Patent Application
20180014212
The present invention relates to a satellite communication device, a management device, and a monitoring method in a monitoring system that monitors a ground radio communication system by using satellite communication.
In recent years, increased attention has been focused on a communication means to accurately confirm the safety of individuals and transmit information if a major disaster has occurred, such as an earthquake or a tsunami. However, in a ground radio communication system for mobile phones and other devices which have become widespread among ordinarily users, communication facilities, that is, a communication infrastructure is monitored by mainly using a wired line such as a public telecommunication network. Therefore, there is a problem in that individual facilities cannot always be monitored accurately. For example, in the case of a break in a wired line due to the occurrence of a major disaster, a mobile base station connected to the wired line cannot be monitored. Further, if a concentrator, such as a relay device that concentrates mobile base stations, stops functioning due to a fault, a power outage, or other problems, then the mobile base stations connected to the concentrator cannot be monitored.
As a method for solving the problems as described above, Patent Literature 1 has disclosed a technique, in which a transmission-path control server collects base station information including an operational status from each base station by using satellite communication, identifies a base station that is adjacent to, and capable of communicating with, an isolated base station that is incapable of communicating with a base-station control device that is a higher-level device, and establishes a radio connection between the base stations as an emergency transmission path, in order to bring the isolated base station back into a state of being capable of communication. In the disclosed technique, even in the event of irregularities, it is still possible to continuously provide communication service.
Japanese Patent Application Laid-open No. 2012-160933
However, the technique disclosed in Patent Literature 1 has a problem in that after the control server has identified an isolated base station that is incapable of communicating with the base-station control device by using satellite communication, if there is not an adjacent base station that is capable of communicating with the base-station control device, then the control server cannot continue or resume communication service. Further, in the technique disclosed in Patent Literature 1, in a state in which the satellite channel is busy due to the congestion caused by too many simultaneous access requests at the time of a disaster, there is a problem in that the control server may not efficiently collect information used for identifying an isolated base station, that is, it may be difficult to monitor the base stations.
The present invention has been achieved to solve the above problems, and an object of the present invention is to provide a communication device that can monitor a ground radio communication system by using satellite communication with high reliability, while minimizing heavy communication traffic and congestion of a satellite channel.
In order to solve the problems and achieve the object, according to an aspect of the present invention, there is provided a satellite communication device including: a first communication unit to receive monitoring information from a communication device, which is a result of monitoring a device state of the communication device; a second communication unit to perform radio communication with a satellite; a storage device to store therein transfer information that indicates conditions for selecting the monitoring information to be transferred to the second communication unit from among the monitoring information; and a processing unit to select the monitoring information to be transferred to the second communication unit from among the monitoring information on a basis of the transfer information, and to transfer the selected monitoring information to the second communication unit.
The communication system according to the present invention has an effect where it is possible to monitor a ground radio communication system by using satellite communication with high reliability, while minimizing heavy communication traffic and congestion of a satellite channel.
A satellite communication device, a management device, a monitoring system, and a monitoring method according to an embodiment of the present invention will be described in detail below with reference to the accompanying drawings. The present invention is not limited to the embodiment.
A monitoring system 40 according to the present embodiment includes a management device 15, satellite communication terminals 31a, 31b, and 31c, each of which is a satellite communication device according to the present invention, and a core network device 13. The ground radio system that is a target to be monitored by the monitoring system 40 according to the present embodiment includes mobile base stations 10a, 10b, and 10c, each of which is a communication device. That is, the mobile base stations 10a, 10b, and 10c constitute the ground radio system. It is possible that the ground radio system that is a target to be monitored by the management device 15 includes devices other than the mobile base stations 10a, 10b, and 10c, and also includes the core network device 13, a relay station 16, and other devices. However, in this example, monitoring of the mobile base stations 10a, 10b, and 10c is described below. The mobile base stations 10a, 10b, and 10c are connected to the core network device 13 and other mobile base stations 10a, 10b, and 10c through a wired line 14. The relay station 16 relays communication between the mobile base stations 10a and 10b, and the core network device 13 through the wired line 14. Further, the satellite communication terminal 31a is connected to the mobile base station 10a through the wired line 14, and is located at a position at a short distance from the mobile base station 10a. The position at a short distance indicates, for example, that the satellite communication terminal 31a is distanced from the mobile base station 10a by about several meters or less. It is also possible that the satellite communication terminal 31a and the mobile base station 10a are integrated into a single device. Similarly, the mobile base station 10c is connected to the satellite communication terminal 31c through the wired line 14. The satellite communication terminal 31c is located at a position at a short distance from the mobile base station 10c.
Service areas 11a, 11b, and 11c in
In the following descriptions, when the mobile base stations 10a, 10b, and 10c are described without being distinguished from each other, they are appropriately referred to as a “mobile base station 10”. Similarly, when the service areas 11a, 11b, and 11c are described without being distinguished from each other, they are appropriately referred to as a “service area 11”. When the mobile radio signals 12a, 12b, and 12c are described without being distinguished from each other, they are appropriately referred to as a “mobile radio signal 12”. When the mobile devices 30a and 30c are described without being distinguished from each other, they are appropriately referred to as a “mobile device 30”. When the satellite communication terminals 31a, 31b, and 31c are described without being distinguished from each other, they are appropriately referred to as a “satellite communication terminal 31”. While
The core network device 13 is a higher-level device that controls a plurality of mobile base stations 10, and executes a call control, an authentication process, and the like between the mobile base station 10 and the mobile device 30. The core network device 13 also has a function as a relay device that relays communication between the mobile base station 10 and the management device 15. The mobile base station 10 and the core network device 13 are connected through the wired line 14. Devices such as a router, the relay station 16, and an optical line, are connected to the wired line 14. The wired line 14, and the devices connected to the wired line 14, constitute the IF (Internet Protocol) network. An example is described below, in which communication through the wired line 14 uses the IP as a communication protocol. However, the communication protocol used in communication through the wired line 14 is not limited thereto.
In the following descriptions, each device that constitutes the ground radio communication system is also referred to as a “communication infrastructure device”, and the ground radio communication system is also referred to as a “communication infrastructure”. The management device 15 manages each device that constitutes the ground radio communication system, such as the mobile base station 10 and the core network device 13. That is, the device 15 manages each communication infrastructure device. Specifically, the management device 15 has a function of setting the operation of the mobile base station 10, such as a frequency setting to the mobile base station 10 through the wired line 14, a function of collecting monitoring information that is the result of monitoring the device state of each individual device that constitutes the ground radio communication system, a function of displaying alarm information such as fault information, and other functions. The monitoring information in the present embodiment is described later. It is sufficient that a single management device 15 is provided within the monitoring system 40. However, it is also possible that there are a plurality of management devices 15 within the monitoring system 40. For example, it is possible that the functions of the management device 15 are divided and allocated to two separate management devices, which are provided respectively to process the monitoring information of a communication infrastructure device through the wired line 14, and to process the monitoring information of a communication infrastructure device using a satellite channel.
In the monitoring system 40 according to the present embodiment, the management device 15 collects monitoring information from the mobile base station 10 and the core network device 13 through the wired line 14. The monitoring information indicates the result of monitoring the device state of each individual device. In addition to this configuration, in the monitoring system 40 according to the present embodiment, the management device 15 collects the monitoring information of the mobile base station 10 by using a satellite channel.
As illustrated in
As illustrated in
The device management unit 101 monitors the device state of the mobile base station 10. Specifically, the device management unit 101 monitors, for example, one or more of a hardware state, a wired connection state, a radio communication state, and a power supply state of the mobile base station 10. The hardware state indicates that either irregularities, that is, a fault has occurred in the mobile base station 10, or the mobile base station 10 operates properly. For example, one or more of the constituent elements of the mobile base station 10 are designed to detect a fault in any of the constituent elements, and output an alarm signal. Upon detecting this alarm signal, the device management unit 101 determines that a fault has occurred in the mobile base station 10. An irregular hardware state of the mobile base station 10 indicates that a flow of overcurrent is detected, which results in the device internal temperature becoming a predetermined temperature or higher. Further, in the case where the device is configured by a plurality of substrates, an irregular hardware state indicates that there is no response from any of the substrates when the alive monitoring is performed between the substrates. The method for the device management unit 101 to detect a fault in the mobile base station 10 is not limited thereto. It is possible that the device management unit 101 uses any method as long as the method can detect a fault within the mobile base station 10. The wired connection state indicates whether a communication path between the mobile base station 10 and the core network device 13 is properly established through the wired I/F unit 100. An example of the bath establishment procedure is described later. Furthermore, the mobile base station 10 detects an irregular wired connection state when the Ethernet® connection link is down, or when the alive monitoring is performed using “HEARTBEAT” between the mobile base station 10 and the core network device 13 as defined in the SCTP (Stream Control Transmission Protocol), and then the mobile base station 10 does not receive any response from a counterpart device for a given period of time (or a given number of times). The radio communication state indicates a state in which the mobile base station 10 has detected the radio communication state to be either normal or abnormal. The mobile base station 10 detects an irregular radio communication state, for example, when it detects that a radio wave cannot be transmitted due to irregularities of a transmission amplifier, or when the mobile base station 10 has detected upload data, but cannot receive it for a long period of time, or when the mobile base station 10 cannot maintain the frequency accuracy that satisfies the radio standards due to clock irregularities. The mobile base station 10 detects an irregular power supply state when the voltage/current (power) is decreased, or when the temperature in the power device is increased irregularly.
The antenna unit 106 transmits and receives the mobile radio signal 12 to and from the mobile device 30. In the following descriptions, the antenna unit is abbreviated as an “ANT unit” in the diagrams. The wireless I/F unit 102 performs a process of transmitting and receiving the mobile radio signal 12 in conformity with the communication standards of the mobile base station 10 and mobile phones. The radio control unit 103 performs a process of establishing a radio connection with the mobile device 30. The power unit 104 has a function of supplying power, provided from an external power supply such as a system power supply, to each unit within the ground base station 10. The power unit 104 is also capable of supplying power by using the power, provided from a power generator such as a photovoltaic power-generation device, at the time of a power outage in the external power supply. The storage device 105 stores therein the internal information needed for operating the mobile base station 10, and other information. The internal information needed for operating the mobile base station 10 includes operational information received from the management device 15 in a processing procedure at the startup described later. The internal information needed for operating the mobile base station 10 is information of a frequency in use (a band), transmission power, radio control information (a retransmission parameter, the number of times of retransmission, a channel configuration, and parameters that are not dynamically variable), the IP address (fixed assignment) of the mobile base station 10 itself and its peripheral devices, the IP address acquisition method (automatic assignment), or other information.
As illustrated in
The power supply unit 204 is configured by a power unit 205 and a battery unit 208. The power unit 205 supplies power, provided from an external power supply, to each unit within the satellite communication terminal 31. The battery unit 206 is a battery to be charged while the power is supplied from the external power supply. If a power supply from the external power supply is stopped due to a power outage or the like, the battery unit 206 supplies the accumulated power to each unit within the satellite communication terminal 31. The storage device 207 stores therein the internal information needed for the operation of the satellite communication terminal 31, and the information processing policy information. Examples of the internal information needed for the operation of the satellite communication terminal 31 include a frequency to be used for communication with the satellite 20, which is obtained in the process of establishing communication with the satellite 20.
The wired I/F unit 300 is a communication unit that receives monitoring information from the mobile base station 10 through the wired line 14, which is the result of monitoring the device state of the mobile base station 10. The monitoring unit 301 updates the device-state information that indicates the device state of the mobile base station 10 on the basis of the monitoring information received by the wired I/F unit 300. As described later, when the management device 15 cannot receive monitoring information for a given period of time or longer, the monitoring unit 301 generates a monitoring-information setting request that is control information for configuring the settings for a satellite communication device such that the monitoring information is transmitted to the management device 15 itself through the satellite channel via the satellite communication terminal 31 being connected to the mobile base station 10. The monitoring unit 301 updates the device-state information on the basis of the monitoring information received through the satellite communication terminal 31 and the satellite channel.
The satellite base station 23 includes a wired I/F unit 500, a device management unit 501, a wireless I/F unit 502, a radio control unit 503, a power unit 504, a storage device 505, and an antenna unit 506. The wired I/F unit 500 performs a transmission and reception process in conformity with the IP between the satellite base station 23, and the core network device 13 and the management device 15, through the wired line 14.
The device management unit 501 monitors the device state of the satellite base station 23. The antenna unit 506 transmits and receives the satellite radio signal 22a to and from the satellite 20. The wireless I/F unit 502 performs a process of transmitting and receiving the satellite radio signal 22a to and from the satellite 20. The radio control unit 503 performs a process of establishing a radio connection with the satellite 20. The power unit 504 supplies power, provided from an external power supply such as a system power supply, to each unit within the satellite base station 23. The storage device 505 stores therein the internal information needed for operating the satellite base station 23, and other information. The internal information needed for operating the satellite base station 23 includes operational information received from the management device 15 in a processing procedure at the startup described later. The internal information needed for operating the satellite base station 23 is satellite beam orientation information, information of a frequency in use (a band allocated to the beam), transmission power, radio control information (a retransmission parameter, the number of times of retransmission, and parameters that are not dynamically variable), the IP address (fixed assignment) of the satellite base station 23 itself and its peripheral devices, the IP address acquisition method (automatic assignment), or other information.
Next, the hardware configuration of the mobile base station 10, the satellite communication terminal 31, the management device 15, and the satellite base station 23, is described. Each constituent unit of the mobile base station 10 illustrated in
It is possible that the processing circuit that implements the device management unit 101, and the processing circuit that implements the radio control unit 103, are either dedicated hardware or a control circuit that includes a memory, and a CPU (Central Processing Unit, which is also referred to as a “processing device”, “computation device”, a “microprocessor”, a “microcomputer” a “processor”, or a DSP (Digital Signal Processor)) that executes a program stored in the memory. Examples of the memory include a nonvolatile or volatile semiconductor memory, such as a RAM (Random Access Memory), a ROM (Read Only Memory), a flash memory, an EPROM (Erasable Programmable Read Only Memory), or an EEPROM (Electrically Erasable Programmable Read Only Memory), and also include a magnetic disk, a flexible disk, an optical disk, a compact disk, a minidisk, and a DVD (Digital Versatile Disk).
In the case where each of the device management unit 101 and the radio control unit 103 is implemented by dedicated hardware, these units are, for example, a single circuit, a combined circuit, a programmed processor, a parallel-programmed processor, an ASIC (Application Specific Integrated Circuit), an FPGA (Field Programmable Gate Array), or a combination thereof.
In the case where each of the device management unit 101 and the radio control unit 103 is implemented by a control circuit that includes a CPU, this control circuit is, for example, a control circuit 400 that is configured as illustrated in
Each constituent unit of the satellite communication terminal 31 illustrated in
It is possible that the processing circuit that implements the monitoring-information processing unit 201, and the processing circuit that implements the radio control unit 203, are either dedicated hardware or a control circuit including a memory, and a CPU that executes a program stored in the memory. In the case where the monitoring-information processing unit 201 is implemented by dedicated hardware, this unit is, for example, a single circuit, a combined circuit, a programmed processor, a parallel-programmed processor, an ASIC, an FPGA, or a combination thereof.
In the case where each of the monitoring-information processing unit 201 and the radio control unit 203 is implemented by a control circuit that includes a CPU, this control circuit is, for example, the control circuit 400 that is configured as illustrated in
Each constituent unit of the management device 15 illustrated in
It is possible that the processing circuit that implements the monitoring unit 301 is either dedicated hardware or a control circuit including a memory, and a CPU that executes a program stored in the memory. In the case where the monitoring unit 301 is implemented by dedicated hardware, this unit is, for example, a single circuit, a combined circuit, a programmed processor, a parallel-programmed processor, an ASIC, an FPGA, or a combination thereof.
In the case where the monitoring unit 301 is implemented by a control circuit that includes a CPU, this control circuit is, for example, the control circuit 400 that is configured as illustrated in
Each constituent unit of the satellite base station 23 illustrated in FIG. can be implemented as hardware such as an electronic circuit or the like. The ANT unit 506 is configured by an antenna, and a processing circuit that is an electronic circuit such as a frequency conversion circuit, an amplifier, or an analog-digital converter. Each of the wired I/F unit 500 and the wireless I/F unit 502 is a communication interface circuit. The radio control unit 503 is a processing circuit that executes a radio control in conformity with the communication standards in the satellite communication system. The power unit 504 is a power supply circuit that supplies power. The storage device 505 is a memory. The device management unit 501 is a processing circuit that is an electronic circuit that performs a device management process.
It is possible that the processing circuit that implements the device management unit 501, and the processing circuit that implements the radio control unit 503, are either dedicated hardware or a control circuit including a memory, and a CPU that executes a program stored in the memory. In the case where the device management unit 501 is implemented by dedicated hardware, this unit is, for example, a single circuit, a combined circuit, a programmed processor, a parallel-programmed processor, an ASIC, an FPGA, or a combination thereof.
In the case where each of the device management unit 501 and the radio control unit 503 is implemented by a control circuit that includes a CPU, this control circuit is, for example, the control circuit 400 that is configured as illustrated in
Next, the operation of the monitoring system 40 in the present embodiment is described. First, there is described a procedure, which is used from when the mobile base station 10 and the satellite base station 23 are started-up, then a path is established between the mobile base station 10 and the core network device 13, and then service of the ground radio communication system is started, to when the management device 15 starts monitoring the communication infrastructure. That is, a processing procedure at the startup of the mobile base station 10 and the satellite base station 23 is described.
Upon receiving an operational-information obtaining request from the mobile base station 10 and the satellite base station 23, the management device 15 reads operational information for the mobile base station 10, and operational information for the satellite base station 23, which are stored in the storage device 304, and then distributes, that is, transmits the corresponding operational information to the mobile base station 10 and to the satellite base station 23 (Step S2). Specifically, in the management device 15, upon receiving an operational-information obtaining request from the mobile base station 10 through the wired I/F unit 300, the monitoring unit 301 reads operational information for the mobile base station 10 from the storage device 304, and transmits the read operational information to the mobile base station 10 through the wired I/F unit 300. In addition, in the management device 15, upon receiving an operational-information obtaining request from the satellite base station 23 through the wired I/F unit 300, the monitoring unit 301 reads operational information for the satellite base station 23 from the storage device 304, and transmits the read operational information to the satellite base station 23 through the wired I/F unit 300.
The operational information be distributed by the management device 15 to the mobile base station 10 includes frequency information that indicates a frequency band to be used for transmitting and receiving the mobile radio signal 12, transmission power information that indicates transmission power when the mobile base station 10 transmits the mobile radio signal 12, connection information for being connected to the core network device 13 that is a higher-level device that monitors the path, and other information. Examples of the connection information for being connected to the core network device 13 include IP address information of the core network device 13. The operational information, to be distributed by the management device 15 to the satellite base station 23, includes setting information associated with the satellite 20, which is used for the management system in the present embodiment to monitor the ground radio communication system. Examples of this setting information include beam orientation in the satellite 20, frequency assignment information that indicates a frequency to be used to each beam by the satellite 20, power allocation information that indicates transmission power for each beam, and identification information of a beam and the mobile base station 10 within the beam irradiated area. Further, the operational information, to be distributed by the management device 15 to the satellite base station 23, includes connection information for being connected to the core network device 13, and other information.
In the mobile base station 10, the device management unit 101 uses the information included in the received operational information to set up the wireless I/F unit 102 and other units, in order to start mobile phone service. In the satellite base station 23, the device management unit 501 transmits the setting information included in the received operational information as the satellite radio signal 22a to the satellite 20 through the wireless I/F unit 502 and the antenna unit 506. Satellite communication service is thereby started.
Upon completion of the settings to start mobile phone service, the device management unit 101 in the mobile base station 10 tarts path establishment in order to monitor the communication path between the mobile base station 10 and the core network device 13 (Step S3). The path establishment is performed in conformity with the path monitoring protocol. There are typical path monitoring protocols such as the SCTP (Stream Control Transmission Protocol) that is a transport layer protocol. However, the path monitoring protocol is not limited thereto. The device management unit 101 in the mobile base station 10 generates a path establishment request that requests the start of path establishment, and transmits the request to the core network device 13 through the wired I/F unit 100 (Step S4). The path establishment request includes a connection-destination IP address of the core network device 13, which is needed for IP transmission between the mobile base station 10 and the core network device 13. In the case where a plurality of wired I/Fs are used to use a plurality of IP transmission paths, the path establishment request includes plural pieces of IP address information. The core network device 13 transmits to the mobile base station 10 a path establishment response that is a response to the path establishment request (Step S5). The path establishment is completed through the process described above.
Upon completion of the path establishment, the device management unit 101 in the mobile base station 10, and the core network device 13 start path monitoring (Steps S6 and S7). As described above, as a path monitoring method, the SCTP can be used, for example. When the device management unit 101 in the mobile base station 10, and the core network device 13 have started path monitoring, the device management unit 101 in the mobile base station 10 transmits a path monitoring request to the core network device 13 (Step S8). The core network device 13, having received the path monitoring request, returns a path monitoring response (Step S9). Due to this operation, a communication path is established between the mobile base station 10 and the core network device 13 (Step S10).
The device management unit 101 in the mobile base station 10 transmits a device-startup completion notification for notifying completion of the device startup to the management device 15 through the wired I/F unit 100 (Step S11). The monitoring unit 301 in the management device 15 transmits a device-monitoring start request that requests the start of monitoring the device state of the mobile base station 10 through the wired I/F unit 300 to the mobile base station 10 (Step S12). In the mobile base station 10, upon receiving the device-monitoring start request through the wired I/F unit 100, the device management unit 101 generates a device-monitoring start response to the management device 15, which is a response that allows the mobile base station 10 itself to be a target to be monitored, and transmits this response to the management device 15 through the wired I/F unit 100 (Step S13). Thereafter, the device management unit 101 starts monitoring its own device, that is, monitoring the device state (Step S14). The device management unit 101 performs the device monitoring, that is, monitors the device state, to generate monitoring information that is the result of monitoring the device state. The monitoring information is information that individually indicates the hardware state, the wired connection state, the radio communication state, the power supply state which are described previously, and other states. That is, the monitoring information includes hardware information that indicates the hardware state, wired connection information that indicates the wired connection state, radio communication information that indicates the radio communication state, power supply information that indicates the power supply state, and other information.
As a device monitoring method, the SNMP (Simple Network Management Protocol), which uses the management information referred to as a “MIB (Management Information Base)”, the ZIP (Customer Premises Equipment WAN Management Protocol), designed to remotely manage customer premises equipment, and standardized by Broadband Forum, or other protocols can be used. However, the device monitoring method is not limited thereto.
With reference to
In addition to this configuration, in the present embodiment, the mobile base station 10 transmits the monitoring information also to the satellite communication terminal 31 through the wired I/F unit 100. It is also possible that the satellite communication terminal 31 has a function of monitoring the information to be transmitted from the wired I/F unit 100 in the mobile base station 10 through the wired line 14 to the core network device 13. Due to this configuration, the mobile base station 10 can transmit the monitoring information to the management device 15 via the satellite communication terminal 31, the satellite 20, the satellite base station 23, and the core network device 13, that is, via the satellite channel. A path, extending through the mobile base station 10, the wired line 14, the core network device 13, and the management device 15, is appropriately referred to as a “wired path”. Meanwhile, when the mobile base station 10 is capable of transmitting monitoring information to the management device 15 without via the satellite channel and still transmits monitoring information to the management device 15 via the satellite channel, then the satellite channel resource not used efficiently. Therefore, in the present embodiment, the satellite communication terminal 51 uses the monitoring-information processing policy information to determine the processing to be performed on an IP packet received from the mobile base station 10 according to the details of the IP packet. With this monitoring-information processing policy information, unnecessary monitoring information is determined not to be transferred through the satellite channel. Accordingly, if a fault has occurred on the wired path between the mobile base station 10 and the management device 15 due to disaster or the like, the management device 15 can obtain the monitoring information from the mobile base station 10 with minimal use of the satellite channel resource.
As illustrated in
In the column “processing number 1” in
“OID (ObjectID)” illustrated in
When the satellite communication terminal receives an IP packet from the mobile base station 10, “transfer” in the monitoring-information processing policy information illustrated in
Next, there is described a transfer process using the monitoring-information processing policy information in the satellite communication terminal 31, that is, a process of determining the monitoring-information processing policy. As illustrated in
As a result of the determination at Step S22, when there is a processing number in which the port number matches the condition (YES at Step S22), the monitoring-information processing unit 201 verifies the setting information of the applicable processing number within the monitoring-information processing policy information, to determine whether the conditions match each other (Step S23). Specifically, to each setting information of the applicable processing number within the monitoring-information processing policy information, the monitoring-information processing unit 201 determines whether the value of an item, corresponding to the setting information within the received IP packet, corresponds with the value indicated by the setting information within the monitoring-information processing policy information. Subsequently, when the value of an item, corresponding to the setting information within the received IP packet, corresponds with the value indicated by the setting information of the applicable processing number within the monitoring-information processing policy information, then the monitoring-information processing unit 201 determines these conditions match each other.
As a result of the determination at Step S23, when the conditions match each other (YES at Step S23), the monitoring-information processing unit 201 performs a process registered in the corresponding processing number within the monitoring-information processing policy information (Step S24), and then ends the process. As a result of the determination at Step S22, when there is no processing number that meets the condition (NO at Step S22), the monitoring-information processing unit 201 determines whether retrieval of all the pieces of registered information within the monitoring-information processing policy information has been completed, that is, retrieval of all the processing numbers within the monitoring-information processing policy information has been completed (Step S25). When retrieval of all the pieces of registered information within the monitoring-information processing policy information has been completed (YES at Step S25), the monitoring-information processing unit 201 discards the IP packet (Step S26), and then ends the process. As a result of the determination at Step S23, when the conditions do not match each other (NO at Step S23), the process flow advances to Step S25. When the determination at Step S25 is NO (NO at Step S25), the process flow returns to Step S22. There has been described the process in the case when the satellite communication terminal 31 receives an IP packet from the mobile base station 10 through the wired I/F unit 200. However, even when the satellite communication terminal 31 receives an IP packet from the management device 15 through the wireless I/F unit 202, the process of determining the monitoring-information processing policy is still performed in the same manner as illustrated in
Next, the process of determining the monitoring-information processing policy in the present embodiment is described by using a specific example of the IP packet.
In this example, it is assumed that the mobile base station 10 uses the SNMP as a device monitoring method to transmit an SNMP Trap packet that is an SNMP packet, in which the type 601 within the SNMP packet illustrated in
An IP packet, designed to register, update, or delete the monitoring-information processing policy information to be transmitted from the management device 15 to the satellite communication terminal 31 itself, is not targeted for the determination based on the monitoring-information processing policy information. Therefore, regardless of the registered details in the monitoring-information processing policy information, the satellite communication terminal 31 performs an operation instructed by the IP packet, such as registration, update, or deletion of the monitoring-information processing policy information transmitted to the satellite communication terminal 31 itself.
The mobile base station 10 receives a setting command from the management device 15 through a wired path or a path using the satellite channel, where the setting command instructs to configure the settings for the monitoring information to be transmitted to the management device 15. For example, this setting command is issued by following the SNMP. For example, the management device 15 can configure the settings of the mobile base station 10 so as to periodically transmit monitoring information by using an SNMP packet. Upon receiving an SUMP packet designed to set periodic monitoring-information transmission, the mobile base station 10 periodically generates and transmits monitoring information regardless of a change in the monitoring information, that is, regardless of the presence or absence of irregularities.
When periodic monitoring-information transmission has not been set (NO at Step S101), the device management unit 101 determines whether the device state has changed (Step S105). As described previously, the device state is, for example, the hardware state, the wired connection state, the radio communication state, or the power supply state. In the case where the device state is constituted with a plurality of state-types as described above, when one or more of the state-types have changed, then the device management unit 101 determines that the device state has changed. Generally, a change in the device state indicates that there is a change from the normal state, that is, the device state is abnormal.
When the device state has changed (YES at Step S105), the device management unit 101 generates and outputs a notification of a change in the monitoring information to the wired I/F unit 100 (Step S106), and then the process flow returns to Step S101. The wired I/F unit 100 transmits the notification of a change in the monitoring information to the management device 15 and the satellite communication terminal 31 through the wired line 14. As a notification of a change in the monitoring information, the SNMP Trap packet described previously can be used, for example. When the device state has not changed (NO at Step S105), the process flow returns to Step S101. At Step S102, when a given period of time has not elapsed yet since the last monitoring-information transmission (NO at Step S102), the device management unit 101 determines whether the device state has changed (Step S104). At Step S104, when the device state has changed (YES at Step S104), the process flow advances to Step S106. At Step S104, when the device state has not changed (NO at Step S104), the process flow returns to Step S102.
For example, there is a case where the monitoring unit 301 in the management device 15 cannot receive periodic monitoring information through a wired path from the mobile base station 10, which has been instructed to set the periodic monitoring-information transmission, for a given period of time or longer. In that case, the monitoring unit 301 determines that there is a fault on the wired path, and changes the monitoring information settings so as to obtain the monitoring information through the satellite channel. In the initial state of the monitoring-information processing policy information, transfer of the periodic monitoring information is not set.
In the storage device 304 of the management device 15, the IP address of the satellite communication terminal 31 is stored in advance. The monitoring unit 301 stores this IF address in the monitoring-information setting request as its destination. In this monitoring-information setting request, an identifier of the satellite communication terminal as a destination, and an identifier of the mobile base station 10 corresponding to this satellite communication terminal 31, are also stored. In the satellite base station 23, upon receiving the monitoring-information setting request via the wired I/F unit 500, the device management unit 501 determines a beam of the satellite 20 in the area where the satellite communication terminal 31 is present, which is associated with the destination of the monitoring-information setting request. The radio control unit 503 establishes a radio connection with the satellite communication terminal 31, generates a control signal including the monitoring-information setting request, and transmits the control signal to the satellite 20 via the wireless I/F unit 502 and the ANT unit 506. The satellite 20 transmits the monitoring-information setting request by using a beam designated by the control signal. In this manner, the satellite communication terminal 31 receives the monitoring-information setting request. Upon receiving the monitoring-information setting request, the satellite communication terminal 31 changes the monitoring-information processing policy information in the storage device 207 on the basis of the received monitoring-information setting request. In this example, it is assumed that the monitoring information settings have been changed so as to transfer a notification of a change in the monitoring information.
Thereafter, upon receiving the notification of a change in the monitoring information via the satellite channel, the monitoring unit 301 in the management device 15 updates the device-state information having been stored in the storage device 304, on the basis of the received notification of a change in the monitoring information (Step S113), and then ends the process.
Next, a process of obtaining monitoring information from the mobile base station 10 by the management device 15 is described.
Upon detecting a change in the device state (Step S39), the device management unit 101 in the mobile base station 10 generates and transmits a notification of a change in the monitoring information to the satellite communication terminal 31 (Step S40). The device management unit 101 in the mobile base station 10 performs the process of determining the monitoring-information processing policy. As a result of the process of determining the monitoring-information processing policy, when there are applicable settings in the monitoring-information processing policy information, and the processing details specify “transfer”, then the monitoring-information processing unit 201 in the satellite communication terminal 31 transfers a notification of a change in the monitoring information to the management device 15 via the satellite channel (Step S42). As result of the process of determining the monitoring-information processing policy, when there are applicable settings in the monitoring-information processing policy information, and the processing details specify “random transfer”, then the monitoring-information processing unit 201 in the satellite communication terminal 31 calculates a transfer delay time for delaying transfer of the received notification of a change in the monitoring information (Step S43), and starts an internal or external timer to measure an elapsed time with the timer (Step S44). The time required for the expiry of this timer is set as the calculated transfer delay time described above. “Random transfer” as one of the processing details is a process of transferring monitoring information that satisfies the corresponding conditions with a delay. In this process of transferring the monitoring information with a delay, the delay time that is a time for delaying the transfer is calculated so as to be divided to each satellite communication terminal 31, that is, so as to differ between the satellite communication terminals 31 as much as possible.
After the expiry of the timer, that is, after the transfer delay time has elapsed, the monitoring-information processing unit 201 transfers a notification of a change in the monitoring information to the management device 15 via the satellite channel (Step S45). The transfer delay time for random transfer is calculated such that the value of transfer delay time differs between a plurality of satellite communication terminals 31 in order to avoid too many simultaneous access requests to the satellite 20 if the device state of the satellite communication terminals 31 changes simultaneously in the event of a disaster.
Transfer delay time=terminal-specific identifier mod divided-transfer time (1)
As a terminal-specific identifier, a characteristic value, which differs between the satellite communication terminals, is used, such as an IMSI (International Mobile Subscriber Identity) stored in the USIM (Universal Subscriber Identity Module) inserted into the satellite communication terminal 31, or an IMEI (International Mobile Equipment Identity) that is the individual number of the satellite communication terminal 31.
When a disaster has occurred, the monitoring-information processing unit 201 calculates a transfer delay time on the basis of this terminal-specific identifier and the divided-transfer time. This makes it possible to calculate a different transfer delay time for each satellite communication terminal 31. That is, the time at which information is transferred from each satellite communication terminal 31 to the satellite channel can be divided. A delay time #1, a delay time #2, a delay time #3, and a delay time #4 in
Referring back to the descriptions in
The monitoring unit 301 in the management device 15 receives an input of the information designed to change the monitoring-information processing policy information from the input unit 305. On the basis of the input information, the monitoring unit 301 performs a monitoring-information updating process, that is, a process of updating the monitoring-information processing policy information to be set in the satellite communication terminal 31 (Step S55). It is possible that at this time, an individual item of the setting details in the monitoring-information processing policy information is either manually input from the input unit 305, or selected from among the setting details registered in the storage device 304 in advance, and then input by the input unit 305. After execution of the monitoring-information updating process, the management device 15 transmits a monitoring-information setting request that is a request for updating the monitoring-information processing policy information to the satellite communication terminal 31 through the wired I/F unit 300 (Step S56). The monitoring-information setting request includes information that specifies which details are to be changed, for example, the processing number, and the items to be changed, that is, the protocol type, the set information #0, the set information #1, and the like. The request also includes the changed details. Furthermore, not only a change in the monitoring information, but also registration of an additional item, processing number, and the like, and deletion of the item and the processing number, can be instructed by a monitoring-information setting request. At this time, it is possible that the monitoring unit 301 updates the monitoring-information processing policy information either individually to each satellite communication terminal 31, or simultaneously to a plurality of satellite communication terminals 31.
The monitoring-information processing unit 201 in the satellite communication terminal 31, having received the monitoring-information setting request, updates the details of the monitoring-information processing policy information stored in the storage device 207 to the details designated by the monitoring-information setting request (Step S57).
Therefore, the monitoring unit 301 in the management device 15 calculates a divided-transfer time on the basis of the number of communication infrastructure devices from which the management device 15 is incapable of obtaining monitoring information (Step S73). It is also possible that the relation between the number of communication infrastructure devices and the divided-transfer time is stored as a table in the storage device 304 of the management device 15, and then the monitoring unit 301 references the table to derive a divided-transfer time corresponding to the number of communication infrastructure devices from which the management device 15 is incapable of obtaining monitoring information. It is further possible that the processing time per communication infrastructure device is defined in order to set the total processing time for the number of communication infrastructure devices, from which the management device 15 is incapable of obtaining monitoring information, as a divided-transfer time. The monitoring unit 301 in the management device 15, which has calculated the divided-transfer time, transmits a monitoring-information setting request by using the satellite channel (Step S74). The satellite communication terminals 31a, 31b, and 31c update the monitoring-information processing policy information in the storage device 207 on the basis of the monitoring-information setting request (Step S75). For example, it is assumed that this monitoring-information setting request is intended to instruct the settings for obtaining only the monitoring information including fault information from the mobile base stations 10a and 10b in the event of a disaster, that is, the settings for transferring only the monitoring information including fault information. Therefore, upon receiving monitoring information, other than the monitoring information including fault information, the satellite communication terminals 31a, 31b, and 31c perform a monitoring-information processing policy determination, and discard this received monitoring information (Step S76). The monitoring information including fault information for example, an SNMP packet with a specific value stored in “Specific Trap Type”, as illustrated in the processing number 6 in
The mobile base station 10c that continuously communicates with the core network device 13 performs a monitoring-information processing policy determination on the periodically-received monitoring information, and continuously discards this monitoring information on the basis of the processing details (Step S76). The periodically-received monitoring information is supposed to be monitoring information corresponding to the processing number 4 in
As described above, according to the present embodiment, a monitoring-information processing unit that determines the monitoring information processing is provided in the satellite communication terminal 31, so as to limit the monitoring information to be transferred through the satellite channel by using the monitoring-information processing policy information. Therefore, even at the time of a major disaster, the communication system can efficiently collect the device state of the communication infrastructure devices in the ground radio communication system. Also, the communication system can monitor the ground radio communication system by using satellite communication with high reliability, while minimizing heavy communication traffic and congestion of the satellite channel.
The configurations described in the above embodiment are only examples of the content of the present invention. The configurations can be combined with other well-known techniques, and a part of each configuration can be omitted or modified without departing from the scope of the present invention.
10, 10a, 10b, 10c mobile base station, 11a, 11b, 11c, 21 service area, 12a, 12b, 12c mobile radio signal, core network device, 14 wired line, 15 management device, 20 satellite, 22a, 22b satellite radio signal, 23 satellite base station, 30a, 30c mobile device, 31, 31a, 31b, 31c satellite communication terminal, 100, 200, 300, 500 wired I/F unit, 101, 501 device management unit, 102, 202, 502 wireless I/F unit, 103, 203, 503 radio control unit, 104, 205, 303, 504 power unit, 105, 207, 304, 505 storage device, 106, 208, 506 antenna unit, 201 monitoring-information processing unit, 206 battery unit, 301 monitoring unit, 302 display unit, 305 input unit.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/JP2015/067347 | 6/16/2015 | WO | 00 |
