JP5289258B2 - Communication system and communication method - Google Patents

Description

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

  In recent years, broadband communication networks such as the Internet have been developed. As means for realizing this, a wired broadband system using a wired connection such as FTTH (Fiber To The Home) and ADSL (Asymmetric Digital Subscriber Line), and wireless communication represented by Bluetooth (registered trademark), ZigBee, WiMAX, etc. Wireless broadband systems through the Internet are being built and used.

  In such a broadband system, particularly a wireless broadband system, a technology that enables optimal communication for a user using a wireless terminal has been proposed.

  For example, in a base station of a wireless broadband system, when assigning a wireless channel to a wireless terminal, the type of data to be transmitted / received and the priority of the wireless terminal are used.

  However, the base station assigns the radio channel without considering the load state on the network side, which is higher than the base station. For this reason, when a radio channel is allocated using the above-described information, there is a case in which a radio resource between the base station and the radio terminal and a resource on the network side are biased and an optimal allocation may not be achieved.

  In order to solve this problem, a technique for setting radio resources by grasping radio resources and resources on the network side has been proposed (see, for example, Patent Document 1).

JP 2002-374321 A

  However, in Patent Document 1 described above, the base station only uses resources based on the status of radio resources and higher-order resources at the time of allocation. For this reason, radio resources are not allocated after grasping the situation after reassignment (adjustment) of resources in the upper network part.

  The present invention has been made in view of such problems, and an object of the present invention is to perform efficient resource allocation in consideration of resources of radio resources and upper network portions in a base station. It is to provide a communication system and a communication method capable of performing the above.

  In order to achieve the above object, the present invention provides a communication system having a base station that performs wireless communication with a wireless terminal, and a control device that is connected to a higher-level device on the one hand and the base station on the other hand, In response to a radio resource allocation request from a radio terminal, radio resource status grasping means for grasping a radio resource status, and resource information relating to resources that can be allocated between the control device and the higher-level device to the control device Information requesting means for requesting, resource information acquiring means for acquiring the resource information from the control device, allocation means for allocating radio resources to the radio terminal according to the grasped radio resource status and the resource information; The control device includes a receiving unit that receives a request for the resource information from the base station, the control device, A resource status grasping means for grasping a resource situation concerning a network with a host device, an adjusting means for adjusting a resource based on the grasped resource situation, and the resource information based on the adjusted resource situation to the base station Transmitting means for transmitting.

  In the communication system according to the present invention, the resource status means a resource status between the control device and the higher-level device for the wireless terminal connected to a plurality of base stations including the base station, The resource information means information related to the resource amount allocated to the radio terminal that has made the radio resource allocation request based on the resource status and the maximum resource amount between the base station and the higher-level device.

  Further, in the communication system according to the present invention, the adjustment unit in the control device makes the radio resource allocation request according to the resource status, the maximum resource amount, and the communication status of the connected wireless terminal. Adjust resources allocated to wireless terminals.

  In order to achieve the above object, the present invention is a communication method of a communication system having a base station that performs wireless communication with a wireless terminal, and a control device that is connected to a higher-level device on the one hand and the base station on the other hand. The base station grasps a radio resource status in response to a radio resource allocation request from a radio terminal, and resource information on resources that can be allocated to the control device between the control device and the higher-level device Requesting the resource information from the base station, grasping the resource status regarding the network between the control device and the host device, and grasping the resource status And adjusting the resource information based on the adjusted resource status to the base station A transmitting step of transmitting, the base station acquiring the resource information from the control device, a step of allocating radio resources to the radio terminal according to the grasped radio resource status and the resource information; It is characterized by having.

  It is possible to perform efficient resource allocation in consideration of radio resources and higher-level network portions in the base station.

1 is a schematic configuration diagram illustrating a communication system according to an embodiment of the present invention. It is the functional block diagram which showed the structure of the base station of the communication system which concerns on embodiment of this invention, and a switching center control apparatus. It is the figure which showed the table of the information between radio | wireless resources and the resource management information managed in the communication system which concerns on embodiment of this invention. It is the figure which showed operation | movement in the communication system which concerns on embodiment of this invention.

Next, an embodiment of the present invention will be described with reference to the drawings.
(1) Configuration of communication system
First, the configuration of the communication system according to the present embodiment will be described.
(1.1) Overall schematic configuration
FIG. 1 is a schematic configuration diagram of a communication system according to the present embodiment. As shown in FIG. 1, the communication system 10 includes a radio base station 100 (100A, 100B), an exchange control device 200, a radio terminal 300 (300A to 300E), a network 400, a host device 500, and the like.
(1.2) Configuration of communication system
FIG. 2 is a functional block diagram illustrating configurations of the radio base station 100 and the switching center control device 200 included in the communication system 10 according to the present embodiment.
(1.2.1) Configuration of Base Station As shown in FIG. 2, the radio base station 100 includes an antenna 101, a radio communication unit 102, a buffer unit 103, a storage unit 104, a radio resource determination unit 105, and a radio control unit 106. , And an upper communication unit 107.

  The wireless communication unit 102 transmits and receives data with the wireless terminal 300 using the antenna 101.

  The buffer unit 103 temporarily stores data in order to control the order of received data at the time of data reception. The buffer unit 103 temporarily stores the data until the data transmission is completed at the time of data transmission.

  The storage unit 104 stores radio resource management information as information necessary for the operation of the radio resource determination unit 105 and the radio control unit 106. The radio resource management information is information for managing radio resources that can be provided by the radio base station 100. In this information, for example, the time when the wireless terminal 300 is connected to the wireless base station 100 and actually transmits / receives data using the assigned wireless resource (resource time), communication type, and assignment There is a radio resource amount (for example, in the case of iBurst (registered trademark), the radio resource is the number of time slots divided by time and frequency). FIG. 3A is a diagram showing radio resource management information stored in the storage unit 104 for the radio terminals 300A and 300B currently connected to the radio base station 100A.

  The radio resource determination unit 105 determines radio resources to be allocated to the radio terminal 300. First, the radio resource determination unit 105 stores radio resource management information stored in the storage unit 104 when the radio base station 100 receives a radio resource request (for example, a connection request to the radio base station 100) from the radio terminal 300. From this, the radio resource amount that can be allocated to the radio terminal 300 is grasped. Then, a radio resource to be allocated is determined from the graspable radio resource amount that can be allocated and resource information (details will be described later) acquired from the switching center controller 200. Then, information regarding the determined radio resource is output to the radio control unit 106.

  The wireless control unit 106 performs control related to wireless communication with the wireless terminal 300. For example, the modulation scheme to be set is determined according to the wireless quality during wireless communication with the wireless terminal 300. Further, the radio resource determination unit 105 is made aware of the radio resource amount that can be allocated to the radio terminal 300 that has made the radio resource request, and the maximum radio data transmission / reception amount that can be allocated to the radio terminal 300 based on the radio resource amount. Are both transmitted to the switching center controller 200 when requesting resource information. Then, the radio resource output from the radio resource determination unit 105 is allocated to the radio terminal 300 to the radio terminal 300 that has made the radio resource request.

The upper communication unit 107 transmits / receives data to / from the exchange control device 200.
(1.2.2) Configuration of switching center controller 200
As shown in FIG. 2, the switching center control device 200 includes a lower-level communication unit 201, a resource status grasping unit 202, a resource information generation unit 203, a storage unit 204, and a higher-level communication unit 205.

  The lower-level communication unit 201 transmits and receives data to and from the radio base station 100 (for example, 100A and 100B in FIG. 1).

  The resource status grasping unit 202 includes a resource adjustment unit 220. When receiving the resource information request from the radio base station 100, the resource status grasping unit 202 grasps the resource status related to the communication status with the host device of each radio terminal 300 connected to the plurality of radio base stations 100. In grasping the resource status, resource management information stored in the storage unit 204 is used. Using this resource management information, the maximum data transmission / reception amount that can be transmitted / received from the switching center controller 200 to the host device, and the assignable wireless maximum data transmission / reception amount transmitted together with the resource information request from the radio base station 100 It is possible to allocate the same amount of resources as the maximum amount of wireless data transmission / reception that can be assigned to the wireless terminal 300 that has made a wireless resource request from the switching center control device 200 to communication with the host device. Figure out. Then, when the resource status grasping unit 202 can allocate the resource status, the resource status grasping unit 202 outputs the fact to the resource information generating unit 203. On the other hand, when the allocation is impossible, the resource adjustment unit 220 performs resource adjustment.

  The resource adjustment unit 220 is a resource between the switching center control device 200 and the higher-level device, that is, a resource for transmitting and receiving data to be transmitted and received by the wireless terminal 300 connected to each wireless base station 100. (Details will be described later). After the adjustment, the resource management information stored in the storage unit 204 is updated, and information related to the secured resource amount is output to the resource information generation unit 203 by the adjustment. Also, information related to resource reduction that is transmitted to the radio base station 100 to which the radio terminal 300 with reduced resources is connected by the adjustment is output to the resource information generation unit 203.

The resource information generation unit 203 generates resource information and resource reduction information according to the information output from the resource status determination unit 202 and outputs the resource information and resource reduction information to the lower-level communication unit 201.
The storage unit 204 stores resource management information, which is the status of resources on the communication path between the exchange control device 200 and the host device. As the stored information, for example, in the wireless terminal 300 connected to each radio base station 100 connected to the switching center control device 200, the wireless terminal 300 is connected between the switching center control device 200 and the host device. Time during which data is actually transmitted / received using resources in the communication path (resource time), time since connection to the radio base station 100, data communication type, and radio terminal 300 There is an amount of data transmitted and received using resources on a communication path between the host device and the host device, and an allocated resource amount. FIG. 3B is a diagram showing resource management information stored in the storage unit 204 for the radio terminals 300A, 300B, 300C, and 300D that are currently connected to the radio base stations 100A and 100B connected to the switching center controller 200. It is.

The higher-level communication unit 205 transmits and receives data to and from the higher-level device via the network 400.
(2) Resource adjustment by switching center controller 200 and radio resource allocation of radio base station 100
Next, resource adjustment in the switching center controller 200 and radio resource allocation in the radio base station 100 of the communication system 10 according to the present embodiment will be described with reference to FIG.

  In wireless base station 100A, wireless terminals 300A and 300B are currently connected, and wireless resource management information is stored in storage unit 104 as shown in FIG. At this time, it is assumed that the wireless terminal 300E requests connection to the wireless base station 100A. At this time, the radio resource determination unit 105 determines the radio resource amount allocated to the radio terminals 300A and 300B, the type of data communication that the radio terminal 300E wants to perform, and the radio resource amount (number of time slots) not currently used. Therefore, the amount of radio resources (number of time slots) that can be allocated to the radio terminal 300E is grasped as M (M is an integer equal to or greater than 1). Then, the radio resource determination unit 105 determines the maximum radio data transmission / reception amount N (N: an integer of 1 or more) that can be transmitted / received by the radio terminal 300E, based on the grasped radio resource amount (number of time slots) M, as an exchange control device 200 is also transmitted together with the resource information request.

  When the switching center controller 200 receives a resource information request from the radio base station 100A, the resource status grasping unit 202 grasps the resource status from the resource management information stored in the storage unit 204, and is further transmitted together. It is ascertained whether or not a resource having the same amount as the wireless maximum transmission / reception data amount related to the wireless terminal 300E can be allocated by data transmission / reception between the exchange control device 200 and the host device.

  At this time, the total resource amount is W (W: an integer greater than or equal to 0), and the remaining resource amount is X (X: an integer greater than or equal to 0) considering the resource amount allocated to each wireless terminal 300. , N <X, so that the resource amount N can be allocated to the wireless terminal 300E, the resource information generated by the resource information generating unit 203 determines that the wireless terminal 300E requests the connection. The radio base station 100A that has performed the notification is notified.

  On the other hand, if the remaining resource amount is Y (Y: integer greater than or equal to 0) and N> Y, the resource amount N cannot be allocated to the wireless terminal 300E in the current resource allocation state. In this case, the resource adjustment unit 220 adjusts resources for the wireless terminal 300 connected to each wireless base station 100 to transmit / receive data that is a transmission source and a reception destination to / from a higher-level device.

  In resource adjustment, the resource adjustment unit 220 uses resource management information stored in the storage unit 204. First, the actual resource usage status in the wireless terminal 300 currently connected to each base station 100 is confirmed. For example, as shown in FIG. 3B, the wireless terminal 300A is performing communication by VoIP and is connected to the wireless base station 100 for a time during which data is actually transmitted / received using resources. Referring to the time since then, the ratio (P / F) actually used is high. On the other hand, as shown in FIG. 3B, the wireless terminal 300D has a relatively large amount of resources allocated, but the actually used ratio (U / I) is other wireless. It is assumed that it was lower than the terminal 300. In this case, for example, the resource amount allocated to the wireless terminal 300D is reduced by Z that does not hinder communication in the wireless terminal 300D. Then, according to the sum of the remaining resource amount Y and the reduced resource amount Z for the wireless terminal 300E, the resource amount that can be allocated to the wireless terminal 300E is sent to the wireless base station 100A that has made a connection request to the wireless terminal 300E. Notice. At this time, when N <Y + Z, the resource amount N is notified as resource information, while when N> Y + Z, the resource amount Y + Z is notified as resource information. Then, in the radio base station 100A that has received the resource information, the radio resource determination unit 105 determines a radio resource to be allocated to the radio terminal 300E and notifies the radio control unit 106, and the radio control unit 106 The resources are used to perform wireless communication with the wireless terminal 300E, and the wireless resource management information stored in the storage unit 104 is updated.

On the other hand, information indicating that the resource amount of the wireless terminal 300D has been reduced by Z is notified to the wireless base station 100B to which the wireless terminal 300D is connected, using the resource reduction information generated by the resource information generation unit 203. As a result, the radio base station 100B that has received the resource reduction information reduces the radio resource amount according to the reduced resource amount Z, and updates the radio resource management information stored in the storage unit 104.
(3) Operation of communication system 10
Next, operations of the radio base station 100 and the switching center control device 200 in the communication system 10 according to the present embodiment will be described.

  FIG. 4 is a diagram illustrating operations in the radio base station 100 (100A, 100B), the switching center control device 200, and the radio terminal 300.

  In step S401, the radio terminal 300 makes a connection request to the radio base station 100A. In step S402, the radio base station 100A that has received the connection request grasps the radio maximum data transmission / reception amount based on the radio resource amount from the radio resource amount that can be allocated to the radio terminal 300 from the radio resource management information. In step S <b> 403, the radio base station 100 </ b> A transmits information regarding the resource information request and the maximum data transmission / reception amount based on the radio resource amount that can be allocated to the radio terminal 300 to the switching center controller 200. In step S404, the switching center controller 200 grasps the resource status from the resource management information.

  In step S405, the switching center control apparatus 200 allocates the same resource as the maximum amount of transmission / reception data related to the wireless terminal 300 from the grasped resource status by data transmission / reception between the switching center control apparatus 200 and the host apparatus. Determine if you can. If allocation is possible (corresponding to step S405 Yes), the process proceeds to step S406. On the other hand, if allocation is not possible (corresponding to step S405 No), the process proceeds to step S407. In step S406, the switching center control apparatus 200 allocates resources to the radio terminal 300. In step S407, the switching center control apparatus 200 adjusts resources. At this time, it is assumed that the resource amount of the other radio terminal 300 connected to the radio base station 100B is reduced. In step S408, the switching center control apparatus 200 notifies the radio base station 100B that the resource amount of the radio terminal 300 to be connected has been reduced. In step S409, the radio base station 100B reduces the radio resource amount of the radio terminal 300 in response to the notification from the exchange control device 200.

  In step S410, the switching center control apparatus 200 transmits resource information to the radio base station 100A. In step S411, the radio base station 100 determines radio resources to be allocated to the radio terminal 300. In step S412, the radio base station 100 allocates radio resources to the radio terminal 300 and performs radio communication. On the other hand, in step S413, the switching center control device 200 updates the resource management information.

  Although the present invention has been described based on the drawings and examples, it should be noted that those skilled in the art can easily make various modifications and corrections based on the present disclosure. Therefore, it should be noted that these variations and modifications are included in the scope of the present invention. For example, functions included in each component, each step, and the like can be rearranged so as not to be logically contradictory, and a plurality of means and steps can be combined into one or divided. is there.

DESCRIPTION OF SYMBOLS 10 ... Communication system 100 ... Wireless base station 101 ... Antenna 102 ... Wireless communication part 103 ... Buffer part 104 ... Memory | storage part 105 ... Radio | wireless resource determination part 106 ... Radio | wireless control part 107 ... High-order side communication part , 200... Switching station control device, 201... Lower communication unit, 202... Resource grasping unit, 203... Resource information generation unit, 204. , 400 ... Network, 500 ... Host device.

Claims (4)

In a communication system having a base station that performs wireless communication with a wireless terminal, and a control device that is connected to the higher-level device on the one hand and the base station on the other hand,
The base station
In response to a radio resource allocation request from a radio terminal, radio resource status grasping means for grasping a radio resource status;
Information requesting means for requesting resource information relating to resources that can be allocated between the control device and the host device to the control device;
Resource information acquisition means for acquiring the resource information from the control device;
Allocating means for allocating radio resources to the radio terminal according to the grasped radio resource status and the resource information,
The controller is
Receiving means for receiving a request for the resource information from the base station;
Resource status grasping means for grasping a resource status related to the network between the control device and the host device;
Adjusting means for adjusting the resource based on the grasped resource status;
Transmitting means for transmitting the resource information based on the adjusted resource status to the base station;
A communication system comprising: The resource status means a resource status between the control device and the host device for the wireless terminal connected to a plurality of base stations including the base station,
The resource information means information related to a resource amount to be allocated to a radio terminal that has made the radio resource allocation request based on the resource status and a maximum resource amount between the base station and the higher-level device. The communication system according to claim 1. The adjusting means in the control device is:
Adjusting the resource allocated to the radio terminal that has made the radio resource allocation request according to the resource status, the maximum resource amount, and the communication status of the connected wireless terminal;
The communication system according to claim 2. A communication method of a communication system having a base station that performs wireless communication with a wireless terminal, and a control device that is connected to a higher-level device on the other hand and the base station, on the other hand,
The base station
In response to a radio resource allocation request from a radio terminal, grasping a radio resource status;
Requesting the control device for resource information relating to resources that can be allocated between the control device and the host device;
The controller is
Receiving a request for the resource information from the base station;
A step of grasping a resource status relating to a network between the control device and the host device;
Adjusting the resource based on the grasped resource status;
Transmitting the resource information based on the adjusted resource status to the base station;
The base station
Obtaining the resource information from the control device;
Allocating radio resources to the radio terminal according to the grasped radio resource status and the resource information;
A communication method comprising:

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