JP4800162B2 - Wireless communication apparatus and control method thereof - Google Patents

Description

  The present invention relates to a wireless communication apparatus and a control method thereof.

In recent years, resource allocation control techniques for communication between a radio access network (RAN) and an IP network have been developed in mobile communication systems. For example, a technique for performing allocation control and distribution control by associating a radio access channel used for communication between the RAN and the IP network with a transmission / reception port (see Patent Document 1) has been proposed. .
JP 2004-172897 A (paragraphs 0008-0011, FIG. 1)

  Although the proposed technique described above can reduce control load bias and delay when connecting different types of networks, it does not provide appropriate QoS control for individual sessions on the wireless network side. For example, assume that there are multiple PPP sessions within the same mobile terminal. In such a situation, for example, when the packet transfer priority of each PPP session is set as a QoS value based on the Diffserve technique, it functions on the wired side (IP network) but does not function properly on the wireless side. do not do. The securing of the radio band, which is the resource on the radio side of each PPP session, is not guaranteed based on the QoS value described above, and there is a sufficient situation in which no radio band is secured (that is, no radio channel is allocated). Can happen. Since the conventional QoS control was developed for the priority side, the current technology cannot cope with channel allocation / release control on the radio side. Therefore, in the prior art, the priority control by QoS between each PPP session and the allocation control of the radio band required in each PPP session are independently managed separately, so that on the wired side (IP network) The abundant resources (broadband) and the resources on the wireless side (narrowband), which are overwhelmingly smaller than this, cannot be properly associated or allocated. Therefore, conventionally, when there are a plurality of sessions in the same mobile terminal and radio resources are insufficient, accurate QoS control cannot be provided for each session in the same mobile terminal. .

  Accordingly, an object of the present invention is to provide a radio communication apparatus capable of performing radio resource allocation control in consideration of packet control based on priority (QoS value) between sessions in a multi-session and a control method thereof. .

In order to solve the above-described problems, the wireless communication device (base station, communication terminal, etc.) according to the first invention
(A storage unit (such as a memory) that stores the priority (QoS) defined for each PPP session at the start of the PPP session)
Radio resource allocation unit (circuit, etc.) that performs radio resource allocation control for a plurality of PPP sessions based on the priority order specified for each session (for example, the QoS value by Diffserver specified for each PPP session) When,
For example, when there is data to be transmitted through a session such as a PPP (Point to Point Protocol) in the own device (for example, when there is a packet being queuing), the allocation control based on the priority order is the certain When there is no radio resource available for the PPP session (that is, when all the priorities of other PPP sessions to which the available radio resource is allocated are higher than the priority of the PPP session) ) Forcibly releasing at least one radio resource (regardless of priority) from other PPP sessions to which radio resources have been assigned, and assigning the released radio resource to the PPP session (ie, Exception allocation control that is not temporarily based on priority is performed), and the radio resource allocation unit is controlled. A control unit for (circuit, CPU, Sofutowaa modules etc.), provided with,
The control unit is
When an open radio resource is allocated to the certain PPP session, a time corresponding to data to be transmitted through the certain PPP session (that is, a guarantee time) maintains the allocation of the radio resource (that is, Control the radio resource allocation unit so as not to be released),
It is characterized by that.

A wireless communication apparatus according to the second invention is
The data to be transmitted through the PPP session is data that must be transmitted within a certain period in order to maintain the PPP session (typically, to the LCP echo request signal received from the partner terminal). Packet with response signal data)
It is characterized by that.

  As described above, the solution of the present invention has been described as an apparatus. However, the present invention can be realized as a method, a program, and a storage medium storing the program, which are substantially equivalent thereto, and the scope of the present invention. It should be understood that these are also included.

For example, a method for controlling a wireless communication apparatus according to the third aspect of the present invention, which is realized as a method,
(Storing step for storing the priority (QoS) defined for each PPP session in the memory at the start of the PPP session)
A radio resource allocation step for performing allocation control of radio resources (time slots, channels, etc.) for a plurality of PPP sessions based on the priority order defined for each PPP session;
When data to be transmitted through a certain PPP session is in its own device (when there is a queuing packet), in the allocation control based on the priority, there are radio resources that can be used for the certain PPP session. If it does not exist (that is, if all of the priorities of other PPP sessions that are assigned available radio resources are higher than the priority of the PPP session), A control step for forcibly releasing at least one radio resource from a PPP session and allocating the released radio resource to the PPP session;
In the control step, when a radio resource released to the certain session is allocated, the radio resource is configured to maintain the allocation of the radio resource for a time corresponding to data to be transmitted through the certain session. The allocating unit is controlled .

  According to the present invention, packet control based on priority (QoS) between sessions during a multi-session with a wireless communication terminal can be performed. In addition, when there is a limit to the radio resources that can be used in multi-sessions, the minimum necessary bandwidth can be secured even for sessions with low priority, and session maintenance is performed stably.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a block diagram of a wireless communication apparatus according to an embodiment of the present invention. As shown in the figure, the wireless communication apparatus 100 includes a storage unit 110 that stores a priority order (QoS) defined for each PPP session at the start of the PPP session, and a priority order (QoS based on Diffserver) defined for each PPP session. Value), the radio resource allocation unit 120 that performs radio resource allocation control for a plurality of PPP sessions, and the data to be transmitted through a PPP session are in the own apparatus. In the allocation control based on the above, when there is no radio resource that can be used for the certain PPP session, at least one radio resource is forcibly released from another PPP session to which the radio resource is allocated, and the certain PPP Allocate free radio resources to the session (ie temporarily Priority performs exception assignment control that is not based on the order), and a control unit 130 for controlling the radio resource assignment unit. The wireless communication apparatus 100 further includes a wireless reception unit 140 that receives data using the assigned wireless resource, a wireless transmission unit 150 that transmits data using the wireless resource, and an antenna ANT.

  The radio resource allocating unit 120 performs allocation control of radio resources to each session based on the priority (QoS value) defined for each session stored in the storage unit 110. Specifically, when data (packets) to be transmitted to a session with a high priority are queued, radio resources are given to the session with a high priority, and a low priority is given in exchange for that. Release radio resources from sessions with priority. Under priority-based assignment control, if there are no radio resources to be assigned to a session with a lower priority, depending on the conditions (which will be described in detail later), a radio from a session with a higher priority may be forced. Free up resources and allocate to low priority sessions.

  FIG. 2 is a network configuration diagram showing an example of a session configuration between a radio communication system base station and a mobile terminal capable of opening a plurality of PPP sessions. As shown in the figure, the mobile terminal MS and the base station BS communicate wirelessly and can open three PPP sessions S1-S3. The three PPP sessions S1-S3 can be opened / closed separately, and can be communicated individually. When communication is started in each PPP session, radio resources between the mobile terminal MS and the base station BS are individually acquired and are responsible for communication of each PPP session. The base station is connected to the network NW, and there is a server (not shown) ahead of the network NW, a partner terminal (not shown) of the PPP session connected to this server, and the like.

  In general, in order to maintain a session, it is necessary to periodically transmit a certain signal between devices related to the session. For example, when the counterpart terminal is Windows or the like, the PPP session is disconnected due to timeout unless a response signal to the LCP echo request signal is transmitted as an alive signal. For example, if an LCP echo request signal is transmitted from the partner terminal every minute and does not respond to this, the LCP echo request signal is retransmitted several times at intervals of 10 seconds or the like, and if the terminal does not respond to this as well The PPP session is forcibly terminated from the counterpart terminal as if the terminal side did not perform the session termination process, or the session was terminated, or there was some abnormality. For the user, the ongoing session suddenly goes down due to some error, and the user is forced to perform a predetermined reconnection operation (clicking or selecting an icon or radio button). Furthermore, when the partner wireless communication device, not the device itself, has a wireless resource allocation control right, there is a possibility that the wireless resource released by the end of the session may be intercepted by another communication terminal (node). . Therefore, there is a great disadvantage for the user that the PPP session is terminated even if it is temporary. It should be noted that the transmission of an alive signal for maintaining a PPP session is also required for other systems such as Linux. As will be described in detail later, according to the present invention, it is possible to guarantee the maintenance of the PPP session and to prevent session disconnection.

  In such a device, when considering a system for setting a QoS value for a PPP session using a method such as DSCP Marking by Diffserver, it is natural that each of the three PPP sessions S1, S2, and S3 in FIG. It is possible to set a QoS value (priority order) in Setting the QoS value in this way is synonymous with setting the priority to be processed of packets passing through each PPP session. Therefore, in order to perform the processing based on the priority order of packets, in the wireless communication system as shown in FIG. The system that puts on is common.

  In the case of such a system, in the case of different mobile terminals, it is basically possible to cope with it by assigning radio resources according to the priority order. In the present invention, in the case of a multi-session in which a plurality of PPP sessions exist in one mobile terminal, a situation occurs in which a usable radio resource is limited. Provides a resource allocation algorithm.

FIG. 3 is a network configuration diagram in which priorities are set for each session in the configuration of FIG. As shown in the figure, the three PPP sessions S1-S3 have the priority of BE (best effort) type, AF-PHB (Assured Forwarding) type, and EF-PHB (Expedited Forwarding) / type based on QoS. Is set. The BE (best effort) type has the lowest priority, the AF-PHB type has the medium priority, and the EF-PHB type has the highest priority. Therefore, the packet passing priority is S3 (EF-PHB). Type)> S2 (AF-PHB type)> S1 (BE type)
It becomes.

  Also, if this wireless system is divided into three timeslots by TDMA (Time Division Multiple Access), each PPP session can start a stream up to three, Each time slot must select a different channel. Therefore, usable radio resources are limited.

  FIG. 4 is a diagram showing an example of radio resource allocation in the session configuration of FIG. When data that needs to be transmitted occurs in the BE-type PPP session S1, one radio resource is consumed (that is, a pair of radio resources at the top and bottom) to start a stream (uplink slot U1, downlink) Slot D1). When there is a lot of data to be transmitted, further streams are started, and a maximum of 3 streams are started (uplink slots U2, U3, downlink slots D2, D3). In this state, when data to be transmitted is generated in the AF-PHB type PPP session S2, the PPP session S2 and the PPP session S1 are multi-sessions, and thus radio resources must be shared. Therefore, since the uplink slot U1-U3 and the downlink slot D1-D3 are already used in the PPP session S1, a new stream cannot be started. Accordingly, one stream used in the PPP session S1 is disconnected to secure radio resources, and then a stream is newly started in the PPP session S2.

  FIG. 5 is a diagram showing an example of radio resource allocation in the session configuration of FIG. In the state shown in FIG. 4, when there is data to be transmitted in the PPP session S2, it is necessary to secure a band for transmitting the data. Accordingly, the uplink slot U2 and the downlink slot D2, which are streams used in the PPP session S1, are further disconnected (released), and the free radio resources are reassigned to the PPP session S2 and used.

  The operation up to this point is basically the same as that of the prior art. A high priority session preferentially uses radio resources, while a low priority session holds radio resources. Perform the action.

  FIG. 6 is a diagram showing an example of radio resource allocation in the session configuration of FIG. In the state of FIG. 5, when there is more data to be transmitted in the PPP session S2, the radio resources (uplink slot U3 and downlink slot D3) used in the session S1 are further released (disconnected), Free radio resources are allocated to the PPP session S2. At this time, the available radio resources in the PPP session S1 are 0, so that packets to be transmitted are accumulated, that is, queued. Therefore, it is necessary to acquire radio resources again from the base station or the mobile terminal. In particular, when a queued packet is essential for session maintenance, the session itself may be disconnected due to timeout as described above.

  FIG. 7 is a diagram showing an example of radio resource allocation in the session configuration of FIG. As shown in the figure, all the radio resources are switched from the PPP session S1 to the PPP session S2, which has a higher priority, and are occupied by the PPP session S2. The resources (uplink slot U3, downlink slot D3) are disconnected (released), and free radio resources are allocated to the PPP session S1. Normal QoS control does not perform such priority inversion (exception processing). However, in the case of a wireless system, packets cannot be transmitted or received unless the communication channel is opened. Radio resources are secured to transmit packets.

  The number of radio resources that can be used in the PPP session S2 once becomes two by the operation of FIG. 7, but if necessary, an operation of disconnecting the radio resource of the PPP session S1 may be performed again. At this time, if the PPP session S1 is opened and the wireless resource is immediately disconnected, there is a possibility that packet transmission / reception may be almost impossible, so that the wireless resource once secured is occupied for a certain period of time. A mechanism to guarantee this is needed. The guarantee time should be determined by what kind of packet is transmitted / received, what is the purpose of communication, what kind of system, etc., which will be described later in detail.

  8-10 is a diagram of an example of radio resource allocation in the session configuration of FIG. In the state of FIG. 7, when a request for opening a communication channel is further generated in PPP session S3 which is EF-PHB, it is necessary to secure radio resources. In order to secure this radio resource, the radio resources (uplink slot U3, downlink slot D3) used in the PPP session S1 having the lowest priority are disconnected (released).

  If more radio resources are required in the PPP session S3, the radio resources (uplink slot U2, downlink slot D2) of the PPP session S2 are disconnected. At this time, the guaranteed time is taken into account, and if this is satisfied, disconnection is performed as shown in FIG. 9, and if none of the radio resources used in the PPP session S2 satisfies the guaranteed time, the PPP session S3 As shown in FIG. 9, it is necessary to temporarily suspend reservation of the wireless resource in FIG. 9 and disconnect the wireless resource of the PPP session S2 as shown in FIG.

  If more radio resources are required in the PPP session S1, an attempt is made to disconnect the radio resources of the PPP session S2, and if it is less than the guaranteed time, the PPP session S3 It is also possible to disconnect radio resources.

  If there is no radio resource that can be used in a situation where it is necessary to secure radio resources in a multi-session in this way, the radio resource currently in use is disconnected based on the priority order based on QoS or the like. Or, if necessary, radio resources are secured by reversing the priority order. By these methods, it is possible to realize an operation capable of maintaining the minimum necessary communication even in a low priority session while observing the basic priority. By maintaining and securing the minimum necessary communication, it is possible to maintain the session itself and avoid unnecessary disconnection of the session.

  FIG. 12 is a flowchart showing processing of the control method of the wireless communication apparatus considering the guarantee time according to the embodiment of the present invention. As shown in the figure, in Step P11, a StreamOpenRequest (transmission packet generation or the like) is detected in order to open a stream. In response to this, it is determined by referring to the resource management table or the like whether there is a free radio resource (step P12). When there is a radio resource, the process proceeds to Step P13, where the radio resource is secured, StreamOpen is performed, and the process ends (Step P14).

When it is determined in step P12 that there is no free wireless resource, it is determined whether or not another session is using the wireless resource in the multi-session (step P15). If another session is not using the radio resource, it is determined that there is no available radio resource (step P16), the StreamOpenFailed process is performed, and the process ends (step P17). If it is determined in step P15 that another session is using the radio resource, the process proceeds to step P18 to determine whether there are two or more sessions in use. When there are two or more sessions in use, another session having the lowest QoS is acquired from the group of sessions in use (step P19). In Step P20, the QoS of the local stream that is the target of stream opening is compared with the QoS of another session using Equation 1.
Own QoS ≥ Other QoS (Formula 1)
When Expression 1 is not satisfied, the process proceeds to Step P24, and further determination is performed using Expression 2.
Other QoS session stream duration ≥ Stream guarantee time (Equation 2)
When Expression 2 is not satisfied, the process proceeds to Step P25, the session of other QoS selected this time is set to be out of selection, and then the process returns to Step P15.

  If either of formulas 1 and 2 in steps P20 and P24 is satisfied, the process proceeds to step P21, the target QoS session is closed (radio resources are also released), and the other QoS session is started. The released radio resource is secured for a new stream (step P22), the stream open process is performed using the secured radio resource (step P23), and the process ends. According to this algorithm, it is ensured that each session secures radio resources for the guaranteed time, and efficient allocation control can be performed.

  As described above, according to the present invention, a system capable of controlling a plurality of frequencies such as a radio communication system base station, and capable of communicating with a mobile terminal at those frequencies, and a radio communication system base station, etc. In a system in which a plurality of PPP sessions can be opened between a mobile terminal and a mobile terminal, QoS control in a radio band is performed using a priority order based on QoS or the like between a plurality of PPP sessions (multi-session) in the same mobile terminal. Can be realized.

  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 member, each means, each step, etc. can be rearranged so as not to be logically contradictory, and a plurality of means, steps, etc. can be combined or divided into one. Is possible.

1 is a block diagram of a wireless communication device according to an embodiment of the present invention. It is a network block diagram which shows the example of a session structure of the radio | wireless communications system base station and mobile terminal which can open a several PPP session. FIG. 3 is a network configuration diagram in which priorities are set for each session in the configuration of FIG. 2. FIG. 4 is a diagram illustrating an example of radio resource allocation in the session configuration of FIG. 3. FIG. 4 is a diagram illustrating an example of radio resource allocation in the session configuration of FIG. 3. FIG. 4 is a diagram illustrating an example of radio resource allocation in the session configuration of FIG. 3. FIG. 4 is a diagram illustrating an example of radio resource allocation in the session configuration of FIG. 3. FIG. 4 is a diagram illustrating an example of radio resource allocation in the session configuration of FIG. 3. FIG. 4 is a diagram illustrating an example of radio resource allocation in the session configuration of FIG. 3. FIG. 4 is a diagram illustrating an example of radio resource allocation in the session configuration of FIG. 3. FIG. 4 is a diagram illustrating an example of radio resource allocation in the session configuration of FIG. 3. It is a flowchart which shows the process of the control method of the radio | wireless communication apparatus in consideration of the guarantee time by the embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Wireless communication apparatus 110 Storage part 120 Radio | wireless resource allocation part 130 Control part 140 Radio | wireless receiving part 150 Radio | wireless transmission part ANT Antenna BS Base station MS Mobile terminal NW Network S1-S3 PPP session U1 Uplink slot U2 Uplink slot U3 Uplink slot D1 Downlink slot D2 Downlink slot D3 Downlink slot

Claims (3)

A radio resource allocation unit that performs radio resource allocation control for a plurality of sessions based on the priority order specified for each session;
When there is data to be transmitted through a certain session in the own device, in the assignment control based on the priority, if there is no available radio resource for the certain session, the radio resource is allocated. A control unit that controls the radio resource allocating unit to forcibly release at least one radio resource from another session and to allocate the radio resource released to the certain session;
Equipped with a,
When the control unit allocates a radio resource released to the certain session, the radio resource allocation is performed so as to maintain the radio resource allocation for a time corresponding to data to be transmitted through the certain session. Control the part,
A wireless communication apparatus. The wireless communication device according to claim 1 ,
The data to be transmitted through the certain session is data that must be transmitted within a certain period in order to maintain the session.
A wireless communication apparatus. A radio resource allocation step for performing radio resource allocation control for a plurality of sessions based on the priority order defined for each session;
When there is data to be transmitted through a certain session in the own device, in the assignment control based on the priority, if there is no available radio resource for the certain session, the radio resource is allocated. A control step for forcibly releasing at least one radio resource from another session and assigning the released radio resource to the certain session; and
In the control step, when a radio resource released to the certain session is allocated, the radio resource is configured to maintain the allocation of the radio resource for a time corresponding to data to be transmitted through the certain session. A method for controlling a wireless communication apparatus, comprising: controlling an assigning unit .

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