JP2012100059A - Wireless communication path relay method, wireless base station device, and communication terminal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wireless communication path relay method, a wireless base station device, and a communication terminal capable of establishing a wireless communication path so that a subordinate wireless terminal of a wireless base station whose line connection with a host device is disconnected can get data communication service.SOLUTION: Notification information indicating a line disconnection state with a host device is transmitted from a wireless base station BTS1 whose line connection with the host device RNC1 is disconnected to wireless terminals MS1 and UE2 existing in a wireless area under the wireless base station BTS1. The wireless terminal UE2 existing in both wireless areas of the wireless base station BTS1 and an adjacent wireless base station BTS2 is set to be a relay terminal. Transmission and reception data to be transmitted and received between the wireless terminal MS1 and the wireless base station BTS1 is transmitted and received between the wireless base station BTS1 and the relay terminal UE2, and between the relay terminal UE2 and the wireless base station BTS2, respectively, after a relay flag is added to the data. Transmission and reception data from which the relay flag is removed is transmitted and received between the wireless base station BTS2 and a host device RNC2 of the wireless base station BTS2.

Description

  The present invention relates to a radio channel relay method, a radio base station apparatus, and a radio terminal in a mobile radio communication system. The present invention can be applied, for example, to a technique for relaying and establishing a wireless communication path of a wireless terminal located under a wireless base station that is disconnected from a host device.

  FIG. 16 shows an example of a service mode at the time of communication failure of a radio base station in a general mobile radio communication system. As shown in FIG. 16, wireless terminals (MS1, MS2) such as mobile phones located in the wireless area of the wireless base station (BTS1) are connected to the wireless base station (BTS1) through a wireless link and are higher-level devices. It is connected to the mobile communication network via the radio network controller (RNC1).

  When the line connection (for example, Iub interface) between the radio base station (BTS1) and its higher-level device (RNC1) is disconnected due to the occurrence of a disaster, etc., the radio base station (BTS1) The wireless terminal (MS2) that is also under the control of the adjacent normal wireless base station (BTS2) is replaced (handed over) to the wireless base station (BTS2). As a result, the radio terminal (MS2) is connected to the mobile communication network via the radio network controller (RNC2) at the higher level of the radio base station (BTS2).

  However, since the radio terminal (MS1) under the control of the radio base station (BTS1) is out of the service area of the other radio base station (BTS2), the accommodation change (handover) to the radio base station (BTS2) is not performed. It becomes a wireless terminal out of service area and cannot receive communication services.

  Several methods for relaying wireless communication have been proposed so that a wireless terminal can receive a communication service when a failure occurs in a wireless base station. For example, when a failure occurs in the wireless base station (BTS1), the wireless terminal (MS1) under its control establishes synchronization of communication between the other wireless terminals (MS2) and the terminals and communicates with the wireless terminal (MS2). And a method in which the wireless terminal (MS2) relays the communication data and transmits it to a mobile communication network via a normal wireless base station (BTS2) has been proposed (see, for example, Patent Document 1).

  Further, the out-of-service wireless terminal (MS1) directly transmits communication data such as an emergency call to other peripheral wireless terminals (MS2) and uses the relay mode of the other wireless terminal (MS2). A method for accessing a mobile communication network has been proposed (see, for example, Patent Document 2).

International Publication No. 2008/035424 JP 2010-10875 A

  A wireless communication relay method that has been proposed in the past in the event of a communication failure of a wireless base station is that a wireless terminal under the failure of the wireless base station where the failure has occurred is another wireless device that is under the control of another normal wireless base station. Communication data is directly transmitted / received to / from a terminal, and wireless communication is relayed using a relay function of the other wireless terminal.

  Therefore, a wireless terminal using a conventional relay method has a communication function (hardware and software) for directly transmitting / receiving data to / from another wireless terminal in addition to a communication function for transmitting / receiving data to / from a wireless base station. , It was costly. The present invention provides a wireless communication path so that a wireless terminal under a wireless base station whose line connection with a host device is disconnected can receive a data communication service without providing a communication function for directly transmitting and receiving data between wireless terminals. The purpose is to establish.

  A wireless communication path relay method as one form for solving the above-described problem is a method in which a common control signal indicating a line disconnection state with a higher-level device is transmitted from a first radio base station whose line connection with a higher-level device is disconnected. Transmit to a wireless terminal located in the wireless area, and relay the wireless terminal located in the wireless area of both the first wireless base station and the second wireless base station adjacent to the first wireless base station A first step of setting as a terminal, and transmission / reception data transmitted / received between a wireless terminal located in a wireless area of the first wireless base station and the first wireless base station, A second step of transmitting and receiving a relay flag between the base station and the relay terminal and between the relay terminal and the second radio base station, and the second radio The transmission / reception data from which the relay flag has been removed is transmitted from the base station. It is intended to include, a third step of transmitting and receiving between the host device of the second radio base station.

  Further, the radio base station apparatus as another mode is transmitted from the radio terminal, a line disconnection notification means for notifying a radio terminal located in the radio area under the control of the line disconnection state with the host apparatus by a common control signal. Receiving the relay mode information indicating whether or not the wireless terminal is relayable, selecting the relay terminal from the wireless terminals that transmitted the relay mode information indicating that the wireless terminal is relayable, and the relay terminal Between the relay terminal setting means for establishing a wireless link between the relay terminal and the transmission / reception data transmitted and received between the wireless terminal located in the subordinate radio area and the relay terminal with a relay flag attached thereto. Transmission / reception data relay means for transmitting / receiving the transmission / reception data with the relay flag removed to / from the host device.

  Further, the radio terminal as another mode receives a common control signal transmitted from the first radio base station and indicating a line disconnection state with the host device, and receives a second control signal adjacent to the first radio base station. Based on a common control signal received from a radio base station, relay mode notification means for notifying the first and second radio base stations of relay mode information indicating that the radio terminal can be relayed, and the first Transmission / reception data transmitted / received by a wireless terminal located in a wireless area under one wireless base station, the data transmitted with a relay flag added from the first wireless base station, A transmission / reception data relay means for relaying data transmitted from the second radio base station to the first radio base station by relaying to the first radio base station. .

  A radio base station in which a general radio terminal located in the radio area of both the radio base station and the neighboring radio base station that has been disconnected from the host device is used as a relay terminal, and the link to the host device is disconnected A wireless base that can establish a communication path to relay data communication of subordinate wireless terminals to other wireless base stations without directly transmitting and receiving data between wireless terminals, and the line connection with the host device is disconnected A wireless terminal under the office can receive a data communication service.

It is a figure which shows one form of the radio | wireless communication path relay of an indication. It is a figure which shows the form in case there exist multiple relay terminals. It is a figure which shows the form which connected the terminal for relay, and the base station for relay in multistage. It is a figure which shows the example of the setting procedure of the terminal for relay. It is a figure which shows the example of the establishment procedure of the relay path | route of the radio | wireless terminal under the radio | wireless base station of communication disconnection with a high-order apparatus. It is a figure which shows the example of a form of an attach signal or a transmission signal, and an incoming signal. It is a figure which shows the example of the transmission procedure from the radio | wireless terminal under the radio | wireless base station of communication disconnection with a high-order apparatus. It is a figure which shows the example of the transmission operation | movement sequence of the radio | wireless terminal under the radio | wireless base station of communication disconnection with a high-order apparatus. It is a figure which shows the example of the incoming procedure to the radio | wireless terminal under the radio base station of communication disconnection with a high-order apparatus. It is a figure which shows the example of the update procedure of the setting information of the terminal for relay. It is a figure which shows the example of the operation | movement procedure at the time of the failure recovery of a wireless base station. It is a figure which shows the structural example of the functional block of the radio | wireless terminal which operate | moves as a relay terminal. It is a figure which shows the structural example of the functional block of the radio base station which operate | moves as a relay base station. It is a figure which shows the example of a procedure of establishment of the wireless link at the time of the transmission from a wireless terminal. It is a figure which shows the example of a procedure of the radio link establishment at the time of the incoming call to a radio | wireless terminal. It is a figure which shows an example of the service aspect at the time of the communication failure of the wireless base station in a general mobile radio | wireless communications system.

  The disclosed wireless channel relay method will be described with reference to FIG. When the radio base station (BTS1) is disconnected from the host device (RNC1) due to a disaster or the like, the other radio base station (BTS2) located under the radio base station (BTS1) and adjacent thereto A general wireless terminal (UE2) that can communicate with the terminal is set as a relay terminal.

  Then, transmission / reception data of the wireless terminal (MS1) under the troubled wireless base station (BTS1) is transmitted to the normal wireless base station (BTS2) via the wireless base station (BTS1) and the relay terminal (UE2). ). By doing so, the wireless terminal (MS1) under the troubled wireless base station (BTS1) can receive a communication service via the normal wireless base station (BTS2) and its host device (RNC2).

  In addition, when the radio base station (BTS2) adjacent to the radio base station (BTS1) in the fault state is similarly disconnected from the host device (RNC2), the radio base station (BTS2) Adjacent normal radio base stations and relay terminals are connected in multiple stages to secure a radio communication path.

In order to realize the above-described wireless channel relay, the wireless base station and the wireless terminal have the following functions.
(1) When the line connection (Iub interface) with the higher level apparatus (RNC1) is disconnected, the radio base station apparatus (BTS1) autonomously transmits a common control signal to the radio terminals (MS1, UE2) under its control. Has a function of notifying of a failure state. In the following description of the embodiment, information notified from the radio base station apparatus to the radio terminal by a common control signal is referred to as broadcast information.

  (2) The radio terminal (UE2) that has received the broadcast information has a function of relaying transmission / reception data of the radio terminal (MS1) under the radio base station (BTS1). Specifically, the signal transmitted from the radio terminal (MS1) is transmitted by the radio base station apparatus (BTS1) to the relay terminal (UE2) with a relay flag. The relay terminal (UE2) receives a signal from the radio terminal (MS1) via the radio base station apparatus (BTS1), adds a relay flag to the signal, and relays the radio base station (BTS2). It has a relay function to transmit to).

  In addition, the relay terminal (UE2) transmits a call signal transmitted from the relay base station (BTS2) with a relay flag to the radio terminal (MS1) under the control of the radio base station (BTS1). Receive. Then, the relay terminal (UE2) has a relay function for transmitting the call signal with a relay flag to the radio base station (BTS1).

(3) When the relay terminal (UE2) receives the failure notification notification information from the radio base station (BTS1) that is disconnected from the host device (RNC1), the relay terminal (UE2) communicates with the other radio base station (BTS2). A function of notifying the wireless base station (BTS1) of the wireless communication status is provided.
(4) The relay terminal (UE2) periodically has a function of monitoring the radio communication status with the radio base station (BTS2) and notifying the relay destination radio base station (BTS1) of whether or not relaying is possible.

(5) The radio base station apparatus (BTS1) receives a relay attach (ATTACH) signal from the relay terminal (UE2), and creates a relay terminal (UE) candidate list creation function and the relay terminal (UE) A function for determining the priority order is provided. The attach (ATTACH) signal is a signal including a location registration request transmitted from the wireless terminal to the wireless base station for use of the wireless communication service.
(6) The radio base station apparatus (BTS1, BTS2) allocates radio resources (line disconnection mode code) to the relay terminal (UE2), and the radio base station (BTS1) in which the line connection with the host apparatus (RNC1) is disconnected A function of relaying a signal of a subordinate wireless terminal (MS1) is provided.

(7) The relay terminal (UE2) has a function of monitoring failure state broadcast information transmitted from the radio base station (BTS1) and changing the relay mode according to a change in the failure state.
(8) It has a function of determining a line disconnection mode indicating a failure state of a line connection with a host device, connecting a relay radio base station and a relay terminal in multiple stages, and relaying.

Here, a list created by the radio base station such as the above-described relay terminal (UE) candidate list will be described. Table 1 shows a relay terminal (UE) candidate list.

  In the relay terminal (UE) candidate list, the radio base station (BTS1) whose line with the host apparatus (RNC1) is disconnected receives the relay attach (ATTACH) signal from the subordinate radio terminal, and the relay terminal (UE) candidate list Based on the attach (ATTACH) signal, the number (UE-ID) of a wireless terminal that can be a relay terminal is stored.

  As shown in FIG. 2, when there are a plurality of radio terminals (UE2, UE3) that can be relay terminals, the radio base station (BTS1) determines the radio terminal number (UE-ID) in the relay terminal (UE) candidate list. ), One relay terminal (UE) is selected based on the priority order by round robin or the like.

  The relay terminal (UE) candidate list stores relay mode and radio quality information for each radio terminal number (UE-ID) in addition to the radio terminal number (UE-ID) that can be a relay terminal. It can be set as the structure to do. Here, the relay mode indicates the type of relay mode depending on the failure state of the line connection between the radio base station and the host device, and is placed on the relay attach (ATTACH) signal from each relay terminal (UE) to the radio base station ( BTS1) is notified.

  As shown in FIG. 1 or FIG. 2, the relay mode 0 is located under the radio base station (BTS1) in which the line connection with the host device (RNC1) is disconnected and is adjacent to a normal radio base station (BTS2). Is notified to the wireless base station (BTS1) from the wireless terminal (MS1) that is not in the service area, indicating that relaying is not possible.

  As shown in FIG. 1 or FIG. 2, the relay mode 1 is located under the radio base station (BTS1) in which the line connection with the host device (RNC1) is disconnected, and is adjacent to other normal radio base stations ( The radio terminals (UE2, UE3) that are also under the control of BTS2) are notified to the radio base station (BTS1), and the normal radio base station (BTS2) is connected to the host device (RNC2). Indicates that relaying is possible directly via the radio base station (BTS2).

  In relay mode 2, as shown in FIG. 3, the line of the higher-level device (RNC1) of the radio base station (BTS1) is disconnected, the line of the higher-level device (RNC2) of the adjacent radio base station (BTS2) is also disconnected, When the line of the host device (RNC3) of the adjacent radio base station (BTS3) is normally connected, the relay radio terminal (UE2) notifies the radio base station (BTS1).

  The relay radio terminal (UE2) is located under the radio base station (BTS1) in which the line connection with the host apparatus (RNC1) is disconnected, and is also located under the neighboring radio base station (BTS2). is doing. However, the adjacent radio base station (BTS2) cannot be relayed via the adjacent radio base station (BTS2) because the line with the host device is disconnected.

  However, the wireless terminal (UE2) can establish a wireless communication path via the wireless base station (BTS2), the relay wireless terminal (UE4), and the wireless base station (BTS3). Therefore, the radio terminal (UE2) notifies the radio base station (BTS1) as relay mode 2 that relaying is possible by indirect connection via the radio base station (BTS2) and the radio base station (BTS3).

  The radio quality index of the relay terminal (UE) candidate list in Table 1 indicates a comparison result between the received power of the signal from the radio base station (BTS1, BTS2) and the threshold value P in each relay terminal (UE). The radio quality indicator is put on a relay attach (ATTACH) signal and notified from each relay terminal (UE) to the radio base station (BTS1).

Table 2 shows an example of the wireless quality index.

The radio quality index X indicates that the received power of the radio base station (BTS1) is greater than or equal to the threshold value P and the received power of the radio base station (BTS2) is greater than or equal to the threshold value P.
The wireless quality index Y indicates that the received power of the wireless base station (BTS1) is equal to or higher than the threshold value P and the received power of the wireless base station (BTS2) is equal to or lower than the threshold value P.
The radio quality index Z indicates that the received power of the radio base station (BTS1) is equal to or less than the threshold value P, and the received power of the radio base station (BTS2) is equal to or less than the threshold value P.
That is, the radio quality is higher in the order of X, Y, and Z, and when the relay terminal (UE) is selected, the priority order can be determined based on this radio quality index.

  On the other hand, the relay radio terminal (UE), with respect to the relay radio base station (BTS2), the identification number (BTS-ID) of the radio base station (BTS1) to be relayed and the own terminal number (UE- ID). The relay base station (BTS2) creates a relay target base station (BTS) list based on the information.

Table 3 shows an example of the relay target base station (BTS) list.

  In the relay target base station (BTS) list, a relay terminal that can be used for relaying the radio base station (BTS) corresponding to the identification number (BTS-ID) number of the radio base station (BTS) to be relayed Holds an identification number (UE-ID) of (UE). When a signal is transmitted to a radio base station (BTS) to be relayed, if there are a plurality of relay terminals (UE) that can be used for relay of the radio base station (BTS), one relay terminal is used by round robbing or the like (UE) can be selected. The identification number (UE-ID) of the relay terminal (UE) that has not been used for a certain period is discarded.

  Further, the relay radio base station (BTS2) identifies, for each identification number (BTS-ID) of the relay target radio base station (BTS), the identification number (MS-) of the relay target radio terminal (MS) under the relay radio base station (BTS2). ID) is stored, a relay target terminal (MS) list is provided. The radio terminal (MS1) under the radio base station (BTS1) to be relayed transmits an attach (ATTACH) signal transmitted from the radio terminal (MS1) via the radio base station (BTS1) and the relay terminal (UE2). Since it is received as a relay signal at the relay radio base station (BTS2), it is recognized based on the received signal. Note that the identification number (MS-ID) of the wireless terminal (MS) that has not been used for a certain period is discarded.

Table 4 shows an example of the relay target terminal (MS) list.

  Next, the setting procedure of the relay terminal (UE2) will be described with reference to FIG. The setting of the relay terminal (UE2) is performed according to the following procedure. First, the wireless base station (BTS1) detects disconnection of the line connection (Iub interface) with the host device (4-1). In the wireless base station (BTS1), information on the line disconnection mode 0 is added to the broadcast information when the line is connected, and the information is transmitted to the wireless terminal (MS) under the wireless base station (BTS1) (4-2).

  Here, the line disconnection mode 0 indicates that relaying is not possible. Line disconnection mode 1 indicates that direct relay is possible. The line disconnection mode 2 indicates that indirect relaying is possible, that is, indirect relaying is possible via another adjacent normal radio base station. The radio base station in the line disconnection mode 1 transmits / receives relay data to / from its host device, and the radio base station in the line disconnection mode 2 transmits / receives the relay data to / from other relay terminals.

  The wireless terminal (UE2) that has received the information of the line disconnection mode 0 from the wireless base station (BTS1) receives broadcast information from the wireless base station (BTS2) with high received power other than the wireless base station (BTS1) (4 -3). The wireless terminal (UE2) checks the broadcast information of the nearby wireless base station (BTS2) (4-4).

  When the broadcast information indicates that “no other wireless base station (BTS) exists in the vicinity”, the wireless terminal (UE2) transmits a relay attach (ATTACH) signal to the wireless base station (BTS1) in the relay mode. Call 0 (relay not possible) (4-5). The radio base station (BTS1) receives the relay attach (ATTACH) signal from the radio terminal (UE2), and recognizes that the radio terminal (UE2) cannot become a relay terminal (4-6).

  When the above-described broadcast information indicates that “a normal radio base station (BTS) exists in the vicinity”, the radio terminal (UE2) relays a relay attach (ATTACH) signal to the radio base station (BTS1). It transmits as mode 1 (direct relay is possible), and notifies the radio base station (BTS2) that it has become a relay terminal of the radio base station (BTS1) (4-7).

  After receiving the relay attach (ATTACH) signal from the relay terminal (UE2), the radio base station (BTS1) adds the relay terminal (UE2) as the relay mode 1 to the relay terminal (UE) list, The radio resource of the line disconnection mode code is allocated to the relay terminal (UE2).

  The relay radio base station (BTS2) creates a relay target base station (BTS) list storing the radio base stations (BTS1) to be relayed (4-8). The radio base station (BTS1) to be relayed transmits the notification information obtained by changing the line disconnection mode 0 to the line disconnection mode 1 to the radio terminal (MS) under the radio base station (BTS1) (4-9).

  When the broadcast information from the radio base station (BTS2) indicates the line disconnection mode 1 or the line disconnection mode 2, the radio terminal (UE2) relays to the relay target radio base station (BTS1). Attached (ATTACH) signal is transmitted as relay mode 2 (indirect relay is possible), and the wireless base station (BTS2) is notified that it has become a relay terminal for the wireless base station (BTS1) (4- 10).

  The radio base station (BTS1) to be relayed receives the relay attach (ATTACH) signal from the relay terminal (UE2), and then places the relay terminal (UE2) in the relay terminal (UE) list in the relay mode 2 And the radio resource of the line disconnection mode code is allocated to the relay terminal (UE2).

  The relay radio base station (BTS2) creates a relay target base station (BTS) list storing the radio base station (BTS1) to be relayed (4-11). The radio base station (BTS1) to be relayed transmits the notification information obtained by changing the line disconnection mode 0 to the line disconnection mode 2 to the radio terminal (MS) subordinate to the radio base station (BTS1) (4-12). The setting of the relay terminal is completed by the above processing procedure.

  Next, a procedure for establishing a relay path of the wireless terminal (MS1) under the control of the wireless base station whose line with the host device is disconnected will be described with reference to FIG. Establishment of the relay path of the wireless terminal (MS1) is performed by the following processing procedure. The wireless terminal (MS1) receives broadcast information of the line disconnection mode 1 or the line disconnection mode 12 from the wireless base station (BTS1) (5-1).

  The wireless terminal (MS1) transmits a normal attach (ATTACH) signal to the wireless base station (BTS1) (5-2). When the radio base station (BTS1) receives the attach (ATTACH) signal from the radio terminal (MS1), the radio base station (BTS1) ranks the relay terminals in the previously created relay terminal (UE) candidate list and serves as a relay terminal. A path is set for the determined relay terminal (UE2) (5-3).

  The radio base station (BTS1) assigns a relay flag to the attach (ATTACH) signal from the radio terminal (MS1), and then transmits the attach (ATTACH) signal to the relay terminal (UE2) using an individual channel signal. (5-4). The relay terminal (UE2) receives the individual channel signal including the attach (ATTACH) signal from the radio terminal (MS1) relayed from the radio base station (BTS1), and then checks the relay flag.

  When the relay terminal (UE2) has a relay flag added to the received dedicated channel signal, the relay terminal (UE2) relays to the dedicated channel signal including the attach (ATTACH) signal to the radio base station (BTS2). A flag for use is assigned and transmitted to the radio base station (BTS2) (5-5).

  The radio base station (BTS2) receives the relay attach (ATTACH) signal from which the relay flag is removed from the individual channel signal including the relay attach (ATTACH) signal received from the relay terminal (UE2). ) As a signal to the higher-level device (RNC2) (5-6). The host device (RNC2) recognizes the attachment of the wireless terminal (MS1) based on the attach (ATTACH) signal from the wireless base station (BTS2) (5-7). With the above processing procedure, establishment of the relay path of the wireless terminal (MS1) is completed.

  The radio terminal (MS1) under the radio base station (BTS1) disconnected from the higher level apparatus (RNC1) is: radio base station (BTS1) -relay terminal (UE2) -radio base station (BTS2) -higher level apparatus (RNC2) In this way, attachment to the host device (RNC2) is performed. Accordingly, the wireless terminal (MS1) is treated as if it is located under the wireless base station (BTS2) connected to the host device (RNC2).

FIG. 6 shows the form of the attach signal, the outgoing signal, and the incoming signal. FIG. 6A shows a form of an attach signal or a transmission signal from the wireless terminal (MS1).
(A1) shows an attach signal or a transmission signal from the wireless terminal (MS1) to the wireless base station (BTS1).
(A2) shows a relay flag and an attach signal or a transmission signal from the radio base station (BTS1) to the relay terminal (UE2). This signal is transmitted by a dedicated channel signal.

(A3) indicates a relay flag and an attach signal or a transmission signal from the relay terminal (UE2) to the radio base station (BTS2). This signal is transmitted by a dedicated channel signal.
(A4) shows an attach signal or a transmission signal from the radio base station (BTS2) to the host device (RNC2).

FIG. 6B shows a form of an incoming signal to the wireless terminal (MS1).
(B1) shows an incoming signal from the host apparatus (RNC2) to the radio base station (BTS2).
(B2) indicates a relay flag and an incoming signal from the radio base station (BTS2) to the relay terminal (UE2). This signal is transmitted by a dedicated channel signal.

(B3) shows a relay flag and an incoming signal from the relay terminal (UE2) to the radio base station (BTS1). This signal is transmitted by a dedicated channel signal.
(B4) shows an incoming signal from the radio base station (BTS1) to the radio terminal (MS1).

  A transmission operation from the wireless terminal (MS1) under the control of the wireless base station (BTS1) whose line with the host device is disconnected will be described with reference to FIG. Transmission from the wireless terminal (MS1) is processed in the following procedure. A transmission event occurs from the wireless terminal (MS1) located under the wireless base station (BTS1) (7-1), and the wireless terminal (MS1) transmits a transmission request to the wireless base station (BTS1) (7 -2).

  The radio base station (BTS1) selects a relay terminal (UE2) with a high priority from the relay terminal (UE) candidate list, and sets a path for the relay terminal (UE2) (7-3). . The radio base station (BTS1) adds a relay flag to the transmission signal from the radio terminal (MS1), and transmits the signal to the relay terminal (UE2) using an individual channel signal (7-4).

  The relay terminal (UE2) receives the above-mentioned signal transmitted from the radio base station (BTS1) and confirms that the signal is from the radio terminal (MS1) to the relay radio base station (BTS2). A relaying flag is added, and a transmission signal received from the wireless terminal (MS1) is transmitted to the wireless base station (BTS2) (7-5).

  The radio base station (BTS2) receives the above signal from the relay terminal (UE2) and determines whether the signal is a signal from the relay terminal (UE2) itself or a signal relayed by the relay terminal (UE2). The determination is made based on the added relay flag. In the case of a relayed signal, the relay target terminal (MS) list is updated and notified to the host device (RNC2) (7-6).

  With the above processing procedure, the transmission operation from the wireless terminal (MS1) is completed. As a result, the wireless terminal (MS1) under the control of the radio base station (BTS1) that is disconnected from the higher level apparatus (RNC1) is connected to the higher level apparatus (RNC2) via the relay terminal (UE2). It is handled as if the wireless terminal (MS1) is located under the wireless base station (BTS2).

  With reference to FIG. 8, a description will be given of an operation sequence of transmission of the wireless terminal (MS1) under the wireless base station (BTS1) whose line is disconnected from the host device. When a transmission event occurs from the wireless terminal (MS1) (8-1), the wireless terminal (MS1) establishes a wireless link with the wireless base station (BTS1) (8-2), and the wireless base station (BTS1) ) To transmit the data of the transmission signal (8-3).

  The radio base station (BTS1) judges whether or not the data transmitted from the radio terminal (MS1) is a signal to be relayed (8-4), and if it is a signal to be relayed, selects the relay terminal (UE) (8-5). Thereafter, the radio base station (BTS1) establishes a radio link with the relay terminal (UE2) (8-6). Then, a relay flag is assigned to the outgoing data from the wireless terminal (MS1) (8-7), and the data is transmitted to the relay terminal (UE2) (8-8).

  The relay terminal (UE2) determines whether or not the received data is a relay signal (8-9), and if it is a relay signal, holds the received data (8-10) and the radio base station (BTS1) Is temporarily disconnected (8-11). Thereafter, the relay terminal (UE2) adds a relay flag to the data (8-12), establishes a radio link with the relay radio base station (BTS2) (8-13), and The data is transmitted to the radio base station (BTS2) (8-14). The radio base station (BTS2) determines whether or not the received data is a relay signal (8-15), and if it is a relay signal, transmits the received data from which the relay flag has been removed to the host device (RNC2) ( 8-16).

  With reference to FIG. 9, a description will be given of an incoming procedure to a radio terminal under the control of a radio base station that is disconnected from a host device. The incoming call operation to the radio terminal (MS1) under the control of the radio base station (BTS1) disconnected from the host device (RNC1) is performed in the following procedure.

  Since the higher-level mobile communication network determines that the wireless terminal (MS1) is located under the wireless base station (BTS2) connected to the wireless network control device (RNC2), the wireless terminal (MS1) A call is made to the radio network control device (RNC2) when an incoming call is received (9-1).

  The radio network controller (RNC2) transmits a call signal for the radio terminal (MS1) to the subordinate radio base station (BTS2) (9-2). The radio base station (BTS2) refers to the relay target terminal (MS) list and determines whether or not the call target radio terminal (MS) is registered.

  When the call target radio terminal (MS) is registered in the relay target terminal (MS) list, the radio base station (BTS2) can relay to the relay destination radio base station (BTS1). Is selected from the relay target base station (BTS) list. Then, the radio base station (BTS2) transmits the paging signal with the relay flag added thereto to the relay terminal (UE2) using a dedicated channel signal. When the relay target wireless terminal (MS) is not registered, the wireless base station (BTS2) performs a normal call process (9-3).

  The relay terminal (UE2) under the radio base station (BTS2) receives the call signal with the relay flag added from the radio base station (BTS2), and sends the call signal with the relay flag to the relay destination radio. Relay to the base station (BTS1) using a dedicated channel signal (9-4).

  The radio base station (BTS1) receives the call signal with the relay flag added from the relay terminal (UE2), removes the relay flag from the received signal, and transmits the call signal to all subordinate areas ( 9-5). The wireless terminal (MS1) receives the call signal transmitted from the wireless base station (BTS1), establishes a path by returning a response signal, and receives incoming data (9-6). The incoming operation to the wireless terminal (MS1) is completed by the above processing procedure.

  Next, a procedure for updating the setting information of the relay terminal (UE) will be described with reference to FIG. The update operation of the setting information of the relay terminal (UE) is performed according to the following procedure. The relay terminal (UE) set to the relay mode 1 or the relay mode 2 checks the connection quality (reception level etc.) of the receivable radio base station (BTS) at regular intervals (10-1).

  Based on the above confirmation, the radio base station (BTS) that can be relayed and has the highest quality is checked (10-2). When the radio base station (BTS) is the current relay radio base station (BTS2), the relay terminal (UE2) again sends the current relay mode 1 or relay mode to the radio base station (BTS1). 2 relay attach (ATTACH) signal is transmitted (10-3).

  The radio base station (BTS1) receives the relay attach (ATTACH) signal from the relay terminal (UE2), and stores information on the relay terminal (UE2) registered in the relay terminal (UE) candidate list. Update according to the relay attach (ATTACH) signal (10-4).

  In the above check (10-2), when the wireless base station (BTS) that can be relayed and has the highest quality is a wireless base station (BTS3) other than the current wireless base station (BTS2) for relaying, The relay terminal (UE2) performs handover from the radio base station (BTS2) to the radio base station (BTS3) (10-5).

  The host apparatus (RNC) moves the management information of the radio terminal (MS1) under the relay terminal (UE2) and the radio base station (BTS1) to be relayed from the radio base station (BTS2) to the radio base station (BTS3). (10-6). After completion of the handover, the relay terminal (UE2) again transmits a relay attach (ATTACH) signal in the current relay mode 1 or relay mode 2 to the radio base station (BTS1) (10-7). .

  The radio base station (BTS1) receives a relay attach (ATTACH) signal from the relay terminal (UE2), and relays information on the relay terminal (UE2) registered in the relay terminal (UE) list. Update according to the ATTACH signal (10-8). The update operation of the setting information of the relay terminal (UE) is completed by the above processing procedure.

  Next, the operation at the time of failure recovery of the radio base station (BTS1) will be described with reference to FIG. The setting at the time of recovery from the communication failure between the radio base station (BTS1) and the host device (RNC1) is performed according to the following procedure. The radio base station (BTS1) detects the failure recovery of the line (Iub interface) with the higher level apparatus (RNC1) (11-1), and via the line (Iub interface) with the higher level apparatus (RNC1), The restart process is executed by receiving an instruction for the restart process from the RNC 1) (11-2).

  The wireless base station (BTS1) is reset by the setting information from the higher-level device (RNC1) after performing the restart process, and starts transmitting normal broadcast information to the wireless terminal (MS) (11-3). . When the type of the radio terminal (MS) under the control of the radio base station (BTS1) is a non-relay radio terminal (MS), the radio terminal (MS) receives normal notification information from the radio base station (BTS1). Is received, an attach (ATTACH) signal is transmitted, and the attach operation is redone (11-4).

  When the type of the radio terminal (MS) is a relay radio terminal (UE) and is a relay radio terminal (UE) in the relay mode 2, by receiving normal broadcast information from the radio base station (BTS1), The failure radio base station (BTS 2) is notified that it has become a relay radio terminal (UE) in relay mode 1 (11-5).

  When the type of the radio terminal (MS) is a relay radio terminal (UE) and is a relay terminal (UE) in the relay mode 0 or the relay mode 1, normal broadcast information is received from the radio base station (BTS1). As a result, the relay function is stopped and a transition is made to a normal wireless terminal (MS) (11-6). The above procedure completes the settings for failure recovery.

  FIG. 12 shows a configuration example of functional blocks of a wireless terminal that operates as a relay terminal. The wireless terminal includes a distribution coupling unit 12-1, a radio reception unit 12-2, a despreading demodulation unit 12-3, a CH separation unit 12-4, a call processing control unit 12-5, a data output unit or an accumulation unit 12-. 6, data storage unit 12-7, relay signal determination unit 12-8, relay data generation unit 12-9, data input unit 12-10, call processing control unit 12-11, CH multiplexing unit 12-12, modulation spreading unit 12-13 and a wireless transmission unit 12-14.

  The distribution / combining unit 12-1 has a function of distributing or combining a reception signal and a transmission signal transmitted / received by one transmission / reception antenna. The radio reception unit 12-2 has a function of receiving a radio signal transmitted from a radio base station. The despread demodulator 12-3 has a function of despreading and demodulating the signal code-spreaded by the radio base station.

  The CH separation unit 12-4 has a function of separating each channel signal such as a common channel signal and an individual channel signal. The call processing control unit 12-5 has a function of performing call setting processing based on an incoming signal or the like. The data output unit or storage unit 12-6 has a function of outputting call processing data output from the call processing control unit 12-5 or storing it in a nonvolatile memory or the like.

  The data storage unit 12-7 has a function of storing call processing data output from the call processing control unit 12-5 in a volatile memory or the like. The relay signal determination unit 12-8 has a function of determining whether or not the call processing data stored in the data storage unit 12-7 is a relay signal. The relay data generation unit 12-9 has a function of generating, based on the determination result of the relay signal determination unit 12-8, the relay data obtained by adding the relay flag to the call processing data stored in the data storage unit 12-7. Have.

  The data input unit 12-10 has a function of processing signal data input by the user of the wireless terminal. The call processing control unit 12-11 has a function of performing call setting processing such as outgoing call based on data transmitted from the data input unit 12-10 or the relay data generation unit 12-9. The CH multiplexing unit 12-12 has a function of multiplexing each channel signal such as a common channel signal and an individual channel signal. The modulation spreading unit 12-13 has a function of modulating the transmission signal and code spreading. The wireless transmission unit 12-14 has a function of transmitting a wireless signal to the wireless base station.

  FIG. 13 shows a configuration example of functional blocks of a radio base station that operates as a relay base station. The radio base station includes a distribution combiner 13-1, a radio receiver 13-2, a despread demodulator 13-3, a CH separator 13-4, a call processing controller 13-5, a data storage unit 13-7, Relay signal determination unit 13-8, relay data generation unit 13-9, call processing control unit 13-11, CH multiplexing unit 13-12, modulation spreading unit 13-13, radio transmission unit 13-14, radio resource control unit 13 -21, relay UE list creation unit 13-22, relay UE selection unit 13-23, transmission path IF unit 13-24, transmission path monitoring unit 13-25, emergency mode determination unit 13-26, and broadcast information transmission unit 13- 27.

  In the components shown in FIG. 13, those having functions similar to those shown in FIG. 12 (13-1 to 13-14) are not described repeatedly for the sake of brevity. The relay UE list creation unit 13-22 has a function of creating a relay terminal (UE) candidate list based on the information of the radio resource control unit 13-21.

  The relay UE selection unit 13-23 has a function of selecting a relay terminal (UE) based on the relay terminal (UE) candidate list created by the relay UE list creation unit 13-22. The call processing control unit 13-11 has a function of performing call setting processing such as outgoing call based on data transmitted from the relay data generation unit 13-9 and the relay UE selection unit 13-23.

  The transmission path IF unit 13-24 has an interface function of a line (transmission path) connected to the host device 13-30. The transmission line monitoring unit 13-25 has a function of monitoring the transmission line IF unit 13-24 and monitoring the occurrence and recovery of a communication failure with the host device 13-30.

  The emergency mode determination unit 13-26 has a function of determining the occurrence of an emergency mode in which the line with the host device 30 is disconnected based on the monitoring result of the transmission path monitoring unit 13-25. The notification information transmission unit 13-27 has a function of transmitting notification information indicating the emergency mode based on the determination result of the emergency mode determination unit 13-26. The call processing control unit 13-11 further has a function of performing call setting processing based on the notification information.

  FIG. 14 shows an example of a procedure for establishing a wireless link at the time of transmission from a wireless terminal. Establishment of a wireless link at the time of transmission from the wireless terminal (MS1) is performed according to the following procedure. The wireless base station (BTS1) receives a transmission request by a physical random access channel (PRACH) from the wireless terminal (MS1) (14-1).

  The radio base station (BTS1) transmits a downlink scrambling code (DL scrambling code), an uplink scrambling code (UL scrambling code), a downlink channelization code (DL channelization code), etc. to the radio terminal (MS1) The radio resource is taken out from the radio resource control unit 13-21 and a radio link is assigned (14-2).

  The radio base station (BTS1) stores outgoing data transmitted from the radio terminal (MS1) in the data storage unit 13-7 in the radio base station (BTS1) (14-3). The radio base station (BTS1) determines one relay terminal (UE) from the relay terminal (UE) list, and transmits a call signal to the relay terminal (UE) (14-4).

  The relay terminal (UE) transmits a paging response signal using the physical random access channel (PRACH) to the radio base station (BTS1) (14-5). The radio base station (BTS1) transmits a downlink scrambling code (DL scrambling code), an uplink scrambling code (UL scrambling code), and a downlink channelization code (DL channelization code) to the relay terminal (UE). ) And the like are taken out from the radio resource control unit 13-21, and a radio link is assigned (14-6).

  The radio base station (BTS1) adds a relay flag to the data stored in the data storage unit 13-7 in the radio base station (BTS1), and transmits the data to the relay terminal (UE) (14-7). With the above procedure, establishment of the wireless link at the time of outgoing call from the wireless terminal (MS1) is completed.

  FIG. 15 shows an example of a procedure for establishing a wireless link when an incoming call is received by the wireless terminal. The establishment of a wireless link when an incoming call to the wireless terminal (MS1) is received by the following procedure. A paging signal is transmitted from the radio base station (BTS2) connected to the host device to the subordinate radio terminal (MS) (15-1).

  The relay terminal (UE) under the radio base station (BTS2) receives the call signal described above, and then transmits a call request by the physical random access channel (PRACH) to the radio base station (BTS1) (15-2). ). The radio base station (BTS1) transmits a downlink scrambling code (DL Scrambling Code), an uplink scrambling code (UL Scrambling Code), and a downlink channelization code (DL Channelization) to the relay terminal (UE). The wireless resource such as Code) is taken out from the wireless resource control unit 13-21 and assigned to assign a wireless link (15-3).

  After receiving the incoming data from the relay terminal (UE), the wireless base station (BTS1) accumulates the incoming data in the data storage unit 13-7 in the wireless base station (BTS1) (15-4). The radio base station (BTS1) recognizes the paging signal from the accumulated data and transmits the paging signal to the radio terminal (MS1) (15-5).

  The wireless terminal (MS1) recognizes that the call signal is a call signal addressed to itself, and transmits a call response signal to the wireless base station (BTS1) (15-6). Upon reception of the paging response signal from the wireless terminal (MS), the wireless base station (BTS1) transmits a downlink scrambling code (DL scrambling code), an uplink scrambling code (UL scrambling code) to the wireless terminal (MS1). Code) and a downlink channelization code (DL Channelization Code) and the like are extracted from the radio resource control unit 13-21, and a radio link is assigned (15-7).

  The radio base station (BTS1) transmits a call response signal from the radio terminal (MS1) to the relay terminal (UE) using the radio link of the relay terminal (UE) that has already been set (15). -8). After receiving the call response signal from the radio base station (BTS1), the relay terminal (UE) transmits the call response signal to the radio base station (BTS2) through the physical random access channel (PRACH) (15-9). .

  The radio base station (BTS2) establishes a radio link by a call response signal from the relay terminal (UE) (15-10). With the above procedure, establishment of a wireless link at the time of incoming to the wireless terminal (MS1) is completed.

MS1, MS2 Wireless terminal BTS1, BTS2, BTS3 Wireless base station RNC1, RNC2, RNC3 Host device (wireless network control device)
UE2, UE3, UE4 relay terminal

Claims (6)

From the first radio base station whose line connection with the host apparatus is disconnected, a common control signal indicating the line disconnection state with the host apparatus is transmitted to the radio terminal located in the subordinate radio area, and the first radio base station A first step of setting a wireless terminal located in the wireless area of both the wireless base station and the second wireless base station adjacent to the first wireless base station as a relay terminal;
Transmission / reception data transmitted / received between a radio terminal located in the radio area of the first radio base station and the first radio base station is transmitted between the first radio base station and the relay terminal. And a second step of giving and receiving a relay flag between the relay terminal and the second radio base station, respectively,
A third step of transmitting / receiving the transmission / reception data from which the relay flag has been removed from the second radio base station to / from a host device of the second radio base station;
A wireless communication path relay method comprising: From the first radio base station whose line connection with the host apparatus is disconnected, a common control signal indicating the line disconnection state with the host apparatus is transmitted to the radio terminal located in the subordinate radio area, and the first radio base station A first step of setting a wireless terminal located in a wireless area of both the wireless base station and the second wireless base station adjacent to the first wireless base station as a first relay terminal;
Transmission / reception data transmitted / received between a radio terminal located in a radio area of the first radio base station and the first radio base station is transmitted to the first radio base station and the first relay terminal. A second step of giving and receiving a relay flag between relay terminals and radio base stations connected in multiple stages including:
The relay flag is removed at the last radio base station of the radio communication path between the relay terminal and the radio base station connected in multiple stages, and the transmission / reception data from which the relay flag has been removed is transmitted to the last radio base station. A third step of transmitting / receiving to / from a host device;
A wireless communication path relay method comprising: A line disconnection notification means for notifying a wireless terminal located in a subordinate wireless area by a common control signal of a line disconnection state with a host device;
A relay terminal is selected from the wireless terminals that have received the relay mode information transmitted from the wireless terminal and indicating whether or not the wireless terminal is relayable, and transmitted the relay mode information indicating that the wireless terminal is relayable. Relay terminal setting means for establishing a wireless link with the relay terminal;
Transmission / reception data transmitted / received to / from a wireless terminal located in the subordinate wireless area is transmitted / received to / from the relay terminal with a relay flag, and from the data to which the relay flag is attached, Transmission / reception data relay means for transmitting / receiving the transmission / reception data from which the relay flag is removed to / from a higher-level device;
A radio base station apparatus comprising: The line disconnection notification means indicates whether relaying is not possible, direct relaying is possible via a host device of the radio base station, or relaying is indirectly possible via a host device of another adjacent radio base station. Notify line disconnection mode information,
The relay mode information notified from the wireless terminal cannot be relayed, can be relayed directly through a higher-level device of the wireless base station where the wireless terminal is located, or can be relayed indirectly through another relay terminal Show information about which
The radio base station apparatus according to claim 3, further comprising: a relay mode setting unit that updates information on the line disconnection mode based on relay mode information notified from the radio terminal. A common control signal transmitted from the first radio base station and indicating a line disconnection state with the host device is received, and a common control signal received from a second radio base station adjacent to the first radio base station is received. A relay mode notification means for notifying the first and second radio base stations of relay mode information indicating that the radio terminal is a relayable radio terminal;
Transmission / reception data transmitted / received by a wireless terminal located in a wireless area under the first wireless base station, the data transmitted with a relay flag added from the first wireless base station, Transmission / reception data relay means for relaying data transmitted from the second radio base station to the first radio base station.
A wireless terminal comprising: The common control signal received from the second radio base station cannot be relayed, can be relayed directly via a host device of the radio base station, or indirectly via a host device of another adjacent radio base station. Including information on the line disconnection mode indicating which of the relays is possible,
The relay mode notification means can not relay based on the line disconnection mode, can be relayed directly through a higher-level device of the wireless base station where the wireless terminal is located, or indirectly relayed through another relay terminal The wireless terminal according to claim 5, wherein relay mode information indicating information indicating which is possible is notified.

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