to as "area information") on each area (each RU 30). For example, the communication control unit 11 may hold the area information from an upper-level device (for example, the DU / CU 50 or an orchestrator (not shown) on the core network 60) that controls each RU 30.

[0035] Here, the communication control unit 11 performs a process (hereinafter, also referred to as a "provisional allocation process") of provisionally allocating the communication rate and communication method of each area (mesh area) in consideration of the required bandwidth of each area, etc. At this time, the method of the provisional allocation process is not limited, and various allocation methods (for example, the conventional allocation method described in Non-Patent Document 1, etc.) can be applied.

[0036] After the provisional allocation process for each area, the communication control unit 11 performs a process (hereinafter referred to as an "area merge process") to control each ONU 20, etc., to merge multiple areas that can be merged to form one area (hereinafter referred to as a "merged area"). In other words, the merged area is composed of multiple areas (mesh areas).

[0037] Next, an overview of the area merge process performed by the communication control unit 11 will be described.

[0038] The communication control unit 11 performs the area merging process by selecting an arbitrary area as an area that is the reference for the area merging process (hereinafter referred to as the "reference area"), extracting areas that can be merged from areas adjacent to the selected reference area to set them as a merging area, and further extracting areas that can be merged from areas adjacent to the merging area and merging them, repeating the process. Hereinafter, an area adjacent to the reference area or the merging area will be referred to as an "adjacent area." In this embodiment, the communication control unit 11 merges the adjacent area into the reference area to make them the same area if the reference area and the adjacent area adjacent to the reference area are assigned the same communication rate and communication method, and the sum of the required bandwidth of the reference area and the adjacent area is equal to or less than the assigned communication rate.

[0039] In this embodiment, only one ONU20 / RU30 operates in one merged area. In addition, here, an area having an ONU20 / RU30 that communicates in the merged area is called a "representative area". The communication control unit 11 selects a representative area in the merged area, and controls the RU30 / ONU20 in the representative area to represent the communication with the mobile terminal TE in the merged area. At this time, the communication control unit 11 may control the RU30 / ONU20 in the area other than the representative area in the merged area to stop or operate with less power. For example, if each RU30 / ONU20 supports a power-saving operation mode (so-called sleep mode) in which it operates with less power, the communication control unit 11 may operate the RU30 / ONU20 in the area other than the representative area in the merged area in the power-saving operation mode. In other words, in the communication system 1 of this embodiment, the merged area is generated, so that the RU30 / ONU20 in the area other than the representative area operates with less power, and therefore the overall system can be operated with less power than before. The area that the communication control unit 11 selects as the representative area within the merged area is not limited, and any area can be selected. For example, the communication control unit 11 may select the area that was initially selected as the reference area within the merged area as the representative area.

[0040] As described above, in this embodiment, the communication control unit 11 of the OLT 10 functions as an allocation unit that performs provisional allocation processing and an area merging unit that performs area merging processing.

[0041] (A-2) Operation of the First Embodiment Hereinafter, the operation of the OLT 10 (communication control unit 11) constituting the communication system 1 in the first embodiment (the communication control method according to the embodiment) will be described.

[0042] FIG. 2 is a flowchart showing an example of the area merge process performed by the communication control unit 11 in the first embodiment.

[0043] First, it is assumed here that at time T1, the communication control unit 11 performs a provisional allocation process and determines a provisional communication rate and communication method for each area (mesh area) in consideration of the required bandwidth, etc. (S100). After this, the communication control unit 11 transitions to an area merge process.

[0044] Next, the communication control unit 11 selects the area with the smallest area number as the reference area (S101).

[0045] Next, the communication control unit 11 searches for an unallocated adjacent area (an area for which the allocation of communication rate and communication method has not been completed after the provisional allocation process) to the reference area (S102), and if an unallocated adjacent area exists, the process proceeds to step S103, and if an unallocated adjacent area exists, the process proceeds to step S109. Note that if there are multiple adjacent areas to the reference area, the communication control unit 11 selects and processes the area with the smallest area number first.

[0046] If an unallocated adjacent area is present for the reference area in step S102, the communication control unit 11 selects one of the unallocated adjacent areas and compares the communication methods of the reference area and the adjacent area (S103). If both communication methods are PtMP (the communication methods match), the process proceeds to S104; if the communication methods are different, the communication rate and method determined in S101 are assigned to the reference area, and the process returns to step S102 described above.

[0047] In the above-mentioned step S103, if the communication methods of the reference area and adjacent area are both PtMP, the communication rates of the reference area and adjacent area are compared (S104), and if they are equal, proceed to S105, and if they are different, the communication rate and method determined in S101 are assigned to the reference area, and the process returns to the above-mentioned step S102.

[0048] If it is determined in step S104 that the communication rates of the reference area and the adjacent area are equal, the communication control unit 11 calculates the sum of the required bandwidth of the reference area and the required bandwidth of the adjacent area (S105).

[0049] Next, the communication control unit 11 compares the total value calculated in S104 with the communication rate to be allocated in the reference area (S106), and if the communication rate in the reference area is greater than the calculated total value, proceeds to step S107 described below, otherwise proceeds to step S108 described below.

[0050] If it is determined in step S106 above that the communication rate of the reference area is greater than the calculated total value, the communication control unit 11 merges the reference area and the adjacent area into a single merged area, assigns the communication rate and method determined for the reference area to the merged area, and further updates the merged area as the reference area (S107), and returns to step S102 above to operate.

[0051] If it is determined in step S106 above that the calculated total value is equal to or greater than the communication rate of the reference area, the communication control unit 11 does not merge the reference area with the adjacent area, but takes the communication rate and method already assigned to the reference area as the final allocation, updates the adjacent area as the reference area (S108), and returns to step S102 above to operate.

[0052] In the above-mentioned step S102, if there is no unallocated adjacent area to the reference area, the communication control unit 11 searches whether there is an unallocated area among areas that are not adjacent to the reference area (S109), and if there is an unallocated area, selects one of the unallocated adjacent areas and proceeds to S110, and if there is no unallocated adjacent area, terminates the area merge process.

[0053] If it is determined in step S109 above that there is an unallocated area among the areas that are not adjacent to the reference area, the communication control unit 11 updates the non-adjacent, unallocated area with the smaller area number as the reference area (S110), and returns to step S102 above to operate.

[0054] Next, a specific example in which the communication control unit 11 of the OLT 10 performs area merge processing will be described with reference to a flowchart shown in FIG.

[0055] FIG. 3 is a diagram illustrating, in the form of a map, areas A-1 to A-9 constituted by RUs 30-1 to 30-9.

[0056] Here, it is assumed that ONUs 20-1 to 20-9 are placed under the OLT 10, and RUs 30-1 to 30-9 are connected to the ONUs 20-1 to 20-9. It is also assumed that the RUs 30-1 to 30-9 form areas A-1 to A-9 as shown in FIG.

[0057] In FIG. 3, nine areas A-1 to A-9 are arranged in a 3×3 grid.

[0058] FIG. 4 is a diagram showing an example of required bandwidth corresponding to areas A-1 to A-9.

[0059] Here, as shown in FIG. 4, the required bandwidths corresponding to the areas A-1 to A-9 are assumed to be 2 Gbps, 1 Gbps, 12 Gbps, 1 Gbps, 5 Gbps, 3 Gbps, 1 Gbps, 110 Gbps, and 20 Gbps, respectively.

[0060] FIG. 5 is a diagram showing an example of provisionally allocated communication rates and communication methods corresponding to the areas A-1 to A-9.

[0061] FIG. 6 is a diagram showing provisionally allocated communication rates corresponding to areas A-1 to A-9 in the form of a map.

[0062] Here, as shown in Figures 5 and 6, the communication rates provisionally allocated to areas A-1 to A-9 are 10 Gbps, 10 Gbps, 100 Gbps, 10 Gbps, 10 Gbps, 10 Gbps, 10 Gbps, 200 Gbps, and 100 Gbps, respectively. Also, as shown in Figure 5, the communication method provisionally allocated to areas A-1 to A-9 is PtP only for area A-8, and PtMP for the other areas.

[0063] Here, an operation example is shown in which the number of areas (mesh areas) under the OLT 10 is 9 (N=9), but the number of areas under the OLT 10 is not limited to this. Furthermore, here, the communication rate and method provisionally assigned to each area are 10 Gbps PtMP, 100 Gbps PtMP, or 200 Gbps PtP, but are not limited to this and other communication rates and methods (e.g., 25 Gbps PtMP) may be used. Furthermore, the requested bandwidth is not limited to the example in FIG. 4 and any value may be applied.

[0064] As described above, here, an example will be described in which the communication control unit 11 performs the area merge process when the situations of the areas A-1 to A-9 are as shown in FIGS.

[0065] [Processing when the reference area is Area A-1] In step S101, the reference area is selected in ascending order of area number, so that the communication control unit 11 first selects area A-1 as the reference area.

[0066] Next, in step S102, since there are unassigned adjacent areas (areas A-2, A-4) to the reference area A-1, the communication control unit 11 selects area A-2 with the smaller area number and proceeds to step S103.

[0067] Next, in step S103, since the communication method of the reference area (area A-1) and the adjacent area (area A-2) is determined to be PtMP, the communication control unit 11 proceeds to step S104.

[0068] Next, in step S104, since the communication rates of both the reference area (area A-1) and the adjacent area (area A-2) are 10 Gbps, the communication control unit 11 proceeds to step S105.

[0069] Next, in step S105, the communication control unit 11 calculates 3 Gbps as the total required bandwidth for the reference area (area A-1) and the adjacent area (area A-2).

[0070] Next, in step S106, since the total requested bandwidth does not exceed the allocated communication rate of 10 Gbps, the communication control unit 11 proceeds to step S107.

[0071] Next, in step S107, the communication control unit 11 merges the reference area (area A-1) with the adjacent area (area A-2), and updates the merged area (hereinafter, this merged area is referred to as "area A-10") as the reference area. Furthermore, the communication control unit 11 assigns 10Gbps / PtMP (i.e., any one of the 10G transceivers 14) to the reference area (area A-10), and returns to step S102.

[0072] [Processing when the reference area is Area A-10] Next, the operation of the communication control unit 11 after the reference area becomes area A-10 (area A-1 and A-2 merged) will be described.

[0073] In this case, in step S102, the areas adjacent to the reference area (area A-10) are areas A-3, A-4, and A-5, so the communication control unit 11 selects area A-3 as the adjacent area (the area with the lowest unprocessed area number) and proceeds to step S103.

[0074] Next, in step S103, since the communication methods of the reference area (A-10) and the adjacent area (area A-3) are both PtMP, the communication control unit 11 proceeds to step S104.

[0075] Next, in step S104, since the communication rate of the reference area (A-10) is 10 Gbps and the communication rate of the adjacent area (area A-3) is 100 Gbps, the communication control unit 11 returns to step S102.

[0076] Next, in step S102, area A-4 is selected as a new adjacent area to the reference area (A-10), and the communication control unit 11 proceeds to step S103.

[0077] Next, in step S103, since the communication methods of the reference area (A-10) and the adjacent area (area A-4) are both PtMP, the communication control unit 11 proceeds to step S104.

[0078] Next, in step S104, since the communication rates of the reference area (A-10) and the adjacent area (area A-4) are both 10 Gbps, the communication control unit 11 proceeds to step S105.

[0079] Next, in step S105, the communication control unit 11 calculates 4 Gbps as the total required bandwidth for the reference area (area A-10) and the adjacent area (area A-4).

[0080] Next, in step S106, since the total requested bandwidth does not exceed the allocated communication rate of 10 Gbps, the communication control unit 11 proceeds to step S107.

[0081] Next, in step S107, the communication control unit 11 merges the reference area (area A-10) with the adjacent area (area A-4), and updates the merged area (hereinafter, this merged area is referred to as "area A-11") as the reference area. Furthermore, the communication control unit 11 assigns one 10Gbps / PtMP (any of the 10G transceivers 14) to the reference area (area A-11), and returns to step S102.

[0082] [Processing when the reference area is Area A-11] Next, the operation of the communication control unit 11 after the reference area becomes area A-11 (area A-1, A-2, and A-4 merged) will be described.

[0083] In this case, the communication control unit 11 selects area A-5 as an adjacent area to the reference area (area A-11), performs the processing of steps S103 to S107 as described above, and returns to the processing of step S102 described above, with the area obtained by merging the reference area (area A-11) and area A-5 (hereinafter, the merged area will be referred to as "area A-12") as the new reference area.

[0084] [Processing when the reference area is Area A-12] Next, the operation of the communication control unit 11 in a case where the reference area becomes area A-12 (area A-1, A-2, A-4, and A-5 merged) will be described.

[0085] In this case, the areas adjacent to the reference area (area A-12) are areas A-3, A-6, A-7, and A-8.

[0086] First, area A-3 is selected as an adjacent area to the reference area (area A-12), but since the communication rate of the reference area (A-12) is 10 Gbps and the communication rate of the adjacent area (area A-3) is 100 Gbps, area A-3 is not merged.

[0087] Next, area A-6 is selected as an adjacent area to the reference area (area A-12), but since the total communication bandwidth of the reference area (area A-12) and the adjacent area (A-6) is 12 Gbps, area A-6 is also not merged.

[0088] Next, area A-7 is selected as an adjacent area to the reference area (area A-12), but since the total communication bandwidth of the reference area (area A-12) and the adjacent area (A-6) is 11 Gbps, area A-7 is also not merged.

[0089] Next, area A-8 is selected as an adjacent area to the reference area (area A-12), but because the communication methods used by the reference area (A-12) and the adjacent area (area A-8) are different, area A-8 is also not merged.

[0090] Through the above processing, the communication control unit 11 merges areas A-1, A-2, A-4, and A-5 to obtain area A-12, and assigns a communication rate of 10 Gbps and a communication method PtMP (assignment of one of the 10G transceivers 14) to area A-12.

[0091] [Processing when other areas are used as the reference area] Thereafter, the communication control unit 11 selects areas A-6, A-7, A-8, and A-9 as reference areas and performs similar processing, but there are no areas that can be merged among these areas.

[0092] Therefore, the communication control unit 11 assigns the provisionally assigned communication rate / communication method to the areas A-6, A-7, A-8, and A-9. Specifically, 10 Gbps / PtMP is assigned to the area A-6, 10 Gbps / PtMP to the area A-7, 200 GBps / PtP to the area A-8, and 100 Gbps / PtMP to the area A-9.

[0093] As described above, as a result of the communication control unit 11 performing the area merge process, the areas A-1 to A-9 finally become in the state shown in FIG.

[0094] FIG. 7 is a diagram showing, in map format, the configuration of each area after the area merge process.

[0095] As shown in FIG. 7, the areas A-1, A-2, A-4, and A-5 out of the areas A-1 to A-9 are merged into one area A-12 by the area merge process.

[0096] (A-3) Effects of the First Embodiment According to the first embodiment, the following effects can be obtained.

[0097] In the communication system 1, after a communication rate / communication method is provisionally assigned to each area (mesh area), the number of ONUs 20 assigned overall can be reduced by area merging processing, making it possible to reduce power consumption overall.

[0098] FIG. 8 is a diagram showing the power saving effect in the communication system 1. As shown in FIG.

[0099] In Figure 8, for the above areas A-1 to A-9, the operating status of ONU 20 when the communication rate is provisionally assigned (provisional assignment state) (operating status in the state of Figure 5) is compared with the operating status of ONU 20 when the communication rate is determined after area merging (state after area merging process) (operating status in the state of Figure 7).

[0100] As shown in Fig. 8, in the provisional allocation state, six ONUs 20 with a communication rate of 10 Gbps, two ONUs 20 with a communication rate of 100 Gbps, and one ONU 20 with a communication rate of 200 Gbps (a total of nine ONUs 20) are in operation. On the other hand, in the state after the area merge processing, three ONUs 20 with a communication rate of 10 Gbps, two ONUs 20 with a communication rate of 100 Gbps, and one ONU 20 with a communication rate of 200 Gbps (a total of nine ONUs 20) are in operation. In other words, in the state after the area merge processing, the power consumption of three ONUs 20 with a communication rate of 10 Gbps is reduced.

[0101] Incidentally, in a typical ONU, the power consumption when operating at a communication rate of 10 Gbps is 3.3 W, when operating at a communication rate of 100 Gbps is 6.5 W, and when operating at a communication rate of 200 Gbps is 13 W. Therefore, as shown in Fig. 8, the total power consumption of ONUs 20-1 to 20-9 in the provisional allocation state is 45.8 W, and the total power consumption of ONUs 20-1 to 20-9 after the area merge process is 35.9 W, resulting in a reduction in power consumption of 9.9 W.

[0102] (B) Second embodiment A second embodiment of a communication system, a communication control method, and a master station communication device according to the present invention will be described below in detail with reference to the drawings.

[0103] (B-1) Configuration of the second embodiment The communication system 1 of the second embodiment can also be illustrated using FIG. 1, similarly to the first embodiment.

[0104] In the second embodiment, only a part of the area merge processing by the OLT 10 (communication control unit 11) is different, so the following describes only the parts of the area merge processing of the second embodiment that are different from the first embodiment.

[0105] The communication control unit 11 of the second embodiment differs from the first embodiment in that it takes into consideration "limitations on the OLT 10 side" or "limitations on the user side (RU 30 side)" when determining whether an adjacent area can be merged into a reference area in the area merge process. Details of the area merge process performed by the communication control unit 11 in the second embodiment will be described later.

[0106] (B-2) Operation of the Second Embodiment Hereinafter, the operation of the OLT 10 (communication control unit 11) constituting the communication system 1 in the second embodiment (the communication control method according to the embodiment) will be described.

[0107] FIG. 9 is a flowchart showing an example of the area merge process performed by the communication control unit 11 of the OLT 10 in the second embodiment.

[0108] The flowchart in Fig. 9 differs from the first embodiment in that step S201 has been added. The processing of the other steps is similar to that of the first embodiment, so detailed explanations will be omitted. Note that, although step S201 is inserted between steps S104 and S105 in the flowchart in Fig. 9, it may be inserted at other timings (for example, between steps S102 and S103, between steps S103 and S104, between steps S106 and S107, etc.).

[0109] In step S201, the communication control unit 11 performs a process of determining whether the reference area and the adjacent area can be merged based on "limitations on the OLT 10 side" or "limitations on the user side".

[0110] The "OLT 10-side limit" is, for example, the number of branches possible based on the OLT 10-side specifications (the upper limit number of areas that can be merged based on the OLT 10-side specifications; hereinafter, referred to as the "parent station side merge upper limit number"). For example, the communication control unit 11 may be configured to hold the parent station side merge upper limit number and to hold the parent station side merge upper limit number. In this case, in step S201, the communication control unit 11 may proceed to step S105 if the number obtained by adding 1 (the number of areas of the adjacent area) to the number of areas included in the reference area (the number of areas already merged) is equal to or less than the parent station side merge upper limit number, and may return to step S102 to operate if the number exceeds the parent station side merge upper limit number.

[0111] The "user-side (RU 30-side) restriction" is, for example, an upper limit number of areas that can be merged (hereinafter referred to as "user-side merge upper limit number") according to the specifications of each RU 30 (for example, the size of the area that can be covered, the number of wireless terminals that can be connected simultaneously, etc.). For example, the communication control unit 11 may be configured to hold the user-side merge upper limit number and to hold the user-side merge upper limit number. In this case, in step S201, if the number obtained by adding 1 (the number of areas in the adjacent area) to the number of areas included in the reference area is equal to or less than the user-side merge upper limit number, the communication control unit 11 may proceed to step S105, and if the number exceeds the user-side merge upper limit number, the communication control unit 11 may determine that merging is not possible and return to step S102 for operation.

[0112] In the second embodiment, the communication control unit 11 is described as determining whether an adjacent area can be merged into the reference area based on either the parent station side merge upper limit number or the user side merge upper limit number in step S201, but the determination may be made taking both into consideration. In other words, the communication control unit 11 may proceed to step S105 only if the number obtained by adding 1 to the number of areas included in the reference area in step S201 does not exceed both the parent station side merge upper limit number and the user side merge upper limit number.

[0113] Next, a specific example in which the communication control unit 11 of the OLT 10 performs area merge processing in the second embodiment will be described with reference to a flowchart shown in FIG.

[0114] [Processing taking into account the parent station's merge limit] First, an example will be described in which the communication control unit 11 makes a determination in step S201 taking into consideration the parent station side merge upper limit number.

[0115] Here, similar to the first embodiment, it is assumed that RUs 30-1 to 30-9 form areas A-1 to A-9 as shown in Fig. 3. Also, it is assumed that the requested bandwidth, provisionally allocated communication rate, and communication method of areas A-1 to A-9 are in the states shown in Figs. 4 to 6, similar to the first embodiment.

[0116] Here, it is assumed that the master station side merge upper limit number held in the communication control unit 11 is "2", but the master station side merge upper limit number is not limited to this.

[0117] In this case, the communication control unit 11 performs the same processing as in the first embodiment, with area A-1 as the reference area, until merging area A-2. The communication control unit 11 in the first embodiment also merges area A-4, but since doing so would make the number of merged areas three, exceeding the parent station side merge upper limit number, it does not further merge area A-4. Therefore, the communication control unit 11 in the second embodiment generates an area (hereinafter referred to as "area A-13") in which only area A-2 is merged for area A-1, and assigns a communication rate and method.

[0118] Furthermore, when performing area merge processing with area A-4 as the reference area, the communication control unit 11 does not merge area A-7 after merging area A-5, because merging area A-7 would cause the number of areas to be merged to exceed the parent station side merge upper limit number. Therefore, the communication control unit 11 of the second embodiment generates an area (hereinafter referred to as "area A-14") in which only area A-5 is merged for area A-4, and assigns a communication rate and method.

[0119] Furthermore, in this case, in the communication control unit 11 of the second embodiment, when other areas (area A-3, area A-6, area A-7, area A-8, area A-9) are used as the reference areas, the processing results will be the same as in the first embodiment.

[0120] As described above, as a result of the communication control unit 11 of the second embodiment performing the area merge process, the areas A-1 to A-9 finally become in the state shown in FIG.

[0121] FIG. 10 is a diagram showing, in map format, the configuration of each area after the area merge process in the second embodiment.

[0122] As shown in FIG. 10, by the above-mentioned area merging process, of areas A-1 to A-9, areas A-1 and A-2 are merged into a single area A-13, and further areas A-4 and A-5 are merged into a single area A-14.

[0123] [Processing taking into account the user's merge limit] Next, an example will be described in which the communication control unit 11 makes a determination in step S201 taking into consideration the user-side merge upper limit number.

[0124] Here, similarly to the first embodiment, it is assumed that areas A-1 to A-9 as shown in FIG. 3 are formed by RUs 30-1 to 30-9.

[0125] The required bandwidths of the areas A-1 to A-9 are as shown in FIG.

[0126] FIG. 11 is a diagram showing an example of required bandwidth corresponding to areas A-1 to A-9 in the second embodiment.

[0127] Here, as shown in Fig. 11, the required bandwidths corresponding to the areas A-1 to A-9 are 2 Gbps, 1 Gbps, 12 Gbps, 1 Gbps, 2 Gbps, 3 Gbps, 1 Gbps, 110 Gbps, and 20 Gbps, respectively. In this case, the provisionally allocated communication rates and communication methods corresponding to the areas A-1 to A-9 are ultimately the same as those in Figs. 5 and 6 described above.

[0128] Here, it is assumed that the user-side merge upper limit number held in the communication control unit 11 is "4", but the user-side merge upper limit number is not limited to this.

[0129] In this case, the communication control unit 11 performs the same process as in the first embodiment until merging the areas A-1, A-2, A-4, and A-5 to generate the area A-12. At this time, since the total required bandwidth of the area A-12 is 6 Gbps, it is possible to further merge the area A-6 (required bandwidth: 3 Gbps) and the area A-7 (required bandwidth: 1 Gbps) in relation to the communication rate, but if the area A-7 is further merged into the area A-12, the user side merge upper limit number (4) will be exceeded. Therefore, the communication control unit 11 does not further merge other areas into the area A-12, and only assigns the communication rate and communication method to the area A-12 (one area obtained by merging the areas A-1, A-2, A-4, and A-5).

[0130] Furthermore, in this case, when the communication control unit 11 sets other areas (area A-3, area A-6, area A-7, area A-8, area A-9) as the reference areas, the processing results are the same as in the first embodiment.

[0131] As described above, as a result of the area merge process performed by the communication control unit 11 of the second embodiment, the areas A-1 to A-9 ultimately become in the same state as that shown in the above-mentioned Fig. 7. In Fig. 7, the areas A-1, A-2, A-4, and A-5 out of the areas A-1 to A-9 are merged into one area A-12 by the area merge process.

[0132] (B-3) Effects of the Second Embodiment According to the second embodiment, the following advantages can be achieved compared to the first embodiment.

[0133] In the communication system 1 of the second embodiment, even if the number of areas that can be merged is limited due to "OLT 10 side limitations" (parent station side merge limit number) or "user side limitations" (user side merge limit number), it is possible to reduce power consumption overall compared to the conventional method, as in the first embodiment.

[0134] Next, let us consider the power saving effect when the user side merge upper limit number is set to "2" in the second embodiment. As described above, in the second embodiment, when the user side merge upper limit number is set to "2", the result of the area merge process for areas A-1 to A-9 will be the state shown in FIG. 10 (areas A-1 and A-2 are merged to generate area A-13, and areas A-4 and A-5 are merged to generate area A-14) as described above.

[0135] FIG. 12 is a diagram showing the power saving effect in the communication system 1 according to the second embodiment.

[0136] In FIG. 12, the operation status of the ONU 20 in the above areas A-1 to A-9 in a state where the communication rate is provisionally assigned (provisional assignment state) (operation status in the state in FIG. 5) is compared with the operation status of the ONU 20 in a state where the communication rate is determined after the area merge (state after the area merge process) (operation status in the state in FIG. 10). As shown in FIG. 12, in the state after the area merge process, four ONUs 20 with a communication rate of 10 Gbps, two ONUs 20 with a communication rate of 100 Gbps, and one ONU 20 with a communication rate of 200 Gbps (total of nine ONUs 20) are operating. That is, in the state after the area merge process, the power consumption of two ONUs 20 with a communication rate of 10 Gbps is reduced. Here, it is assumed that the power consumption for each communication rate in a general ONU is the same as that in the first embodiment. In this case, as shown in FIG. 12, the total power consumption by ONUs 20-1 to 20-9 in the provisional allocation state is 45.8 W, and the total power consumption by ONUs 20-1 to 20-9 after the area merge process is 39.2 W, resulting in a reduction in power consumption of 6.6 W.

[0137] Next, the power saving effect in the second embodiment when the user side merge upper limit number is set to "4" will be considered. As described above, in the second embodiment, when the user side merge upper limit number is set to "4", the result of the area merge process for areas A-1 to A-9 will be the state shown in FIG. 7 (areas A-1, A-2, A-4, and A-5 are merged into one area A-12) as in the first embodiment. Therefore, in the second embodiment, when the user side merge upper limit number is set to "4", the power saving effect of the area merge process will be the same as in the first embodiment (similar result to FIG. 8).

[0138] (C) Other embodiments The present invention is not limited to the above-described embodiments, and may include modified embodiments such as those exemplified below.

[0139] (C-1) In each of the above embodiments, an optical communication network system 100 using a PON as a transmission path is applied as a communication network system connecting between RU 30 and DU / CU 50. However, the network configuration applied to the communication network system is not limited to PON, and various network configurations (for example, a branchable digital leased line or a bandwidth-controllable IP network) can be applied.

[0140] (C-2) In each of the above embodiments, the communication control unit 11 of the OLT 10 has been described as functioning as an allocation means for performing a provisional allocation process and an area merging means for performing an area merging process, but the allocation means and the area merging means may be mounted on a device other than the OLT 10. For example, the allocation means and the area merging means may be mounted on the DU / CU 50. [Explanation of symbols]

[0141] 1...communication system, 10...OLT, 11...communication control unit, 13...OLT concentrator, 14...10G transceiver, 15...transceiver, 16...100G transceiver, 17...transceiver, 18...200G converter, 20...ONU, 21...user side interface, 22...transceiver, 30...terminal, 60...core network, 70...splitter, 80...optical fiber, 100...optical communication network system, A...area (mesh area), TE...mobile terminal

Claims

1. a communication network system comprising: a plurality of wireless antenna devices for transmitting and receiving wireless signals to and from a mobile terminal; a signal processing device for processing transmission and reception of signals to and from the mobile terminal via the wireless antenna devices; and a communication network system for transmitting data between each of the wireless antenna devices and the signal processing devices, the communication network system having a slave station communication device connected to each of the wireless antenna devices, a master station communication device connected to the signal processing device, and a transmission path connecting the master station communication device to each of the slave station communication devices, an allocation means for allocating a communication rate and a communication method to an area corresponding to each of the wireless antenna devices; an area merging means for performing an area merging process of selecting one of the areas as a reference area, and merging the reference area and the adjacent area into one merged area and assigning a communication rate and a communication method to the merged area when the communication rate and the communication method are the same in the reference area and an adjacent area adjacent to the reference area, and the sum of the required bandwidth of the reference area and the required bandwidth of the adjacent area is equal to or less than the communication rate; A communication system comprising:

2. The communication system according to claim 1 , wherein the area merging unit further performs the area merging process using the merged area generated by the area merging process as the reference area.

3. The communication system described in claim 2, characterized in that the area merging means recognizes the upper limit number of the areas that can be merged simultaneously to each of the wireless antenna devices as a user side merge upper limit number, and performs the area merging process so that the number of the areas included in the merging area does not exceed the user side merge upper limit number of the area that is representative of the merging area.

4. The communication system according to claim 2, characterized in that the area merge means recognizes an upper limit number of the areas that can be merged simultaneously based on the specifications of the parent station communication device as a parent station side merge upper limit number, and performs the area merge processing so that the number of the areas included in the merge area does not exceed the parent station side merge upper limit number.

5. 3. The communication system according to claim 2, wherein the area merging unit assigns the same communication rate and communication method to the merging area as to the reference area.

6. 2. The communication system according to claim 1, wherein the transmission path is configured by a PON.

7. A communication control method performed by a communication system including a plurality of wireless antenna devices for transmitting and receiving wireless signals to and from a mobile terminal, a signal processing device for processing transmission and reception of signals to and from the mobile terminal via the wireless antenna devices, and a communication network system for transmitting data between each of the wireless antenna devices and the signal processing devices, the communication network system having a slave station communication device connected to each of the wireless antenna devices, a master station communication device connected to the signal processing device, and a transmission path for connecting the master station communication device to each of the slave station communication devices, comprising: The communication system includes an allocation means and an area merging means, the allocation means allocates a communication rate and a communication method to an area corresponding to each of the wireless antenna devices; The area merging means selects one of the areas as a reference area, and when the communication rate and communication method of the reference area and an adjacent area adjacent to the reference area are the same and the sum of the required bandwidth of the reference area and the required bandwidth of the adjacent area is equal to or less than the communication rate, performs area merging processing to merge the reference area and the adjacent area into one merged area and assign a communication rate and a communication method to the merged area. A communication control method comprising:

8. In a communication network system for transmitting data between a plurality of wireless antenna devices which transmit and receive wireless signals to and from a mobile terminal, and a signal processing device which processes transmission and reception of signals to and from the mobile terminal via the wireless antenna devices, a master station communication device connects the signal processing device via a transmission path to slave station communication devices which are connected to the respective wireless antenna devices, an allocation means for allocating a communication rate and a communication method to an area corresponding to each of the wireless antenna devices; an area merging means for performing an area merging process of selecting one of the areas as a reference area, and merging the reference area and the adjacent area into one merged area and assigning a communication rate and a communication method to the merged area when the communication rate and the communication method are the same in the reference area and an adjacent area adjacent to the reference area, and the sum of the required bandwidth of the reference area and the required bandwidth of the adjacent area is equal to or less than the communication rate; A master station communication device comprising:

Images