JP5550295B2 - COMMUNICATION SYSTEM, SERVER DEVICE, AND COMMUNICATION METHOD - Google Patents

Description

  The present invention relates to a communication system including a terminal device, a plurality of base station devices that perform wireless communication with the terminal device, and a server device that exchanges information with the plurality of base station devices.

  Today, in a communication system that performs mobile communication, when a mobile terminal device and a base station device A are communicating, a communication area of a base station device A where the terminal device is located is communicated with another base station device B. When a transition such as a decrease in received power is detected, a handover (or handoff) is performed, and a new base station device B is connected with the end of communication with the base station device A that has been communicating so far. There is a technology for starting communication with and maintaining the communication state.

  In order to realize such a handover, the base station apparatus B needs to be waiting in a communicable state (operating state) from when the terminal apparatus is communicating with the base station apparatus A.

  For this reason, generally, the base station apparatus is always operating regardless of whether or not communication with the terminal apparatus is being performed.

  The cited document (non-patent document) describes a handover in the WiMAX system.

  Published by The Radio Industry Association ARIB STD-T94 Version 1.3 OFDMA Broadband Mobile Wireless Access System (WiMAXTM applied in Japan)

  In the communication system as described above, in order for the base station apparatus of the wireless communication system to always be able to provide a wireless service, even if there is no terminal device that is currently using the wireless service in its own area, There is a possibility that the power supply power is wasted because it is necessary to keep the power on, for example, to be always turned on.

  In addition, small base station devices may be installed in extremely small areas where the radio waves of normal base station devices do not reach. In such cases, the number of users increases and decreases according to the time of day, and there are no users. Also become prominent.

  However, even if the number of users is small, if the power of the base station apparatus is turned off, the wireless terminal apparatus of the user who has moved from the adjacent base station apparatus cannot be detected and handover cannot be performed. Will be out of service area and will not be able to provide wireless communication services.

  The communication system according to the present invention includes a terminal device, a plurality of base station devices that perform radio communication with the terminal device, and a server device that exchanges information with the plurality of base station devices. A power detection unit that receives a radio signal from the terminal and detects received power; a position information acquisition unit that acquires position information of a terminal device based on detection of predetermined power by the power detection unit; and a server device , Selecting a base station device to be handed over based on location information, and a state instruction unit for instructing the selected base station device, and a base station device selected based on the state instruction by the selected base station device And a base station apparatus state control unit that controls the state.

  Furthermore, the status indication unit indicates that the position of the base station device or the cell area that can be provided by the base station device is closer than a predetermined distance or relatively close to another base station device with respect to the position information of the terminal device. , It may be included in the conditions for selecting as a target base station apparatus.

  Furthermore, after acquiring the location information of the terminal device, the terminal device is instructed to perform handover.

  In a communication system including a plurality of base station devices that perform wireless communication with a terminal device, the terminal device according to the present invention receives a radio signal from a base station device that is a communication partner in the terminal device and detects predetermined received power And a power detection unit that transmits the detection result to the base station apparatus by wireless communication.

  A terminal device in the present invention is a terminal device in a communication system including a plurality of base station devices that perform wireless communication with the terminal device, a position information acquisition unit that acquires position information of the terminal device in the terminal device, and a terminal device Alternatively, the base station apparatus transmits the position information to the base station apparatus based on detecting that the received power from the communication partner is lower than a predetermined power.

  The terminal device in the present invention includes a GPS (Global Positioning System) receiving unit as a position information acquisition unit in a communication system including a plurality of base station devices that perform wireless communication with the terminal device. In the terminal device or the base station device, Based on the fact that a radio signal from a base station device or terminal device that is a communication partner is received and a predetermined received power is detected, a location information acquisition unit that acquires location information from a GPS reception unit, and the acquired location information, It transmits to a base station apparatus by radio | wireless communication, It is characterized by the above-mentioned.

  A terminal device according to the present invention is a terminal device in a communication system including a terminal device, a plurality of base station devices that perform radio communication with the terminal device, and a server device that exchanges information with the plurality of base station devices. Alternatively, the base station apparatus receives a radio signal from a base station apparatus or terminal apparatus that is a communication partner, and receives a predetermined signal transmitted from a plurality of base station apparatuses and a power detection unit that detects predetermined reception power. Thus, the predetermined signal reception power information based on the reception power value for each of the plurality of base station devices is obtained, and the predetermined signal reception power information is transmitted to any of the plurality of base station devices based on the detection of the predetermined reception power. And transmitting means.

  A base station apparatus in the present invention is a base station apparatus in a communication system including a terminal apparatus, a plurality of base station apparatuses that perform radio communication with the terminal apparatus, and a server apparatus that exchanges information with the plurality of base station apparatuses. The power detection unit is provided in the base station apparatus, receives a radio signal transmitted from the terminal apparatus, and detects reception power of the received radio signal.

  A base station apparatus in the present invention is a base station apparatus in a communication system including a terminal apparatus, a plurality of base station apparatuses that perform radio communication with the terminal apparatus, and a server apparatus that exchanges information with the plurality of base station apparatuses. The terminal device receives a predetermined signal transmitted from a plurality of base station devices, obtains predetermined signal received power information based on a received power value for each of the plurality of base station devices, and selects one of the plurality of base station devices. The base station apparatus receives the predetermined signal received power information, and the base station apparatus receives the predetermined signal received power information from the relationship between the information regarding the position of the base station apparatus included in the predetermined signal received power information and the received power at the terminal apparatus. A position information acquisition unit that acquires position information of the terminal device is included.

  A base station apparatus in the present invention is a base station apparatus in a communication system including a terminal apparatus, a plurality of base station apparatuses that perform radio communication with the terminal apparatus, and a server apparatus that exchanges information with the plurality of base station apparatuses. A plurality of base station devices receive a predetermined signal from a predetermined terminal device, and information based on the received power value for each of the plurality of base station devices is transmitted to the server device.

  A base station apparatus in the present invention is a base station apparatus in a communication system including a terminal apparatus, a plurality of base station apparatuses that perform radio communication with the terminal apparatus, and a server apparatus that exchanges information with the plurality of base station apparatuses. The terminal device or the base station device receives a radio signal from a communication partner and detects a received power, and a position information acquisition that acquires the position information of the terminal device based on detecting a predetermined power And after acquiring the position information of the terminal device, the terminal device is instructed to perform handover.

  The base station apparatus according to the present invention is a base station apparatus in a communication system including a server apparatus that exchanges information with a plurality of base station apparatuses. The server apparatus instructs the selected base station apparatus to select a state. The base station apparatus includes a base station apparatus state control unit that controls the state of the base station apparatus selected based on the state instruction.

  A base station device in the present invention is a server device in a communication system including a terminal device, a plurality of base station devices that perform radio communication with the terminal device, and a server device that exchanges information with the plurality of base station devices, The terminal device or base station device receives a radio signal from the base station device or terminal device that is a communication partner, and acquires position information of the terminal device based on detection of predetermined received power. Receives predetermined signals transmitted from a plurality of base station devices, obtains predetermined signal received power information based on received power values for each of the plurality of base station devices, and transmits a predetermined signal to any of the plurality of base station devices. The received power information is transmitted, the base station apparatus receives the predetermined signal received power information, the information regarding the position of the base station apparatus included in the predetermined signal received power information and the received power in the terminal apparatus From relationship, characterized in that it comprises a position information acquisition section which acquires position information of the terminal device.

  A server device in the present invention is a server device in a communication system including a terminal device, a plurality of base station devices that perform wireless communication with the terminal device, and a server device that exchanges information with the plurality of base station devices. The base station apparatus receives a predetermined signal from a predetermined terminal apparatus, transmits information based on the received power value for each of the plurality of base station apparatuses to the server apparatus, and information on the positions of the plurality of base station apparatuses and the base station A position information acquisition unit that acquires position information of the terminal device based on the received power value for each device is provided.

  A server device according to the present invention is a server device in a communication system including a terminal device, a plurality of base station devices that perform wireless communication with the terminal device, and a server device that exchanges information with the plurality of base station devices. In the device or base station device, the radio signal from the base station device or terminal device that is the communication partner is received, the predetermined reception power is detected, and the location information of the terminal device is obtained. It includes a state instructing unit that selects a base station device to be handed over based on position information and issues a state instruction to the selected base station device.

  Furthermore, the server device according to the present invention includes a state instruction unit, is included in any of a plurality of base station devices, communicates with another base station device via a communication network, and is selected. It is good also as performing the state instruction | indication.

  A server device according to the present invention is a server device in a communication system including a terminal device, a plurality of base station devices that perform wireless communication with the terminal device, and a server device that exchanges information with the plurality of base station devices. The device or base station device receives the radio signal from the base station device or terminal device that is the communication partner, acquires the position information of the terminal device based on the detection of the predetermined power, and performs handover based on the position information A state instructing unit that instructs the selected base station device, and the state instructing unit can provide the position of the base station device or the base station device with respect to the position information of the terminal device. The cell area is included in a condition for selecting as a target base station device that the cell area is closer than a predetermined distance or relatively close to another base station device. That.

  A server device according to the present invention is a server device in a communication system including a terminal device, a plurality of base station devices that perform wireless communication with the terminal device, and a server device that exchanges information with the plurality of base station devices. The device or base station device receives a radio signal from the base station device or terminal device that is the communication partner, detects a predetermined power, acquires the position information of the terminal device based on the detection, and After the location information is acquired, the terminal device is instructed to perform a handover.

  A communication method according to the present invention is a communication method in a communication system including a terminal device, a plurality of base station devices that perform wireless communication with the terminal device, and a server device that exchanges information with the plurality of base station devices. In the device or the base station device, the step of receiving a radio signal from the communication partner and detecting the power, the step of acquiring the position information of the terminal device based on the detection of the predetermined power, and the server device, The step of selecting a base station device to be handed over based on the location information and instructing the selected base station device to perform a state instruction, and the selected base station device controlling the state of the selected base station device based on the state instruction And a step of performing.

  As described above, according to the present invention, when there is no wireless communication user in the area, the base station device can be set in the power saving mode, and the power consumption can be reduced. Particularly in a base station apparatus in which a user is not usually in the area, the power consumption can be greatly reduced.

1 is a configuration diagram of a communication system according to a first embodiment of the present invention. It is a block diagram of the configuration of a terminal device according to an embodiment of the present invention. It is a block diagram of the configuration of a base station apparatus according to an embodiment of the present invention. It is a block diagram of a server device according to an embodiment of the present invention. FIG. 2 is a sequence diagram showing a flow of the present invention in the system configuration shown in FIG. 1 according to the first embodiment of the present invention. It is a block diagram of the communication system which concerns on the 2nd Embodiment of this invention. FIG. 7 is a sequence diagram showing a flow of the present invention in the system configuration shown in FIG. 6 according to a second embodiment of the present invention.

(Configuration according to the first embodiment of the present invention)
Hereinafter, the configuration and procedure of the present invention will be described with reference to the drawings.

  FIG. 1 is a configuration diagram of a communication system 10-1 according to an embodiment of the present invention.

  The terminal device 100 is communicating with the base station device 200-1. At this time, the range (cell area) in which the base station apparatus 200-1 can provide the communication service is the range indicated by the circle of the cell area 201.

  Base station apparatus 200-1 is connected to server apparatus 300 through a communication network or the like, and exchange of control information and other information is performed through this communication network. The communication network may be the Internet network or ISDN network.

  In addition to the base station device 200-1, the server device 300 is connected to a plurality of base station devices such as the base station device 200-2, the base station device 200-3, and the base station device 200-4 through a communication network. Yes.

  The plurality of base station apparatuses in the communication system 10-1 each have a cell area, and often overlap with the cell areas of other base station apparatuses.

  When the terminal apparatus 100 moves in an overlapping part of this cell area, communication can be continued by performing a handover.

  An example of the handover operation will be described with reference to FIG.

  When the terminal device 100 moves in the movement direction indicated by the arrow in the figure during communication with the base station device 200-1, the distance from the base station device 200-1 increases as the end of the cell area 201 is approached. The average received power decreases in each of the base station device 200-1 and the terminal device 100 in communication.

  If the power decreases as it is, any of the devices that perform communication becomes a reception power that cannot be communicated, and communication is interrupted.

  In many communication systems that can be handed over, the handover process is started when either the base station apparatus 200-1 or the terminal apparatus 100 detects a received power that is lower than a predetermined received power.

  When the handover process is started, the terminal apparatus 100 searches for a base station apparatus that can be received at that position.

  This search is performed by, for example, receiving a signal (for example, a signal called a broadcast signal or a control signal) transmitted unilaterally by each base station device regardless of the presence or absence of a communication partner, and a base station included in the received signal This is performed for a list in which identification ID information and received power are stored or recorded for each device.

  The base station apparatus that has the highest received power is searched by the search, and the base station apparatus that is the handover destination is determined by the identification ID of this base station apparatus.

  In FIG. 1, if the terminal device 100 performs a handover operation on the arrow indicating the moving direction at a location where the terminal device 100 has moved to the end of the cell area 201, the terminal device 100 is in the cell area 202 of the base station device 200-2. Therefore, the base station apparatus 200-2 can be detected as the handover destination base station apparatus by the above-described search.

  The operation of the terminal device 100 after the terminal device 100 detects the base station device 200-2 starts communication with the base station device 200-2 and communicates with the base station device 200-1 that has been communicating so far. What is necessary is just to cut | disconnect communication.

  The communication performed by the terminal apparatus 100 is performed to a predetermined communication apparatus (not shown) on the communication network via the base station apparatus 200-1 before the handover is performed. After the handover, the base station apparatus The base station apparatus that mediates communication is switched on the network side so that the same predetermined communication apparatus is performed via 200-2.

  You may operate | move so that the server apparatus 300 may perform such a switching operation | work by exchanging information with each base station apparatus.

  By the way, in the above-described handover operation, there is an operation in which the terminal device 100 receives a signal transmitted from the base station device in order to detect a cell area at the destination of the terminal device 100.

  As described above, in order for the terminal device 100 to appropriately detect the base station device that is the target of the handover destination at the destination, it is generally necessary to provide some information from the base station device 200-2 side. .

  In other words, if the operation of the base station apparatus 200-2 is stopped or the transmission power is reduced, the terminal apparatus 100 has an appropriate base station apparatus 200-2 as a handover destination. It is impossible to perform handover to this base station apparatus.

  This is because, for example, a person who manages many base station devices stops the operation of a base station device that is not frequently used in order to reduce power consumption by the base station device, or a control signal transmitted by the base station device, etc. It is difficult to take measures such as lowering the transmission power of the control signal in order to reduce the interference caused by.

  Therefore, the present invention normally sets the operation state of the base station apparatus based on the detection of the terminal apparatus that requires the handover even when the base station apparatus that is not in the communication state is in the stopped state or the transmission power reduction state. We propose a method to return to the operating state.

  Further, at this time, it is proposed that the base station apparatus to be returned to the normal operation state is selected based on the position information of the terminal apparatus, thereby further suppressing unnecessary transition of the base station apparatus to the normal state.

  FIG. 2 is a configuration block diagram of a terminal device according to the embodiment of the present invention.

  The terminal device 100 includes a wireless unit 110 that performs wireless signal transmission processing and reception processing in order to perform wireless communication.

  In addition, the terminal device 100 includes a communication control unit 112 that controls the wireless unit 110 and the like in order to perform an operation in accordance with a communication protocol (protocol) such as a wireless communication procedure with the base station device 200 and a handover operation procedure. Yes.

  In addition, the terminal device 100 includes a received power measuring unit 114 for measuring the received power of the signal received by the radio unit 110. Note that a reception state detection unit (not shown) for detecting the reception state may be provided. In order to detect the reception state, power, electric field strength, SNR (Signal-to-Noise Ratio), SIR (Signal) are detected. -To-Interference Ratio), SINR (Signal-to-Interference-plus-Noise Ratio), CNR (Carrier-to-Noise Ratio), CIR (Carrier-to-Interference Ratio), CINR (to-Inter-Ratio) , EVM (Error Vector Magnitude), communication error rate, communication error count, delay profile, included in received signal The amount of correlation with the known signal, the convergence state of the adaptive signal processing, and the like may be referred to. Hereinafter, a case where received power is used will be described.

  In addition, an application processing unit 118 for performing processing according to the reception power measurement result is provided.

  The application processing unit 118 is a computer, and may include a control unit (not shown) that controls the operation unit 120 and the display unit 122 of the terminal device 100, a CPU (not shown), and a memory (not shown). Here, the control unit that controls the operation unit 120 and the display unit 122 controls information input to the device operator and information output to the device operator.

  The operation unit 120 is a conversion unit that converts a key matrix (such as a numeric keypad), a cross key, a single key, a slide switch, and other user operations into electrical signals.

  The display unit 122 may be an output device that displays characters and images, such as an LCD or an OLED, or an LED or other optical element that controls light emission, polarization, light shielding, reflection, and the like of a single unit.

  The application processing unit 118 compares the power value measured by the reception power measuring unit 114 with a predetermined value, and can estimate that the end of the cell area has approached when the power value becomes smaller.

  When it is possible to estimate that the end of the cell area has been approached, the terminal apparatus performs a handover process. The communication control unit 112 performs an operation defined by such a communication protocol.

  When the application processing unit 118 can estimate that the end of the cell area has been approached, the application processing unit 118 informs the currently communicating base station apparatus (base station apparatus 200-1 in FIG. 1) that the end of the cell area has been approached. Communicate the message shown. Note that the application processing unit 118 may act on the communication control unit 112 when performing such an operation. Specifically, information (power, location, etc.) necessary for realizing the present invention may be put on a message defined by the communication protocol and sent to the base station apparatus 200 or the like.

  Further, the terminal device 100 may include a position information acquisition unit 124. Thereby, when it is estimated that the end of the cell area has been approached, the current position information is acquired, and the position information is transmitted together with the message indicating that the end of the cell area has been approached to the base station apparatus 200-1. You may send it to.

  Note that the position information acquisition unit 124 may acquire latitude, longitude, and altitude information by a GPS receiving unit that includes a GPS (Global Positioning System) receiver, for example.

  In addition, the reception power when a plurality of base station devices 200 perform radio transmission and receive a control signal is recorded together with an identification ID for identifying the transmission source base station device 200, and the list is transmitted to the base station device 200. Thus, the base station apparatus 200 or the server apparatus 300 to which the base station apparatus 200 connects through the communication network analyzes the list, and the position of the base station apparatus 200 in the list and the received power of the terminal apparatus 100 that created the list A method may be used in which the approximate distance derived from the above relationship is compared with a plurality of different base station devices 200 to determine the approximate position of the terminal device 100.

  FIG. 3 is a configuration block diagram of the base station apparatus according to the embodiment of the present invention.

  The base station apparatus 200 includes a wireless unit 210 that performs wireless signal transmission processing and reception processing in order to perform wireless communication. The base station apparatus 200 of FIG. 3 is an example in which the radio unit 210 includes an array antenna configured with a plurality of antenna elements.

  Radio section 210 has a received power measuring section (not shown) for measuring the received power of the received signal. Note that a reception state detection unit (not shown) for detecting the reception state may be provided. In order to detect the reception state, power, electric field strength, SNR (Signal-to-Noise Ratio), SIR (Signal) are detected. -To-Interference Ratio), SINR (Signal-to-Interference-plus-Noise Ratio), CNR (Carrier-to-Noise Ratio), CIR (Carrier-to-Interference Ratio), CINR (to-Inter-Ratio) , EVM (Error Vector Magnitude), communication error rate, communication error count, delay profile, included in received signal The amount of correlation with the known signal, the convergence state of the adaptive signal processing, and the like may be referred to. Hereinafter, a case where received power is used will be described.

  The communication control unit (PHY) 212 uses the wireless unit 210 and the like in order to perform an operation in accordance with the protocol of the physical layer among the communication protocols (protocols) such as a wireless communication procedure with the terminal device 100 and a handover operation procedure. Control.

  The array antenna signal processing unit 216 uses a plurality of antenna elements provided in the above-described radio unit 210, and at the time of reception and transmission, an adaptive array antenna (AAA) and a smart antenna (SA). ), MIMO (Multiple Input Multiple Output), MISO (Multiple Input Single Output), SIMO (Single Input Multiple Output), or SISO (Single Input Single Output), or uni: Sce (Single Input Single Output). Signal processing.

  The communication control unit (MAC) 214 includes a communication control unit (PHY) 212 and an array antenna signal processing unit in order to perform an operation in accordance with a communication protocol similar to that of the communication control unit (PHY) 212, in particular, a protocol related to the MAC layer. 216 is controlled.

  The power supply unit 218 supplies power to each unit configuring the base station apparatus 200. In FIG. 3, only destinations where information such as control signals and communication signals are exchanged are described, and electric wires that supply power from the power supply unit 218 are not described, but are assumed to be supplied to each component. .

  The power supply unit 218 can selectively turn on / off the power supply destination by receiving the control signal. Alternatively, it may be possible to control the transmission power by adjusting the power supply to the radio unit.

  A network I / F unit 224 (I / F is an abbreviation for InterFace) is an interface for connecting the base station apparatus 200 to a communication network. The base station apparatus 200 can exchange information with the server apparatus 300 connected to the communication network and other base station apparatuses through the network I / F unit.

Base station apparatus state control section 220 controls the operating state of base station apparatus 200. There are several operating states of the base station apparatus 200 depending on the purpose. Examples of such operating states are as follows.
Normal operation state (active mode): Communication with the terminal device 100 can be started and communication can be continued, and the power for transmitting the control signal is transmitted with the specified value of the communication protocol, so the base station device 200 can provide Communication terminal apparatus 100 entering the cell area can detect the base station apparatus as usual.
-Power OFF: When there is no problem even if the operation of the base station device 200 is stopped, such as when communication with the terminal device 100 is not being performed, the power of unnecessary portions is turned off for the purpose of reducing power consumption as much as possible. Turn off. At this time, when a message is sent from the outside of the base station apparatus 200, for example, via the communication network to turn the power on again, the network I / O is received so that the message can be received. Turn off all power supply to other components of the base station device 200 so that power is supplied only to the components of the F unit 224 and the base station device state control unit 220 that controls the base station device state. It is also good.
・ Standby state: When the base station apparatus state control unit receives a power-on message via the communication network, it takes a long time from the start of power supply to the normal operation state so that it can return to the normal operation state as quickly as possible. For example, it may be effective to activate an amplifier for amplifying a transmission signal, a computer for operating and managing the base station apparatus 200 in advance, unlike the above-described power-off state.
・ Transmission power suppression state: In places where the number of communication users changes drastically with time, the number of base station devices may become extremely large in order to match the installation amount of base station devices to the peak number of users. is there. In such a case, even when the number of communication users is small, the base station apparatus 200 constantly transmits a control signal because the base station device 200 is in a normal operation state. Therefore, interference occurs between radio signals due to the presence of an unnecessary control signal. There is no guarantee that such harmful effects will not occur. In order to reduce the probability of occurrence of such an event, it may be effective to reduce (suppress) transmission power.

  The “normal operation state” may be referred to as “active mode”, and “power off”, “standby state”, and the like may be referred to as “power saving mode”.

  The additional function processing unit 222 is configured so that the base station apparatus 200 simply executes the wireless communication protocol and functions as a signal converter between the communication network and the wireless signal via the network I / F unit. When information is acquired, or when the base station apparatus 200 has an additional function, such as when the base station apparatus 200 having the server apparatus 300 in a different location from the base station apparatus 200 is accommodated in the description of FIG. It is the component used.

  FIG. 4 is a block diagram showing the configuration of the server device according to the embodiment of the present invention.

  The server apparatus 300 has a role of aggregating and managing a plurality of base station apparatuses 200 and performing control according to the communication protocol of the wireless communication system.

  The base station device managed by the server device 300 is determined in advance, and even a base station device existing on the same communication network may be managed by another server device. The base station apparatus managed by the server apparatus may be changed later.

  The network I / F unit 310 is an interface for connecting the server device 300 to a communication network. The server device 300 can exchange information with the base station device 200 connected to the communication network and other server devices through the network I / F unit.

  The server control unit 312 is a control device that covers the overall functions of the server device 300.

  A U / I control unit 314 (U / I is an abbreviation of User Interface) controls the operation unit 320 and the display unit 322, and controls information input from the device operator and information output to the device operator.

  The operation unit 320 is a conversion unit that converts a key matrix (such as a numeric keypad), a cross key, a single key, a slide switch, and other user operations into electrical signals.

  The display unit 322 may be an output device that displays characters and images, such as an LCD or an OLED, or an LED or other optical element that controls light emission, polarization, shading, reflection, or the like of a single unit.

  The terminal device location information acquisition unit 326 acquires location information of the terminal device 100 as location information by exchanging information with the communication terminal device 100 or the base station device 200 via a communication network, or information based on location. This is the part that is identified or estimated by information processing such as computation.

  In addition, the method for acquiring the position information of the terminal device 100 includes a method using the position information acquisition unit 124 of the terminal device 100 described above, and a method based on received power in the terminal device 100 of signals transmitted from a plurality of base station devices 200. In addition, the server apparatus 300 aggregates information on received power when signals transmitted from a predetermined terminal apparatus 100 are received by a plurality of base station apparatuses 200, and the additional function processing unit 222 The position may be estimated.

  The base station apparatus state instructing unit 328 instructs a state to be changed to the base station apparatus to be controlled by sending a message to the base station apparatus state control unit 220 of the base station apparatus 200 via the communication network.

  The base station apparatus position information storage unit 330 stores information regarding the position where the base station apparatus 200 is installed. By comparing the position information of the base station apparatus and the position information of the terminal apparatus, the base station apparatus state instruction unit 328 selects the base station apparatus whose state should be changed.

  The wireless communication system protocol control unit 332 controls the communication protocol from the server device side when the terminal device 100 and the base station device 200 configure the wireless communication system 10-1. Specifically, at the time of handover, he is involved in delivery of communication between base station apparatuses.

  FIG. 5 is a sequence diagram showing the flow of the present invention in the system configuration shown in FIG. 1 according to the first embodiment of the present invention.

  First, when the terminal device 100 and the base station device 200-1 are talking (step 502) and the base station device 200-2 is in a standby state (step 504), the terminal device 100 gradually increases. Operation is shown for a case where the base station apparatus 200-2 is approached away from -1.

  At a certain point in time, the terminal device 100 detects that the power for receiving the radio signal from the base station device 200-1 is below a predetermined value X (step 506). The predetermined value is preferably larger than the power value for starting handover so that detection can be performed at an earlier stage than for starting normal handover.

  The terminal device 100 notifies the base station device 200 in communication that the received power has fallen below the predetermined value X using information transmission means (such as a control message) in accordance with the communication protocol (step 508).

  5 illustrates the operation when the application processing unit 118 detects a predetermined X or less from the measurement result of the reception power measurement unit 114 of the terminal device 100. However, the base station device 200- On the one side, it may be detected based on the received power of the radio signal from the terminal device 100 that it is in a predetermined position.

  In response to the notification from the terminal device 100, the base station device 200-1 also detects that the received power has fallen below the predetermined value X (step 510).

  This detection may be performed in a new processing unit that understands the transmitted information using a message on a communication protocol of a conventional wireless communication system. In this embodiment, it is assumed that this processing is performed by the additional function processing unit 222 in the base station apparatus 200-1.

  Upon detecting that the received power has fallen below the predetermined value X, the additional function processing unit 222 operates to acquire the position information of the terminal device 100.

  In the present embodiment, a case where the terminal device has position information acquisition means and the terminal device acquires the position information will be described.

  Specifically, the additional function processing unit 222 instructs the terminal device 100 using a message on the communication protocol to notify the location information (step 512).

  In response to the instruction to notify the location information, the terminal device 100 acquires the location information of the terminal device 100 using the location information acquisition unit 124 (step 514).

  The application processing unit 118 of the terminal device 100 controls the communication control unit 112 to notify the acquired position information to the base station device 200-1 using a message (step 516).

  The additional function processing unit 222 of the base station device 200-1 receives the location information from the terminal device 100 and notifies the server device 300 of the location information (step 518).

  The terminal device location information acquisition unit 325 of the server device 300 acquires the location information of the terminal device 100 when notified from the base station device 200-1 (step 520).

  The server control unit 312 of the server device 300 acquires the acquired location information of the terminal device, the location information of the base station device stored in the base station device location information storage unit 330 in advance, or information on the cell area of the base station device Using any one or more of judgments such as proximity to the location of the terminal device 100, whether or not the location of the cell area terminal device is included, and the success rate of the handover performed in the past, as judgment criteria, The terminal device 100 selects a base station device that is more advantageous for the handover destination (step 522).

  The base station apparatus state instructing unit 328 of the server apparatus 300 instructs the base station apparatus 200-2 that is the selected base station apparatus to set the state of the base station apparatus to the normal operation state (step 524).

  The base station apparatus state control unit 220 of the base station apparatus 200-2 sets the base station apparatus 200-2 in a normal operation state based on an instruction from the server apparatus (step 526).

  At this time, as in the example of FIG. 5, the state transition to the normal state is performed in the standby state, but the operation for the state transition does not have to be performed in the normal operation state.

  Thereafter, the terminal apparatus 100 further moves, and starts a handover operation when the power of the received signal falls below a threshold value for determining handover activation. At this time, since the base station apparatus 200-2 is already in the normal operation state and transmits the control signal, the terminal apparatus 100 can perform the handover as usual (step 528).

  In the above description, the case where the server apparatus 300 exists independently on the communication network has been described. However, the function of the server apparatus 300 may be included in a selected base station apparatus. In this case, the base station device including the function of the server device is connected to the communication network, whereby other base station devices are aggregated and managed.

  In the above description, an example in which the terminal apparatus voluntarily initiates the handover has been described. However, if the communication system can start the handover operation on the base station apparatus side, the base station apparatus 200-2 that is a candidate for the handover destination When the operation state becomes normal operation, the terminal device 100 may be caused to execute handover.

  For this reason, the base station apparatus state control unit 220 of the base station apparatus 200-2 sends the state instruction to the server apparatus 300 that has instructed the state transition, for example, when the state transition has been completed or has already been instructed. You may have the function to notify.

  In addition, when the server apparatus 300 receives a notification of the end of the state transition from the base station apparatus 200-2, the server control unit 312 may control the wireless communication system protocol control unit 332 so that the handover is executed. .

  The base station apparatus state instructing unit 328 of the server apparatus 300 detects the predetermined condition based on the detection of a predetermined condition such as a base station apparatus that has not performed wireless communication for a predetermined time in a place where the traffic difference due to time is significant. The state may be instructed to change to a power-off, standby state, transmission power suppression state, or the like.

  Further, the base station apparatus state control unit 220 of the base station apparatus 200 may operate so as to transition to a power OFF state, a standby state, a transmission power suppression state, or the like based on the absence of wireless communication for a predetermined time.

  Note that a base station apparatus that transitions to a power-off, standby state, transmission power suppression state, or the like and a base station apparatus that is always in a normal operation state may be determined in advance.

For example, in a place where there is not much movement of the terminal device 100 such as a residential area, it may be possible to increase the presence rate of the base station device that maintains the normal state, while the base station beside the highway passing through the mountains In an area such as a device where it is considered that there are many connections by handover, it may be positively shifted to the power saving mode.
(Configuration according to the second embodiment of the present invention)
A description will now be given of the configuration according to the second embodiment.

  In addition, the difference with 1st Embodiment is shown and the overlapping part is not described.

  FIG. 6 is a configuration diagram of a communication system 10-2 according to the second embodiment of the present invention.

  The difference from the first embodiment is that there are a plurality of server devices that aggregate a plurality of base station devices 200.

  Each server device 300-21 and server device 300-22 are connected via a communication network, and can exchange information. In addition, each server device 300 aggregates different base station devices 200, and some of the base station devices 200 include those in which cell areas overlap or are in the vicinity.

  In FIG. 6, the cell area 205 of the base station device 200-21 aggregated in the server device 300-21 and the cell area 206 of the base station device 200-22 aggregated in the server device 300-22 partially overlap. ing.

  In such a communication system, the operation of each device when the terminal device 100-20 moves in the moving direction indicated by the arrow in FIG. 6 will be described below.

  FIG. 7 is a sequence diagram showing the flow of the present invention in the system configuration shown in FIG. 6 according to the second embodiment of the present invention.

  In FIG. 7, from step 702 to step 720, the terminal apparatus 100 is changed to the terminal apparatus 100-20, the base station apparatus 200-1 is changed to the base station apparatus 200-21, and the base station apparatus is changed from step 502 to step 520 in FIG. Since the operation is the same as when 200-2 is replaced with the base station device 200-22 and the server device 300 is replaced with the server device 300-21, the description is omitted.

  The difference from the first embodiment is after the acquisition of the terminal device position information (step 720).

  When the server apparatus 300-21 determines that there is no appropriate handover destination for the position information of the terminal apparatus 100-20, the server apparatus 300-21 operates to entrust the search for a base station apparatus serving as a handover destination to another server apparatus. At this time, the location information of the terminal device 100-20 is sent to the server device 300-22 (step 722).

  The server control unit 312 of the server device 300-22 includes the acquired location information of the terminal device, the location information of the base station device stored in the base station device location information storage unit 330 in advance, or the cell area of the base station device. Using information related to the above, it is determined whether or not the proximity to the location of the terminal device 100-20, the location of the cell area terminal device is included, the success rate of the handover performed in the past, or the like. The base station apparatus is used as a reference, and the terminal apparatus 100-20 selects or selects a base station apparatus that is more advantageous for the handover destination (step 723).

  The base station apparatus state instructing unit 328 of the server apparatus 300-22 instructs the base station apparatus 200-22 that is the selected base station apparatus to set the state of the base station apparatus to the normal operation state (step 724).

  The base station apparatus state control unit 220 of the base station apparatus 200-2 "2 sets the base station apparatus 200-22 in a normal operation state based on an instruction from the server apparatus (step 726).

  At this time, as in the example of FIG. 5, the state transition to the normal state is performed in the standby state, but the operation for the state transition does not have to be performed in the normal operation state.

  Thereafter, the terminal device 100-20 further moves, and starts a handover operation when the power of the received signal falls below a threshold value for determining handover activation. At this time, since the base station apparatus 200-22 is already in the normal operation state and transmits the control signal, the terminal apparatus 100-20 can perform the handover as usual (step 728).

  In the above description, the server apparatus 300-21 and the server apparatus 300-22 are described as being independently present on the communication network. However, the server apparatus 300-21 or the server apparatus 300- 22 functions may be included. In this case, the base station device including the function of the server device is connected to the communication network, whereby other base station devices are aggregated and managed.

10-1, 10-2 ... communication system,
100, 100-2 ... terminal device,
110: Radio section,
112 ... communication control unit,
114... Received power measuring unit,
118 ... Application processing unit,
120 ... operation unit,
122 ... display section,
124: position information acquisition means,
200, 200-1, 200-2, 200-3, 200-4, 200-21, 200-22, 200-23, 200-24 ... base station apparatus,
201, 202, 205, 206 ... cell area,
210 ... radio section,
212 ... Communication control unit (PHY),
214 ... Communication control unit (MAC),
216 ... Array antenna signal processing section,
218 ... power supply,
220 ... Base station apparatus state control unit,
222 ... Additional function processing unit,
224 ... Network I / F unit 300, 300-21, 300-22 ... Server device,
310 ... Network I / F unit 312 ... Server control unit,
314 ... U / I control unit,
320 ... operation unit,
322... Display section,
326... Terminal device position information acquisition unit,
328 ... Base station apparatus state instruction unit 330 ... Base station apparatus position information storage unit,
332: Wireless communication system protocol control unit

Claims (6)

In a communication system including a terminal device, a base station device that performs wireless communication with the terminal device, and a server device that exchanges information with the base station device,
The server device
Means for acquiring location information of the terminal device and selecting a base station device to be a handover destination of the terminal device based on the acquired location information;
When the selected base station apparatus is in an operation state in which wireless communication is stopped or suppressed, means for instructing the base station apparatus from the operation state to the normal operation state;
Means for causing the other apparatus in the same communication system to select the base station apparatus that is the handover destination of the terminal apparatus when the own apparatus cannot select the base station apparatus that is the handover destination of the terminal apparatus. ,
The selected base station apparatus is
Means for controlling the state of the device to the normal operation state based on the state instruction;
A communication system characterized by the above. The server device, based on the location information of the terminal device and the location information of a plurality of base station devices, or information on a cell area for each base station device that can be provided by a plurality of base station devices, Select the base station device to be handed over,
The system according to claim 1.   The communication system according to claim 1, wherein the server device performs control so that handover of the terminal device is performed after the state instruction is given. A server device in a communication system including a terminal device, a base station device that performs wireless communication with the terminal device, and a server device that exchanges information with the base station device,
Means for acquiring location information of the terminal device and selecting a base station device to be a handover destination of the terminal device based on the acquired location information;
When the selected base station apparatus is in an operation state in which wireless communication is stopped or suppressed, means for instructing the base station apparatus from the operation state to the normal operation state;
Means for causing the other apparatus in the same communication system to select the base station apparatus that is the handover destination of the terminal apparatus when the own apparatus cannot select the base station apparatus that is the handover destination of the terminal apparatus;
A server device comprising: The server device is included in any of a plurality of base station devices, communicates with another base station device via a communication network, and issues a status instruction to the selected other base station device. The server device according to claim 4 . A communication method in a communication system including a terminal device, a base station device that performs wireless communication with the terminal device, and a server device that exchanges information with the base station device,
The server device is
Acquiring location information of the terminal device, and selecting a base station device to be a handover destination of the terminal device based on the acquired location information;
When the selected base station device is in an operation state in which wireless communication is stopped or suppressed, the base station device performs a state instruction from the operation state to the normal operation state;
When the own device cannot select a base station device that is a handover destination of the terminal device, the other server device of the same communication system selects a base station device that is a handover destination of the terminal device;
The selected base station apparatus is
Controlling the state of the device to the normal operation state based on the state instruction;
Including a communication method.

Images