JP2010011203A - Wireless relay system, repeater, and base station - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a wireless relay system, wherein centralized control is performed on connection management at a base station and a repeater is utilized to perform distributed control upon radio resource management. <P>SOLUTION: A wireless relay system includes a base station 1 which achieves the connection management under centralized control, and a repeater 2 which relays communication between the base station 1 and a terminal device 3. In the wireless relay system, the base station 1 performs radio resource management with the relay station 2. The repeater 2 comprises a virtual connection management unit 21 for acquiring from the base station 1 information on a connection established between the base station 1 and the terminal device 3 and controlling data transmission with the mobile station 3 on the basis of the obtained connection information, and under control of the virtual connection management unit 21, data transmission is performed using the connection between the repeater 2 and the terminal device 3. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a wireless relay system including a relay device.

  Conventionally, in a wireless communication system, information is transmitted on radio waves between a base station device (BS: Base Station) and a terminal device (MS: Mobile Station) and transmitted. However, since radio waves are attenuated by the influence of long communication distances and shielding objects, there is a dead zone where radio waves do not reach. For this reason, conventionally, a dead zone is eliminated by placing a relay device (RS) between the base station device and the terminal device and relaying radio waves by the relay device. Hereinafter, the wireless communication system including the relay device is referred to as a wireless relay system.

  In addition, the IEEE802.16 system (Non-patent Document 1 below), which has started service as WiMAX, also has a problem of dead zones. Standardization is in progress. In the MR system, two modes are defined: a method of performing centralized control by a base station device and a method of performing distributed control by a plurality of devices including a relay device. A specific method for performing dispersion control is disclosed in Patent Document 1 below.

  For example, when the connection management is centrally controlled by the base station device (Normal CID Allocation (IEEE802.16j)), the association with the service on the network side is easy, and the design of the connection management method is also easy. In addition, when radio resource management is distributedly controlled (distributed scheduling (IEEE802.16j)) between the base station apparatus and the relay apparatus, it is possible to perform efficient radio resource management in real time according to the radio wave propagation characteristics of each radio link. it can.

IEEE Std 802.16e-2005 Amendment2: Physical and Medium Access Control Layers for Combined Fixed and Mobile Operation in Licensed Bands 2005 IEEE P802.16j / D3 Multihop Relay Specification 2008 JP 2008-048422 A

  However, according to the above-described conventional technique, when connection management is performed by centralized control, the base station apparatus performs connection management for the relay apparatus and the terminal apparatus, and the relay apparatus performs connection management between the base station apparatus and the terminal apparatus. Not involved. Therefore, for example, when radio resource management is performed by distributed control, the relay device does not have information necessary to maintain QoS (Quality of Service) specified for each connection, and data with a connection as a basic unit. There was a problem that transmission and radio resource management could not be implemented.

  The present invention has been made in view of the above, and an object of the present invention is to provide a radio relay system that performs centralized control of connection management in a base station apparatus and performs distributed control of radio resource management using a relay apparatus. To do.

  In order to solve the above-described problems and achieve the object, the present invention includes a base station device that realizes connection management by centralized control, and a relay device that relays communication between the base station device and the terminal device, A radio relay system in which a base station device performs radio resource management with a relay device, and the relay device acquires information on a connection established between the base station device and a terminal device from the base station device. A virtual connection management unit that controls data transmission with the terminal device based on the connection information, and performs data transmission using the connection between the relay device and the terminal device under the control of the virtual connection management unit It is characterized by that.

  According to the present invention, even when the base station apparatus performs centralized control of connection management, the relay apparatus performs data transmission with the terminal apparatus without establishing a connection with the terminal apparatus. There is an effect that it is possible.

  Embodiments of a wireless relay system according to the present invention will be described below in detail with reference to the drawings. Note that the present invention is not limited to the embodiments.

Embodiment 1 FIG.
FIG. 1 is a diagram illustrating a configuration example of a first embodiment of a wireless relay system. The radio relay system includes a base station device (BS) 1, a relay device (RS) 2, a terminal device (MS) 3, a relay device connection 4, and a terminal device connection 5. The base station apparatus 1 performs connection management with the relay apparatus 2, connection management with the terminal apparatus 3, and radio resource management with the relay apparatus 2. The relay device 2 shares the terminal device connection 5 to perform data transmission, and performs radio resource management with the terminal device 3 based on connection information between the base station device 1 and the terminal device 3. . The terminal device 3 communicates with the relay device 2. The relay device connection 4 is a communication path that virtually connects the devices, and represents a connection (connection) established between the base station device 1 and the relay device 2. Similarly, the terminal device connection 5 is a communication path that virtually connects the devices, and represents a connection established between the base station device 1 and the terminal device 3.

  Further, the base station apparatus 1 includes a connection management unit 11 and a radio resource management unit 12. The connection management unit 11 centrally manages connections, and establishes a relay device connection 4 between the base station device 1 and the relay device 2, and establishes a terminal device connection 5 between the base station device 1 and the terminal device 3. The radio resource management unit 12 acquires connection information from the connection management unit 11 and performs radio resource management between the base station device 1 and the relay device 2.

  Further, the relay device 2 includes a virtual connection management unit 21 and a radio resource management unit 22. The virtual connection management unit 21 shares information about the terminal device connection 5 with the base station device 1 and holds the information. When transmitting data to the terminal device 3, the terminal device connection 5 is used. That is, the relay device 2 can perform the same processing as when a connection (connection) is established between the own device and the terminal device 3. The radio resource management unit 22 acquires connection information from the virtual connection management unit 21 and performs radio resource management between the relay device 2 and the terminal device 3. In addition, about the method by which the virtual connection management part 21 acquires connection information, you may acquire by the notification from the base station apparatus 1, or it acquires from the connection establishment message between the base station apparatus 1 and the terminal device 3. Also good.

  Next, the detailed configuration of each device will be described. FIG. 2 is a diagram illustrating a configuration example of the base station apparatus 1. In addition to the connection management unit 11 and the radio resource management unit 12, the base station device 1 includes a network side interface unit 13, a radio side interface unit 14, a packet processing unit 151, a PDU construction unit 152, and an encoding unit. 153, a modulation unit 154, a signal processing unit 155, a signal processing unit 161, a demodulation unit 162, a decoding unit 163, a PDU processing unit 164, and a packet construction unit 165.

  The network side interface unit 13 is an interface with a network. The wireless side interface unit 14 is a wireless interface with other devices. The packet processing unit 151 classifies and discriminates packets based on the connection information, and processes IP packets. The PDU construction unit 152 constructs a MAC PDU by adding a MAC header or the like. The encoding unit 153 encodes a packet to be transmitted. The modulation unit 154 modulates a packet to be transmitted. The signal processing unit 155 performs processing for conversion into an RF (Radio Frequency) signal. The signal processing unit 161 performs processing for converting the frequency of the received RF signal. The demodulator 162 demodulates the modulated received packet. The decoding unit 163 decodes the encoded received packet. The PDU processing unit 164 performs MAC PDU reception processing such as extraction of various control information included in the header. The packet construction unit 165 constructs a packet using the connection information.

  FIG. 3 is a diagram illustrating a configuration example of the relay device 2. In addition to the virtual connection management unit 21 and the radio resource management unit 22, the relay apparatus 2 includes a radio side interface unit 24, a packet processing unit 251, a PDU construction unit 252, an encoding unit 253, a modulation unit 254, A signal processing unit 255, a signal processing unit 261, a demodulation unit 262, a decoding unit 263, a PDU processing unit 264, and a packet construction unit 265. The PDU processing unit 264 performs MAC PDU reception processing such as extraction of various control information included in the header. In addition, the radio resource management unit 22 is notified of error information and credit information of the received data. In addition, each structure of the radio | wireless side interface part 24, the packet processing part 251-the signal processing part 255, the signal processing part 261-the decoding part 263, and the packet construction part 265 is the same as each structure of the corresponding base station apparatus 1. Since it is a function, description thereof is omitted.

  FIG. 4 is a diagram illustrating a configuration example of the terminal device 3. The terminal device 3 includes a connection management unit 31, a network side interface unit 33, a radio side interface unit 34, a packet processing unit 351, a PDU construction unit 352, an encoding unit 353, a modulation unit 354, and a signal processing. Unit 355, signal processing unit 361, demodulation unit 362, decoding unit 363, PDU processing unit 364, and packet construction unit 365. In addition, each structure of the connection management part 31, the network side interface part 33, the radio | wireless side interface part 34, the packet processing part 351-the signal processing part 355, and the signal processing part 361-the packet construction part 365 is the corresponding base station apparatus 1. Since the functions are the same as those of each of the components, description thereof is omitted.

  Next, the operation of each device when relaying the relay device 2 and transmitting data from the base station device 1 to the terminal device 3 will be described.

  The base station apparatus 1 presupposes that the connection management unit 11 establishes the relay device connection 4 and the terminal device connection 5 and retains the connection information thereof. First, the network interface unit 13 transfers the input IP packet to the packet processing unit 151. The packet processing unit 151 performs packet classification and discrimination based on the connection information from the connection management unit 11, and processes IP packets. Next, the radio resource management unit 12 allocates radio resources based on the type of connection, QoS information, and radio environment information (CQI: Channel Quality Information), and sends the information to the connection management unit 11 and the PDU construction unit 152. Notice. The PDU construction unit 152 constructs a MAC PDU based on the various information obtained from the connection management unit 11 and the radio resource management unit 12. Thereafter, the encoding unit 153 performs encoding processing, the modulation unit 154 performs modulation processing, the signal processing unit 155 performs signal conversion, and the wireless-side interface unit 14 relays the generated signal via an antenna. Transmit to device 2.

  The relay device 2 receives the signal transmitted from the base station device 1 by the wireless interface unit 24 and then converts the frequency of the received RF signal by the signal processing unit 261. Thereafter, the demodulation unit 262 performs demodulation processing, and the decoding unit 263 performs decoding processing. In addition, the PDU processing unit 264 executes MAC PDU reception processing based on the connection information held by the virtual connection management unit 21. In addition, the radio resource management unit 22 is notified of error information and credit information of the received signal. The packet construction unit 265 constructs a packet using the connection information and transfers the packet to the packet processing unit 251. Thus, the data reception process from the base station apparatus 1 is completed.

  Next, the relay device 2 performs a process of transferring data to the terminal device 3. First, the packet processing unit 251 performs packet classification and discrimination based on connection information from the virtual connection management unit 21, and processes IP packets. The virtual connection management unit 21 notifies the radio resource management unit 22 of connection information, QoS information, and radio environment information between the base station device 1 and the terminal device 3 obtained by the above acquisition method. The radio resource management unit 22 allocates radio resources based on the connection information, QoS information, radio environment information, and information obtained from the PDU processing unit 264, and the information is transmitted to the virtual connection management unit 21 and the PDU construction unit 252. Notify The PDU construction unit 252 constructs a MAC PDU based on the various information obtained from the virtual connection management unit 21 and the radio resource management unit 22. Thereafter, the encoding unit 253 executes the encoding process, the modulation unit 254 executes the modulation process, the signal processing unit 255 performs signal conversion, and the radio side interface unit 24 transmits the generated signal to the terminal via the antenna. Transmit to the device 3. At this time, the relay device 2 performs transmission using the terminal device connection 5 established between the base station device 1 and the terminal device 3.

  In the present embodiment, a case has been described in which relay device 2 constructs and transfers a packet from received data, but is not limited to the above processing. For example, the relay device 2 can perform PDU processing and transfer it. It is also possible to perform processing up to decoding in the relay device 2 and transfer after re-encoding. Further, any wireless relay system that centrally controls connection management and performs distributed control of wireless resource management can be applied to other wireless relay systems defined by IEEE 802.16j.

  Next, after the terminal device 3 receives the signal transferred by the relay device 2 by the wireless interface unit 34, the signal processing unit 361 converts the frequency of the received RF signal. Thereafter, the demodulation unit 362 performs demodulation processing, and the decoding unit 363 performs decoding processing. The PDU processing unit 364 performs MAC PDU reception processing based on the connection information held by the connection management unit 31. The packet construction unit 365 constructs a packet using the connection information and transfers it to the network side interface unit 32. The network side interface unit 32 transfers data to the network or application. As described above, the transfer process in the case of transmitting data from the base station apparatus 1 to the terminal apparatus 3 through the relay apparatus 2 is completed.

  As described above, when performing radio resource management by distributed control, the relay device 2 needs information on a connection established between the base station device 1 and the terminal device 3. Therefore, in the present embodiment, even when the base station apparatus 1 performs connection management by centralized control, the relay apparatus 2 shares information with the terminal apparatus connection 5 so as to communicate with the terminal apparatus 3. It was decided to establish a virtual connection. Thereby, the radio resource management by the relay apparatus 2 becomes possible.

  In the case of transmitting data from the base station apparatus 1 to the terminal apparatus 3, the operation of the base station apparatus 1 receiving data is not described, but the operation of the base station apparatus 1 receiving data is not described above. The operation is the same as the operation in which the terminal device 3 receives data. In addition, although the operation in which the terminal device 3 transmits data is not described, the operation in which the terminal device 3 transmits data is the same as the operation in which the base station device 1 transmits data.

  As described above, in the present embodiment, the relay apparatus shares the connection between the base station apparatus and the terminal apparatus and the connection information with the base station apparatus. Accordingly, even when the base station apparatus performs centralized control of connection management, the relay apparatus can perform data transmission with the terminal apparatus without establishing a connection with the terminal apparatus. . In addition, the wireless resource management can be distributed and controlled using the relay device.

  As an example of the wireless relay system, the MR system in IEEE 802.16j is used, but the present invention can also be applied to other wireless relay systems.

  Further, the configurations of the base station device, the relay device, and the terminal device have been described. However, the present invention is not limited to this configuration, and the present invention can also be applied to a multi-hop relay system or a multi-user relay system that passes through a plurality of relay devices.

Embodiment 2. FIG.
In the first embodiment, the connection between the base station device and the terminal device and the connection information are used for data transmission between the relay device and the terminal device. However, if the same QoS information is given to the base station apparatus and the relay apparatus, for example, the maximum delay amount may not be guaranteed. Specifically, the radio resource management unit of the base station apparatus is allocated radio resources so as to guarantee the QoS instructed by the host apparatus, and the radio resource management unit of the relay apparatus also guarantees the same QoS. Since radio resources are allocated, QoS is not guaranteed between the base station device and the terminal device even if QoS is guaranteed in each link (section in which each device communicates) (the maximum delay amount is doubled). there is a possibility. In the present embodiment, a wireless relay system that guarantees QoS as the entire system will be described.

  FIG. 5 is a diagram illustrating a configuration example of the second embodiment of the wireless relay system according to the present invention. The radio relay system according to the present embodiment includes a base station device 1a, a relay device 2a, a terminal device 3, a relay device connection 4, a terminal device connection 5, and a host device 6.

  The base station device 1a is different from the first embodiment in that the connection management unit 11a further includes a scheduling information generation unit 111. The scheduling information generation unit 111 acquires QoS information and ratio information necessary for generating scheduling information from the host device 6 and generates scheduling information based on the QoS information and ratio information. Here, the scheduling information is a value obtained by multiplying the value of each item defined by the QoS information by the ratio distributed to each device. Since other configurations and functions are the same as those in the first embodiment, description thereof is omitted.

  The relay device 2a is different from the first embodiment in that the virtual connection management unit 21a further includes a scheduling information generation unit 211. The scheduling information generation unit 211 acquires QoS information and ratio information necessary for generating scheduling information from the base station apparatus 1a, and generates scheduling information based on the QoS information and ratio information. Since other configurations and functions are the same as those in the first embodiment, description thereof is omitted.

  The host device 6 is a communication device corresponding to the host device of the base station device 1a, and manages QoS information in this wireless relay system. Further, ratio information necessary for generating scheduling information is determined based on information such as radio quality notified from each device.

Next, a specific operation of the scheduling information generation unit will be described. For example, a case is assumed where the maximum delay amount D, which is one piece of QoS information, is distributed at a ratio of a to b in the base station device 1a and the relay device 2a. Based on the QoS information (maximum delay amount D) and ratio information (a vs. b) notified from the host device, the scheduling information generation unit 111 of the base station device 1a determines the scheduling information (“delay amount D1” and the own device). To)
“D1 = (D × a / (a + b))”
Calculate and determine as Similarly, the scheduling information generation unit 211 of the relay device 2a uses the scheduling information (denoted as “delay amount D2”).
“D2 = (D × b / (a + b))”
Calculate and determine as In this way, each device determines the delay amount (scheduling information) based on the distributed ratio, so that the maximum delay amount from the base station device 1a to the terminal device 3 is set to “D1 + D2 = D”. It becomes possible.

  Here, a to b, which is the delay ratio information between the base station apparatus 1a and the relay apparatus 2a, varies depending on parameters such as the link radio propagation distance, radio environment state, radio quality, and system traffic distribution ratio in each apparatus. Value. In addition, the QoS information is not limited to the maximum delay amount D. For QoS information added for each link such as an average delay amount and delay jitter, a and b are determined for each link as described above. This makes it possible to guarantee QoS for the entire system. On the other hand, for QoS information that is not added for each link, for example, minimum throughput, maximum burst size, etc., it is not necessary to determine a ratio for distribution in each device, and QoS information is used as scheduling information as it is.

  The host device 6 notifies the base station device 1a of the QoS information and the ratio information necessary for generating the scheduling information. Further, the base station device 1a transfers the QoS information and the ratio information at the time of scheduling information generation to the relay device 2a. In the present embodiment, the base station device 1a may determine the ratio information between the own device and the relay device 2a. In this case, ratio information is determined based on the parameters obtained from the host device 6 and notified to the relay device 2a. Further, each of the base station device 1a and the relay device 2a may determine the ratio information of the own device based on the parameters obtained from the upper device 6.

  As described above, in this embodiment, scheduling information in each device is generated based on QoS information and the ratio information, and each device allocates radio resources based on the scheduling information and connection information. Thereby, QoS can be guaranteed for the entire wireless relay system.

  In addition, although this Embodiment demonstrated the case where each of a base station apparatus and a relay apparatus was provided with the scheduling information generation part, the base station apparatus produces | generates the scheduling information of an own apparatus and a relay apparatus, and the scheduling information of a relay apparatus May be notified to the relay device. Moreover, it is good also as producing | generating scheduling information in a high-order apparatus and notifying to a base station apparatus.

  As described above, the wireless relay system according to the present invention is useful for a wireless relay system including a relay device that relays communication between a base station device and a terminal device. In particular, in the system, connection management and Suitable for radio resource management.

1 is a diagram illustrating a configuration example of a wireless relay system according to a first embodiment. It is a figure which shows the structural example of a base station apparatus. It is a figure which shows the structural example of a relay apparatus. It is a figure which shows the structural example of a terminal device. 6 is a diagram illustrating a configuration example of a wireless relay system according to a second embodiment. FIG.

Explanation of symbols

1, 1a Base station device 2, 2a Relay device 3 Terminal device 4 Relay device connection 5 Terminal device connection 6 Host device 11, 11a, 31 Connection management unit 12, 22 Radio resource management unit 13, 33 Network side interface unit 14 , 24, 34 Radio side interface unit 21, 21a Virtual connection management unit 111, 211 Scheduling information generation unit 151, 251, 351 Packet processing unit 152, 252, 352 PDU construction unit 153, 253, 353 Encoding unit 154, 254 354 Modulation unit 155, 255, 355 Signal processing unit 161, 261, 361 Signal processing unit 162, 262, 362 Demodulation unit 163, 263, 363 Decoding unit 164, 264, 364 PDU processing unit 165, 265, 365 Packet construction unit

Claims (7)

A base station device that realizes connection management by centralized control and a relay device that relays communication between the base station device and a terminal device, and the base station device performs radio resource management with the relay device A wireless relay system,
The relay device is
A virtual connection management unit that acquires information on a connection established between the base station apparatus and the terminal apparatus from the base station apparatus, and controls data transmission with the terminal apparatus based on the connection information ,
With
A wireless relay system that performs data transmission using the connection between the relay device and the terminal device under the control of the virtual connection management unit. The relay device is
A radio resource management unit that performs radio resource management with the terminal device based on the connection information;
Further comprising
The radio relay system according to claim 1, wherein distributed control of radio resource management is performed by the base station apparatus and the relay apparatus.   The radio resource management unit of the base station apparatus and the relay apparatus performs the radio resource management so as to guarantee a predetermined QoS between the base station apparatus and the terminal apparatus. The wireless relay system according to 2. A relay device that relays communication between a base station device that realizes connection management by centralized control and a terminal device,
A virtual connection management unit that acquires information on a connection established between the base station apparatus and the terminal apparatus from the base station apparatus and controls data transmission with the terminal apparatus based on the connection information ,
With
A relay device that performs data transmission using the connection with the terminal device under the control of the virtual connection management unit. A radio resource management unit that performs radio resource management with the terminal device based on the connection information;
The relay apparatus according to claim 4, further comprising:   The relay apparatus according to claim 5, wherein the radio resource management unit performs the radio resource management so as to guarantee a predetermined QoS between the base station apparatus and the terminal apparatus. A wireless relay system is configured together with the relay device according to claim 4 or 5 that relays communication between the own device and the terminal device, connection management is performed by centralized control, and wireless resource management with the relay device is performed. A base station device to perform,
A base station apparatus that performs the radio resource management so as to guarantee a predetermined QoS between the own apparatus and the terminal apparatus.

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