JP5806509B2 - Wireless communication system, relay device, and communication control method - Google Patents

Description

  The present invention relates to a radio communication system having a radio base station, a terminal device, and a plurality of relay devices that relay radio communication between the radio base station and the preceding terminal device, and communication in the radio communication system It relates to a control method.

  A mobile router (MR) (see, for example, Patent Document 1) relays wireless communication between a wireless base station and a terminal device. Specifically, the mobile router functions as a wireless LAN access point for terminal devices and functions as a wireless terminal for wireless base stations.

JP 2004-153802 A

  The terminal device can alternatively be connected to both the MR and the radio base station. However, the terminal device cannot determine whether wireless communication is possible with better communication quality when connected to either the MR or the wireless base station.

  Accordingly, an object of the present invention is to provide a wireless communication system and a communication control method that enable a terminal device to perform wireless communication with good communication quality.

In order to solve the above-described problems, the present invention has the following features. A feature of the present invention is that a radio base station (radio base station 300-1), a terminal device (terminal device 100), an adjacent base station (radio base station 300-2) existing around the radio base station, A wireless communication system having a plurality of relay devices (mobile routers 200) that relay wireless communication between the wireless base station and the terminal device, wherein the terminal device has a first communication quality of a second communication If better than quality, connect to the relay device, if the second communication quality is better than the first communication quality, connect to the adjacent base station, the first communication quality, The communication quality of the wireless communication between the relay device and the radio base station notified from the relay device, and the second communication quality is the connection destination of the terminal device notified from the relay device Based on neighboring base station information gained Serial terminal device is measured, and summarized in that a communication quality of wireless communication between the terminal device and the adjacent base station.

  In such a radio communication system, the terminal device is based on communication quality in radio communication between the relay device and the radio base station and communication quality in radio communication between the terminal device and the radio base station. Any one of the relay device and the wireless base station is set as a connection destination. Therefore, the terminal device can be connected to either the relay device or the radio base station having a good communication state in consideration of the communication quality in the radio communication between the relay device and the radio base station.

A feature of the present invention is a relay device that relays wireless communication between a wireless base station and a terminal device, the communication quality in wireless communication between the relay device and the wireless base station, and the wireless base and a neighbor base station information used for the communication quality is the terminal device measures between present around the station can be a destination of the terminal device and the adjacent base station and the terminal device to the terminal device The gist is to notify.

A feature of the present invention is that a radio base station, a terminal device, a relay device that relays radio communication between the radio base station and the terminal device, an adjacent base station that exists around the radio base station, A communication control method in a wireless communication system, wherein the terminal device connects to the relay device when the first communication quality is better than the second communication quality; when the second communication quality is better than the first communication quality is seen including the step of connecting to the neighboring base station, the first communication quality, the notified from the relay device, said relay device The terminal device is communication quality in wireless communication with the wireless base station, and the second communication quality is based on information of an adjacent base station that can be a connection destination of the terminal device notified from the relay device. Measured, the end And summarized in that apparatus as a communication quality of wireless communication between the adjacent base stations.

  According to the characteristics of the present invention, the terminal device can perform wireless communication with good communication quality.

1 is an overall schematic configuration diagram of a wireless communication system according to an embodiment of the present invention. It is a figure which shows the structure of the terminal device which concerns on embodiment of this invention. It is a figure which shows the structure of the mobile router which concerns on embodiment of this invention. It is a figure which shows the structure of the wireless base station which concerns on embodiment of this invention. It is a figure which shows the structure of the high-order node which concerns on embodiment of this invention. It is a sequence diagram which shows operation | movement of the radio | wireless communications system which concerns on embodiment of this invention.

  Next, an embodiment of the present invention will be described with reference to the drawings. Specifically, (1) the configuration of the wireless communication system, (2) the operation of the wireless communication system, (3) the operation and effect, and (4) other embodiments will be described. In the description of the drawings in the following embodiments, the same or similar parts are denoted by the same or similar reference numerals.

(1) Configuration of Radio Communication System FIG. 1 is an overall schematic configuration diagram of a radio communication system 1 according to an embodiment of the present invention. The radio communication system 1 includes a terminal device (UE) 100 and a mobile router (MR) 200 possessed by a user 600 who is a passenger on a bus 700, a radio base station 300-1, a radio base station 300-2, and a core network 500. Including.

  Wireless communication between the UE 100 and the MR 200 is performed by a wireless LAN method. Wireless communication between the MR 200 and the UE 100 and the wireless base station 300-1 and the wireless base station 300-2 is a public wireless communication system such as LTE (Long Term Evolution), EV-DO, HSPA (High Speed Packet Access), It is performed by WiMAX (Worldwide Interoperability for Microwave Access) or the like.

  FIG. 2 is a diagram illustrating a configuration of the UE 100. As illustrated in FIG. As illustrated in FIG. 2, the UE 100 includes a radio communication unit 110, an antenna 112, a radio communication unit 114, an antenna 116, a control unit 120, and a storage unit 130.

  The wireless communication unit 110 is configured using, for example, a radio frequency (RF) circuit, a baseband (BB) circuit, or the like. The wireless communication unit 110 can perform wireless communication with the MR 200 via the antenna 112 by the wireless LAN method.

  The wireless communication unit 114 is configured using, for example, an RF circuit or a BB circuit. The wireless communication unit 114 collects the wireless base station 300-1 and the wireless base station 300-2 (hereinafter referred to as the wireless base station 300-1 and the wireless base station 300-2) through the antenna 116 by public wireless communication. Wireless communication can be performed with the wireless base station 300 as appropriate.

  The control unit 120 is configured using, for example, a CPU (Central Processing Unit), a DSP (Digital Signal Processor), and the like. The control unit 120 controls various functions that the UE 100 has. The storage unit 130 is configured using, for example, a memory, and stores various types of information used for controlling the UE 100 and the like.

  FIG. 3 is a diagram showing the configuration of the MR 200. As shown in FIG. As illustrated in FIG. 3, the MR 200 includes a wireless communication unit 210, an antenna 212, a wireless communication unit 214, an antenna 216, a control unit 220, and a storage unit 230.

  The wireless communication unit 210 is configured using, for example, an RF circuit or a BB circuit. The wireless communication unit 210 can perform wireless communication with the UE 100 via the antenna 212 by the wireless LAN method.

  The wireless communication unit 214 is configured using, for example, an RF circuit or a BB circuit. The wireless communication unit 214 can perform wireless communication with the wireless base station 300 through the antenna 216 by a public wireless communication method.

  The control unit 220 is configured using, for example, a CPU, a DSP, or the like. The controller 220 controls various functions that the MR 200 has. The storage unit 230 is configured using, for example, a memory, and stores various types of information used for controlling the MR 200 and the like.

  FIG. 4 is a diagram showing a configuration of the radio base station 300. As shown in FIG. As illustrated in FIG. 4, the radio base station 300 includes a radio communication unit 310, an antenna 312, a wired communication unit 314, a control unit 320, and a storage unit 330.

  The wireless communication unit 310 is configured using, for example, an RF circuit or a BB circuit. The wireless communication unit 310 can perform wireless communication with the MR 200 and the UE 100 via the antenna 312 by a public wireless communication method.

  The wired communication unit 314 communicates with other radio base stations 300 via the core network 500. When LTE is adopted as the public wireless communication system, an X2 interface that is a logical communication path is established between the wireless base station 300 and another wireless base station 300.

  The control unit 320 is configured using, for example, a CPU, a DSP, or the like. The controller 320 controls various functions that the radio base station 300 has. The storage unit 330 is configured using a memory, for example, and stores various types of information used for controlling the radio base station 300 and the like.

  Next, detailed processing of the wireless communication system 1 will be described.

  The control unit 120 in the UE 100 possessed by the user 600 performs call connection processing with the control unit 220 in the MR 200 possessed by the user 600 in accordance with an operation of an operation unit (not shown) by the user 600. In the call connection process, the control unit 120 in the UE 100 recognizes an ESSID (Extended Service Set Identifier) corresponding to the MR 200. Furthermore, the control unit 120 in the UE 100 reads an authentication key for connecting to the MR 200 from the storage unit 130, and transmits the authentication key to the MR 200. When receiving the authentication key, the control unit 220 in the MR 200 performs authentication based on the authentication key and permits the UE 100 to connect. Thereby, wireless communication by the wireless LAN method is enabled between the UE 100 and the MR 200.

  Radio base stations around the MR 200 (here, the radio base station 300-1 and the radio base station 300-2) transmit notification signals and the like. The control unit 220 in the MR 200 receives notification signals and the like from the radio base station 300-1 and the radio base station 300-2. The control unit 220 in the MR 200 measures communication quality such as received signal strength indication (RSSI) and reception quality (SINR: Signal to Noise Interference Ratio) of each broadcast signal. The control unit 220 in the MR 200 performs call connection processing with a radio base station (here, the radio base station 300-1) with good communication quality. Thereby, wireless communication by the public wireless communication system is enabled between the MR 200 and the wireless base station 300-1.

  The MR 200 relays the radio communication between the UE 100 and the radio base station 300-1 by the call connection process between the UE 100 and the MR 200 and the call connection process between the MR 200 and the radio base station 300-1. It can be carried out.

  The control unit 320 in the radio base station 300-1 transmits neighbor list information to the MR 200. The neighbor list information is information of other radio base stations existing around the radio base station 300-1. The neighbor list information includes identification information of other radio base stations.

  The control unit 220 in the MR 200 receives neighbor list information. The control unit 220 in the MR 200 measures the received electric field strength (RSSI) of the signal from the radio base station 300-1. Further, the control unit 220 in the MR 200 transmits neighbor list information and information on the received electric field strength of the signal from the radio base station 300-1 (signal strength information) to the UE 100.

  The control unit 120 in the UE 100 receives neighbor list information and signal strength information. Based on the neighbor list information, the control unit 120 in the UE 100 recognizes another radio base station (neighboring base station, here, the radio base station 300-2) existing around the radio base station 300-1. The control unit 120 in the UE 100 measures the received electric field strength (RSSI) of the signal from the adjacent base station.

  Next, the control unit 120 in the UE 100 determines to switch the connection destination of the UE 100. Specifically, the control unit 120 in the UE 100 compares the value of the received electric field strength of the signal indicated by the signal strength information from the MR 200 with the value of the received electric field strength of the signal from the radio base station 300-2. .

  Furthermore, when the value of the received electric field strength of the signal indicated by the signal strength information from MR 200 is higher than the value of the received electric field strength of the signal from radio base station 300-2, control unit 120 in UE 100 proceeds to MR 200. Stay connected. On the other hand, if the value of the received electric field strength of the signal indicated by the signal strength information from the MR 200 is lower than the value of the received electric field strength of the signal from the radio base station 300-2, the control unit 120 in the UE 100 Is switched from the MR 200 to the radio base station 300-2.

  Note that when the connection destination of the UE 100 is the MR 200, not only the communication quality in the radio communication between the MR 200 and the radio base station 300-1, but also the communication quality in the radio communication between the UE 100 and the MR 200 is considered. More desirably. Therefore, the control unit 120 in the UE 100 calculates a value obtained by subtracting a predetermined value from the received electric field strength of the signal indicated by the signal strength information from the MR 200, and the calculated value and the signal from the radio base station 300-2. The received electric field strength value may be compared. In this case, the control unit 120 in the UE 100 maintains the connection to the MR 200 when the calculated value is higher than the value of the received electric field strength of the signal from the radio base station 300-2. On the other hand, the control unit 120 in the UE 100 decides to switch the connection destination from the MR 200 to the radio base station 300-2 when the calculated value is lower than the value of the received electric field strength of the signal from the radio base station 300-2. To do.

  When switching the connection destination from the MR 200 to the radio base station 300-2, the control unit 120 in the UE 100 performs call connection processing with the control unit 320 in the radio base station 300-2. Thereby, the radio | wireless communication by a public radio | wireless communication system is attained between UE100 and the radio base station 300-2.

  Thereafter, the control unit 120 in the UE 100 transmits disconnection request information to the MR 200. The disconnection request information is information for the UE 100 to request the MR 200 to end wireless communication. The control unit 220 in the MR 200 receives the disconnection request information. The control unit 220 in the MR 200 performs processing (disconnection processing) for ending wireless communication with the UE 100 according to the disconnection request information.

  Thereafter, the control unit 120 in the MR 200 measures the received electric field strength (RSSI) of the signal from the radio base station 300-1 at a predetermined cycle. Furthermore, the control unit 220 in the MR 200 transmits information on the received electric field strength (signal strength information) of the signal from the radio base station 300-1 by broadcast communication every time measurement is performed.

  The control unit 120 in the UE 100 receives the signal strength information. The control unit 120 in the UE 100 measures the received electric field strength (RSSI) of the signal from the radio base station 300-2 that is the connection destination of the UE 100 at the current time.

  Next, the control unit 120 in the UE 100 determines to switch the connection destination of the UE 100. Specifically, as described above, the control unit 120 in the UE 100 performs the reception field strength value of the signal indicated by the signal strength information from the MR 200 and the reception field strength value of the signal from the radio base station 300-2. And compare.

  Further, the control unit 120 in the UE 100 determines that the radio base station receives the signal reception field strength value of the signal indicated by the signal strength information from the MR 200 lower than the signal reception field strength value of the signal from the radio base station 300-2. Maintain connection to station 300-2. On the other hand, when the value of the received electric field strength of the signal indicated by the signal strength information from the MR 200 is higher than the value of the received electric field strength of the signal from the radio base station 300-2, the control unit 120 in the UE 100 Is switched from the radio base station 300-2 to the MR 200.

  As described above, the control unit 120 in the UE 100 calculates a value obtained by subtracting a predetermined value from the received electric field strength of the signal indicated by the signal strength information from the MR 200, and the calculated value and the radio base station 300-2 You may compare with the value of the received electric field strength of the signal from. In this case, the control unit 120 in the UE 100 maintains the connection to the radio base station 300-2 when the calculated value is lower than the value of the received electric field strength of the signal from the radio base station 300-2. On the other hand, the control unit 120 in the UE 100 determines to switch the connection destination from the radio base station 300-2 to the MR 200 when the calculated value is higher than the value of the received electric field strength of the signal from the radio base station 300-2. To do.

  When switching the connection destination from the radio base station 300-2 to the MR 200, the control unit 120 in the UE 100 performs call connection processing with the control unit 320 in the radio base station 300-2. As a result, wireless communication by the wireless LAN communication method can be performed between the UE 100 and the MR 200.

  Thereafter, the control unit 120 in the UE 100 transmits disconnection request information to the radio base station 300-2. The disconnection request information is information for the UE 100 to request the radio base station 300-2 to end radio communication. The control unit 320 in the radio base station 300-2 receives the disconnection request information. The control unit 320 in the radio base station 300-2 performs processing (disconnection processing) for ending radio communication with the UE 100 according to the disconnection request information.

(2) Operation of Radio Communication System FIG. 6 is a sequence diagram showing the operation of the radio communication system.

  In step S200, the UE 100 possessed by the user 600 performs wireless communication by the wireless LAN method with the MR 200 possessed by the user 600. In step S201, the MR 200 performs wireless communication with the wireless base station 300-1 using a public wireless communication method.

  In step S202, the radio base station 300-1 transmits neighbor list information. MR 200 receives neighbor list information. In step S203, the MR 200 transmits neighbor list information and information on the received electric field strength of the signal from the radio base station 300-1 (signal strength information). The UE 100 receives neighbor list information and signal strength information.

  In step S204, UE100 measures the received electric field strength of the signal from radio base station 300-2 which is an adjacent base station.

  In step S205, the UE 100 determines the connection destination of the UE 100 based on the received field strength value of the signal indicated by the signal strength information from the MR 200 and the received field strength value of the signal from the radio base station 300-2. decide.

  When the connection destination is determined to be the radio base station 300-2, in step S206, the UE 100 performs call connection processing with the radio base station 300-2. Thereafter, in step S207, wireless communication is performed between the UE 100 and the wireless base station 300-2 by the public wireless communication method.

  In step S208, the UE 100 transmits disconnection request information. The MR 200 receives the disconnection request information. In step S209, the MR 200 performs processing (disconnection processing) for ending wireless communication with the UE 100 according to the disconnection request information.

  Thereafter, in step S210, the MR 200 transmits information on the received electric field strength (signal strength information) of the signal from the radio base station 300-1 by broadcast communication. The UE 100 receives signal strength information. The signal strength information here may be information on the signal strength of the MR 200 signal measured by the radio base station 300-1.

  In step S211, UE100 measures the received electric field strength (RSSI) of the signal from radio base station 300-2.

  In step S212, the UE 100 determines the connection destination of the UE 100 based on the value of the received electric field strength of the signal indicated by the signal strength information from the MR 200 and the value of the received electric field strength of the signal from the radio base station 300-2. decide.

  When it is determined that the connection destination is the MR 200, the UE 100 performs a call connection process with the MR 200 in step S213. Thereafter, in step S214, wireless communication using the wireless LAN method is performed between the UE 100 and the MR 200.

  In step S215, the UE 100 transmits disconnection request information. The radio base station 300-2 receives the disconnection request information. In step S216, the radio base station 300-2 performs processing (disconnection processing) for ending radio communication with the UE 100 in accordance with the disconnection request information.

(3) Operation / Effect In the wireless communication system 1 of the present embodiment, the MR 200 that relays wireless communication between the UE 100 and the wireless base station 300-1 exists in the vicinity of the wireless base station 300-1 that is the connection destination. The neighbor list information, which is information on the radio base station 300-2 to be transmitted, and information on the received electric field strength of the signal from the radio base station 300-1 (signal strength information) are transmitted to the UE 100.

  The UE 100 receives the neighbor list information and the signal strength information from the MR 200, and measures the received electric field strength of the signal from the radio base station 300-2 recognized based on the neighbor list information. Further, the UE 100 compares the received electric field strength indicated by the signal strength information from the MR 200 with the measured received electric field strength, and sets the MR 200 or the radio base station 300-2 corresponding to the higher received electric field strength as the connection destination. To do. Specifically, when the value of the received electric field strength of the signal from the radio base station 300-2 is higher than the value of the received electric field strength indicated by the signal strength information from the MR 200, the connection destination is changed from the MR 200 to the radio base station. Switch to station 300-2.

  Therefore, if the UE 100 is connected to either the MR 200 or the radio base station 300-2, it can determine whether radio communication with good communication quality is possible, and the MR 200 and the radio base station 300 with good communication quality can be determined. -2 can perform wireless communication.

(4) Other Embodiments As described above, the present invention has been described according to the embodiment. However, it should not be understood that the description and drawings constituting a part of this disclosure limit the present invention. From this disclosure, various alternative embodiments, examples and operational techniques will be apparent to those skilled in the art.

  In the above-described embodiment, as illustrated in FIG. 1, the case where only the radio base station 300-2 exists around the radio base station 300-1 has been described. However, the present invention can be similarly applied when two or more radio base stations (adjacent base stations) exist around the radio base station 300-1.

  In this case, the UE 100 measures the received electric field strength of signals from a plurality of adjacent base stations based on the neighbor list information from the MR 200. Furthermore, UE 100 compares the received electric field strength indicated by the signal strength information from MR 200 with each measured received electric field strength, and determines MR 200 or the adjacent base station corresponding to the higher received electric field strength as the connection destination. .

  Moreover, although embodiment mentioned above demonstrated the case where a relay apparatus was a mobile router (MR), it is relay apparatuses other than a mobile router, Comprising: The function which relays the radio | wireless communication between UE100 and the radio base station 300 is demonstrated. As long as it has, the present invention can be similarly applied.

  Thus, it should be understood that the present invention includes various embodiments and the like not described herein. Therefore, the present invention is limited only by the invention specifying matters in the scope of claims reasonable from this disclosure.

  DESCRIPTION OF SYMBOLS 1 ... Wireless communication system, 100 ... UE, 110 ... Wireless communication part, 112 ... Antenna, 114 ... Wireless communication part, 116 ... Antenna, 120 ... Control part, 130 ... Memory | storage part, 200, 200-2 ... MR, 210 ... Wireless communication unit, 212 ... antenna, 214 ... radio communication unit, 216 ... antenna, 220 ... control unit, 230 ... storage unit, 300-1, 300-2 ... radio base station, 310 ... radio communication unit, 312 ... antenna, 314 ... Wired communication unit, 320 ... Control unit, 330 ... Storage unit

Claims (3)

A radio communication system comprising: a radio base station; a terminal device; a relay device that relays radio communication between the radio base station and the terminal device; and an adjacent base station existing around the radio base station Because
The terminal device
If the first communication quality is better than the second communication quality, connect to the relay device,
If the second communication quality is better than the first communication quality, connect to the adjacent base station ,
The first communication quality is a communication quality in wireless communication between the relay device and the wireless base station notified from the relay device;
The second communication quality is measured between the terminal device and the adjacent base station, measured by the terminal device based on information of an adjacent base station that can be a connection destination of the terminal device notified from the relay device. A wireless communication system which is communication quality in wireless communication. A relay device that relays wireless communication between a wireless base station and a terminal device,
Communication quality in radio communication between the relay device and the radio base station, and communication quality between an adjacent base station that exists around the radio base station and can be a connection destination of the terminal device, and the terminal device the relay apparatus to notify the, and neighbor base station information used for the terminal device measures the terminal device. A radio communication system comprising: a radio base station; a terminal device; a relay device that relays radio communication between the radio base station and the terminal device; and an adjacent base station existing around the radio base station A communication control method in
The terminal device, when the first communication quality is better than the second communication quality, connecting to the relay device;
Said terminal device, when the second communication quality is better than the first communication quality is seen including the steps of: connecting to the adjacent base station,
The first communication quality is a communication quality in wireless communication between the relay device and the wireless base station notified from the relay device;
The second communication quality is measured between the terminal device and the adjacent base station, measured by the terminal device based on information of an adjacent base station that can be a connection destination of the terminal device notified from the relay device. A communication control method that is communication quality in wireless communication .

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