JP2010028667A - Radio communication system and system switching method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a radio communication system etc., that performs system switching without packet loss or momentary breaking, by providing a radio communication system which is reduced in cost, and to provide a system switching method. <P>SOLUTION: The radio communication system includes a plurality of radio base station devices and a radio base station controller which controls the respective radio base station devices. One of the plurality of radio base station devices is a master radio base station device, which is connected to other radio base station device except the master radio base station device in one-to-(n) relation (n: an integer equal to or greater than 1), and also connected to the radio base station controller. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a wireless communication system and a system switching method.

  In recent years, wireless base station devices are installed in various places, both indoors and outdoors. For example, by installing a plurality of radio base station devices in one installation location, there is a device that covers a wider area and suppresses installation cost and operation cost as much as possible.

  FIG. 12 is a diagram illustrating a configuration example of such a conventional wireless communication system 200. The radio communication system 200 includes a radio base station control management device (hereinafter “network side device”) 50 and a plurality of radio base station devices 100-1 to 100-5. The plurality of radio base station apparatuses 100-1 to 100-5 are connected to the network side apparatus 50 by optical fibers.

  FIG. 13 is a diagram illustrating another configuration example of the conventional wireless communication system 200. An optical fiber terminator 60 is provided in the same building as the radio base station devices 100-1 to 100-5 or in a nearby location, and the terminator 60 is connected to the network side device 50 by a single optical fiber.

In addition, there exists patent document 1 shown below about a radio | wireless communications system.
JP 2007-267267 A

  However, in the radio communication system 200 shown in FIG. 12, each of the radio base station apparatuses 100-1 to 100-5 must be connected to the network side apparatus 50 by an expensive optical fiber. A lot of costs such as costs.

  On the other hand, in the radio communication system 200 shown in FIG. 13, the radio base station apparatuses 100-1 to 100-5 are connected to the network side apparatus 50 by one optical fiber via the optical fiber termination apparatus 60. Compared to the case, the cost can be reduced. However, since the installation cost and operation cost of the optical fiber termination device 60 are required, the cost cannot be reduced. Further, when a problem occurs in the optical fiber termination device 60, communication of all the radio base station devices 100-1 to 100-5 is interrupted. Such a situation can be prevented by a device having a redundant function, but the cost increases as a result of the operation of such a device.

  Accordingly, an object is to provide a wireless communication system and a system switching method with reduced costs.

  Another object is to provide a wireless communication system or the like that can switch a system without packet loss without instantaneous loss.

  According to an aspect, a wireless communication system includes a plurality of wireless base station devices and a wireless base station control device that controls each of the wireless base station devices, and any one of the plurality of wireless base station devices. One is a master radio base station apparatus, and the master radio base station apparatus is connected to the other radio base station apparatus other than the master radio base station apparatus in a 1: n ratio (n is an integer of 1 or more). , Connected to the radio base station controller.

  According to another aspect, in a wireless communication system, the wireless communication system includes a plurality of wireless base station devices and a wireless base station control device that controls each of the wireless base station devices, and among the plurality of wireless base station devices, Any one is a master radio base station apparatus, and one of the plurality of radio base station apparatuses other than the master radio base station is a slave radio base station apparatus, and the master radio base station apparatus and The slave radio base station apparatus is connected to the radio base station control apparatus and has a 1-to-n relationship (n is 1) with the radio base station apparatus under the control other than the master radio base station apparatus and the slave radio base station apparatus. (Integer above).

  Further, according to another aspect, in a system switching method in a radio communication system having a plurality of radio base station devices and a radio base station control device that controls the radio base station devices, the plurality of radio base station devices The master radio base station apparatus which is any one of the radio base station apparatuses communicates with the connected radio base station apparatus and the subordinate radio base station connected in a 1: n relationship (n is an integer of 1 or more). When the mobile radio base station apparatus generates a system switching packet, the master radio base station apparatus is a slave radio base station apparatus that is any one of the plurality of radio base stations other than the master radio base station apparatus The slave radio base station loses a packet to be transmitted from the master radio base station based on the system switch packet. Rukoto without transmitting the packet to the radio base station apparatus of the subordinate connected by connected the radio base station controller and a pair n.

  A wireless communication system and a system switching method with reduced costs can be provided. In addition, it is possible to provide a wireless communication system or the like that can switch the system without packet loss without instantaneous loss.

  Hereinafter, the best mode for carrying out the invention will be described with reference to the drawings.

  FIG. 1 is a diagram illustrating a configuration example of a wireless communication system 1. The radio communication system 1 includes a plurality of radio base station devices (hereinafter “radio base stations”) 10-1 to 10-5 and a network side device 50.

  Each of the radio base stations 10-1 to 10-5 performs radio communication with the terminal devices under the radio base stations 10-1 to 10-5. A plurality of radio base stations 10-1 to 10-5 constitute a radio base station having a plurality of sectors.

  Any one of the plurality of radio base stations 10-1 to 10-5 is a master radio base station apparatus (hereinafter referred to as “master radio base station”) 10-1.

  The master radio base station 10-1 is connected to the network side device 50 by an optical fiber capable of long-distance transmission, and performs communication by IP (Internet Protocol). The master radio base station 10-1 is connected to the subordinate radio base stations 10-2 to 10-5 by, for example, a twisted pair cable. The master radio base station 10-1 outputs a packet from the subordinate radio base stations 10-2 to 10-5 to the network side device 50, or a packet from the network side device 50 to the subordinate radio base station 10-2. Output to -10-5. For this reason, the master radio base station 10-1 includes switching therein. Details will be described later.

  The network side device 50 is a radio base station control device that controls and manages a plurality of radio base stations 100-1 to 100-5, and is, for example, an ASN-GW (Access Service Network-Gateway). The network device 50 is connected to the Internet and communicates with other devices.

  Packet transfer in the wireless communication system 1 is as follows. That is, in the downstream direction (direction from the network side device 50 to each of the radio base stations 10-1 to 10-5), the network side device 50 transmits an IP packet.

  The master radio base station 10-1 receives the IP packet and transmits it to a terminal device under its own station by a switch such as a MAC layer switch, or transfers it to the subordinate radio base stations 10-2 to 10-5. The subordinate radio base stations 10-2 to 10-5 perform signal processing on the IP packet and transmit it to the subordinate terminal apparatus.

  On the other hand, in the uplink direction (direction from each radio base station 10-1 to 10-5 to the network side device 50), the subordinate radio base stations 10-2 to 10-5 receive signals transmitted from the terminal devices, respectively. Then, it is converted into an IP packet and transmitted to the master radio base station 10-1. The master radio base station 10-1 also converts a signal from a terminal device under its control into an IP packet.

  The master radio base station 10-1 transfers the IP packet to the network side device 50 by, for example, a MAC layer switch.

  As described above, the radio communication system 1 shown in FIG. 1 includes a plurality of radio base station apparatuses 10-2 to 10-5 and a network-side apparatus 50 that are in a one-to-n relationship (n is 1) via the master radio base station 10-1. Connected by the above integer). For this reason, the optical fibers are combined into one, and the cost can be reduced as compared with the case where a plurality of optical fibers are installed. In addition, since the wireless communication system 1 does not require a special device such as an optical fiber terminating device, the cost can be reduced as compared with the case where such a device is installed.

  FIG. 2 is a diagram illustrating another configuration example of the wireless communication system 1. Any one of the radio base stations 10-2 to 10-6 other than the master radio base station 10-1 is defined as a slave radio base station 10-2.

  The slave radio base station 10-2 is connected to the network side device 50 and connected to the subordinate radio base station devices 10-3 to 10-6 in the same manner as the master radio base station 10-1, and is connected in a 1: n connection. The The slave radio base station 10-2 is also connected to the master radio base station 10-1. The connection between each of the radio base stations 10-1 to 10-6 is made by, for example, an inexpensive twisted pair cable.

  The slave radio base station 10-2 includes a switch such as a MAC layer switch in the same manner as the master radio base station 10-1. Details thereof will be described later.

  However, during normal operation, the slave radio base station 10-2 logically blocks the subordinate radio base stations 10-3 to 10-6 side ports, and the radio base stations 10-3 to 10-6 are Although the packet is received, the packet is discarded. The slave radio base station 10-2 also logically blocks the port on the network side device 50 side, and receives the packet from the network side device 50, but discards the packet.

  Normal packet transfer is performed as follows. That is, in the downlink direction, the network side device 50 transmits the same packet to the master radio base station 10-1 and the slave radio base station 10-2.

  The master radio base station 10-1 switches the received packet and transmits it to the subordinate radio base stations 10-3 to 10-6, the slave radio base station 10-2, or a terminal device under its own station.

  The subordinate radio base stations 10-3 to 10-6 perform signal processing on the received packet from the master radio base station 10-1, and transmit it to the subordinate terminal apparatus as a radio signal.

  On the other hand, the slave radio base station 10-2 receives the received packet from the master radio base station 10-1, and when the received packet is a packet addressed to the subordinate radio base stations 10-3 to 10-6, Since the ports on the stations 10-3 to 10-6 side are logically blocked, the packet is discarded. Therefore, the slave radio base station 10-2 does not redundantly transmit packets to the subordinate radio base stations 10-3 to 10-6. However, when the slave radio base station 10-2 is a packet addressed to itself, the slave radio base station 10-2 converts the packet into a radio signal and transmits the radio signal to a subordinate terminal device.

  The upstream direction operates as follows. That is, each of the radio base stations 10-3 to 10-6 receives a signal from a terminal device under its control, converts it into a packet, and transmits it to the master radio base station 10-1 and the slave radio base station 10-2.

  The master radio base station 10-1 transfers the packet from the subordinate radio base stations 10-3 to 10-6 or the packet from the terminal device under its own station to the network side device 50 by switching.

  The slave radio base station 10-2 receives the packet from the subordinate radio base stations 10-3 to 10-6, but discards the packet because the port is blocked. Thereby, the network side apparatus 50 does not receive the same packet from the master radio base station 10-1 and the slave radio base station 10-2 redundantly.

  The slave radio base station 10-2 transfers the packet from the terminal device under its control to the master radio base station 10-1, and the master radio base station 10-1 transmits the packet to the network side device 50.

  FIG. 3 is a diagram illustrating an operation example when a problem occurs in the master radio base station 10-1, such as an optical fiber being cut, an optical module being broken, or an alarm in the apparatus being generated.

  When a problem such as the inability to communicate with the master radio base station 10-1 occurs, the radio communication system 1 performs system switching. Therefore, the master radio base station 10-1 transmits a system switching packet to the slave radio base station 10-2. Here, the system switching packet is, for example, a TTC (Telecommunication Technology Committee) standard TS-100 (Optical Subscriber Line Interface Standard) packet or the like.

  At this time, the master radio base station 10-1 logically blocks the ports on the network side device 50 side and the subordinate radio base stations 10-3 to 10-6 side. The master radio base station 10-1 newly operates as a slave radio base station.

  When the slave radio base station 10-2 receives the system switching packet, the slave radio base station 10-2 opens the ports of the subordinate radio base stations 10-3 to 10-6 and the network side device 50 when triggered. The slave radio base station 10-2 newly operates as a master radio base station.

  In such switching, it is desirable that the master radio base station 10-1 and the slave radio base station 10-2 switch the system without interruption without packet loss.

  Hereinafter, the configuration of each of the radio base stations 10-1 to 10-6 will be described, and then the operation of the system switching process will be described.

  4 and 5 are diagrams illustrating configuration examples of the master radio base station 10-1 and the slave radio base station 10-2. The master radio base station 10-1 and the slave radio base station 10-2 have the same configuration. FIG. 4 is a diagram showing a configuration example of the master radio base station and slave radio base stations 10-1 and 10-2 (hereinafter referred to as “master / slave radio base station 10”) in the uplink direction.

  The master / slave radio base station 10 includes an own station main signal / control signal packet buffer (hereinafter referred to as a “packet buffer”) 11-1, individual buffers 11-3 to 11-6, a MAC layer switch 12, and a cutoff time. A stamp determination unit 13, a maintenance packet processing & packet read control unit (hereinafter “read control unit”) 14, and a CPU 15 are provided.

  The packet buffer 11-1 temporarily stores packets from terminal devices under the master / slave radio base station 10. For example, a main signal, a control signal, and the like from the terminal device are converted into packets in another processing unit (or CPU 15) and stored in the packet buffer 11-1. At this time, the packet is stored in the packet buffer 11-1 with time stamp information and MAC address (source address and destination address) added under the control of the CPU 15. The packet stored in the packet buffer 11-1 is appropriately read under the control of the CPU 15 and output to the MAC layer switch 12.

  The individual buffers 11-3 to 11-6 temporarily store packets from the subordinate radio base stations 10-3 to 10-6, respectively. The temporarily stored packet is appropriately read under the control of the read control unit 14 and output to the MAC layer switch 12.

  Whether the master / slave radio base station 10 is the master radio base station 10-1 or the slave radio base station 10-2, the individual buffers 11-3 to 11-6 are stored in the subordinate radio base stations 10-3 to 10-3. The packet from 10-6 is temporarily stored. However, although the packets stored in the individual buffers 11-3 to 11-4 of the slave radio base station 10-2 are read by the read control unit 14, they are discarded.

  The MAC layer switch 12 switches the packets from the packet buffer 11-1 and the individual buffers 11-3 to 11-6 under the control of the read control unit 14 and sequentially outputs the packets to the cutoff time stamp determination unit 13.

  The blocking time stamp determination unit 13 reads the time stamp information of the packet from the MAC layer switch 12, and removes the time stamp information from the packet and transmits it to the network side device 50. Since the cutoff time stamp determination unit 13 reads the time stamp information of the packet most recently transmitted to the network side device 50, the time stamp of the transmitted packet immediately before the master radio base station 10-1 performs system switching (immediately before the cutoff). Information can be read out.

  The read control unit 14 performs read control of the packets stored in the packet buffer 11-1 and the individual buffers 11-3 to 11-6, and reads time stamp information of the packets. Further, the read control unit 14 receives the time stamp information of the transmission packet immediately before the blocking from the blocking time stamp determination unit 13. Further, the read control unit 14 controls switching of the MAC layer switch 12.

  When the master / slave radio base station 10 is the master radio base station 10-1, the read control unit 14 generates a system switching packet for switching the system under the control of the CPU 15, and determines a cutoff time stamp in the system switching packet. The time stamp information from the unit 13 is added and transmitted to the slave radio base station 10-2.

  When the packet having the time stamp information next to the time stamp information added to the system switching packet is stored in the packet buffer 11-1, the read control unit 14 reads the packet and sets the MAC layer switch 12 To the slave radio base station 10-2.

  When the master / slave radio base station 10 is the slave radio base station 10-2, the read control unit 14 receives a system switching packet from the master radio base station 10-1. Under the control of the CPU 15, the read control unit 14 reads a packet having time stamp information next to the time stamp information added to the system switching packet from the packet buffer 11-1 and the individual buffers 11-3 to 11-6. In addition, when the read control unit 14 sequentially receives packets from the master radio base station 10-1, the read control unit 14 outputs the packets to the MAC layer switch 12, and next to the packet (one or a plurality of packets) (such as +1). Packets having the time stamp information are read from the individual buffers 11-3 to 11-6.

  When the master / slave radio base station 10 is the master radio base station 10-1, the CPU 15 detects a problem such as an optical fiber cut and outputs a control signal for system switching to the read control unit 14.

  When the master / slave radio base station 10 is the slave radio base station 10-2, the CPU 15 receives the system switching packet received by the read control unit 14, recognizes the system switching, and the time added to the system switching packet. The read control unit 14 is controlled to acquire a packet having time stamp information next to the stamp information.

  FIG. 5 is a diagram illustrating a configuration example of the master / slave radio base station 10 in the downlink direction. The master / slave radio base station 10 further includes a MAC DA FCS monitoring unit (hereinafter, “monitoring unit”) 16, a table 17, and DA individual buffers 18-1 to 18-4.

  The monitoring unit 16 reads a destination address (DA) for the packet from the network side device 50, and sends the packet to each DA individual buffer 18-1 to 18-4 provided for each address. Output.

  The monitoring unit 16 reads the FCS value included in the packet and outputs it to the table 17. Downstream packets do not always include time stamps like upstream packets. Since the received packet itself is an IP packet, the monitoring unit 16 monitors the FCS value on the MAC frame to identify each packet. FIG. 6 is a diagram illustrating an example of an IP packet. The FCS uses CRC-32, and it is unlikely that packets having the same FCS value stochastically exist.

  The table 17 holds FCS values in the order of packet reception. 7A shows an example of the table 17 in the master radio base station 10-1, and FIG. 7B shows an example of the table 17 in the slave radio base station 10-2. As shown in these figures, FCS values are stored in the order of packet reception.

  Each DA individual buffer 18-1 to 18-4 temporarily stores a packet for each DA. For example, each DA individual buffer 18-1 to 18-4 temporarily stores a packet for each of the subordinate radio base stations 10-3 to 10-6 and the own station.

  When the master / slave radio base station 10 is the master radio base station 10-1, the read control unit 14 notifies the MAC layer switch 12 of each DA individual buffer when a system switching control signal is notified from the CPU 15. An instruction is given to discard the packet read from 18-1 to 18-4, and the port on the network side device 50 and the subordinate base stations 10-3 to 10-6 are blocked. At this time, the read control unit 14 reads the FCS value of the last received packet from the table 17 (or individual DA individual buffers 18-1 to 18-4), adds it to the system switching packet, and adds it to the slave radio base station 10- 2 to send.

  When the master / slave radio base station 10 is the slave radio base station 10-2, the read control unit 14 retrieves the FCS value of the system switching packet, searches the table 17, and obtains the FCS value of the packet number next to the FCS value. read out. Then, the read control unit 14 reads out the packet having the read FCS value from each DA individual buffer 18-1 to 18-4 and outputs it to the MAC layer switch 12. Further, in order to open the ports of the wireless base stations 10-3 to 10-6 subordinate to the network side device 50, the read control unit 14 switches the read packets to the MAC layer switch 12 and outputs them. Control.

  FIG. 6 is a diagram illustrating a configuration example of subordinate radio base stations 10-3 to 10-6. The subordinate radio base stations 10-3 to 10-6 include a packet buffer 11-1, a MAC layer switch 12, and a CPU 15.

  The CPU 15 controls the storage and reading of packets to and from the packet buffer 11-1. In the upstream direction, the CPU 15 adds time stamp information to the packet stored in the packet buffer 11-1.

  The MAC layer switch 12 transmits a packet to the master radio base station 10-1 and the slave radio base station 10-2 under the control of the CPU 15, or from the master radio base station 10-1 or the slave radio base station 10-2. Are output to the bucket buffer 11-1.

  FIG. 9 is a sequence diagram illustrating an example of the system switching process.

  If any problem occurs in the master radio base station 10-1, such as a broken optical fiber, an optical module in the device, or an alarm in the device (S20), the read control unit 14 of the master radio base station 10-1 switches the system. The packet is transmitted to the slave radio base station 10-2 (S21). The read control unit 14 adds the time stamp information (counter information) of the last transmitted packet for the upstream packet, and transmits the FCS value of the last received packet for the downstream packet by adding it to the system switching packet. .

  The CPU 15 of the slave radio base station 10-2 recognizes the system switching by receiving the system switching packet (S30).

  On the other hand, the read control unit 14 of the master radio base station 10-1 blocks the transmission-side port (S22). That is, the read control unit 14 stops the transfer of packets received from the subordinate radio base stations 10-3 to 10-6 from the individual buffers 11-3 to 11-6 to the MAC layer switch 12, and the individual buffer 11 -Forcibly discard packets read from -3 to 11-6.

  Next, the read control unit 14 blocks the port on the receiving side (S23). That is, the read control unit 14 stops the transfer from the DA individual buffers 18-1 to 18-4 to the MAC layer switch 12, and forcibly discards the packets read from the DA individual buffers 18-1 to 18-4. To do.

  The master radio base station 10-1 operates as a slave radio base station by blocking the ports on the network side device 50 side and the subordinate radio base stations 10-3 to 10-6 by the processes of S22 and S23 (S24). ).

  On the other hand, the slave radio base station 10-2 that has recognized the system switching opens the transmission-side port by the read control unit 14 (S31). That is, the read control unit 14 reads the final transmission counter value (final transmission time stamp information) from the system switching packet, and transmits the packet having the counter value next to the counter value to the packet buffer 11-1 and the individual buffers 11-3. Extract from 11-6. Then, under the control of the read control unit 14, the MAC layer switch 12 starts transmitting the packet to the network side device 50 (S31).

  Next, the read control unit 14 opens the port on the receiving side (S32). That is, the read control unit 14 reads the final FCS value from the system switching packet, and reads the FCS value of the packet number next to the packet number corresponding to the final FCS value with reference to the table 17. Then, the read control unit 14 reads out the packet having the FCS value from each DA individual buffer 18-1 to 18-4, and transmits the packet to the subordinate radio base stations 10-3 to 10-6 and the terminal device under its own station. To start.

  The slave radio base station 10-2 opens the ports on the network side device 50 side and the subordinate radio base stations 10-3 to 10-6 side by the processing of S31 and S32, and newly operates as a master radio base station (S33).

  The radio communication system 1 of the present embodiment switches systems when any problem occurs in the master radio base station 10-1, and the slave radio base station 10-2 newly operates as a master radio base station. Even in this case, compared with the case where each of the radio base stations 10-1 to 10-6 connects the network side device 50 and the optical fiber, the number of optical fibers connected can be reduced, and the cost can be reduced. In addition, since no special device such as a termination device is required, cost reduction can be achieved. Further, the master radio base station 10-1 adds information identifying the packet last transmitted to the network side device 50 or the packet received from the network side device 50 at the time of system switchover to the system switch packet, and serves as a slave radio base station. Send to 10-2. Therefore, since the slave radio base station 10-2 can transmit the packet received so far based on the identification information, the radio communication system 1 can switch the system without interruption without packet loss.

  In the example described above, the master / slave radio base station 10 uses the table 17 to hold the FCS value. In this case, it is desirable that the master radio base station 10-1 and the slave radio base station 10-2 have the same contents (synchronize) at the same time with respect to the table 17. This is because the order of the packets may be reversed or the packets may be lost on the IP network side, and the packets are accurately transmitted without interruption during system switching.

  Therefore, the radio communication system 1 stores the contents of the table 17 of the master radio base station 10-1 in a system switching packet, and periodically transmits the contents to the slave radio base station 10-2, so that the master radio base station 10-1 And the contents of the table 17 are synchronized between the slave radio base station 10-2.

  In this case, the system switching packet (hereinafter referred to as “synchronization packet”) is distinguished from the packet for switching the system described above, for example, an identification flag is provided in the packet, or table contents are stored in the packet. You may make it identify by whether or not.

  FIG. 10 is a diagram illustrating how the synchronization packet is transmitted from the master radio base station 10-1 to the slave radio base station 10-2 in the radio communication system 1.

  FIG. 11 is a flowchart showing an example of the synchronization processing of the table 17.

  The read controller 14 of the slave radio base station 10-2 starts processing upon reception of the synchronization packet (S10).

  The read control unit 14 searches the table 17 with the first FCS value among the tables included in the received synchronization packet (S11).

  When they match (Y in S12), the read control unit 14 determines whether or not the FCS value of the next packet number in the table included in the synchronization packet matches the FCS value of the next packet number in the table 17 ( S14).

  When they coincide with each other (Y in S14), the read control unit 14 continuously compares the FCS values one after another and compares them to the last FCS value (S16).

  When all match as a result (Y in S16), the table 17 is completely synchronized with the table 17 of the master radio base station 10-1 (S17). Then, the read control unit 14 ends the series of processes (S18).

  On the other hand, when there is no match in the FCS head value (N in S12), the read control unit 14 searches again with the next FCS value until it matches.

  Further, when the FCS values do not match in the middle (N in S14, N in S16), the read control unit 14 changes the order of the table 17 assuming that the order is reversed in the received packet (S15).

  For example, the table 17 of the master radio base station 10-1 shown in FIG. 7A and the table 17 of the slave radio base station 10-2 shown in FIG. 7B are packet numbers “7” and “8”. The order is different. Therefore, in such a case, the read control unit 14 of the slave radio base station 10-2 changes the order of the packet numbers and holds the table 17.

  As described above, the radio communication system 1 synchronizes the table 17 of the master radio base station 10-1 and the slave radio base station 10-2, so that the order of the packets can be accurately and without being reversed. Packets can be transmitted to the subordinate radio base stations 10-3 to 10-6 without interruption.

  The above is summarized as an appendix.

(Appendix 1)
In a wireless communication system,
A plurality of radio base station devices;
A radio base station control device that controls each of the radio base station devices,
Among the plurality of radio base station devices, any one is a master radio base station device,
The master radio base station apparatus is connected to the radio base station apparatus other than the master radio base station apparatus in a 1 to n (n is an integer of 1 or more) and to the radio base station control apparatus. A wireless communication system.

(Appendix 2)
In a wireless communication system,
A plurality of radio base station devices;
A radio base station control device that controls each of the radio base station devices,
Among the plurality of radio base station devices, any one is a master radio base station device,
Among the plurality of radio base station devices other than the master radio base station, any one is a slave radio base station device,
The master radio base station apparatus and the slave radio base station apparatus are connected to the radio base station control apparatus, and the radio base station apparatus under control other than the master radio base station apparatus and the slave radio base station apparatus A wireless communication system characterized by being connected in a 1-to-n relationship (n is an integer of 1 or more).

(Appendix 3)
When the master radio base station apparatus cannot communicate with the radio base station control apparatus and the subordinate radio base station apparatus, a system switch packet is transmitted to the master radio base station apparatus,
The slave radio base station apparatus, based on the system switching packet, without losing a packet to be transmitted from the master radio base station apparatus, the subordinate radio base station apparatus or the radio base station control apparatus The wireless communication system according to attachment 2, wherein the wireless communication system transmits a packet.

(Appendix 4)
The master radio base station apparatus adds the time stamp information or FCS information of the last packet transmitted / received before the communication becomes impossible to the system switch packet, and transmits the system switch packet. The wireless communication system described.

(Appendix 5)
The wireless communication system according to supplementary note 3, wherein the slave radio base station device blocks ports on the subordinate radio base station device side and the radio base station control device side.

(Appendix 6)
The master radio base station device, when the communication is not possible, shuts off the subordinate radio base station device side and the port on the radio base station device side,
The wireless communication system according to appendix 5, wherein the slave radio base station device opens the subordinate radio base station side and the port on the radio base station device side when receiving the system switching packet.

(Appendix 7)
3. The radio communication system according to appendix 2, wherein the subordinate radio base station apparatus and the slave radio base station apparatus add time stamp information to the packet and transmit the packet to the master radio base station apparatus.

(Appendix 8)
The slave radio base station device includes a storage unit that stores the packet received from the subordinate radio base station device having the time stamp information,
The slave radio base station apparatus reads out a packet having time stamp information next to the time stamp information from the storage unit based on the time stamp information added to the system switching packet, and the radio base station control apparatus The wireless communication system according to appendix 4, wherein the packet to be transmitted from the master radio base station apparatus is transmitted to the radio base station control apparatus without being lost.

(Appendix 9)
The slave radio base station device includes a storage unit that stores the packet received from the radio base station control device having the FCS value,
The slave radio base station apparatus reads out the packet having the FCS value received next to the FCS value from the storage unit based on the FCS value added to the switching packet, and the subordinate radio base station apparatus The wireless communication system according to appendix 4, wherein the packet to be transmitted from the master radio base station apparatus is transmitted to the subordinate radio base station control apparatus without loss.

(Appendix 10)
The slave radio base station device includes a table that stores the FCS values in the order of reception of the packets,
The slave radio base station apparatus reads the packet from the storage unit by searching for a packet having an FCS value received next to the FCS value added to the switching packet based on the table. The wireless communication system according to appendix 9.

(Appendix 11)
The master radio base station apparatus includes a table that stores the FCS values in the order in which packets having the FCS values are received from the radio base station control apparatus, and periodically stores information in the table in the slave radio base station apparatus. The wireless communication system according to appendix 4, wherein transmission is performed.

(Appendix 12)
In a system switching method in a radio communication system having a plurality of radio base station apparatuses and a radio base station control apparatus that controls the radio base station apparatus,
The master radio base station apparatus that is one of the plurality of radio base station apparatuses is connected to the connected radio base station apparatus in a 1-to-n relationship (n is an integer of 1 or more). When communication with the subordinate radio base station is not possible, a system switching packet is generated,
The master radio base station apparatus transmits the system switch packet to a slave radio base station apparatus that is one of the plurality of radio base stations other than the master radio base station apparatus,
The slave radio base station is connected to the connected radio base station controller and the subordinate connected in a 1: n basis without losing a packet to be transmitted from the master radio base station based on a system switching packet. Transmitting the packet to the wireless base station device of
A system switching method characterized by that.

FIG. 1 is a diagram illustrating a configuration example of a wireless communication system. FIG. 2 is a diagram illustrating another configuration example of the wireless communication system. FIG. 3 is a diagram illustrating a configuration example of a wireless communication system at the time of system switching. FIG. 4 is a diagram illustrating a configuration example of a master / slave radio base station. FIG. 5 is a diagram illustrating a configuration example of a master / slave radio base station. FIG. 6 is a diagram illustrating an example of an IP packet. FIG. 7A and FIG. 7B are diagrams showing examples of tables. FIG. 8 is a diagram illustrating a configuration example of a subordinate radio base station. FIG. 9 is a flowchart illustrating an example of the system switching process. FIG. 10 is a diagram illustrating a configuration example of a wireless communication system when a synchronization packet is transmitted. FIG. 11 is a flowchart showing an example of table synchronization processing. FIG. 12 is a diagram illustrating a configuration example of a conventional wireless communication system. FIG. 13 is a diagram illustrating a configuration example of a conventional wireless communication system.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Radio | wireless communications system, 10 Radio base station apparatus, 10-1 Master radio base station apparatus, 10-2 Slave radio base station apparatus, 10-3 to 10-6 Subordinate radio base station apparatus, 11-1 Packet buffer, 11 -3 to 11-6 Individual buffer, 12 MAC layer switch, 13 Blocking time stamp determination unit, 14 Maintenance packet processing & packet read control unit (read control unit), 15 CPU, 16 MAC per FC DA FCS monitoring unit (monitoring unit) , 17 tables, 18-1 to 18-4 Individual buffers for each DA, 50 Network side device

Claims (5)

In a wireless communication system,
A plurality of radio base station devices;
A radio base station control device that controls each of the radio base station devices,
Among the plurality of radio base station devices, any one is a master radio base station device,
The master radio base station apparatus is connected to the radio base station apparatus other than the master radio base station apparatus in a 1 to n (n is an integer of 1 or more) and to the radio base station control apparatus. A wireless communication system. In a wireless communication system,
A plurality of radio base station devices;
A radio base station control device that controls each of the radio base station devices,
Among the plurality of radio base station devices, any one is a master radio base station device,
Among the plurality of radio base station devices other than the master radio base station, any one is a slave radio base station device,
The master radio base station apparatus and the slave radio base station apparatus are connected to the radio base station control apparatus, and the radio base station apparatus under control other than the master radio base station apparatus and the slave radio base station apparatus A wireless communication system characterized by being connected in a 1-to-n relationship (where n is an integer equal to or greater than 1). When the master radio base station apparatus cannot communicate with the radio base station control apparatus and the subordinate radio base station apparatus, a system switch packet is transmitted to the master radio base station apparatus,
The slave radio base station apparatus, based on the system switching packet, without losing a packet to be transmitted from the master radio base station apparatus, the subordinate radio base station apparatus or the radio base station control apparatus The wireless communication system according to claim 2, wherein the packet is transmitted.   The master radio base station apparatus adds the time stamp information or FCS information of a packet transmitted / received last before the communication becomes impossible to the system switch packet, and transmits the system switch packet. 3. The wireless communication system according to 3. In a system switching method in a radio communication system having a plurality of radio base station apparatuses and a radio base station control apparatus that controls the radio base station apparatus,
The master radio base station apparatus that is one of the plurality of radio base station apparatuses is connected to the connected radio base station apparatus in a 1-to-n relationship (n is an integer of 1 or more). When communication with the subordinate radio base station is not possible, a system switching packet is generated,
The master radio base station apparatus transmits the system switch packet to a slave radio base station apparatus that is one of the plurality of radio base stations other than the master radio base station apparatus,
The slave radio base station is connected to the connected radio base station controller and the subordinate connected in a 1: n basis without losing a packet to be transmitted from the master radio base station based on a system switching packet. Transmitting the packet to the wireless base station device of
A system switching method characterized by that.

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