JP6648496B2 - Base station device, relay device, control method - Google Patents

Description

  The present disclosure relates to a base station device, a relay device, and a control method.

  Patent Literature 1 discloses a technique for preventing a decrease in QoE (Quality of Experience). QoE refers to service quality perceived by a user for services such as IP telephone and video distribution. When a large number of users perform data communication at the same time when users are concentrated in a specific cell, a shortage of radio resources occurs, and the throughput per user and the user QoE decrease.

  On the other hand, in the technique of Patent Literature 1, inter-cell load distribution control for effectively utilizing wireless resources is performed. Specifically, using the current radio resource usage rate in the serving cell, and a radio resource usage rate predicted value when handed over to a neighbor cell, the base station apparatus, from a specific cell where radio resources are tight, The mobile station is handed over to a neighboring cell.

JP 2015-5872

  As described above, in Patent Literature 1, a handover destination cell is selected based on the usage rate of radio resources in a specific cell.

  However, no cell is selected according to the application used in the mobile station.

  The purpose of the exemplary embodiment is to provide a new cell selection mechanism depending on the application used in the terminal device.

  A wireless communication system according to a control method of an exemplary embodiment includes a base station device having a plurality of frequency bands, and a terminal device configured to communicate with the base station device. The control method is based on a requirement regarding communication quality required for an application used by the terminal device, and calculates a radio resource for satisfying the requirement in at least one of the plurality of frequency bands. Including. The control method includes, when the calculated wireless resource exceeds a first predetermined value, selecting a frequency band for the terminal device from the plurality of frequency bands.

  The base station device according to the exemplary embodiment includes a plurality of frequency bands. The base station device includes a transceiver configured to communicate with a terminal device using at least one of the plurality of frequency bands. The base station apparatus calculates a radio resource for satisfying the requirement in the at least one frequency band based on a communication quality requirement for an application used by the terminal apparatus, and calculates the calculated radio resource. Has a processor configured to select a frequency band for the terminal device from among the plurality of frequency bands when the frequency band exceeds a first predetermined value.

  The relay device of the exemplary embodiment is configured to relay communication between a base station device configured to communicate with a terminal device using at least one of a plurality of frequency bands and an upper network. You. The relay device has a processor that creates a requirement regarding communication quality required for an application used by the terminal device. The relay device has a transmitter configured to transmit the created requirement to the base station device. The requirement is that the base station device calculates a radio resource to satisfy the requirement, and when the calculated radio resource exceeds a first predetermined value, a frequency band for the terminal device, To select from the plurality of frequency bands.

  According to the exemplary embodiment, a new cell selection mechanism according to an application used by the terminal device can be provided.

1 illustrates a wireless communication system of a first exemplary embodiment. 2 shows a configuration included in the wireless communication system of the first exemplary embodiment. 2 illustrates the operation of the first exemplary embodiment. 5 shows an operation for selecting a reconnection destination frequency band and a control target terminal according to the first exemplary embodiment. 4 illustrates an example of a change in a radio resource usage rate according to the first exemplary embodiment. 4 illustrates an example of a change in a radio resource usage rate according to the first exemplary embodiment. 4 illustrates an example of a change in a radio resource usage rate according to the first exemplary embodiment. 4 illustrates an example of a change in a radio resource usage rate according to the first exemplary embodiment. 2 illustrates a wireless communication system of a second exemplary embodiment. 4 illustrates the operation of the second exemplary embodiment. 4 illustrates the operation of the second exemplary embodiment. 4 illustrates the operation of the third exemplary embodiment. 4 illustrates the operation of the fourth exemplary embodiment. 14 shows a base station device of a fifth exemplary embodiment. 17 shows a modification of the base station apparatus of the fifth exemplary embodiment. 14 shows a relay device according to a fifth exemplary embodiment. 6 shows a sixth exemplary embodiment.

  An exemplary embodiment will be described in detail with reference to the drawings. In each of the drawings, the same or corresponding elements have the same reference characters allotted, and repeated description will be omitted as necessary to clarify the description. The plurality of exemplary embodiments described below can be implemented independently or can be implemented in appropriate combinations.

  Further, in this specification and the drawings, a plurality of components having substantially the same function and configuration may be distinguished from each other by adding different alphabets after the same reference numeral.

<First exemplary embodiment>
In a first exemplary embodiment, the base station alone creates the quality requirements of the application for each user (or terminal). The base station estimates required radio resources required for satisfying quality requirements for each user. The base station totals required radio resources in each frequency band included in the base station. The base station implements frequency band reselection control based on the aggregation result. Further, based on the requested radio resource, the base station selects a terminal to be controlled and a frequency band to be reconnected.

  FIG. 1 shows a configuration of a wireless communication system according to a first exemplary embodiment.

  The present embodiment relates to an LTE (Long Term Evolution) or LTE-Advanced wireless communication system.

  The wireless communication system includes an upper network (NW) 1, small cell base stations 2, and terminals 3. The upper network (NW) 1 is composed of, for example, the Internet. The terminal 3 is configured to communicate with the small cell base station 2. The small cell base station 2 has a plurality of frequency bands.

  The example of FIG. 1 shows a configuration for simplifying the description.

  In FIG. 1, the small cell base station 2 includes two frequency bands RF1 and RF2.

  The terminal 3-1 or the terminal 3-2 is located in a cell formed by the base station for each frequency band. Four terminals 3-1 use RF1. Four terminals 3-2 use RF2.

  In the present embodiment, the carrier aggregation technology is not applied. One terminal uses only one frequency band.

  It is also assumed that all terminals 3-1A to 3-1D are browsing the Web. It is assumed that all the terminals 3-2A to 3-2D are watching moving images. Here, it is assumed that one terminal does not use a plurality of applications at the same time.

  In FIG. 1, the number of small cell base stations and terminals, the positions of the terminals, the number of frequency bands per small cell base station, and the applications used by each terminal are merely examples, and the present invention is not limited thereto.

  Also, the small cells may be overlaid on a vast macro cell (not shown) formed by the macro base station. It is assumed that the outside of the coverage area of the small cell is covered by the macro cell. Further, the frequencies used in the macro cell and the small cell may be different from each other or may be the same. In this embodiment, it is assumed that the frequencies used in the macro cell and the small cell are different.

  FIG. 2 shows a configuration included in the wireless communication system of the first exemplary embodiment. In addition, since the configuration of all terminals is substantially the same, only a single terminal 3 is shown in FIG.

  Details of the small cell base station 2 are shown below.

  The small cell base station 2 includes a first transmission / reception unit 201, a second transmission / reception unit 202, an application quality requirement creation unit 203, a tally unit 204, a first selection unit 205, and a second selection unit 206. You.

  The first transmission / reception unit 201 is configured to transmit a control signal or a data signal including a reference signal on a downlink (downlink). The reference signal (reference signal) is used, for example, for the terminal to measure the communication channel quality with the base station.

  Further, the first transmission / reception unit 201 is configured to receive a control signal or a data signal including an uplink (uplink) reference signal.

  Further, first transmitting / receiving section 201 is configured to select a terminal to which data is transmitted on the downlink. The first transmission / reception unit 201 may include a scheduler that allocates a frequency resource (PRB: Physical Resource Block) and an MCS (Modulation and Coding Schemes) to the selected terminal.

  The first transmission / reception unit 201 is configured to process signals transmitted / received to / from a plurality of transmission / reception antenna elements.

  The first transmission / reception unit 201 is configured to set a radio quality reporting condition in each cell for each terminal.

  The first transmission / reception unit 201 is configured to receive, from the second transmission / reception unit 202, data addressed to a terminal from the upper NW1. The first transmitting / receiving unit 201 is configured to accumulate received data in a buffer. The first transmission / reception unit 201 is configured to transmit the stored data to each terminal via a wireless line.

  The second transmission / reception unit 202 is configured to receive data addressed to the terminal from the upper NW 1 via a wired line. Further, the second transmission / reception unit 202 is configured to transmit data from the terminal to the upper NW 1 via a wired line.

  The application quality requirement creating unit 203 is configured to create, for each application, a requirement (hereinafter, referred to as an application quality requirement or simply a requirement) for satisfying required communication quality for maintaining QoE. This application quality requirement can be created for each user. The application may be, for example, a Web application or a moving image application.

  As the application quality requirement, for example, throughput is used. Specifically, a target value of throughput set for each QCI (QoS Class Identifier), which is an identification index of Quality of Service (QoS) indicating network service quality, is set as the application quality requirement. Different values are set for the QCI of the web that is the interactive traffic class and the QCI of the moving image that is the streaming traffic class. The target value of the throughput is created by the base station based on the QCI when the user starts using the application. The QCI may be stored in a storage area such as a memory inside the base station in advance. This QCI may be notified in advance from a node included in the higher-level network, for example.

  The aggregation unit 204 is configured to estimate the required resource amount for each user using the application quality requirements of each user. The aggregation unit 204 is configured to total the required resource amounts of the connected users for each frequency band.

  Here, the resource indicates a frequency resource (PRB). Note that the required resource amount corresponds to the number of PRBs required to satisfy the application quality requirement. The details of the method of estimating the required resource amount and the method of summing the required resource amount will be described later.

  The first selection unit 205 starts frequency band reselection control for reselecting a frequency band different from the frequency band in use when the total value of the requested resource amounts satisfies a predetermined condition, and It is configured to select a frequency band to which the target terminal is reconnected. For example, when the total value of the requested resource amounts exceeds a predetermined upper limit Rth (for example, an amount corresponding to 90% of the total number of PRBs), the first selecting unit 205 determines that the total value of the requested resource amounts is equal to or less than Rth. Is configured to select an appropriate frequency band from the above frequency bands.

  The second selection unit 206 starts frequency band reselection control for reselecting a frequency band different from the frequency band in use when the total value of the required resource amounts satisfies a predetermined condition. The control target terminal to be reselected is configured to be selected. For example, when the total value of the requested resource amount exceeds Rth, the second selecting unit 206 selects a terminal to be controlled based on the requested resource amount.

  Note that each of the above-described configurations provided in the base station may be configured by at least one processor. Further, at least one of the above configurations can be configured as an integrated circuit (IC). Further, at least one of the above configurations may be configured as a program that operates on at least one processor.

  Next, the terminal 3 has at least the transmission / reception unit 301.

  The transmission / reception unit 301 is configured to transmit a control signal or a data signal including an uplink (uplink) reference signal. Further, the transmitting / receiving section 301 is configured to receive a control signal and a data signal from a base station including a downlink (downlink) reference signal. The transmission / reception unit 301 is configured to measure the radio quality of the connected frequency band and the other surrounding frequency bands.

  Note that the terminal 3 may include an output unit (not shown) for displaying a Web or a moving image. The output unit may include, for example, a speaker or the like that outputs audio related to a moving image.

  The radio quality may be, for example, Reference Signal Received Power (RSRP), which is the reception power of the downlink reference signal. The radio quality may be, for example, RSRQ (Reference Signal Received Quality), which is the reception quality of the downlink reference signal. RSRQ is defined as the ratio of RSRP to the total received power (RSSI: Received Signal Strength Indicator) in the same frequency band as the frequency band for measuring RSRP. The RSSI includes the received power from the own cell and the received power from at least one surrounding other cell. Each terminal can measure RSRP and RSRQ for its own cell and other cells.

  In the following, the operation of the first exemplary embodiment is shown.

  FIG. 3 shows an operation related to frequency band reselection control in the small cell base station 2. The operation in FIG. 3 is performed for at least one frequency band provided in each small cell base station. The operation in FIG. 3 may be performed for all frequency bands included in the small base station. The operation in FIG. 3 may be performed only for a specific frequency band among a plurality of frequency bands provided in the small base station. The operation in FIG. 3 may be performed at a predetermined cycle. The operation in FIG. 3 may be performed based on a predetermined trigger.

  In S101, the application quality requirement creation unit 203 acquires the application quality requirements of each user.

  In the present embodiment, it is assumed that each user (operator) owns one terminal. A certain user (operator) is browsing the Web using the terminal 3-1. Another user (operator) is watching a moving image using the terminal 3-2. A target value of the throughput (unit: Mbps, etc.) of the Web application is created for the terminal 3-1. Further, a target value of the throughput of the moving image application is created for the terminal 3-2. Each application is identified by a QCI.

  In order to maintain the QoE, the moving image application continues to reproduce the moving image at a constant bit rate. In a Web application, a user (operator) is required to acquire data as soon as possible after operating a terminal. Therefore, a Web throughput target value is set to a value larger than that of a moving image.

In S102, the counting unit 204 calculates the required resource amount of each user. Here, the requested resource amount is represented as R _{req, i} (t), where i is the user ID and t is time.

The required resource amount is defined as the number of PRBs necessary to satisfy the target value of the throughput per scheduling cycle (1 msec). The required resource amount is estimated using equation (1).

T _{PRB, i} (t) [Mbps / PRB] represents the measured value of the throughput in the wireless section per PRB for user i. T _{PRB, i} (t) can be determined, for example, from the number of transmission bits per PRB scheduled for user i per scheduling cycle (1 msec). Note that T _{PRB, i} (t) may be an instantaneous value at time t. T _{PRB, i} (t) may be an average value during one cycle in which the flowchart operation of FIG. 3 is performed. T _{PRB, i} (t) may be a total value during one cycle in which the flowchart operation of FIG. 3 is performed. This is obtained from the total number of transmission bits per PRB during one cycle.

In S103, the counting unit 204 calculates the total value of the requested resource amount for each frequency band. Here, the total value is expressed as TotR _{req, c} (t), where c is a frequency band ID (or also called a cell ID) and t is time.

  For example, the requested resource amounts of all terminals 3-1 are summed up for RF1. Requested resource amounts of all terminals 3-2 are summed up for RF2.

The total value is calculated based on equation (2). Here, Nc (t) represents the number of users using the application in frequency band c. For example, RF1 is 4 and RF2 is 4.

In S104, the tallying unit 204 compares the total value TotR _{req, c} (t) of the requested resource amount with the threshold value Rth for each frequency band. If there is a frequency band whose total value exceeds Rth (YES in S104), the process of S105 is executed. If there is no frequency band whose sum exceeds Rth (NO in S104), this flowchart ends. In the example of FIG. 1, it is assumed that the total value exceeds Rth in RF1 in which Web users are concentrated.

  In S105, the reselection control of the frequency band is started for the frequency band whose sum exceeds Rth.

  FIG. 4 shows an operation of selecting a terminal to be controlled and a frequency band to which the terminal reconnects in the frequency band in which the reselection control has been started in S105 of FIG.

In S111, a surplus resource amount (hereinafter, referred to as R _{rem, c} (t)) is calculated in a frequency band other than the frequency band in which the reselection control has been started. The frequency band other than the frequency band for which the reselection control has been started is a frequency band in which it is determined in S104 that the total value of the requested resource amounts does not exceed Rth (NO in S104).

The surplus resource amount is defined as a surplus resource amount with respect to the upper limit Rth. The surplus resource amount can be expressed as Expression (3).

In S112, it is determined whether or not the surplus resource amount R _{rem, c} (t) is greater than 0 in at least one frequency band.

When there is no frequency band _satisfying R _{rem, c} (t)> 0 (in the case of “NO” in S112), the reconnection destination frequency band cannot be selected, and thus this flowchart ends.

If there is a frequency band _satisfying R _{rem, c} (t)> 0 (if “YES” in S112), the process of S113 is executed.

In S113, one frequency band having the maximum surplus resource amount R _{rem, c} (t) is selected. Here, a frequency band having a surplus resource amount equal to or larger than a predetermined threshold may be selected. The selected frequency band is the frequency band to which the terminal reconnects. There is a large deviation in the required resource amount between the frequency band that has started the frequency band reselection control and the frequency band to which the terminal reconnects. In the example of FIG. 1, RF2 is selected as the frequency band of the reconnection destination.

In S114, a difference Δi between the surplus resource amount in the frequency band selected in S113 and the required resource amount for each user i in the frequency band in which the reselection control has been started is calculated. Here, it is assumed that the required resource amount R _{req, i} (t) of each user after frequency band reselection is the same as before reselection. In the example of FIG. 3, RF1 and RF2 are frequency bands of the same base station, and the radio quality can be assumed to be substantially the same.

  In S115, it is determined whether Δi is 0 or more for at least one user.

  If Δi is negative for all the users (“NO” in S115), there is no user whose connection can be switched to the selected frequency band, and thus this flowchart ends.

  If there is a user whose Δi is 0 or more (“YES” in S115), S116 is executed.

  In S116, one user having the smallest Δi is selected. Since the selected user becomes a control target, it is possible to eliminate a large bias in the required resource amount between the frequency band in which the frequency band reselection control is started and the other frequency bands.

  In S117, the connection destination of the user selected in S116 is switched to the frequency band selected in S113. This switching corresponds to inter-frequency handover (HO) performed between cells having different frequencies. This HO is forcibly performed regardless of the radio quality required for the HO such as RSRP.

  In S118, the total value of the requested resource amount is updated in the frequency band in which the frequency band reselection control is activated and the frequency band selected as the reconnection destination in S113. At this stage, since the HO processing performed in S117 is not completed, it is calculated as a temporary total value.

  In S119, in the frequency band in which the frequency band reselection control has started, the total value of the requested resource amounts updated in S118 is compared again with Rth.

  If the updated total value is equal to or smaller than Rth (YES in S119), the flowchart ends. That is, the situation where QoE is degraded due to the requested resource amount exceeding the upper limit value Rth is improved.

  If the updated total value still exceeds Rth (NO in S119), the process of S120 is executed.

  In S120, the total number of users selected as the control target terminals is compared with the threshold number Nth of the number of users. By this comparison, it is determined whether a user other than the user selected in S116 can be additionally selected. This additional selection is performed when the required resource amount cannot be sufficiently reduced by only one user. Thus, an attempt is made to further reduce the required resource amount.

  Nth corresponds to the upper limit of the number of HO processes that can be performed simultaneously. If the total number of selected users exceeds Nth (YES in S120), HO cannot be performed at once, and thus this flowchart ends. If Nth or less (NO in S120), the operation of selecting a control target terminal is performed again from S116 except for the user already selected in S116.

  5A to 5D show an example of a change in the radio resource usage rate when the present embodiment is implemented.

  FIG. 5A shows wireless resource usage rates (instantaneous values) when Web users are concentrated on frequency band RF1 and moving image users are concentrated on frequency band RF2. Here, the radio resources in RF1 and the radio resources in RF2 are used up to the upper limit (100%).

  FIG. 5B shows an example of a required value (requested resource amount) of a radio resource usage rate necessary to satisfy a predetermined QoE in the same situation as in FIG. 5A. This request value corresponds to a value obtained by dividing the total value of the requested resource amounts by the number of available PRBs. It is assumed that a Web user has a higher required value than a moving image user.

  Compared to FIG. 5B, each Web user at RF1 in FIG. 5A has a radio resource actually used lower than the required value. If this communication is continued, the requested radio resource cannot be secured, and there is a high possibility that QoE will be degraded.

  In addition, since the radio resources actually used exceed the required value for all moving picture users in RF2, QoE does not deteriorate but the throughput temporarily becomes excessive.

  FIGS. 5C and 5D show examples in which the operation of the present embodiment is performed in the situations of FIGS. 5A and 5B. However, in FIG. 5D, the required value of the radio resource usage rate is set on the vertical axis for unification with FIG. 5C. This request value corresponds to a value obtained by dividing the total value of the requested resource amounts by the number of available PRBs.

  5C and FIG. 5D show the radio resource usage rate (FIG. 5C) after selecting one user from the RF1 Web users and causing RF2 to perform HO with respect to FIGS. 5A and 5B. This shows the required value of the usage rate (FIG. 5D). By making the HO the Web user from RF1 to RF2, the required value of RF1 can be reduced to the upper limit or less while the required value of the radio resource usage rate of RF2 is suppressed to the upper limit (100%) or less. As a result, the QoE of the Web user can be improved while maintaining the QoE of the video user.

  In this manner, even in a situation where the radio resources of both RF1 and RF2 are used up to the upper limit (FIG. 5A), the load can be distributed by switching the frequency band. Therefore, deterioration of QoE in RF1 can be prevented, and excessive throughput in RF2 can be avoided.

  As described above, according to the present embodiment, the inter-frequency HO is performed based on the radio resource amount requested by the application even in a situation where the actual radio resource usage rate is high. As a result, it is possible to correct the bias of the required resource amount between the frequency bands and improve the QoE that has been reduced due to the concentration of the applications.

  The procedures shown in FIGS. 3 and 4 can be realized by causing a computer of a processor (such as a microprocessor) to execute a program for controlling the base station. That is, the computer that executes the base station control program may cause the computer to execute the frequency band reselection control and perform the process of selecting the control target terminal and the reconnection destination frequency band.

  Note that, in the present embodiment, an example in which the target value of the throughput based on the QCI is used as the application quality requirement created independently by the base station has been described, but the present invention is not limited to this.

  The application quality requirement may be based on, for example, a function of DPI (Deep Packet Inspection) included in the small cell base station 2. The small cell base station 2 inspects a passing packet by performing DPI on the data addressed to the terminal 3 transferred from the upper NW 1 and identifies an application related to the passing packet. For example, a target value of the throughput is set for each identified application.

  Note that the application quality requirement is not limited to the throughput required for each application in order to maintain QoE. For example, the application quality requirement may be any of a delay time, a transmission data size required to be received at a predetermined time, or a time and a frequency of interruption of an application such as a moving image playback. For example, it may be required that the data transmission delay be equal to or less than a predetermined value.

  For example, in the case of a moving image application, when the moving image data does not reach the terminal sufficiently, a high download throughput may be required as the application quality requirement in order to prevent the reproduction from being interrupted. On the other hand, when the moving image data is sufficient in the terminal (when the buffer is sufficiently buffered), reproduction interruption is unlikely to occur, so that a requirement for low throughput may be set as the application quality requirement.

  Further, for example, in the case of a Web application, a requirement for a high throughput in order to acquire data immediately after a terminal is operated may be set as an application quality requirement.

  Thus, the application quality requirement can be set as a time-varying quality requirement.

  In the present embodiment, the frequency band having the largest surplus resource amount is selected as the frequency band of the reconnection destination, but is not limited to this. For example, if the surplus resource amount is equal to or more than a predetermined value, an arbitrary frequency band may be selected.

  The criterion for selecting a frequency band may be not only an absolute value but also a relative value. Instead of using the surplus resource amount, a frequency band in which the total value of the requested resource amount is smaller than the frequency band currently used by the control target user may be selected. For example, when there is a difference between the required resource amount in the selected frequency band and the required resource amount in the frequency band currently used by the control target user, the frequency band may be selected. When the relative value corresponding to this difference exceeds a predetermined value, the frequency band may be selected.

  In the present embodiment, a user who has the smallest difference between the surplus resource amount and the requested resource amount is selected as the control target user, but the present invention is not limited thereto. For example, if the requested resource amount is equal to or more than a predetermined value with the surplus resource amount as an upper limit, an arbitrary user may be selected.

  A user who has the largest difference between the requested resource amount and the actually used resource amount may be selected without using the surplus resource amount to prevent a decrease in QoE.

  In the present embodiment, the control target user is selected after the reconnection destination frequency band is selected, but the control order is not limited to this. For example, after the control target terminal is arbitrarily selected, a frequency band having a surplus resource amount equal to or more than the required resource amount of the selected terminal may be selected as the frequency band of the reconnection destination.

  In the present embodiment, the required resource amount is defined using the number of PRBs, but is not limited to this. For example, the required resource amount may be defined using a PRB usage rate obtained by dividing the number of PRBs by the number of PRBs available per frequency band.

  Note that, in the example of the present embodiment, after the frequency band is reselected, the required resource amount of each user is the same as before the reselection, but is not limited to this. For example, in FIG. 3, when the difference between the RSRP of RF1 and the RSRP of RF2 is equal to or larger than a predetermined value, it is assumed that the radio quality changes. In this case, the required resource amount may be corrected using both RSRPs, and the total value of the required resource amounts may be updated. This correction may be, for example, to correct the MCS by an amount corresponding to the difference in RSRP.

  In the present embodiment, the terminals 3-1 and 3-2 do not use a plurality of applications at the same time, but the present invention is not limited to this. For example, the terminal may use a plurality of applications simultaneously.

  In this case, the sum of the requested resource amounts may be for all applications of each user. The inter-frequency HO in the frequency band reselection control is performed for each terminal. In this case, when the user to be controlled uses a plurality of applications, all the requested resources corresponding to those applications may be set as the HO targets.

  Further, the total of the requested resource amounts may be targeted for each application. In this case, the inter-frequency HO in the frequency band reselection control is performed for each application. For example, when a plurality of applications are used in a certain terminal, a required lease amount may be calculated for each application, and HO may be executed for each application based on the calculated required resource amount. The HO for each application means that a certain application is shifted from the first frequency band to the second frequency band. After this transition, for example, the first frequency band can be used for application A and the second frequency band can be used for application B.

<Second exemplary embodiment>
In the present embodiment, the application quality requirement is created by an external relay device other than the base station. Specifically, a relay device 4 that relays data between the NW 1 and the small cell base station 2 is further provided, and the relay device 4 creates an application quality requirement.

  FIG. 6 shows a wireless communication system of the second exemplary embodiment.

  In FIG. 6, the wireless communication system includes an upper network 1, small cell base stations 2, terminals 3, and relay devices 4.

  FIG. 6 is different from FIG. 2 in that the small cell base station 2 does not include the application quality requirement creation unit 203 but the relay device 4 includes an application quality requirement creation unit 401.

  Other configurations in FIG. 6 are the same as those in FIG. 2, and thus description of the other configurations is omitted.

  The relay device 4 includes an application quality requirement creating unit 401. The application quality requirement creation unit 401 creates a requirement (also referred to as an application quality requirement or simply a requirement) for satisfying communication quality required by an application such as a Web or a moving image used in the terminal 3. In the present embodiment, in order to facilitate the description, the throughput is used as the communication quality, and the required condition is indicated as the required throughput.

  The required throughput is obtained (estimated) by measuring the actual traffic flow in the TCP (Transmission Control Protocol) layer for each application, and is updated every moment.

  For example, in the case of Web traffic, the required throughput is set higher as the traffic flow (content size) of the information source (page to be viewed) is larger.

  Also, in the case of video traffic, it is estimated that the larger the traffic flow rate, the more data reaches the terminal. That is, when it is determined that more data has arrived, it is presumed that the reproduction of the moving image is not affected. In this case, the required throughput is set low.

  The protocol for which the required throughput is measured is not limited to TCP. For example, the measurement target may be a UDP (User Datagram Protocol) or another transport layer or application layer protocol.

  The following describes the operation of the present embodiment.

  FIG. 7 is a flowchart related to an operation of creating an application quality requirement in the relay device 4. Note that the operation in FIG. 7 may be performed by the relay device 4 at a predetermined cycle. The operation in FIG. 7 may be performed at an arbitrary timing based on a predetermined trigger.

  In S401, the application quality requirement creating unit 401 creates an application quality requirement for each application flow. The required throughput is created according to the traffic flow in the TCP layer and the application. Note that the application quality requirement may be created according to the terminal. That is, even in the case of the same type of application, different application quality requirements can be created for different terminals.

  In S402, the application quality requirement creating unit 401 notifies the small cell base station via a wired line of the application quality requirement created for each application flow.

  However, it is assumed that the relay device 4 has grasped the connection relationship (or IP address correspondence relationship) between each terminal 3 and the small cell base station 2. Also, the relay device 4 can specify a small cell base station to which the application quality requirement is notified. Further, the application quality requirement may be periodically notified as individual control information in layer 2. Further, the application quality requirement may be notified as needed as header information in a packet of user data.

  FIG. 8 is a flowchart illustrating frequency band reselection control in the small cell base station 2.

  FIG. 8 differs from FIG. 3 in that S101 is replaced with S501. Since the other operations in FIG. 8 are the same as those in FIG. 3, a description of the other operations will be omitted. After the frequency band reselection control is performed, the operation of selecting the control target terminal and the frequency band of the reconnection destination is the same as that in FIG.

  In S501, the small cell base station 2 acquires the application quality requirement created by the application quality requirement creation unit 401 in the relay device 4 via a line (wired line or wireless line). After the acquisition, the application quality requirement is transferred to the tallying unit 204 via the second transmitting / receiving unit 202.

  As described above, in the present embodiment, the application quality requirement is created based on the traffic flow of the TCP layer for each application flow. For this reason, frequency band reselection control is performed based on more accurate application quality requirements.

  Protocols defined by LTE and LTE Advanced correspond to protocols below layer 2 (data link layer) in the OSI (Open Systems Interconnection) basic reference model. Therefore, in a wireless communication system including LTE, a terminal and an application server communicate using a protocol of Layer 3 (network layer) or higher in the OSI basic reference model, such as TCP. On the other hand, the terminal and the base station communicate using a layer 2 or lower protocol. Therefore, the accuracy of the application quality requirement based on actual traffic demand may be low with only the base station. In consideration of this possibility, in the present embodiment, the relay device 4 relays communication using the protocol of the layer 3 or higher, so that a more accurate application quality requirement can be created. Can be used to perform frequency band selection.

<Third exemplary embodiment>
In the above exemplary embodiment, if the terminal is not connected to any frequency band, the base station selects a frequency band for the terminal based on the measurement report received from the terminal. Here, the measurement report includes reception quality (for example, RSRP, RSRQ, and the like) related to the frequency band measured by the terminal.

  In contrast, in the third exemplary embodiment, a frequency band is selected (initial selection) based on the total amount of required resources for existing terminals. Note that the configuration of the present embodiment is the same as that of the first embodiment, and a description thereof will not be repeated.

  FIG. 9 shows an operation of initial selection of a frequency band in a small cell base station.

  The operation in FIG. 9 is performed when the small cell base station receives a new band use request from a terminal (new terminal) that is not connected to the local cell base station.

  For example, the operation in FIG. 9 may be performed when the base station receives an RRC (Radio Resource Control) Connection Setup message transmitted when a terminal in a standby state (Idle mode) starts data communication. Alternatively, the operation in FIG. 9 may be performed when a terminal that is performing data communication has handed over from another base station to the small cell base station.

  In S601, the frequency band having the largest surplus resource amount is initially selected for the terminal that has newly transmitted the band use request, similarly to 113 in FIG. Note that a frequency band having a surplus resource amount equal to or larger than a predetermined threshold may be selected.

  However, the total value of the requested resource amounts in Expression (3) is calculated based only on the terminals using each frequency band.

  As described above, in the present embodiment, the frequency band is initially selected in advance so that the required resource amount is balanced between the frequency bands at the start of communication. For this reason, the probability that the total value of the requested resource amounts exceeds the upper limit value is reduced. Further, the frequency of occurrence of QoE degradation can be reduced.

<Fourth exemplary embodiment>
The present embodiment relates to carrier aggregation in which a plurality of frequency bands are bundled and used at the same time. In the carrier aggregation, the base station can use one frequency band or use a plurality of frequency bands bundled at the same time after matching which frequency band to use with the terminal. In the carrier aggregation, a cell in which a control RRC connection is first established is called a primary cell. A cell additionally provided with a data connection is called a secondary cell. The primary cell is a cell having the highest reception quality such as RSRP and RSRQ. A cell other than the primary cell whose reception quality is equal to or higher than a predetermined level is selected as a secondary cell.

  In Embodiments 1 to 3, all terminals do not apply carrier aggregation and perform forced HO between different frequency bands, thereby performing frequency band reselection.

  In the present embodiment, there is a terminal to which carrier aggregation is applied. Releasing the secondary cell for this terminal is referred to as frequency band reselection. That is, it is assumed that selecting “not using a secondary cell” is reselection.

  Note that the configuration of the present embodiment is the same as that of the first embodiment, and a description thereof will not be repeated.

  Conditions such as whether the terminal can execute carrier aggregation and which frequency band can be used depend on the physical configuration of the terminal. Therefore, in a certain frequency band, terminals to which carrier aggregation is applied and terminals to which carrier aggregation is not applied may coexist. For example, if a terminal that cannot perform carrier aggregation and can use only one frequency band is connected to the same frequency band many times, the required resource amount may be biased in that frequency band compared to other frequency bands .

  In the following, details regarding the operation in the present embodiment will be described.

  First, the operation of determining whether to perform frequency band reselection control in the small cell base station 2 is described below. The flowchart relating to the present embodiment is the same as FIG. However, the formula (2) for calculating the total value of the requested resource amounts in S103 is different.

In the present embodiment, the total value is calculated as in equation (4). Here, the difference from the equation (2) is that a coefficient α _{i, c} is introduced for each frequency band c of the user i. The coefficient α _{i, c} is defined as a sharing ratio of the required resource amount shared in each frequency band c. Its value is between 0 and 1. The sum for c is 1. For example, in the case of simple equal distribution, that is, when the number of component carriers is 2 (c = 1, 2), α _{i, c} is set to 0.5 regardless of c. Alternatively, when based on the reception quality such as the RSRP, the component carrier having a higher RSRP has a higher reception quality. Therefore, α _{i, c} may be set to a large value. Alternatively, based on the required resource amount, αi _{, c} may be set to a large value because a component carrier having a smaller total requested resource amount can use more resources.

  FIG. 10 shows an operation of selecting a terminal to be controlled in a frequency band in which reselection control has been started after the operation of FIG.

  In S911, it is determined whether there is a user satisfying the condition. A user who satisfies the condition is a user who uses two or more component carriers and uses a component carrier that has started frequency band reselection control as a secondary cell.

  If this user exists (YES in S911), the processing in and after S912 is executed to select a user to release the secondary cell.

  If this user does not exist (NO in S911), this flowchart ends.

  In S912, the user with the largest requested resource amount is selected. This user is the control target terminal.

  In S913, the use of this component carrier is stopped for the user selected in S912. For example, the component carrier may be released to stop. For example, the scheduler may prohibit radio resource allocation from the component carrier.

In S914, the coefficient α _{i, c} for the user selected in S912 is updated. Specifically, α _{i, c} for the present component carrier is set to 0, and the reduced amount is allocated to another component carrier.

  In S915, the total value of the requested resource amount is updated in the component carrier that has activated the frequency band reselection control. In S915, since the stop processing performed in S913 is not completed, it is calculated as a temporary total value.

  In S916, as in S119 of FIG. 4, in the present component carrier, the total value of the requested resource amounts updated in S915 is compared again with Rth. If the updated total value is equal to or smaller than Rth (YES in S916), the flowchart ends. As a result, it is possible to recover from the situation where the required resource amount exceeds the upper limit and QoE deteriorates.

  If the updated total value still exceeds Rth (NO in S916), the operation of S917 is executed.

  In S917, as in S120 of FIG. 4, the total number of users selected as the control target terminals is compared with the threshold number Nth of the number of users. By this comparison, it is determined whether a user other than the user selected in S912 can be additionally selected.

  If the total number of selected users exceeds Nth (YES in S917), this flowchart ends. Note that Nth corresponds to the upper limit of stop processing that can be performed simultaneously. If the total number of selected users exceeds Nth, the stop processing cannot be performed at once, and the flowchart ends.

  If Nth or less (NO in S917), the operation of selecting the control target terminal is performed again from S912, excluding the selected user.

  According to the present embodiment, even when a terminal to which carrier aggregation is applied exists, the same effects as those of the other embodiments can be obtained.

  If the determination in S911 is NO, there is no user who can release the secondary cell, so the flowchart ends.

  However, when the secondary cell cannot be released, the primary cell may be switched. In this case, the process of selecting the control target terminal and the primary cell to be switched to is performed as in FIG.

  In the present embodiment, an example is described in which the user having the largest requested resource amount is selected as the control target user, but the present invention is not limited to this. For example, if the requested resource amount is equal to or more than a predetermined value, an arbitrary user may be selected. Further, a user who has the largest difference between the requested resource amount and the actually used resource amount may be selected. Alternatively, the number of component carriers in use may be selected from two or more users.

  In this embodiment, an example in which the secondary cell is released as the frequency band reselection has been described, but the present invention is not limited to this. For example, in addition to the release of the secondary cell, a secondary cell may be newly added to a frequency band having a surplus resource amount of 0 or more in the first embodiment.

  Further, the secondary cell may be switched to another frequency band without changing the number of component carriers used by the terminal. Here, for example, “switching” may mean that the terminal uses the first component carrier, releases the first component carrier, and selects a second component carrier to be a secondary cell. .

  In this case, similarly to FIG. 4, a control target terminal and a component carrier (frequency band) to be a secondary cell to be switched to may be selected.

  For the control target terminal, the frequency band of the reconnection destination is not newly selected, and the number of frequency bands to be used (in units) is reduced.

  In the present embodiment, one component carrier may be called one frequency band. For example, a predetermined 20 Mhz bandwidth included in the 2 GHz band can be set as one frequency band. Further, the component carrier to be selected may be selected from a continuous band (Intra-band) or may be selected from a discontinuous band (Inter-band). For example, a component carrier can be selected only from the 2 GHz band. Further, for example, a component carrier can be selected from the 800 MHz band and the 2 GHz band.

<Fifth embodiment>
FIG. 11 illustrates a base station device according to the fifth exemplary embodiment.

  Base station apparatus 1100 includes a plurality of frequency bands.

  The base station device 1100 has a transceiver 1101 and a processor 1102. The transceiver 1101 is configured to communicate with the terminal device 3 using at least one of a plurality of frequency bands.

  The processor 1102 is configured to calculate a radio resource to satisfy the requirement in at least one frequency band based on a requirement regarding communication quality required for an application used by the terminal device 3. In addition, the processor 1102 is configured to select a frequency band for the terminal device 3 from a plurality of frequency bands based on the calculated radio resources. Note that the processor 1102 may be configured to select a frequency band for the terminal device 3 from a plurality of frequency bands when the calculated radio resource exceeds a predetermined value.

  Note that the above requirements may be created by the processor 1102. In this case, the processor 1102 may be configured to select a frequency band satisfying the created requirement from the plurality of frequency bands.

  FIG. 12 shows a modification of the base station apparatus according to the fifth exemplary embodiment.

  The base station device 1200 according to the modified example includes a transceiver 1201, a memory 1202, and a processor 1203.

  Base station apparatus 1200 includes a plurality of frequency bands.

  The transceiver 1201 is configured to communicate with the terminal device 3 using at least one of a plurality of frequency bands.

  The memory 1202 is configured to store requirements regarding communication quality required for an application used by the terminal device 3.

  The processor 1203 is configured to calculate a radio resource to satisfy the stored requirement in at least one frequency band. In addition, the processor 1203 is configured to select a frequency band for the terminal device 3 from a plurality of frequency bands based on the calculated radio resources. Note that the processor 1203 may be configured to select a frequency band for the terminal device 3 from a plurality of frequency bands when the calculated radio resource exceeds a predetermined value.

  FIG. 13 shows a relay device according to the fifth exemplary embodiment.

  The relay device 1300 includes a transmitter 1301 and a processor 1302.

  Relay apparatus 1300 is configured to relay communication between a base station apparatus configured to communicate with a terminal apparatus using at least one of a plurality of frequency bands and an upper network.

  The processor 1302 is configured to create a requirement regarding communication quality required for an application used by the terminal device.

  The transmitter 1301 is configured to transmit the created requirement to the base station device.

  Here, the requirement enables the base station device to perform the following operation. The operation is to calculate a radio resource to satisfy the requirement and to select a frequency band for the terminal device from a plurality of frequency bands based on the calculated radio resource. Note that this operation may be such that, when the calculated radio resource exceeds a predetermined value, a frequency band for the terminal device is selected from a plurality of frequency bands.

<Sixth exemplary embodiment>
FIG. 14 shows a sixth exemplary embodiment.

  The base station device 1400 according to the present embodiment includes a transceiver 1401 and a processor 1402.

  The transceiver 1401 performs wireless communication related to an application used by the terminal device using the first frequency band.

  The processor 1402 changes the frequency band connected to the terminal device 3 from the first frequency band to the second frequency band based on the information on the quality required for the application and the information on the quality of the wireless communication. Be composed.

<Other embodiments>
Also, while the embodiments have been described with reference to an LTE-based wireless communication system, at least some of the methods and apparatus of the various embodiments may be implemented in a wide range of communications including many non-LTE and / or non-cellular systems. Applicable to the system. For example, the above embodiment may be a UMTS (Universal Mobile Telecommunications System) system. Further, the above embodiment may be a wireless communication system that employs an FDD (Frequency Division Duplex) scheme that simultaneously uses different frequencies for the uplink and the downlink. Also, the above embodiments employ different wireless communication systems (e.g., WiFi, WiMAX (Worldwide interoperability for Microwave Access), IEEE, and the like) adopting a TDD (Time Division Duplex) scheme in which the same frequency is used at different times in uplink and downlink. 802.16m).

  The small cell in the above embodiment indicates a narrow coverage area (cell) formed by low transmission power transmitted by the base station. In the above embodiment, the small cells are overlaid on the macro cells. However, the relationship may cover an area outside the coverage of the macro cell. The small cell base station may be provided, for example, in a hot spot where terminals are concentrated or indoors where wireless quality is often poor.

  The above embodiments relate to frequency band selection performed in a Heterogeneous network environment where cells of different sizes and frequencies (frequency bands) coexist. According to the above embodiment, in an environment where traffic of different applications coexist, if the applications are biased among the frequency bands, the frequency band is reselected, so that the user experience quality QoE can be improved.

  The above-mentioned frequency band may include at least one of arbitrary frequency bands. For example, a high frequency band such as a 3.5 GHz band may be used in addition to an already operated frequency band such as an 800 MHz band or a 2 GHz band, but is not limited thereto. For example, when a high frequency band is selected, higher-speed and larger-capacity communication becomes possible.

  In addition, a predetermined bandwidth included in a specific frequency band, such as a component carrier of carrier aggregation, may be referred to as a frequency band. For example, the selected frequency band may be a frequency band assigned to each communication standard or each operator.

  Note that the QoS described above indicates the service quality of the network. For example, the QoS may be a measure of the quality of service as viewed from a communication carrier or a service provider, such as packet loss, packet delay, fluctuation of packet arrival time, and the like. The QoE may be a measure of the quality of service of the application as seen by the user, such as the time during which a moving image is interrupted or the time during which a Web is downloaded.

  Note that selecting a cell may be read as selecting a frequency band used for the cell.

  The above embodiment is not limited to the Web application and the moving image application. The above exemplary embodiments may include any application that may be subject to app quality requirements. For example, the embodiment may include various applications such as social networking service (SNS), voice over IP (VoIP), and an application for exchanging files.

  The above-mentioned terminals can also be called wireless terminals, mobile terminals or user terminals (or users). The terminal may also be a system, subscriber unit, subscriber station, mobile station, wireless terminal, mobile device, node, device, remote station, remote terminal, wireless communication device, wireless communication device, wireless communication device or user agent function. It may include some or all of the gender. Terminals include cellular phones, cordless phones, Session Initiation Protocol (SIP) phones, smartphones, wireless local loop (WLL) stations, personal digital assistants (PDAs), laptops, tablets, netbooks, smartbooks, handheld communication devices, and handhelds It may be a computing device, a satellite radio, a wireless modem card and / or another processing device communicating via a wireless system. In the above embodiment, an example in which the terminal operator owns one terminal has been described, but the present invention is not limited to this. One terminal may be shared by a plurality of operators.

  Further, the small cell base station can be simply referred to as a base station. A base station can be used for communication with one or more wireless terminals and includes some or all of the functionality of an access point, node, evolved Node B (eNB), or some other network entity. obtain. The base station communicates with the UE via the air interface. This communication may occur through one or more sectors. The base station may act as a router between the UE and the rest of the access network, which may include an Internet Protocol (IP) network, by converting received air interface frames into IP packets. The base station may also coordinate management of attributes for the air interface and may be a gateway between the wired and wireless networks.

  Further, according to at least one of the methods and apparatuses of the above-described embodiments, it becomes possible to flexibly allocate radio resources when the system becomes complicated due to introduction of small cells or expansion of frequency bands. . As a result, QoE can be maintained or improved.

  According to at least one of the methods and apparatuses of the above-described embodiments, it is possible to correct the bias of the required value of the radio resource between the frequency bands and improve the QoE that has been reduced due to the concentration of the same application. .

  Furthermore, the present invention is not limited to only the above-described embodiment, and it is needless to say that various modifications can be made without departing from the spirit of the present invention. The functions or steps and / or actions according to each embodiment described herein need not be performed in any particular order. Further, elements of the invention may be described or claimed in the singular, but may be in the plural unless explicitly stated to limit it to the singular.

<Appendix>
Some or all of the above-described embodiments can be described as in the following supplementary notes. However, the following supplementary notes are merely examples of the present invention, and the present invention is not limited to only such cases.

(Appendix 1)
A control method in a wireless communication system including a base station device having a plurality of frequency bands and a terminal device configured to communicate with the base station device,
Based on the requirements regarding communication quality required for the application used by the terminal device,
In at least one frequency band among the plurality of frequency bands, calculate a radio resource to satisfy the requirement,
When the calculated radio resource exceeds a first predetermined value, a frequency band for the terminal device is selected from the plurality of frequency bands,
Control method.
(Appendix 2)
The first predetermined value is:
The radio resource in the selected frequency band, a value related to the difference between the radio resources in the frequency band other than the selected frequency band,
The control method according to supplementary note 1.
(Appendix 3)
The calculation is
For each terminal device using one frequency band included in the at least one frequency band, calculating a required resource amount that is a resource amount to satisfy the requirement, and one included in the at least one frequency band For each frequency band, obtaining a total value by summing the requested resource amount,
including,
The control method according to Supplementary Note 1 or 2.
(Appendix 4)
The selection is
Selecting a frequency band whose sum satisfies a predetermined condition,
3. The control method according to supplementary note 3, comprising:
(Appendix 5)
The predetermined condition is
A surplus resource amount, which is a resource amount obtained by subtracting the total value from a predetermined threshold value, is equal to or more than a second predetermined value;
4. The control method according to claim 4, wherein
(Appendix 6)
The predetermined condition is
The total value is smaller than the total value of the frequency bands to which the terminal device is connected before the selection,
4. The control method according to claim 4, wherein
(Appendix 7)
The terminal device from which the frequency band is selected,
The frequency band using the total value exceeds the predetermined threshold,
7. The control method according to any one of supplementary notes 3 to 6.
(Appendix 8)
The selection is
Selecting the terminal device whose resource amount obtained by subtracting the required resource amount from the surplus resource amount is equal to or less than a third predetermined value,
8. The control method according to supplementary note 7, comprising:
(Appendix 9)
The requirements are:
Including a target value of throughput set based on the identification index that identifies the type of application,
The control method according to supplementary note 1.
(Appendix 10)
The identification index is
10. The control method according to supplementary note 9, which is a QoS Class Identifier (QCI), which is an identification index of a QoS (Quality of Service).
(Appendix 11)
The requirements are:
Created by a relay device that relays the base station device and the upper network,
The requirements are:
Based on traffic for each application, which is transferred via the relay device,
The control method according to supplementary note 1.
(Appendix 12)
The requirements are:
At least one of the following that is required for each application to maintain Quality of Experience (QoE):
throughput,
Delay time,
The transmission data size that needs to be received at a given time, or
Time and frequency of interruption of the application,
12. The control method according to supplementary note 9 or 11.
(Appendix 13)
The frequency band used by the terminal device,
From the frequency band used before the selection, is switched to the selected frequency band,
13. The control method according to any one of supplementary notes 1 to 12.
(Appendix 14)
The selected frequency band is
Used by the terminal device to start a new wireless communication with the base station device,
The control method according to supplementary note 1.
(Appendix 15)
In the case where the selected frequency band is used as the secondary cell and the terminal device is used,
The required resource amount in the terminal device is equal to or greater than a fourth predetermined value;
7. The control method according to any one of supplementary notes 3 to 6.
(Appendix 16)
Selecting the frequency band comprises:
Releasing the secondary cell,
The control method according to supplementary note 15.
(Appendix 17)
The terminal device in which the frequency band is selected,
The total value is connected as a primary cell to the frequency band exceeding the predetermined threshold, and,
The control method according to any one of supplementary notes 3 to 6, wherein the terminal device has a resource amount obtained by subtracting the required resource amount from the surplus resource amount in the connected frequency band, which is equal to or less than a fifth predetermined value.
(Appendix 18)
The terminal device from which the frequency band is selected,
The total value is connected to the frequency band exceeding the predetermined threshold,
And,
7. The control method according to any one of Supplementary Notes 3 to 6, wherein the terminal device has two or more frequency bands connected simultaneously.
(Appendix 19)
A base station device having a plurality of frequency bands,
A transceiver configured to communicate with a terminal device using at least one of the plurality of frequency bands,
Based on the requirements regarding communication quality required for the application used by the terminal device,
In the at least one frequency band, calculate a radio resource to satisfy the requirement,
A processor configured to, when the calculated radio resource exceeds a first predetermined value, select a frequency band for the terminal device from the plurality of frequency bands;
A base station device comprising:
(Appendix 20)
A relay device,
A base station device configured to communicate with the terminal device using at least one of the plurality of frequency bands, and configured to relay communication between the upper network,
A processor that creates requirements regarding communication quality required for an application used by the terminal device,
A transmitter configured to transmit the created requirement to the base station device,
The requirements are:
The base station device,
Calculate radio resources to meet the requirements,
When the calculated radio resource exceeds a first predetermined value, selecting a frequency band for the terminal device from the plurality of frequency bands;
Enable
Relay device.
(Appendix 21)
In a wireless communication system having a terminal device and a base station device having a plurality of frequency bands,
The terminal device,
Using at least one of the plurality of frequency bands, configured to communicate with the base station device,
The base station device,
Based on the requirements regarding communication quality required for the application used by the terminal device,
In the at least one frequency band, calculate a radio resource to satisfy the requirement,
When the radio resource exceeds a first predetermined value, a frequency band for the terminal device is configured to be selected from the plurality of frequency bands.
Wireless communication system.
(Appendix 22)
For an application used by a terminal device configured to be able to communicate with a base station device having a plurality of frequency bands, based on requirements for required communication quality,
In the at least one frequency band, calculate a radio resource to satisfy the requirement,
When the calculated radio resource exceeds a first predetermined value, selecting a frequency band for the terminal device from the plurality of frequency bands,
A program to be executed by a computer.
(Appendix 23)
A base station device having a plurality of frequency bands,
A transceiver configured to communicate with a terminal device using at least one of the plurality of frequency bands,
Create requirements regarding the communication quality required for the application used by the terminal device,
In the at least one frequency band, calculate a radio resource to satisfy the requirement,
A processor configured to, when the calculated radio resource exceeds a first predetermined value, select a frequency band for the terminal device from the plurality of frequency bands;
A base station device comprising:
(Appendix 24)
A base station device having a plurality of frequency bands,
A transceiver configured to communicate with a terminal device using at least one of the plurality of frequency bands,
A memory for storing requirements regarding communication quality required for an application used by the terminal device,
In the at least one frequency band, calculate radio resources to meet the stored requirements,
A processor configured to select a frequency band for the terminal device from the plurality of frequency bands based on the case where the calculated radio resource exceeds a first predetermined value;
A base station device comprising:
(Appendix 25)
A base station device having a plurality of frequency bands,
A transceiver configured to communicate with a terminal device using at least one of the plurality of frequency bands,
Create requirements regarding the communication quality required for the application used by the terminal device,
A processor configured to select a frequency band that satisfies the requirement from the plurality of frequency bands,
A base station device comprising:
(Supplementary Note 26)
A transceiver configured to perform wireless communication related to an application used by the terminal device using the first frequency band;
Based on information related to the quality required for the application and information related to the quality of the wireless communication,
A processor configured to change a frequency band to which the terminal device connects from the first frequency band to a second frequency band;
A base station device having:

DESCRIPTION OF SYMBOLS 1 Upper network 2 Small cell base station 3, 3-1 and 3-2 Terminal 4 Relay device 201 First transmitting / receiving unit 202 Second transmitting / receiving unit 203 Application quality requirement creation unit 204 Aggregation unit 205 First selection unit 206 2 selecting unit 301 transmitting / receiving unit 401 application quality requirement creating unit 1100, 1200, 1400 base station device 1101, 1201, 1401 transceiver 1102, 1203, 1402 processor 1202 memory 1300 relay device 1301 transmitter 1302 processor

Claims (10)

A control method in a wireless communication system including a base station device having a plurality of frequency bands and a terminal device configured to communicate with the base station device,
Based on the requirements regarding communication quality required for the application used by the terminal device,
In at least one first frequency band of the plurality of frequency bands, calculate a radio resource to satisfy the requirement,
When the calculated radio resource in the first frequency band exceeds a first predetermined value , of the plurality of frequency bands, a second frequency band different from the first frequency band, to Menisen-option was of the terminal device,
Control method. The first predetermined value is:
A value obtained by multiplying the total radio resource amount of the first frequency band by a predetermined ratio ,
The control method according to claim 1. The calculation is
For each terminal device using a pre-Symbol first frequency band, calculating the amount of the requested resource is a resource amount to meet the requirements, and pre-SL for each first frequency band, the amount of the requested resource Obtaining the total value by summing,
including,
The control method according to claim 1. In each of the second frequency bands, the required resource amount is calculated, and a surplus resource amount which is a resource amount obtained by subtracting a total value of the required resource amount from the first predetermined value is calculated;
The selection is
Performing based on the surplus resource amount ,
The control method according to claim 3, comprising: The requirements are:
Including a target value of throughput set based on the identification index that identifies the type of application,
The control method according to claim 1. The identification index is
QCI (QoS) which is an identification index of QoS (Quality of Service)
The control method according to claim 5, wherein the control method is Class Identifier. The requirements are:
Created by a relay device that relays the base station device and the upper network,
The requirements are:
Based on traffic for each application, which is transferred via the relay device,
The control method according to claim 1. Before the distichum wavenumber band as a secondary cell, in a case where the terminal device is used,
When the total value of the required resource amounts in each of the second frequency bands exceeds the first predetermined value, the second frequency band is excluded from the selection.
The control method according to claim 3 . A base station device having a plurality of frequency bands,
Using at least one of the first frequency band of the plurality of frequency bands, a transceiver configured to communicate with the terminal device,
Based on the requirements regarding communication quality required for the application used by the terminal device,
In the at least one first frequency band, calculate a radio resource to satisfy the requirement,
When the calculated radio resource in the first frequency band exceeds a first predetermined value, of the plurality of frequency bands, a second frequency band different from the first frequency band, a processor configured to Menisen-option was of the terminal device,
A base station device comprising: A relay device,
And a base station device configured to communicate with the terminal device by using at least one of the first frequency band of a plurality of frequency bands,
A processor configured to relay communication with a higher-level network and creating a requirement regarding communication quality required for an application used by the terminal device;
A transmitter configured to transmit the created requirement to the base station device,
The requirements are:
The base station device,
Calculate radio resources to meet the requirements,
When the calculated radio resource in the first frequency band exceeds a first predetermined value, of the plurality of frequency bands, a second frequency band different from the first frequency band, Selecting for the terminal device ;
Enable
Relay device.

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