WO2014016861A1 - Wireless communication method, wireless communication system, base station and wireless terminal - Google Patents

Wireless communication method, wireless communication system, base station and wireless terminal Download PDF

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Publication number
WO2014016861A1
WO2014016861A1 PCT/JP2012/004672 JP2012004672W WO2014016861A1 WO 2014016861 A1 WO2014016861 A1 WO 2014016861A1 JP 2012004672 W JP2012004672 W JP 2012004672W WO 2014016861 A1 WO2014016861 A1 WO 2014016861A1
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WO
WIPO (PCT)
Prior art keywords
transmission
base station
wireless terminal
information
line
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PCT/JP2012/004672
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French (fr)
Japanese (ja)
Inventor
伊藤　章
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富士通株式会社
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Publication date
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Priority to PCT/JP2012/004672 priority Critical patent/WO2014016861A1/en
Publication of WO2014016861A1 publication Critical patent/WO2014016861A1/en

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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W48/00—Access restriction; Network selection; Access point selection
    • H04W48/02—Access restriction performed under specific conditions
    • H04W48/06—Access restriction performed under specific conditions based on traffic conditions

Definitions

  • the present invention relates to a wireless communication method, a wireless communication system, a base station, and a wireless terminal.
  • next-generation wireless communication technologies have been discussed in order to further increase the speed and capacity of wireless communication in wireless communication systems such as mobile phone systems.
  • 3GPP 3rd Generation Partnership Project
  • LTE Long Term Evolution
  • LTE-A LTE-Advanced
  • a connection is established by accessing a base station using RACH (Random Access Channel), and data transmission is started.
  • RACH Random Access Channel
  • data transmission is started.
  • the base station is accessed using the RACH, or the PUCCH (Physical Uplink Control Channel) allocated in advance is used. Or start sending data.
  • PUCCH Physical Uplink Control Channel
  • the wireless terminal tries to access the base station every time transmission data is generated as described above, it cannot be accessed due to line congestion, data cannot be transmitted, and signaling for access is wasted. There is a fear. In addition, this signaling may further hinder other accesses.
  • the disclosed technology has been made in view of the above, and in a wireless communication system, a wireless communication method, a wireless communication system, a base station, and a wireless terminal capable of efficiently controlling access from a wireless terminal and improving communication performance
  • the purpose is to provide.
  • the wireless communication method disclosed in the present application notifies the wireless terminal of information related to the state of the line, and the wireless terminal transmits data to the base station.
  • the error occurs, it is controlled whether or not to hold the transmission to the base station based on the information on the state of the line and the characteristics of the transmission data.
  • the wireless communication method disclosed in the present case it is possible to efficiently control access from a wireless terminal and improve communication performance in a wireless communication system.
  • FIG. 1 is a diagram illustrating a configuration of a wireless communication system according to the first embodiment.
  • FIG. 2 is a functional block diagram showing the configuration of the base station according to the first embodiment.
  • FIG. 3 is a functional block diagram showing the configuration of the wireless terminal according to the first embodiment.
  • FIG. 4 is a diagram illustrating a hardware configuration of the base station according to the first embodiment.
  • FIG. 5 is a diagram illustrating a hardware configuration of the wireless terminal according to the first embodiment.
  • FIG. 6 is a sequence diagram for explaining the operation of the wireless communication system according to the first embodiment.
  • FIG. 7 is a functional block diagram showing the configuration of the base station of the wireless communication system according to the second embodiment.
  • FIG. 1 is a diagram illustrating a configuration of a wireless communication system according to the first embodiment.
  • FIG. 2 is a functional block diagram showing the configuration of the base station according to the first embodiment.
  • FIG. 3 is a functional block diagram showing the configuration of the wireless terminal according to the first embodiment.
  • FIG. 8 is a functional block diagram showing a configuration of a wireless terminal of the wireless communication system according to the second embodiment.
  • FIG. 9 is a sequence diagram for explaining the operation of the radio communication system according to the second embodiment.
  • FIG. 10 is a sequence diagram for explaining the operation of the wireless communication system according to the third embodiment.
  • FIG. 11 is a sequence diagram for explaining the operation of the wireless communication system according to the fourth embodiment.
  • FIG. 1 shows a configuration of a wireless communication system 1 according to the first embodiment.
  • the radio communication system 1 includes a base station 10 and radio terminals 20A and 20B.
  • the base station 10 forms a cell C10.
  • the radio terminals 20A and 20B exist in the cell C10.
  • the base station 10 is connected to the network device 3 via a wired connection, and the network device 3 is connected to the network 2 via a wired connection.
  • the base station 10 is provided so as to be able to transmit and receive data and control information to and from other base stations via the network device 3 and the network 2.
  • the network device 3 includes, for example, a communication unit and a control unit, and these components are connected so that signals and data can be input and output in one direction or in both directions.
  • the network device 3 is realized by a gateway, for example.
  • the communication unit is realized by an interface circuit
  • the control unit is realized by a processor and a memory.
  • FIG. 2 is a functional block diagram showing the configuration of the base station 10. As shown in FIG. 2, the base station 10 includes a transmission unit 11, a reception unit 12, and a control unit 13. Each of these components is connected so that signals and data can be input and output in one direction or in both directions.
  • the transmission unit 11 transmits a data signal and a control signal via an antenna.
  • the transmitter 11 transmits a downlink signal via, for example, a downlink data channel or a control channel.
  • the downlink physical data channel includes, for example, a dedicated data channel PDSCH (Physical Downlink Shared Channel).
  • the downlink physical control channel includes a dedicated control channel PDCCH (PhysicalPhysDownlink Control Channel).
  • the signal to be transmitted includes, for example, information regarding the line status at the base station 10 and release information for releasing the suspension of transmission at the radio terminals 20A and 20B. For example, information related to the line status is broadcast as broadcast information into the cell C10 formed by the base station 10.
  • the release information is notified to a wireless terminal in a standby state (Idle Mode) via a PCH (Paging Channel) signal.
  • the PCH is a downlink transport channel that transfers information in the cell C10 all at once.
  • the PCH signal is used, for example, to call a wireless terminal when a call arrives at the wireless terminal.
  • the release information is notified to a wireless terminal in a connected state (Connected Mode) via PDCCH order or RRC (Radio Resource Control) message.
  • PDCCH order is an L1 / L2 control signal transmitted to the connected wireless terminal via the dedicated control channel, and is used for the wireless terminal to establish uplink synchronization, for example.
  • the RRC message is an upper layer control signal transmitted via a dedicated data channel to a connected wireless terminal.
  • the receiving unit 12 receives data signals and control signals transmitted from the wireless terminals 20A and 20B via an antenna.
  • the receiving unit 12 receives an uplink signal via, for example, an uplink data channel or a control channel.
  • the uplink physical data channel includes, for example, a dedicated data channel PUSCH (Physical Uplink Shared Channel).
  • the uplink physical control channel includes a dedicated control channel PUCCH.
  • the received signal includes, for example, a RACH signal transmitted from the radio terminals 20A and 20B.
  • RACH is a transport channel for transmitting a signal for wireless terminals to perform random access.
  • the RACH signal is a signal transmitted from a wireless terminal in a random access procedure.
  • the base station 10 receives the RACH signal and exchanges information, thereby recognizing the wireless terminal and managing information on the wireless terminal connected to the own station.
  • the antenna may be common for transmission and reception.
  • the control unit 13 acquires data and control information from the network device 3 and other base stations via a wired connection or a wireless connection.
  • the control unit 13 outputs data to be transmitted and control information to the transmission unit 11.
  • the control unit 13 inputs received data and control information from the reception unit 12.
  • the control unit 13 determines the line status at the base station 10 and notifies the wireless terminal of information related to the line status.
  • Examples of the information regarding the line status include line congestion information indicating whether or not the line is congested.
  • the line congestion information includes, for example, the line congestion level.
  • the degree of line congestion is set in two stages: “line is congested” and “line is not congested”.
  • the congestion level of the line is not limited to two stages, and can be set arbitrarily.
  • the congestion level of the line is, for example, the number of wireless terminals in uplink communication in the cell C10 formed by the base station 10, the number of wireless terminals in downlink communication, and the uplink to be transmitted from the wireless terminals in the cell C10 to the base station 10 This is determined based on at least one of the transmission data amount and the downlink transmission data amount to be transmitted from the base station 10 to the radio terminal in the cell C10.
  • control unit 13 determines whether or not to cancel the hold of the wireless terminal holding data transmission, and transmits the release information to the wireless terminals 10A and 10B.
  • the determination of the release of the hold is executed, for example, when notifying information indicating that the line is congested. Whether or not to cancel the hold is determined based on, for example, information related to the line status of the base station 10. For example, when it is determined that the line is not congested, the control unit 13 determines to cancel the hold.
  • the hold cancellation determination condition and the line congestion determination condition may be the same condition or different conditions.
  • FIG. 3 is a functional block diagram showing the configuration of the wireless terminal 20A.
  • the radio terminal 20 ⁇ / b> A includes a transmission unit 21, a reception unit 22, and a control unit 23. Each of these components is connected so that signals and data can be input and output in one direction or in both directions.
  • the functional configuration and hardware configuration of the wireless terminal 20B are the same as the functional configuration and hardware configuration of the wireless terminal 20A.
  • the transmission unit 21 transmits a data signal and a control signal via an antenna.
  • the transmission unit 21 transmits an uplink signal via, for example, an uplink data channel or a control channel.
  • the signal to be transmitted includes, for example, a RACH signal.
  • the radio terminal 20A transmits a RACH signal and exchanges information for establishing a connection with the base station 10 according to a random access procedure.
  • the receiving unit 22 receives data signals and control signals transmitted from the base station via an antenna.
  • the received signal includes, for example, information on the line status and release information for releasing the transmission suspension.
  • the antenna may be common for transmission and reception.
  • the control unit 23 outputs data to be transmitted and control information to the transmission unit 21. In addition, the control unit 23 inputs data and control information received from the receiving unit 22.
  • the control unit 23 determines whether or not to hold the transmission to the base station 10 based on the received information on the status of the line and the characteristics of the transmission data. to decide. In addition, the control unit 23 releases the suspension of transmission according to the received release information, and starts transmission of transmission data to the base station 10.
  • the control unit 23 determines whether or not to hold transmission when transmission data is generated.
  • the characteristics of the transmission data include, for example, the priority of the transmission data.
  • the priority of the transmission data is determined based on, for example, at least one of the type of service set in the radio terminal 20A, the type of application using the transmission data, the logical channel number of the transmission data, and the allowable delay time of the transmission data. Is done.
  • the control unit 23 determines that the transmission is not suspended, transmits a RACH signal, establishes a connection, and transmits the transmission data. Start sending. For example, the control unit 23 determines that the transmission is not suspended when the congestion level of the line is equal to or higher than a predetermined level (the line is congested) and the priority of the transmission data is equal to or higher than the predetermined level.
  • a RACH signal is transmitted to establish a connection, and transmission of transmission data is started.
  • the control unit 23 determines that the transmission is suspended, does not transmit the RACH signal, and transmits the transmission data. Do not start.
  • control unit 23 when receiving the release information when the transmission is suspended, releases the suspension of transmission, transmits a RACH signal, establishes a connection, and transmits the suspended transmission data. Start sending.
  • FIG. 4 is a diagram illustrating a hardware configuration of the base station 10.
  • the base station 10 includes, as hardware components, an RF (Radio Frequency) circuit 32 including an antenna 31, a CPU (Central Processing Unit) 33, a DSP (Digital Signal Processor) 34, and the like. , A memory 35 and a network IF (Interface) 36.
  • the CPU is connected via a network IF 36 such as a switch so that various signals and data can be input and output.
  • the memory 35 includes at least one of RAM (Random Access Memory) such as SDRAM (Synchronous Dynamic Random Access Memory), ROM (Read Only Memory), and flash memory, and stores programs, control information, and data.
  • the transmitter 11 and the receiver 12 are realized by an antenna 31 and an RF circuit 32, for example.
  • the control unit 13 is realized by, for example, an integrated circuit such as the CPU 33 or an integrated circuit such as the DSP 34.
  • FIG. 5 is a diagram illustrating a hardware configuration of the wireless terminal 20A.
  • the radio terminal 20 ⁇ / b> A includes, as hardware components, for example, an RF circuit 42 including an antenna 41, a CPU 43, and a memory 44.
  • the radio terminal 20 ⁇ / b> A may include a display device such as an LCD (Liquid Crystal Display) connected to the CPU 43.
  • the memory 44 includes at least one of RAM such as SDRAM, ROM, and flash memory, for example, and stores programs, control information, and data.
  • the transmitter 21 and the receiver 22 are realized by an antenna 41 and an RF circuit 42, for example.
  • the control unit 23 is realized by an integrated circuit such as the CPU 43, for example.
  • FIG. 6 is a sequence diagram for explaining a data transmission operation in the radio terminals 20A and 20B in the radio communication system 1.
  • a wireless terminal in which transmission data is generated accesses the base station 10 each time.
  • a RACH signal is transmitted to the base station 10 to execute a random access procedure, a transition is made to Connected ⁇ ⁇ Mode, a connection is established, and transmission of transmission data is started To do.
  • the RACH signal is transmitted to the base station 10 to execute a random access procedure, uplink synchronization is established, and transmission of transmission data is started.
  • the base station when new transmission data is generated in a wireless terminal in Connected Mode, the base station is accessed using the PUCCH assigned to the wireless terminal in advance, and transmission of transmission data is started. In this case, in any case, the operation always accesses the base station 10.
  • the wireless terminal can access the base station and transmit data.
  • the base station 10 cannot be accessed due to the line congestion, and data may not be transmitted. In this case, signaling for access may be wasted, or other access may be hindered by this signaling.
  • the state of the line changes with time, and it is considered that a time when the degree of congestion is relatively high and a time when the degree of congestion is relatively low are mixed.
  • Various characteristics are assumed for the transmission data. For example, depending on the type of application that uses the transmission data, there may be a case where immediacy is required or a certain amount of waiting.
  • the data transmission operation from the wireless terminal is performed as follows.
  • the wireless terminals 20A and 20B are in a standby state or a connected state, and a line is congested in the base station 10. Further, it is assumed that transmission data generated in the radio terminal 20A has a relatively high priority, and transmission data generated in the radio terminal 20B has a relatively low priority.
  • the base station 10 determines the line status (S1). For example, the base station 10 determines whether or not the line is congested. The determination of the line status is repeatedly executed, for example, at predetermined intervals.
  • the base station 10 notifies the wireless terminal of information related to the line status (S2). For example, the base station 10 notifies line congestion information indicating whether or not the line is congested. Information regarding the line status is repeatedly reported at predetermined intervals in the cell C10, for example.
  • transmission data is generated in the wireless terminals 20A and 20B (S3).
  • the wireless terminals 20A and 20B determine whether or not to hold the transmission based on the information on the line status and the characteristics of the transmission data (S4). For example, when the line is not congested, it is determined that transmission is not suspended. For example, when the line is congested and the priority of the transmission data is relatively high, it is determined that the transmission is not suspended. For example, when the line is congested and the priority of the transmission data is relatively low, it is determined that the transmission is suspended.
  • the radio terminal 20A determines that transmission is not suspended because the line is congested and the priority of transmission data is relatively high. Further, the radio terminal 20B determines that the transmission is not suspended because the line is congested and the priority of the transmission data is relatively low.
  • the base station 10 determines whether or not to cancel the suspension of transmission at the wireless terminal that suspended the transmission (S5). For example, the base station 10 determines whether or not the line is congested. If the base station 10 determines that the line is not congested, the base station 10 determines to cancel the transmission suspension.
  • the base station 10 transmits the cancellation information (S6).
  • the radio terminal 20B performs a release information reception process (S7). Then, the wireless terminal 20B determines whether or not the release information has been received (S8). If the release information has not been received (No in S8), the process returns to S7. Until the determination result in S8 is Yes, the radio terminal 20B performs the release information reception process at predetermined intervals. As a result, transmission suspension is continued.
  • the wireless terminal 20B releases the suspension of transmission, proceeds to S9, and starts data transmission.
  • the wireless terminal 20B releases the suspension of transmission, proceeds to S9, and starts data transmission.
  • the wireless terminal 20B releases the suspension of transmission, proceeds to S9, and starts data transmission.
  • the first embodiment it is possible to efficiently control access from a wireless terminal and improve communication performance in the wireless communication system 1.
  • the release information may be notified to all the wireless terminals under the base station 10 or may be notified for each wireless terminal.
  • an access time after release of the hold may be set and notified by being included in the release information.
  • the base station 10 may group the wireless terminals 20A and 20B, determine release of transmission suspension for each group, and notify the release information. According to this, since the suspension of transmission is released at a different timing for each group, for example, it is possible to avoid the possibility that the line is congested, compared to the case where the suspension of transmission of wireless terminals is released all at once. .
  • the release information and the group identification information are notified from the base station 10 to the wireless terminals 20A and 20B.
  • the group identification information is information for identifying wireless terminals included in the group. Based on the group identification information, the wireless terminals 20A and 20B acquire release information addressed to the group including the device itself, release the transmission suspension, and start data transmission.
  • the base station 10 transmits the release information at a different timing for each group, and the radio terminals 20A and 20B include the own device by receiving the release information at the timing addressed to the group including the own device.
  • Release information addressed to a group may be acquired.
  • timing information addressed to the group is notified in advance.
  • the group identification information may be notified in advance by broadcast information or the like, and the base station 10 may notify the cancellation information using the group identification information after masking.
  • the radio terminals 20A and 20B can acquire the release information addressed to the group including the own device by processing a signal that can include the release information using the group identification information.
  • the wireless communication system according to the second embodiment includes a base station 50 (shown in FIG. 7 described later) and wireless terminals 70A and B (shown in FIG. 8 described later).
  • the overall configuration of the wireless communication system according to the second embodiment is the same as that of the wireless communication system 1 shown in FIG. Portions other than the base station 50 and the wireless terminals 70A and B of the wireless communication system are denoted by the same reference numerals and description thereof is omitted.
  • the wireless terminals 70A and 70B exist in a cell formed by the base station 50.
  • the base station 50 is connected to the network device 3 via a wired connection, and the network device 3 is connected to the network 2 via a wired connection.
  • the base station 50 is provided so as to be able to transmit and receive data and control information to and from other base stations via the network device 3 and the network 2.
  • FIG. 7 is a functional block diagram showing the configuration of the base station 50.
  • the base station 50 includes a reception antenna 51, a reception signal processing unit 52, a data reception unit 53, a data transfer unit 54, a RACH reception unit 55, and a line establishment processing unit 56.
  • the base station 50 includes a line congestion determination unit 57, a data transmission unit 58, a release information transmission unit 59, a transmission signal processing unit 60, and a transmission antenna 61. Each of these components is connected so that signals and data can be input and output in one direction or in both directions.
  • the receiving antenna 51 receives a radio signal and outputs it to the received signal processing unit 52.
  • the base station 50 may include a plurality of receiving antennas. Further, the base station 50 may share an antenna for transmission and reception, and switch between using an antenna duplexer.
  • the receiving antenna 51 receives an upstream signal via, for example, an upstream data channel or a control channel.
  • Physical channels that receive signals include, for example, PRACH (PhysicalPhysRandom Access Channel), PUSCH, and PUCCH.
  • the uplink signal includes, for example, a RACH signal, a reference signal, a control signal, and a data signal.
  • the reception signal processing unit 52 performs wireless processing such as A / D (Analog-to-Digital) conversion and digital signal processing such as FFT processing on the reception signal.
  • the reception signal processing unit 52 outputs the received data signal, control signal, and reference signal to the data reception unit 53.
  • the reception signal processing unit 52 outputs the received RACH signal to the RACH reception unit 55.
  • the data receiving unit 53 performs demodulation processing and decoding processing on the received data signal and control signal. For example, the data receiving unit 53 performs demodulation processing based on control information notified or stored in advance and a reference signal for demodulation processing. Further, the data receiving unit 53 performs a decoding process on the demodulated signal based on the control information notified or stored in advance and the channel estimation value estimated from the reference signal for channel estimation. .
  • the data transfer unit 54 performs a reordering process or the like of the decoded signal, and transfers the acquired received data to the network device 3. In addition, the data transfer unit 54 outputs reception quality acquired from the received signal, control information, and the like to each unit of the base station 50.
  • the RACH receiving unit 55 acquires the RACH preamble from the RACH signal and outputs it to the line establishment processing unit 56.
  • the RACH signal is a signal transmitted from the wireless terminals 70A and B in a random access procedure.
  • the base station 50 receives the RACH signal and exchanges information, thereby recognizing the wireless terminal and managing information on the wireless terminal currently connected to the base station 50.
  • the line establishment processing unit 56 performs a random access procedure based on the received RACH preamble.
  • the line establishment processing unit 56 manages information on wireless terminals currently connected to the base station 50. For example, identification information of a connected wireless terminal and assignment information of a wireless resource to the connected wireless terminal are managed.
  • the line congestion determination unit 57 determines whether or not the line is congested. When it is determined that the line is congested, it is determined that transmission is suspended for transmission data having a relatively low priority that occurs in the entire wireless terminals under the base station 50.
  • the line congestion determination unit 57 outputs line congestion information indicating whether or not the line is congested to the data transmission unit 58.
  • the line congestion information includes, for example, the line congestion level.
  • the degree of line congestion is set in two stages: “line is congested” and “line is not congested”.
  • the congestion level of the line is not limited to two stages, and can be set arbitrarily.
  • the congestion level of the line includes, for example, the number of wireless terminals in uplink communication in the cell formed by the base station 50, the number of wireless terminals in downlink communication, and uplink transmission to be transmitted from the wireless terminals in the cell to the base station 50.
  • the determination is based on at least one of the data amount and the downlink transmission data amount to be transmitted from the base station 50 to the radio terminal in the cell.
  • the line congestion determination unit 57 For example, for the uplink, the line congestion determination unit 57, based on the BSR (Buffer Status Report) transmitted from the radio terminal, the uplink transmission data amount that the radio terminal (in the cell) under the base station 50 intends to transmit And congestion of the line can be determined based on the amount of uplink transmission data. Further, for example, the line congestion determination unit 57 can determine the number of wireless terminals that are going to transmit data from the BSR, and determine the line congestion based on the number of wireless terminals. Further, for example, since the downlink data to be transmitted from the upper node (network device 3) to the subordinate radio terminal is transmitted for the uplink, the line congestion determination unit 57 is based on the amount of downlink transmission data. Can be determined.
  • BSR Buffer Status Report
  • the radio terminal to which the downlink transmission data is to be transmitted is designated from the upper node, it is possible to determine the congestion of the line based on the number of radio terminals. For example, even if the amount of transmission data is the same, it is assumed that as the number of wireless terminals increases, the overhead of the control channel increases and the degree of congestion increases.
  • the line congestion determination unit 57 cancels the transmission suspension when the transmission suspension is performed (access restriction is applied) (whether transmission of the suspended transmission data is permitted to start). Determine.
  • the line congestion determination unit 57 determines to cancel the suspension of transmission
  • the line congestion determination unit 57 outputs the cancellation information to the cancellation information transmission unit 59. Whether or not to cancel the hold is performed based on, for example, information regarding the line status of the base station 50. For example, when it is determined that the line is not congested, the line congestion determination unit 57 determines to cancel the hold. Note that the hold cancellation determination condition and the line congestion determination condition may be the same condition or different conditions.
  • the line congestion determination unit 57 determines to what level of priority the data is released from the hold and uses the release information as the release information. May be included.
  • the data transmission unit 58 stores user data and control information in a predetermined signaling format.
  • the data transmission unit 58 performs encoding processing and modulation processing on user data and control information stored in the signaling format, generates transmission data, and outputs the transmission data to the transmission signal processing unit 60.
  • the control information includes broadcast information.
  • the broadcast information includes line congestion information. The line congestion information may be reported only when the line is congested (the degree of congestion is a predetermined level or higher).
  • the data transmission unit 58 generates a reference signal used for data demodulation and channel estimation and outputs the reference signal to the transmission signal processing unit 60.
  • the cancellation information transmission unit 59 generates a PCH signal from the control information and outputs it to the transmission signal processing unit 60.
  • the PCH signal includes release information output from the line congestion determination unit 57.
  • identification information P-RNTI RadioTINetwork Temporary Identifier
  • the PCH signal is transmitted using PDSCH as a physical channel.
  • a release P-RNTI different from the P-RNTI for receiving paging information at the normal time may be used to distinguish from the normal time. This release P-RNTI is notified in advance as broadcast information, for example.
  • the access time of each wireless terminal may be set as a parameter in the PCH signal, and each wireless terminal may randomly select an access slot within the access time, thereby avoiding a RACH signal collision.
  • the transmission signal processing unit 60 generates a transmission signal and outputs it to the transmission antenna 61.
  • the transmission signal processing unit 60 assigns antenna ports and radio resources for transmission data and reference signals, for example.
  • the transmission signal processing unit 60 performs radio processing such as digital signal processing and D / A (Digital-to-Analog) conversion processing to generate a transmission signal.
  • the transmission antenna 61 transmits a radio signal input from the transmission signal processing unit 60.
  • the transmission antenna 61 transmits a downlink signal through, for example, a downlink data channel or a control channel.
  • Physical channels that transmit signals include, for example, a synchronization channel PSCH (Physical Synchronization Channel), a broadcast channel PBCH (Physical Broadcast Channel), PDSCH, and PDCCH.
  • the downlink signal includes a reference signal, a control signal, and a data signal.
  • FIG. 8 is a block diagram showing a functional configuration of the wireless terminal 70A.
  • the functional configuration and hardware configuration of the wireless terminal 70B are the same as the functional configuration and hardware configuration of the wireless terminal 70A.
  • the wireless terminal 70A includes a reception antenna 71, a reception signal processing unit 72, a data reception unit 73, a line congestion determination unit 74, a cancellation information reception unit 75, and a hold cancellation determination unit 76.
  • the wireless terminal 70 ⁇ / b> A includes an application processing unit 77, a transmission buffer 78, a data transmission unit 79, an access control unit 80, a RACH transmission unit 81, a transmission signal processing unit 82, and a transmission antenna 83.
  • the receiving antenna 71 receives a radio signal and outputs it to the received signal processing unit 72.
  • the wireless terminal 70A may include a plurality of reception antennas. Further, the wireless terminal 70A may share an antenna for transmission and reception, and switch between using an antenna duplexer.
  • the reception antenna 71 receives a downlink signal via, for example, a downlink data channel or a control channel.
  • the received signal includes, for example, a PCH signal, a reference signal, a control signal, and a data signal.
  • the reception signal processing unit 72 performs wireless processing such as A / D conversion and digital signal processing such as FFT processing on the reception signal.
  • the reception signal processing unit 72 outputs the received data signal, control signal, and reference signal to the data reception unit 73. Further, the reception signal processing unit 72 outputs the received PCH signal to the cancellation information reception unit 75.
  • the data receiving unit 73 performs demodulation processing and decoding processing on the received data signal and control signal. For example, the data receiving unit 73 performs demodulation processing based on control information notified or stored in advance and a reference signal for demodulation processing. Further, the data receiving unit 53 performs a decoding process on the demodulated signal based on the control information notified or stored in advance and the channel estimation value estimated from the reference signal for channel estimation. .
  • the data receiving unit 73 performs reordering processing of the decoded received signal and extracts data and control information.
  • the extracted data is stored in a buffer, for example.
  • the control information includes notification information, for example.
  • the notification information includes, for example, line congestion information.
  • the release information receiving unit 75 performs demodulation processing and decoding processing on the received PCH signal. Also, the release information receiving unit 75 extracts control information from the reception signal subjected to the decoding process. The extracted control information includes, for example, release information for releasing transmission suspension. The release information receiving unit 75 outputs the received control information to the hold release determining unit 76.
  • PDSCH containing PCH can be received by using P-RNTI to receive PDCCH that is CRC-masked based on P-RNTI. Note that subframes that may contain PCH in the PDSCH are determined in advance.
  • information including release information is stored in a signaling format Paging Message defined by a predetermined signaling format PCCH-message.
  • the hold cancellation determination unit 76 determines whether or not to cancel the transmission hold depending on whether or not the release information is received.
  • the line congestion determination unit 74 determines whether or not the line is congested based on the line congestion information received from the base station 50.
  • the access control unit 80 determines whether or not to instruct suspension of transmission based on the information regarding the state of the line and the characteristics of the transmission data. As the characteristics of the transmission data, for example, the priority of the transmission data can be cited.
  • the access control unit 80 instructs the RACH transmission unit 81 to perform RACH transmission when the broadcast information indicates that the line is not congested (the degree of congestion of the line is less than a predetermined level). Further, the access control unit 80 determines the priority of the transmission data when information indicating that the line is congested (the degree of congestion of the line is equal to or higher than a predetermined level) is obtained from the notification information.
  • the RACH transmission unit 81 When the priority is “high” (priority is equal to or higher than a predetermined level), the RACH transmission unit 81 is instructed to perform RACH transmission. Further, when the priority is “low” (priority is lower than a predetermined level), the access control unit 80 temporarily holds the RACH transmission, and when receiving the release information, the access control unit 80 instructs the RACH transmission unit 81 to perform the RACH transmission. Give instructions.
  • the priority of the transmission data is based on at least one of the type of service set in the wireless terminal 70A, the type of application using the transmission data, the logical channel number of the transmission data, and the allowable delay time of the transmission data. Determine the priority of the transmission data. Specific examples include determination by the following methods and combinations thereof.
  • a number is assigned to a logical channel, and the number is associated with a priority in advance. This association is notified to the application layer (OS, “Operating System”) of the application processing unit 77. For example, No. A immediately starts data transmission (a level with a relatively high priority), and No. B is suspended (a level with a relatively low priority) until an instruction is given.
  • the application layer determines to which logical channel of the communication layer the transmission data is sent according to the application.
  • the application processing unit 77 associates an application with a priority in advance. For example, a high priority is set for an application such as a call that requires real-time performance.
  • the communication layer notifies the application layer whether or not communication of data with a relatively low current priority is possible according to the PCH reception status. Whether the application layer sends data to the communication layer regardless of the communication status if the data has a relatively high priority, and whether to send data to the communication layer according to the communication status if the data has a relatively low priority Judging.
  • a high fee is set when communicating during congestion, and the user wants to start communication at a high fee time for any level of application. It is assumed to set.
  • a service and a priority are associated in advance in consideration of a service (for example, a charge plan) provided to a user.
  • a service for example, a charge plan
  • the priority of transmission data generated by a user (wireless terminal) that has selected a relatively high rate plan is set to be relatively high.
  • the priority can be set to any number of levels as well as two levels of “high” and “low”.
  • the base station can operate by informing the terminal of information indicating whether the priority order is higher than a normal priority level, and a normal transmission start operation is performed, and if the priority level is lower than that level, the transmission is suspended.
  • PCH PCH
  • the application processing unit 77 manages various applications such as telephone calls and data communications executed by the wireless terminal 70A.
  • the application processing unit 77 outputs transmission data generated by application processing to the transmission buffer 78.
  • the transmission buffer 78 stores transmission data output from the application processing unit 77.
  • the data transmission unit 79 stores user data and control information in a predetermined signaling format. Then, the data transmission unit 79 performs encoding processing and modulation processing on the user data and control information stored in the signaling format, and outputs them to the transmission signal processing unit 82. In addition, the data transmission unit 79 generates a reference signal used for data demodulation and channel estimation and outputs the reference signal to the transmission signal processing unit 82. Further, the data transmission unit 79 generates a control signal and outputs it to the transmission signal processing unit 82.
  • the RACH transmission unit 81 generates a RACH signal for a random access procedure.
  • the wireless terminal 70A exchanges information for call connection with the base station 50 by a random access procedure.
  • the RACH transmission unit 81 generates a predetermined signal sequence as a RACH signal from predetermined random access preamble configuration information.
  • the transmission signal processing unit 82 generates a transmission signal and outputs it to the transmission antenna 83.
  • the transmission signal processing unit 82 allocates antenna ports and radio resources for transmission data and reference signals, for example. Also, the transmission signal processing unit 82 performs radio processing such as digital signal processing and D / A (Digital-to-Analog) conversion processing to generate a transmission signal.
  • the transmission antenna 83 transmits a radio signal input from the transmission signal processing unit 82.
  • the transmission antenna 83 transmits an uplink signal via, for example, an uplink data channel or a control channel.
  • Physical channels that transmit signals include, for example, PRACH, PUSCH, and PUCCH.
  • the uplink signal includes, for example, a RACH signal, a reference signal, a control signal, and a data signal.
  • the wireless terminal 70A may include a plurality of transmission antennas.
  • the hardware configuration of the base station 50 is the same as the hardware configuration of the base station 10 of the first embodiment.
  • the reception antenna 51 of the base station 50, the radio processing function of the reception signal processing unit 52, the radio processing function of the transmission signal processing unit 60, and the transmission antenna 61 are realized by an antenna and an RF circuit, for example.
  • the processing unit 56, the data transmission unit 58, and the release information transmission unit 59 are realized by an integrated circuit such as a CPU, for example.
  • the hardware configuration of the wireless terminal 70A is the same as the hardware configuration of the wireless terminal 20A of the first embodiment.
  • the reception antenna 71 of the wireless terminal 70A, the wireless processing function of the reception signal processing unit 72, the wireless processing function of the transmission signal processing unit 82, and the transmission antenna 83 are realized by, for example, an antenna and an RF circuit.
  • Radio processing function of reception signal processing unit 72 of radio terminal 70A, radio processing function of transmission signal processing unit 82, data reception unit 73, line congestion determination unit 74, release information reception unit 75, and hold release determination unit 76, the application processing unit 77, the transmission buffer 78, the data transmission unit 79, the access control unit 80, and the RACH transmission unit 81 are realized by an integrated circuit such as a CPU, for example.
  • the transmission buffer 78 of the wireless terminal 70A is realized by a memory, for example.
  • FIG. 9 is a sequence diagram for explaining a transmission operation in the wireless terminals 70A and B in the wireless communication system.
  • the wireless terminals 70A and 70B are in a standby state and the base station 50 is in a congested line.
  • the transmission data generated in the wireless terminal 70A has a high priority
  • the transmission data generated in the wireless terminal 70B has a low priority.
  • the base station 50 determines whether or not the line is congested (S21).
  • the determination of the congestion of the line is repeatedly executed at a predetermined interval, for example.
  • the base station 50 notifies the wireless terminal 70A, B of the line congestion information (S22).
  • the line congestion information is repeatedly reported at predetermined intervals in a cell formed by the base station 50.
  • transmission data is generated in the wireless terminals 70A and B (S23). Then, the wireless terminals 70A and 70B determine whether to suspend transmission based on the line congestion information and the priority of the transmission data (S24). For example, when the line is not congested (the degree of congestion of the line is less than a predetermined level), it is determined that the transmission is not suspended. Further, for example, when the line is congested (the degree of congestion of the line is equal to or higher than a predetermined level), the priority of the transmission data is determined. If the priority of the transmission data is relatively high, it is determined that the transmission is not suspended. If the priority of the transmission data is relatively low, it is determined that the transmission is suspended.
  • the wireless terminal 70A determines that the transmission is not suspended because the line is congested and the priority of the transmission data is “high”. Further, the radio terminal 20B determines that the transmission is not suspended because the line is congested and the priority of the transmission data is “low”.
  • the process proceeds to S29, and the wireless terminal 70A transmits a RACH signal. Then, the random access procedure with the base station 50 is executed, and the wireless terminal 70A shifts to the connected state and starts data transmission (S30). On the other hand, when the transmission is suspended (Yes in S24), the data transmission is not started and the process proceeds to S27. As a result, when the line is not congested, access for starting transmission is executed regardless of the characteristics of the transmission data, and data transmission can be started. When the line is congested, transmission data having a high priority is accessed for starting transmission, and transmission data having a relatively low priority is reserved for starting transmission.
  • the base station 50 determines whether or not to cancel the suspension of transmission at the wireless terminal that suspended the transmission (S25). For example, the base station 50 determines whether or not the line is congested. If the base station 50 determines that the line is not congested, the base station 50 determines to cancel the suspension of transmission.
  • the base station 50 transmits the cancellation information via the PCH signal (S26).
  • the wireless terminal 70B performs a PCH signal reception process (S27). Then, the wireless terminal 70B determines whether or not the release information has been received (S28). If the release information has not been received (No in S28), the process returns to S27. Until the determination result in S28 is Yes, the wireless terminal 70B performs PCH signal reception processing at predetermined intervals. As a result, transmission suspension is continued.
  • the wireless terminal 70B releases the suspension of transmission, proceeds to S29, and transmits a RACH signal. Then, a random access procedure with the base station 50 is executed, and the wireless terminal 70B shifts to the connected state and starts data transmission (S30).
  • S30 data transmission
  • the wireless communication system 1 it is possible to efficiently control access from a wireless terminal and improve communication performance.
  • the base station according to the third embodiment is different from the base station 50 according to the second embodiment in operations related to the line congestion determination unit 57, the release information transmission unit 59, and the transmission signal processing unit 60.
  • the line congestion determination unit 57 groups wireless terminals, determines release of transmission suspension for each group, and outputs the release information for each group to the release information transmission unit 59.
  • the group is divided based on, for example, at least one of identification information allocated in advance to the wireless terminal and position information of the wireless terminal.
  • IMSI International Mobile Subscriber Identity
  • IMSI International Mobile Subscriber Identity
  • IMSI is a unique identification number assigned to all mobile phone users and is stored in a SIM card in the mobile phone.
  • wireless terminals whose lower 3 bits match in IMSI are set as the same group.
  • wireless terminals that are relatively close to each other are classified into the same group based on the position information of the wireless terminals.
  • the reception characteristics can be improved by allowing transmission between groups at positions that do not interfere with each other with a directional antenna in cooperation with adjacent base stations.
  • the cancellation information transmission unit 59 includes the group identification information together with the cancellation information in the PCH signal, and outputs it to the transmission signal processing unit 60.
  • the transmission signal processing unit 60 allocates radio resources so that the PCH signal has different timing for each group, and transmits the wireless resource via the transmission antenna 61.
  • Other configurations of the base station according to the third embodiment are the same as the configurations of the base station 50 according to the second embodiment.
  • the hardware configuration of the base station according to the third embodiment is the same as the hardware configuration of the base station 50 according to the second embodiment.
  • the wireless terminal according to the third embodiment is different from the wireless terminal 70A of the second embodiment in operations related to the received signal processing unit 72 and the release information receiving unit 75.
  • the PCH signal received at the timing set in the group including the wireless terminal 70A is output to the release information receiving unit 75.
  • the release information receiving unit 75 performs demodulation processing and decoding processing on the received PCH signal, acquires release information addressed to the group including the own device, and outputs the release information to the hold release determination unit 76.
  • Other configurations of the wireless terminal according to the third embodiment are the same as the configuration of the wireless terminal 70A of the second embodiment.
  • the hardware configuration of the wireless terminal according to the third embodiment is the same as the hardware configuration of the wireless terminal 70A of the second embodiment.
  • FIG. 10 is a sequence diagram for explaining a transmission operation in the radio terminals 70A and 70B in the radio communication system according to the third embodiment.
  • the wireless terminals 70A and 70B are in a standby state and the base station 50 is in a congested line.
  • the transmission data generated in the wireless terminal 70A has a high priority
  • the transmission data generated in the wireless terminal 70B has a low priority.
  • the processing of S41 to S44 and S48 to S50 of the third embodiment is the same as the processing of S21 to S24 and S28 to S30 of the second embodiment.
  • the base station 50 determines whether or not the line is congested (S41).
  • the determination of the congestion of the line is repeatedly executed at a predetermined interval, for example.
  • the base station 50 notifies the wireless terminal 70A, B of the line congestion information (S42).
  • the line congestion information is repeatedly reported at predetermined intervals in a cell formed by the base station 50.
  • transmission data is generated in the wireless terminals 70A and B (S43). Then, the wireless terminals 70A and 70B determine whether or not to hold the transmission based on the line congestion information and the priority of the transmission data (S44). For example, the wireless terminal 70A determines that the transmission is not suspended because the line is congested and the priority of the transmission data is “high”. The wireless terminal 70B determines that the transmission is not suspended because the line is congested and the priority of the transmission data is “low”.
  • the process proceeds to S49, and the wireless terminal 70A transmits a RACH signal. Then, a random access procedure with the base station 50 is executed, and the wireless terminal 70A shifts to a connected state and starts data transmission.
  • the transmission is suspended (the determination result in S44 is Yes)
  • the data transmission is not started and the process proceeds to S47.
  • the line is not congested, access for starting transmission is executed regardless of the characteristics of the transmission data, and data transmission can be started.
  • transmission data having a high priority is accessed for starting transmission, and transmission data having a relatively low priority is reserved for starting transmission.
  • the base station 50 determines, for each group of wireless terminals, whether or not to cancel the transmission suspension by the wireless terminals that have suspended transmission (S45). For example, the base station 50 determines whether or not the line is congested. If the base station 50 determines that the line is not congested, the base station 50 determines to cancel the suspension of transmission. Furthermore, the timing for releasing the hold is set for each group. Moreover, the access time of each wireless terminal included in the group may be set and included in the release information.
  • the base station 50 transmits the cancellation information via the PCH signal according to the timing set for each group (S46).
  • the wireless terminal 70B performs a process of receiving a PCH signal addressed to the group including the own device (S47). Then, the wireless terminal 20B determines whether or not the release information has been received (S48). If the release information has not been received (No in S48), the process returns to S47. Until the determination result in S48 is No, the wireless terminal 70B performs PCH signal reception processing at predetermined intervals. As a result, transmission suspension is continued.
  • the wireless terminal 70B releases the suspension of transmission, proceeds to S49, and transmits a RACH signal. Then, a random access procedure with the base station 50 is executed, and the wireless terminal 70B shifts to the connected state and starts data transmission.
  • a relatively low priority may wait for a certain amount of time
  • the release information is notified for each group, for example, the transmission suspension is released at different timing for each group, so the line is congested compared to the case where the wireless terminal transmission suspension is released all at once. The possibility of doing so can be avoided.
  • the third embodiment it is possible to efficiently control access from a wireless terminal and improve communication performance in a wireless communication system.
  • the base station according to the fourth embodiment is different from the base station 50 according to the second embodiment in operations related to the release information transmission unit 59 and the transmission signal processing unit 60.
  • the release information transmission unit 59 generates a PDCCH order from the control information and outputs it to the transmission signal processing unit 60.
  • PDCCH order is used for uplink synchronization in a connected wireless terminal under the base station 50.
  • PDCCH order includes release information output from the line congestion determination unit 57.
  • the PDCCH order is transmitted with identification information C-RNTI (Radio Network Temporary Identifier) allocated to each wireless terminal under the base station 50 added thereto, for example.
  • the PDCCH order is transmitted using PDCCH as a physical channel.
  • the release information transmission unit 59 outputs the PDCCH order to the transmission signal processing unit 60 and transmits it via the transmission antenna 61.
  • C-RNTI Radio Network Temporary Identifier
  • the base station according to the fourth embodiment is the same as the configurations of the base station 50 according to the second embodiment.
  • the hardware configuration of the base station according to the fourth embodiment is the same as the hardware configuration of the base station 50 according to the second embodiment.
  • the wireless terminal according to the fourth embodiment is different from the wireless terminal 70A of the second embodiment in operations related to the received signal processing unit 72 and the release information receiving unit 75.
  • the received signal processing unit 72 outputs the received PDCCH order to the release information receiving unit 75.
  • the cancellation information receiving unit 75 performs demodulation processing and decoding processing on the received PDCCH order.
  • the release information receiving unit 75 extracts control information from the reception signal subjected to the decoding process.
  • the extracted control information includes, for example, release information for releasing transmission suspension.
  • the release information receiving unit 75 outputs the received control information to the hold release determining unit 76.
  • the PDCCH on which CRC (Cyclic Redundancy Check) mask based on C-RNTI is applied can be received using C-RNTI.
  • Other configurations of the wireless terminal according to the fourth embodiment are the same as the configuration of the wireless terminal 70A of the second embodiment.
  • the hardware configuration of the wireless terminal according to the fourth embodiment is the same as the hardware configuration of the wireless terminal 70A of the second embodiment.
  • FIG. 11 is a sequence diagram for explaining a transmission operation in the radio terminals 70A and 70B in the radio communication system according to the fourth embodiment.
  • the wireless terminals 70A and 70B are in a connected state (Connected state), and a line is congested in the base station 50.
  • the transmission data generated in the wireless terminal 70A has a high priority
  • the transmission data generated in the wireless terminal 70B has a low priority.
  • the base station 50 determines whether or not the line is congested (S61).
  • the determination of the congestion of the line is repeatedly executed at a predetermined interval, for example.
  • the base station 50 notifies the wireless terminal 70A, B of the line congestion information (S62).
  • the line congestion information is repeatedly reported at predetermined intervals in a cell formed by the base station 50.
  • transmission data is generated in the wireless terminals 70A and B (S63). Then, the wireless terminals 70A and 70B determine whether to suspend transmission based on the line congestion information and the priority of the transmission data (S64). For example, when the line is not congested (the degree of congestion of the line is less than a predetermined level), it is determined that the transmission is not suspended. Further, for example, when the line is congested (the degree of congestion of the line is equal to or higher than a predetermined level), the priority of the transmission data is determined. If the priority of the transmission data is relatively high, it is determined that the transmission is not suspended. If the priority of the transmission data is relatively low, it is determined that the transmission is suspended.
  • the wireless terminal 70A determines that the transmission is not suspended because the line is congested and the priority of the transmission data is “high”. Further, the radio terminal 20B determines that the transmission is not suspended because the line is congested and the priority of the transmission data is “low”.
  • the base station 50 determines whether or not to cancel the suspension of transmission at the wireless terminal that suspended the transmission (S65). For example, the base station 50 determines whether or not the line is congested. If the base station 50 determines that the line is not congested, the base station 50 determines to cancel the suspension of transmission.
  • the base station 50 transmits the cancellation information via the PDCCH order (S66).
  • the wireless terminal 70B performs a PDCCH order reception process (S67). Then, the wireless terminal 70B determines whether or not the release information has been received (S68). If the release information has not been received (No in S68), the process returns to S67. Until the determination result in S68 is No, the wireless terminal 70B performs PDCCH order reception processing at predetermined intervals. As a result, transmission suspension is continued.
  • the wireless terminal 70B releases the suspension of transmission, proceeds to S69, and transmits a RACH signal. Then, a random access procedure with the base station 50 is executed, and the wireless terminal 70B shifts to the uplink synchronization state and starts data transmission (S70).
  • S70 data transmission
  • the fourth embodiment it is possible to efficiently control access from a wireless terminal and improve communication performance in a wireless communication system.
  • the base station may group wireless terminals, determine release of transmission suspension for each group, and notify release information. According to this, since the suspension of transmission is released at a different timing for each group, for example, it is possible to avoid the possibility that the line is congested, compared to the case where the suspension of transmission of wireless terminals is released all at once. . In addition, the amount of signaling is reduced as compared with the case where the release information is individually notified.
  • the PDCCH order may be simultaneously notified to the wireless terminals included in the group by applying a CRCTImask using group identification information instead of C-RNTI.
  • the group identification information is notified in advance as broadcast information, for example.
  • RACH signals may be transmitted simultaneously from the wireless terminals included in the group.
  • the access time of each wireless terminal may be set as a parameter in the PDCCH order, and each wireless terminal may randomly select an access slot within the access time to avoid RACH signal collision.
  • the base station may group all the wireless terminals under its control into one group, determine whether to cancel the suspension of transmission to all the wireless terminals, and notify the cancellation information.
  • the release information is transmitted via the PDCCH order, but may be transmitted via the RRC message, for example.
  • the PDSCH containing the RRC message can be received by receiving the PDCCH on which the CRC mask based on the C-RNTI is applied using the C-RNTI.
  • the wireless communication systems of the first to fourth embodiments can be realized as, for example, an LTE system or an LTE-A system.
  • the present invention can also be applied to a wireless communication system using a communication method other than LTE or LTE-A.
  • two wireless terminals are provided.
  • the present invention is not limited to this, and the number of wireless terminals is arbitrary.
  • the first to fourth embodiments can be applied to mobile terminals such as mobile phones, smartphones, and PDAs (Personal Digital Assistants) as wireless terminals.
  • the first to fourth embodiments can be applied to various communication devices that communicate with a base station such as a mobile relay station.
  • first to fourth embodiments can be applied to base stations of various sizes such as macro base stations and femto base stations as base stations.
  • first to fourth embodiments can be applied to various communication devices that communicate with mobile stations such as relay stations.
  • each component of the base station and the radio terminal is not limited to the mode of the first to fourth embodiments, and all or a part thereof can be used for various loads, usage conditions, and the like. Accordingly, it may be configured to be functionally or physically distributed / integrated in an arbitrary unit.
  • the memory may be connected via a network or a cable as an external device of a base station or a wireless terminal.

Abstract

The disclosed technology has been made in view of the above, and has the objective of providing a wireless communication method, wireless communication system, base station and wireless terminal which efficiently control access from wireless terminals and improve communication performance. The wireless communication method comprises notifying a wireless terminal from a base station of information related to the status of a link, and controlling, if transmission data to the base station is generated at the wireless terminal, whether or not to suspend transmission to the base station on the basis of the information related to the status of the link and characteristics of the transmission data.

Description

無線通信方法、無線通信システム、基地局および無線端末Wireless communication method, wireless communication system, base station, and wireless terminal
　本発明は、無線通信方法、無線通信システム、基地局および無線端末に関する。 The present invention relates to a wireless communication method, a wireless communication system, a base station, and a wireless terminal.
　近年、携帯電話システム等の無線通信システムにおいて、無線通信の更なる高速化・大容量化等を図るため、次世代の無線通信技術について議論が行われている。例えば、標準化団体である３ＧＰＰ（3rd Generation Partnership Project）では、ＬＴＥ（Long Term Evolution）と呼ばれる通信規格や、ＬＴＥの無線通信技術をベースとしたＬＴＥ－Ａ（LTE - Advanced）と呼ばれる通信規格が提案されている。 In recent years, next-generation wireless communication technologies have been discussed in order to further increase the speed and capacity of wireless communication in wireless communication systems such as mobile phone systems. For example, 3GPP (3rd Generation Partnership Project), a standardization organization, proposes a communication standard called LTE (Long Term Evolution) and a communication standard called LTE-A (LTE-Advanced) based on LTE wireless communication technology. Has been.
　このような無線通信システムにおいて、例えば、待受け状態にある無線端末で送信データが発生した場合に、ＲＡＣＨ (Random Access Channel)を用いて基地局にアクセスして接続を確立し、データの送信を開始する。また、例えば、接続状態にある無線端末で、新たに送信データが発生した場合に、ＲＡＣＨを用いて基地局にアクセスしたり、予め割り当てられたＰＵＣＣＨ (Physical Uplink Control Channel)を用いて基地局にアクセスしたりして、データの送信を開始する。 In such a wireless communication system, for example, when transmission data is generated in a standby wireless terminal, a connection is established by accessing a base station using RACH (Random Access Channel), and data transmission is started. To do. Also, for example, when new transmission data is generated in a wireless terminal in a connected state, the base station is accessed using the RACH, or the PUCCH (Physical Uplink Control Channel) allocated in advance is used. Or start sending data.
　上述のような無線通信システムにおいて、例えばスマートフォンの普及等に伴い、通信のトラフィック量が急増して回線が混雑することが想定される。この場合、上述のように送信データが発生するたびに無線端末が基地局にアクセスしようすると、回線の混雑のためにアクセスできず、データが送信できずに、アクセスのためのシグナリングが無駄になる恐れがある。また、このシグナリングがさらに他のアクセスを妨げてしまう恐れがある。 In the wireless communication system as described above, for example, with the spread of smartphones, it is assumed that the amount of communication traffic increases rapidly and the line is congested. In this case, if the wireless terminal tries to access the base station every time transmission data is generated as described above, it cannot be accessed due to line congestion, data cannot be transmitted, and signaling for access is wasted. There is a fear. In addition, this signaling may further hinder other accesses.
　開示の技術は、上記に鑑みてなされたものであって、無線通信システムにおいて、無線端末からのアクセスを効率良く制御し、通信性能を向上できる無線通信方法、無線通信システム、基地局および無線端末を提供することを目的とする。 The disclosed technology has been made in view of the above, and in a wireless communication system, a wireless communication method, a wireless communication system, a base station, and a wireless terminal capable of efficiently controlling access from a wireless terminal and improving communication performance The purpose is to provide.
　上述した課題を解決し、目的を達成するために、本件の開示する無線通信方法は、回線の状況に関する情報を基地局から無線端末に通知し、前記無線端末で前記基地局への送信データが発生した際に、前記回線の状況に関する情報と、前記送信データの特性とに基づいて、前記基地局への送信の保留を行うか否かを制御する。 In order to solve the above-described problems and achieve the object, the wireless communication method disclosed in the present application notifies the wireless terminal of information related to the state of the line, and the wireless terminal transmits data to the base station. When the error occurs, it is controlled whether or not to hold the transmission to the base station based on the information on the state of the line and the characteristics of the transmission data.
　本件の開示する無線通信方法の一つの態様によれば、無線通信システムにおいて、無線端末からのアクセスを効率良く制御し、通信性能を向上できるという効果を奏する。 According to one aspect of the wireless communication method disclosed in the present case, it is possible to efficiently control access from a wireless terminal and improve communication performance in a wireless communication system.
図１は、第１実施形態に係る無線通信システムの構成を示す図である。FIG. 1 is a diagram illustrating a configuration of a wireless communication system according to the first embodiment. 図２は、第１実施形態に係る基地局の構成を示す機能ブロック図である。FIG. 2 is a functional block diagram showing the configuration of the base station according to the first embodiment. 図３は、第１実施形態に係る無線端末の構成を示す機能ブロック図である。FIG. 3 is a functional block diagram showing the configuration of the wireless terminal according to the first embodiment. 図４は、第１実施形態に係る基地局のハードウェア構成を示す図である。FIG. 4 is a diagram illustrating a hardware configuration of the base station according to the first embodiment. 図５は、第１実施形態に係る無線端末のハードウェア構成を示す図である。FIG. 5 is a diagram illustrating a hardware configuration of the wireless terminal according to the first embodiment. 図６は、第１実施形態に係る無線通信システムの動作を説明するためのシーケンス図である。FIG. 6 is a sequence diagram for explaining the operation of the wireless communication system according to the first embodiment. 図７は、第２実施形態に係る無線通信システムの基地局の構成を示す機能ブロック図である。FIG. 7 is a functional block diagram showing the configuration of the base station of the wireless communication system according to the second embodiment. 図８は、第２実施形態に係る無線通信システムの無線端末の構成を示す機能ブロック図である。FIG. 8 is a functional block diagram showing a configuration of a wireless terminal of the wireless communication system according to the second embodiment. 図９は、第２実施形態に係る無線通信システムの動作を説明するためのシーケンス図である。FIG. 9 is a sequence diagram for explaining the operation of the radio communication system according to the second embodiment. 図１０は、第３実施形態に係る無線通信システムの動作を説明するためのシーケンス図である。FIG. 10 is a sequence diagram for explaining the operation of the wireless communication system according to the third embodiment. 図１１は、第４実施形態に係る無線通信システムの動作を説明するためのシーケンス図である。FIG. 11 is a sequence diagram for explaining the operation of the wireless communication system according to the fourth embodiment.
　以下に、本件の開示する無線通信方法、無線通信システム、基地局および無線端末の実施形態を、図面を参照しながら説明する。なお、以下の実施形態により本件の開示する無線通信方法、無線通信システム、基地局および無線端末が限定されるものではない。 Hereinafter, embodiments of a wireless communication method, a wireless communication system, a base station, and a wireless terminal disclosed in the present application will be described with reference to the drawings. The wireless communication method, the wireless communication system, the base station, and the wireless terminal disclosed in the present application are not limited to the following embodiments.
［第１実施形態］
　図１は、第１実施形態に係る無線通信システム１の構成を示す。図１に示すように、無線通信システム１は、基地局１０と、無線端末２０Ａ，Ｂとを有する。基地局１０は、セルＣ１０を形成している。無線端末２０Ａ，ＢはセルＣ１０に存在している。 [First Embodiment]
FIG. 1 shows a configuration of a wireless communication system 1 according to the first embodiment. As shown in FIG. 1, the radio communication system 1 includes a base station 10 and radio terminals 20A and 20B. The base station 10 forms a cell C10. The radio terminals 20A and 20B exist in the cell C10.
　基地局１０は、有線接続を介してネットワーク装置３と接続されており、ネットワーク装置３は、有線接続を介してネットワーク２に接続されている。基地局１０は、ネットワーク装置３およびネットワーク２を介して、他の基地局とデータや制御情報を送受信可能に設けられている。 The base station 10 is connected to the network device 3 via a wired connection, and the network device 3 is connected to the network 2 via a wired connection. The base station 10 is provided so as to be able to transmit and receive data and control information to and from other base stations via the network device 3 and the network 2.
　ネットワーク装置３は、例えば通信部と制御部とを備え、これら各構成部分が、一方向または双方向に、信号やデータの入出力が可能なように接続されている。ネットワーク装置３は、例えばゲートウェイにより実現される。ネットワーク装置３のハードウェア構成としては、例えば通信部はインタフェース回路、制御部はプロセッサとメモリとで実現される。 The network device 3 includes, for example, a communication unit and a control unit, and these components are connected so that signals and data can be input and output in one direction or in both directions. The network device 3 is realized by a gateway, for example. As a hardware configuration of the network device 3, for example, the communication unit is realized by an interface circuit, and the control unit is realized by a processor and a memory.
　図２は、基地局１０の構成を示す機能ブロック図である。図２に示すように、基地局１０は、送信部１１と、受信部１２と、制御部１３とを備える。これら各構成部分は、一方向または双方向に、信号やデータの入出力が可能なように接続されている。 FIG. 2 is a functional block diagram showing the configuration of the base station 10. As shown in FIG. 2, the base station 10 includes a transmission unit 11, a reception unit 12, and a control unit 13. Each of these components is connected so that signals and data can be input and output in one direction or in both directions.
　送信部１１は、データ信号や制御信号を、アンテナを介して送信する。送信部１１は、例えば下りのデータチャネルや制御チャネルを介して、下り信号を送信する。下りの物理データチャネルは例えば個別データチャネルＰＤＳＣＨ(Physical Downlink Shared Channel)を含む。また、下りの物理制御チャネルは、個別制御チャネルＰＤＣＣＨ(Physical Downlink Control Channel)を含む。送信する信号は例えば、基地局１０での回線の状況に関する情報や、無線端末２０Ａ，Ｂで送信の保留を解除するための解除情報を含む。例えば、回線の状況に関する情報は、基地局１０が形成するセルＣ１０内へ、報知情報として報知される。また例えば、解除情報は、待受け状態（Idle Mode）の無線端末に対して、ＰＣＨ(Paging Channel)信号を介して通知される。ＰＣＨは、セルＣ１０内に情報を一斉に転送する下りのトランスポートチャネルである。ＰＣＨ信号は、例えば無線端末へ呼の着信があった場合に、当該無線端末を呼び出すために使用される。また例えば解除情報は、接続状態（Connected Mode）の無線端末に対して、PDCCH order又はRRC (Radio Resource Control) messageを介して通知される。PDCCH orderは、接続状態の無線端末に個別制御チャネルを介して送信されるＬ１／Ｌ２制御信号で、例えば無線端末が上り同期確立を実行するために使用される。また、RRC messageは、接続状態の無線端末に個別データチャネルを介して送信される上位レイヤ制御信号である。 The transmission unit 11 transmits a data signal and a control signal via an antenna. The transmitter 11 transmits a downlink signal via, for example, a downlink data channel or a control channel. The downlink physical data channel includes, for example, a dedicated data channel PDSCH (Physical Downlink Shared Channel). The downlink physical control channel includes a dedicated control channel PDCCH (PhysicalPhysDownlink Control Channel). The signal to be transmitted includes, for example, information regarding the line status at the base station 10 and release information for releasing the suspension of transmission at the radio terminals 20A and 20B. For example, information related to the line status is broadcast as broadcast information into the cell C10 formed by the base station 10. Further, for example, the release information is notified to a wireless terminal in a standby state (Idle Mode) via a PCH (Paging Channel) signal. The PCH is a downlink transport channel that transfers information in the cell C10 all at once. The PCH signal is used, for example, to call a wireless terminal when a call arrives at the wireless terminal. Also, for example, the release information is notified to a wireless terminal in a connected state (Connected Mode) via PDCCH order or RRC (Radio Resource Control) message. PDCCH order is an L1 / L2 control signal transmitted to the connected wireless terminal via the dedicated control channel, and is used for the wireless terminal to establish uplink synchronization, for example. The RRC message is an upper layer control signal transmitted via a dedicated data channel to a connected wireless terminal.
　受信部１２は、無線端末２０Ａ，Ｂから送信されたデータ信号や制御信号を、アンテナを介して受信する。受信部１２は、例えば上りのデータチャネルや制御チャネルを介して、上り信号を受信する。上りの物理データチャネルは例えば個別データチャネルＰＵＳＣＨ（Physical Uplink Shared Channel）を含む。また、上りの物理制御チャネルは、個別制御チャネルＰＵＣＣＨを含む。受信する信号は例えば、無線端末２０Ａ，Ｂから送信されるＲＡＣＨ信号を含む。ＲＡＣＨは、無線端末がランダムアクセスを行うための信号を送信するためのトランスポートチャネルである。ＲＡＣＨ信号は、ランダムアクセス手順で無線端末から送信される信号である。基地局１０は、ＲＡＣＨ信号を受信して情報のやり取りを行うことで、無線端末を認識し、自局に接続している無線端末の情報を管理する。なお、アンテナは送信と受信で共通でもよい。 The receiving unit 12 receives data signals and control signals transmitted from the wireless terminals 20A and 20B via an antenna. The receiving unit 12 receives an uplink signal via, for example, an uplink data channel or a control channel. The uplink physical data channel includes, for example, a dedicated data channel PUSCH (Physical Uplink Shared Channel). The uplink physical control channel includes a dedicated control channel PUCCH. The received signal includes, for example, a RACH signal transmitted from the radio terminals 20A and 20B. RACH is a transport channel for transmitting a signal for wireless terminals to perform random access. The RACH signal is a signal transmitted from a wireless terminal in a random access procedure. The base station 10 receives the RACH signal and exchanges information, thereby recognizing the wireless terminal and managing information on the wireless terminal connected to the own station. The antenna may be common for transmission and reception.
　制御部１３は、有線接続あるいは無線接続を介して、ネットワーク装置３や他の基地局からデータや制御情報を取得する。制御部１３は、送信するデータや制御情報を送信部１１に出力する。制御部１３は、受信されるデータや制御情報を受信部１２から入力する。 The control unit 13 acquires data and control information from the network device 3 and other base stations via a wired connection or a wireless connection. The control unit 13 outputs data to be transmitted and control information to the transmission unit 11. The control unit 13 inputs received data and control information from the reception unit 12.
　制御部１３は、基地局１０での回線の状況を判定し、回線の状況に関する情報を無線端末へ通知させる。回線の状況に関する情報としては、例えば回線が混雑しているか否かを示す回線混雑情報が挙げられる。回線混雑情報は、例えば回線の混雑度を含む。回線の混雑度は、「回線が混雑している」「回線が混雑していない」の２段階に設定される。回線の混雑度は、２段階に限らず、任意に設定可能である。回線の混雑度は例えば、基地局１０が形成するセルＣ１０内の上り通信中の無線端末の数、下り通信中の無線端末の数、セルＣ１０内の無線端末から基地局１０へ送信すべき上り送信データ量、および基地局１０からセルＣ１０内の無線端末へ送信すべき下り送信データ量、の少なくともいずれかに基づいて、判断される。 The control unit 13 determines the line status at the base station 10 and notifies the wireless terminal of information related to the line status. Examples of the information regarding the line status include line congestion information indicating whether or not the line is congested. The line congestion information includes, for example, the line congestion level. The degree of line congestion is set in two stages: “line is congested” and “line is not congested”. The congestion level of the line is not limited to two stages, and can be set arbitrarily. The congestion level of the line is, for example, the number of wireless terminals in uplink communication in the cell C10 formed by the base station 10, the number of wireless terminals in downlink communication, and the uplink to be transmitted from the wireless terminals in the cell C10 to the base station 10 This is determined based on at least one of the transmission data amount and the downlink transmission data amount to be transmitted from the base station 10 to the radio terminal in the cell C10.
　また、制御部１３は、データ送信を保留している無線端末の保留を解除するか否かを判定し、解除情報を無線端末１０Ａ，Ｂへ送信させる。保留解除の判定は、例えば回線が混雑していることを示す情報を通知している場合に実行される。また、保留を解除するか否かは、例えば基地局１０の回線の状況に関する情報に基づいて行われる。制御部１３は、例えば回線が混雑していないと判定された場合に、保留を解除すると判定する。なお、保留解除の判定条件と、回線混雑の判定条件とは、同じ条件としても、異なる条件としてもよい。 Further, the control unit 13 determines whether or not to cancel the hold of the wireless terminal holding data transmission, and transmits the release information to the wireless terminals 10A and 10B. The determination of the release of the hold is executed, for example, when notifying information indicating that the line is congested. Whether or not to cancel the hold is determined based on, for example, information related to the line status of the base station 10. For example, when it is determined that the line is not congested, the control unit 13 determines to cancel the hold. Note that the hold cancellation determination condition and the line congestion determination condition may be the same condition or different conditions.
　図３は、無線端末２０Ａの構成を示す機能ブロック図である。図３に示すように、無線端末２０Ａは、送信部２１と、受信部２２と、制御部２３とを備える。これら各構成部分は、一方向又は双方向に、信号やデータの入出力が可能なように接続されている。なお、無線端末２０Ｂの機能的構成およびハードウェア構成は、無線端末２０Ａの機能的構成及びハードウェア構成と同様である。 FIG. 3 is a functional block diagram showing the configuration of the wireless terminal 20A. As illustrated in FIG. 3, the radio terminal 20 </ b> A includes a transmission unit 21, a reception unit 22, and a control unit 23. Each of these components is connected so that signals and data can be input and output in one direction or in both directions. The functional configuration and hardware configuration of the wireless terminal 20B are the same as the functional configuration and hardware configuration of the wireless terminal 20A.
　送信部２１は、データ信号や制御信号を、アンテナを介して送信する。送信部２１は、例えば上りのデータチャネルや制御チャネルを介して、上り信号を送信する。送信する信号は例えば、ＲＡＣＨ信号を含む。無線端末２０Ａは、ＲＡＣＨ信号を送信し、ランダムアクセス手順により、基地局１０と接続確立のための情報のやり取りを行う。 The transmission unit 21 transmits a data signal and a control signal via an antenna. The transmission unit 21 transmits an uplink signal via, for example, an uplink data channel or a control channel. The signal to be transmitted includes, for example, a RACH signal. The radio terminal 20A transmits a RACH signal and exchanges information for establishing a connection with the base station 10 according to a random access procedure.
　受信部２２は、基地局から送信されたデータ信号や制御信号を、アンテナを介して受信する。受信する信号は例えば、回線の状況に関する情報や、送信の保留を解除するための解除情報を含む。なお、アンテナは送信と受信で共通でもよい。 The receiving unit 22 receives data signals and control signals transmitted from the base station via an antenna. The received signal includes, for example, information on the line status and release information for releasing the transmission suspension. The antenna may be common for transmission and reception.
　制御部２３は、送信するデータや制御情報を送信部２１に出力する。また、制御部２３は、受信部２２から受信されるデータや制御情報を入力する。 The control unit 23 outputs data to be transmitted and control information to the transmission unit 21. In addition, the control unit 23 inputs data and control information received from the receiving unit 22.
　制御部２３は、基地局１０への送信データが発生した際に、受信した回線の状況に関する情報と、送信データの特性とに基づいて、基地局１０への送信の保留を行うか否かを判断する。また、制御部２３は、受信した解除情報に応じて、送信の保留を解除し、基地局１０への送信データの送信を開始する。制御部２３は、無線端末２０Ａが待受け状態にある場合や接続状態にある場合、送信データが発生した際に、送信の保留を行うか否かを判断する。送信データの特性は、例えば送信データの優先度を含む。送信データの優先度は、例えば無線端末２０Ａに設定されるサービスの種類、送信データを使用するアプリケーションの種類、送信データの論理チャネル番号、および送信データの許容遅延時間の少なくともいずれかに基づいて判断される。 When the transmission data to the base station 10 is generated, the control unit 23 determines whether or not to hold the transmission to the base station 10 based on the received information on the status of the line and the characteristics of the transmission data. to decide. In addition, the control unit 23 releases the suspension of transmission according to the received release information, and starts transmission of transmission data to the base station 10. When the wireless terminal 20A is in a standby state or in a connected state, the control unit 23 determines whether or not to hold transmission when transmission data is generated. The characteristics of the transmission data include, for example, the priority of the transmission data. The priority of the transmission data is determined based on, for example, at least one of the type of service set in the radio terminal 20A, the type of application using the transmission data, the logical channel number of the transmission data, and the allowable delay time of the transmission data. Is done.
　例えば、制御部２３は、回線の混雑度が所定レベル未満（回線が混雑していない）の場合、送信の保留を行わないと判断し、ＲＡＣＨ信号を送信して接続を確立して、送信データの送信を開始する。また、例えば、制御部２３は、回線の混雑度が所定レベル以上（回線が混雑している）で、かつ送信データの優先度が所定レベル以上の場合、送信の保留を行わないと判断し、ＲＡＣＨ信号を送信して接続を確立して、送信データの送信を開始する。一方、制御部２３は、回線の混雑度が所定レベル以上で、かつ送信データの優先度が所定レベル未満の場合、送信の保留を行うと判断し、ＲＡＣＨ信号を送信せず、送信データの送信を開始しない。 For example, when the congestion level of the line is less than a predetermined level (the line is not congested), the control unit 23 determines that the transmission is not suspended, transmits a RACH signal, establishes a connection, and transmits the transmission data. Start sending. For example, the control unit 23 determines that the transmission is not suspended when the congestion level of the line is equal to or higher than a predetermined level (the line is congested) and the priority of the transmission data is equal to or higher than the predetermined level. A RACH signal is transmitted to establish a connection, and transmission of transmission data is started. On the other hand, if the congestion level of the line is equal to or higher than the predetermined level and the priority of the transmission data is lower than the predetermined level, the control unit 23 determines that the transmission is suspended, does not transmit the RACH signal, and transmits the transmission data. Do not start.
　また、制御部２３は、送信の保留を行っている場合に、解除情報を受信すると、送信の保留を解除して、ＲＡＣＨ信号を送信して接続を確立して、保留していた送信データの送信を開始する。 Further, when receiving the release information when the transmission is suspended, the control unit 23 releases the suspension of transmission, transmits a RACH signal, establishes a connection, and transmits the suspended transmission data. Start sending.
　図４は、基地局１０のハードウェア構成を示す図である。図４に示すように、基地局１０は、ハードウェアの構成要素として、例えばアンテナ３１を備えるＲＦ（Radio　Frequency）回路３２と、ＣＰＵ（Central Processing Unit）３３と、ＤＳＰ（Digital　Signal　Processor）３４と、メモリ３５と、ネットワークＩＦ（Interface）３６とを有する。ＣＰＵは、スイッチ等のネットワークＩＦ３６を介して各種信号やデータの入出力が可能なように接続されている。メモリ３５は、例えばＳＤＲＡＭ（Synchronous　Dynamic　Random　Access　Memory）等のＲＡＭ（Random　Access　Memory）、ＲＯＭ（Read　Only　Memory)、及びフラッシュメモリの少なくともいずれかを含み、プログラムや制御情報やデータを格納する。送信部１１及び受信部１２は、例えばアンテナ３１およびＲＦ回路３２により実現される。制御部１３は、例えばＣＰＵ３３等の集積回路あるいはＤＳＰ３４等の集積回路により実現される。 FIG. 4 is a diagram illustrating a hardware configuration of the base station 10. As shown in FIG. 4, the base station 10 includes, as hardware components, an RF (Radio Frequency) circuit 32 including an antenna 31, a CPU (Central Processing Unit) 33, a DSP (Digital Signal Processor) 34, and the like. , A memory 35 and a network IF (Interface) 36. The CPU is connected via a network IF 36 such as a switch so that various signals and data can be input and output. The memory 35 includes at least one of RAM (Random Access Memory) such as SDRAM (Synchronous Dynamic Random Access Memory), ROM (Read Only Memory), and flash memory, and stores programs, control information, and data. The transmitter 11 and the receiver 12 are realized by an antenna 31 and an RF circuit 32, for example. The control unit 13 is realized by, for example, an integrated circuit such as the CPU 33 or an integrated circuit such as the DSP 34.
　図５は、無線端末２０Ａのハードウェア構成を示す図である。図５に示すように、無線端末２０Ａは、ハードウェアの構成要素として、例えばアンテナ４１を備えるＲＦ回路４２と、ＣＰＵ４３と、メモリ４４とを有する。さらに、無線端末２０Ａは、ＣＰＵ４３に接続されるＬＣＤ（Liquid　Crystal　Display）等の表示装置を有してもよい。メモリ４４は、例えばＳＤＲＡＭ等のＲＡＭ、ＲＯＭ、及びフラッシュメモリの少なくともいずれかを含み、プログラムや制御情報やデータを格納する。送信部２１及び受信部２２は、例えばアンテナ４１およびＲＦ回路４２により実現される。制御部２３は、例えばＣＰＵ４３等の集積回路により実現される。 FIG. 5 is a diagram illustrating a hardware configuration of the wireless terminal 20A. As illustrated in FIG. 5, the radio terminal 20 </ b> A includes, as hardware components, for example, an RF circuit 42 including an antenna 41, a CPU 43, and a memory 44. Furthermore, the radio terminal 20 </ b> A may include a display device such as an LCD (Liquid Crystal Display) connected to the CPU 43. The memory 44 includes at least one of RAM such as SDRAM, ROM, and flash memory, for example, and stores programs, control information, and data. The transmitter 21 and the receiver 22 are realized by an antenna 41 and an RF circuit 42, for example. The control unit 23 is realized by an integrated circuit such as the CPU 43, for example.
　次に、第１実施形態における無線通信システム１の動作を説明する。図６は、無線通信システム１で、無線端末２０Ａ，Ｂでのデータの送信動作を説明するためのシーケンス図である。 Next, the operation of the wireless communication system 1 in the first embodiment will be described. FIG. 6 is a sequence diagram for explaining a data transmission operation in the radio terminals 20A and 20B in the radio communication system 1.
　ここで、比較例として、送信データが発生した無線端末で、そのつど基地局１０にアクセスする場合を考える。例えば、Idle Modeにある無線端末で、送信データが発生すると、ＲＡＣＨ信号を基地局１０に送信してランダムアクセス手順を実行し、Connected Modeに遷移して接続を確立し、送信データの送信を開始する。また、Connected Modeにある無線端末で、新たな送信データが発生すると、ＲＡＣＨ信号を基地局１０に送信してランダムアクセス手順を実行し、上り同期を確立し、送信データの送信を開始する。または、Connected Modeにある無線端末で、新たな送信データが発生すると、予め当該無線端末に割り当てられたＰＵＣＣＨを用いて基地局にアクセスし、送信データの送信を開始する。この場合、いずれにしても、常に基地局１０にアクセスする動作となっている。 Here, as a comparative example, consider a case where a wireless terminal in which transmission data is generated accesses the base station 10 each time. For example, when transmission data is generated in a wireless terminal in Idle Mode, a RACH signal is transmitted to the base station 10 to execute a random access procedure, a transition is made to Connected 接 続 Mode, a connection is established, and transmission of transmission data is started To do. Further, when new transmission data is generated in the wireless terminal in the Connected Mode, the RACH signal is transmitted to the base station 10 to execute a random access procedure, uplink synchronization is established, and transmission of transmission data is started. Alternatively, when new transmission data is generated in a wireless terminal in Connected Mode, the base station is accessed using the PUCCH assigned to the wireless terminal in advance, and transmission of transmission data is started. In this case, in any case, the operation always accesses the base station 10.
　このとき、基地局１０での回線の混雑度が比較的低い場合、無線端末が基地局にアクセスでき、データが送信できると考えられる。しかし、基地局１０での回線の混雑度が比較的高い場合、回線の混雑のため基地局１０にアクセスできず、データが送信できない可能性がある。この場合、アクセスのためのシグナリングが無駄になる恐れや、このシグナリングにより他のアクセスが妨げられる恐れがある。 At this time, if the line congestion at the base station 10 is relatively low, it is considered that the wireless terminal can access the base station and transmit data. However, when the line congestion level at the base station 10 is relatively high, the base station 10 cannot be accessed due to the line congestion, and data may not be transmitted. In this case, signaling for access may be wasted, or other access may be hindered by this signaling.
　一方、回線の状況は、時間的に変化するものであり、混雑度が比較的高い時間と、混雑度が比較的低い時間とが混在すると考えられる。また、送信データには多様な特性が想定される。例えば、送信データを使用するアプリケーションの種類によっては、即時性が求められる場合と、ある程度 待機してもよい場合がある。 On the other hand, the state of the line changes with time, and it is considered that a time when the degree of congestion is relatively high and a time when the degree of congestion is relatively low are mixed. Various characteristics are assumed for the transmission data. For example, depending on the type of application that uses the transmission data, there may be a case where immediacy is required or a certain amount of waiting.
　そこで、第１実施形態では、以下のように無線端末からのデータ送信動作が行われる。以下の説明では、前提として、無線端末２０Ａ，Ｂは、待受け状態又は接続状態にあり、また、基地局１０で回線が混雑している状態にある。また、無線端末２０Ａで発生する送信データは、優先度が比較的高く、無線端末２０Ｂで発生する送信データは、優先度が比較的低いものとする。 Therefore, in the first embodiment, the data transmission operation from the wireless terminal is performed as follows. In the following description, as a premise, the wireless terminals 20A and 20B are in a standby state or a connected state, and a line is congested in the base station 10. Further, it is assumed that transmission data generated in the radio terminal 20A has a relatively high priority, and transmission data generated in the radio terminal 20B has a relatively low priority.
　図６に示すように、基地局１０は、回線の状況を判定する（Ｓ１）。基地局１０は、例えば回線が混雑しているか否かを判定する。回線の状況の判定は、例えば所定間隔で繰返し実行される。 As shown in FIG. 6, the base station 10 determines the line status (S1). For example, the base station 10 determines whether or not the line is congested. The determination of the line status is repeatedly executed, for example, at predetermined intervals.
　また、基地局１０は、回線の状況に関する情報を、無線端末に通知する（Ｓ２）。基地局１０は、例えば回線が混雑しているか否かを示す回線混雑情報を通知する。回線の状況に関する情報は、例えばセルＣ１０内に所定間隔で繰返し報知される。 Also, the base station 10 notifies the wireless terminal of information related to the line status (S2). For example, the base station 10 notifies line congestion information indicating whether or not the line is congested. Information regarding the line status is repeatedly reported at predetermined intervals in the cell C10, for example.
　次に、無線端末２０Ａ，Ｂで、送信データが発生する（Ｓ３）。そして、無線端末２０Ａ，Ｂは、回線の状況に関する情報と、送信データの特性とに基づいて、送信を保留するか否かを判断する（Ｓ４）。例えば、回線が混雑していない場合、送信を保留しないと判断される。また例えば、回線が混雑している場合で、かつ送信データの優先度が比較的高い場合、送信を保留しないと判断される。また例えば、回線が混雑している場合で、かつ送信データの優先度が比較的低い場合、送信を保留すると判断される。 Next, transmission data is generated in the wireless terminals 20A and 20B (S3). Then, the wireless terminals 20A and 20B determine whether or not to hold the transmission based on the information on the line status and the characteristics of the transmission data (S4). For example, when the line is not congested, it is determined that transmission is not suspended. For example, when the line is congested and the priority of the transmission data is relatively high, it is determined that the transmission is not suspended. For example, when the line is congested and the priority of the transmission data is relatively low, it is determined that the transmission is suspended.
　具体的には、無線端末２０Ａは、回線が混雑していて、送信データの優先度が比較的高いので、送信を保留しないと判断する。また、無線端末２０Ｂは、回線が混雑していて、送信データの優先度が比較的低いので、送信を保留しないと判断する。 Specifically, the radio terminal 20A determines that transmission is not suspended because the line is congested and the priority of transmission data is relatively high. Further, the radio terminal 20B determines that the transmission is not suspended because the line is congested and the priority of the transmission data is relatively low.
　送信を保留しない場合（Ｓ４の判断結果がＮｏ）、Ｓ９に進み、無線端末２０Ａはそのままデータの送信を開始する。一方、送信を保留する場合（Ｓ４の判断結果がＹｅｓ）、データの送信は開始されず、Ｓ７に進む。これにより、回線が混雑していない場合は、送信データの特性によらず、送信開始のためのアクセスが実行され、データの送信を開始できる。また、回線が混雑している場合は、優先度が高い送信データは送信開始のためのアクセスが実行され、優先度が比較的低い送信データは送信開始のためのアクセスが保留される。これにより、優先度が比較的低い送信データのためのアクセスが、混雑を助長し他のアクセスを妨げることがなくなり、優先度が比較的高い送信データのアクセスが成功する可能性が高まる。よって、優先度が比較的高い送信データ（即時性が求められるデータ）の送信を開始できると共に、アクセスできずにシグナリングが無駄になることを回避できる。 When the transmission is not suspended (No in S4), the process proceeds to S9, and the wireless terminal 20A starts transmitting data as it is. On the other hand, when the transmission is suspended (Yes in S4), the data transmission is not started and the process proceeds to S7. As a result, when the line is not congested, access for starting transmission is executed regardless of the characteristics of the transmission data, and data transmission can be started. When the line is congested, transmission data having a high priority is accessed for starting transmission, and transmission data having a relatively low priority is reserved for starting transmission. As a result, access for transmission data with a relatively low priority does not promote congestion and prevent other accesses, and the possibility of successful access of transmission data with a relatively high priority increases. Therefore, transmission of transmission data having relatively high priority (data that requires immediacy) can be started, and it is possible to avoid signaling being wasted due to inaccessibility.
　次に、基地局１０は、送信を保留した無線端末で、送信の保留を解除するか否かを判定する（Ｓ５）。例えば、基地局１０は、回線が混雑しているか否かを判定し、回線が混雑していないと判定した場合、送信の保留を解除すると判定する。 Next, the base station 10 determines whether or not to cancel the suspension of transmission at the wireless terminal that suspended the transmission (S5). For example, the base station 10 determines whether or not the line is congested. If the base station 10 determines that the line is not congested, the base station 10 determines to cancel the transmission suspension.
　次に、基地局１０は、送信の保留を解除すると判定された場合に、解除情報を送信する（Ｓ６）。 Next, when it is determined that the transmission suspension is canceled, the base station 10 transmits the cancellation information (S6).
　Ｓ４の判断結果がＹｅｓで、Ｓ７に進んだ場合、無線端末２０Ｂは、解除情報の受信処理を行う（Ｓ７）。そして、無線端末２０Ｂは、解除情報を受信済みか否か判定する（Ｓ８）。解除情報が受信済みでない場合（Ｓ８の判断結果がＮｏ）、Ｓ７に戻る。Ｓ８の判断結果がＹｅｓとなるまで、無線端末２０Ｂは、解除情報の受信処理を所定間隔で行う。これにより、送信の保留が継続される。 When the determination result in S4 is Yes and the process proceeds to S7, the radio terminal 20B performs a release information reception process (S7). Then, the wireless terminal 20B determines whether or not the release information has been received (S8). If the release information has not been received (No in S8), the process returns to S7. Until the determination result in S8 is Yes, the radio terminal 20B performs the release information reception process at predetermined intervals. As a result, transmission suspension is continued.
　一方、解除情報を受信済みの場合（Ｓ８の判断結果がＹｅｓ）、無線端末２０Ｂは、送信の保留を解除し、Ｓ９に進み、データの送信を開始する。これにより、例えば回線が混雑していない状態になると、送信が保留されていた、優先度が比較的低い送信データの送信開始のためのアクセスが実行される。よって、優先度が比較的低い（ある程度 待機してもよい）送信データの送信を開始できると共に、アクセスできずにシグナリングが無駄になることを回避できる。したがって、即時性が求められる送信データと、ある程度 待機してもよい送信データとを、アクセスできずにシグナリングが無駄になることを回避しつつ、適切なタイミングで送信開始できる。このように、上述の処理によれば、回線状況と送信データの特性とを考慮して、回線の均質化を図ることができる。 On the other hand, when the release information has been received (the determination result in S8 is Yes), the wireless terminal 20B releases the suspension of transmission, proceeds to S9, and starts data transmission. As a result, for example, when the line is not congested, access for starting transmission of transmission data having a relatively low priority that has been suspended is executed. Therefore, transmission of transmission data having a relatively low priority (may wait for a certain amount of time) can be started, and it is possible to avoid wasteful signaling due to inaccessibility. Therefore, transmission of transmission data that requires immediateness and transmission data that may wait for a certain amount of time can be started at an appropriate timing while avoiding the loss of signaling due to inaccessibility. Thus, according to the above-described processing, it is possible to homogenize the lines in consideration of the line status and the characteristics of the transmission data.
　以上により、第１実施形態によれば、無線通信システム１において、無線端末からのアクセスを効率良く制御し、通信性能を向上できる。 As described above, according to the first embodiment, it is possible to efficiently control access from a wireless terminal and improve communication performance in the wireless communication system 1.
　なお、無線通信システム１で、解除情報は、基地局１０の配下の無線端末全てに一斉に通知されてもよく、無線端末毎に通知されてもよい。また、無線端末ごとに、保留の解除後のアクセス時間を設定し、解除情報に含めて通知してもよい。 In the wireless communication system 1, the release information may be notified to all the wireless terminals under the base station 10 or may be notified for each wireless terminal. In addition, for each wireless terminal, an access time after release of the hold may be set and notified by being included in the release information.
　また、無線通信システム１で、基地局１０は、無線端末２０Ａ，Ｂをグループ化し、グループ毎に送信の保留の解除を判定し、解除情報を通知してもよい。これによれば、例えばグループ毎に異なるタイミングで送信の保留が解除されるので、一斉に無線端末の送信の保留が解除される場合に比べて、回線が輻輳する可能性を回避することができる。この場合、例えば、解除情報とグループ識別情報とが基地局１０から無線端末２０Ａ，Ｂに通知される。グループ識別情報は、グループに含まれる無線端末を識別するための情報である。無線端末２０Ａ，Ｂは、グループ識別情報に基づいて、自装置が含まれるグループ宛の解除情報を取得し、送信の保留を解除し、データの送信を開始する。 Further, in the wireless communication system 1, the base station 10 may group the wireless terminals 20A and 20B, determine release of transmission suspension for each group, and notify the release information. According to this, since the suspension of transmission is released at a different timing for each group, for example, it is possible to avoid the possibility that the line is congested, compared to the case where the suspension of transmission of wireless terminals is released all at once. . In this case, for example, the release information and the group identification information are notified from the base station 10 to the wireless terminals 20A and 20B. The group identification information is information for identifying wireless terminals included in the group. Based on the group identification information, the wireless terminals 20A and 20B acquire release information addressed to the group including the device itself, release the transmission suspension, and start data transmission.
　このとき例えば、基地局１０は、グループ毎に異なるタイミングで解除情報を送信し、無線端末２０Ａ,Ｂは、自装置が含まれるグループ宛てのタイミングで解除情報を受信することで、自装置が含まれるグループ宛ての解除情報を取得してもよい。この場合、グループ宛てのタイミング情報が予め通知される。また例えば、グループ識別情報を報知情報等で予め通知し、基地局１０は、グループ識別情報を用いて解除情報をマスク処理して通知してもよい。この場合、無線端末２０Ａ，Ｂは、グループ識別情報を用いて解除情報が含まれうる信号を処理することで、自装置が含まれるグループ宛の解除情報を取得することができる。 At this time, for example, the base station 10 transmits the release information at a different timing for each group, and the radio terminals 20A and 20B include the own device by receiving the release information at the timing addressed to the group including the own device. Release information addressed to a group may be acquired. In this case, timing information addressed to the group is notified in advance. Further, for example, the group identification information may be notified in advance by broadcast information or the like, and the base station 10 may notify the cancellation information using the group identification information after masking. In this case, the radio terminals 20A and 20B can acquire the release information addressed to the group including the own device by processing a signal that can include the release information using the group identification information.
［第２実施形態］
　第２実施形態に係る無線通信システムは、基地局５０（後述の図７に示す）と、無線端末７０Ａ，Ｂ（後述の図８に示す）とを有する。第２実施形態に係る無線通信システムの全体的構成は、図１に示す無線通信システム１と同様である。無線通信システムの基地局５０、無線端末７０Ａ，Ｂ以外に関する部分は、同じ符号を付して説明を省略する。 [Second Embodiment]
The wireless communication system according to the second embodiment includes a base station 50 (shown in FIG. 7 described later) and wireless terminals 70A and B (shown in FIG. 8 described later). The overall configuration of the wireless communication system according to the second embodiment is the same as that of the wireless communication system 1 shown in FIG. Portions other than the base station 50 and the wireless terminals 70A and B of the wireless communication system are denoted by the same reference numerals and description thereof is omitted.
　無線通信システムにおいて、無線端末７０Ａ，Ｂは、基地局５０が形成するセルに存在している。基地局５０は、有線接続を介してネットワーク装置３と接続されており、ネットワーク装置３は、有線接続を介してネットワーク２に接続されている。基地局５０は、ネットワーク装置３およびネットワーク２を介して、他の基地局とデータや制御情報を送受信可能に設けられている。 In the wireless communication system, the wireless terminals 70A and 70B exist in a cell formed by the base station 50. The base station 50 is connected to the network device 3 via a wired connection, and the network device 3 is connected to the network 2 via a wired connection. The base station 50 is provided so as to be able to transmit and receive data and control information to and from other base stations via the network device 3 and the network 2.
　図７は、基地局５０の構成を示す機能ブロック図である。図７に示すように、基地局５０は、受信アンテナ５１と、受信信号処理部５２と、データ受信部５３と、データ転送部５４と、ＲＡＣＨ受信部５５と、回線確立処理部５６とを有する。また、基地局５０は、回線混雑判定部５７と、データ送信部５８と、解除情報送信部５９と、送信信号処理部６０と、送信アンテナ６１とを有する。これら各構成部分は、一方向または双方向に、信号やデータの入出力が可能なように接続されている。 FIG. 7 is a functional block diagram showing the configuration of the base station 50. As shown in FIG. 7, the base station 50 includes a reception antenna 51, a reception signal processing unit 52, a data reception unit 53, a data transfer unit 54, a RACH reception unit 55, and a line establishment processing unit 56. . The base station 50 includes a line congestion determination unit 57, a data transmission unit 58, a release information transmission unit 59, a transmission signal processing unit 60, and a transmission antenna 61. Each of these components is connected so that signals and data can be input and output in one direction or in both directions.
　受信アンテナ５１は、無線信号を受信して、受信信号処理部５２に出力する。なお、基地局５０は、受信アンテナを複数備えてもよい。また、基地局５０は、アンテナを送信と受信とで共用し、アンテナ共用器により切り替えて使用してもよい。 The receiving antenna 51 receives a radio signal and outputs it to the received signal processing unit 52. Note that the base station 50 may include a plurality of receiving antennas. Further, the base station 50 may share an antenna for transmission and reception, and switch between using an antenna duplexer.
　受信アンテナ５１は、例えば上りのデータチャネルや制御チャネルを介して、上り信号を受信する。信号を受信する物理チャネルは例えば、ＰＲＡＣＨ（Physical Random Access Channel）や、ＰＵＳＣＨやＰＵＣＣＨを含む。上り信号は例えば、ＲＡＣＨ信号や、リファレンス信号や、制御信号や、データ信号を含む。 The receiving antenna 51 receives an upstream signal via, for example, an upstream data channel or a control channel. Physical channels that receive signals include, for example, PRACH (PhysicalPhysRandom Access Channel), PUSCH, and PUCCH. The uplink signal includes, for example, a RACH signal, a reference signal, a control signal, and a data signal.
　受信信号処理部５２は、受信信号に、Ａ／Ｄ（Analog to Digital）変換等の無線処理や、ＦＦＴ処理等のデジタル信号処理を行う。受信信号処理部５２は、データ受信部５３に、受信されたデータ信号や、制御信号や、リファレンス信号を出力する。また、受信信号処理部５２は、ＲＡＣＨ受信部５５に、受信されたＲＡＣＨ信号を出力する。 The reception signal processing unit 52 performs wireless processing such as A / D (Analog-to-Digital) conversion and digital signal processing such as FFT processing on the reception signal. The reception signal processing unit 52 outputs the received data signal, control signal, and reference signal to the data reception unit 53. The reception signal processing unit 52 outputs the received RACH signal to the RACH reception unit 55.
　データ受信部５３は、受信されたデータ信号や制御信号について、復調処理や復号処理を行う。データ受信部５３は例えば、予め通知される或いは格納される制御情報と、復調処理のためのリファレンス信号とに基づいて、復調処理を行う。また、データ受信部５３は、予め通知される或いは格納される制御情報と、チャネル推定のためのリファレンス信号とから推定されるチャネル推定値とに基づいて、復調処理された信号の復号処理を行う。 The data receiving unit 53 performs demodulation processing and decoding processing on the received data signal and control signal. For example, the data receiving unit 53 performs demodulation processing based on control information notified or stored in advance and a reference signal for demodulation processing. Further, the data receiving unit 53 performs a decoding process on the demodulated signal based on the control information notified or stored in advance and the channel estimation value estimated from the reference signal for channel estimation. .
　データ転送部５４は、復号処理された信号のリオーダリング処理等を行い、取得される受信データをネットワーク装置３に転送する。また、データ転送部５４は、受信信号から取得される受信品質や、制御情報等を基地局５０の各部に出力する。 The data transfer unit 54 performs a reordering process or the like of the decoded signal, and transfers the acquired received data to the network device 3. In addition, the data transfer unit 54 outputs reception quality acquired from the received signal, control information, and the like to each unit of the base station 50.
　ＲＡＣＨ受信部５５は、ＲＡＣＨ信号からＲＡＣＨプリアンブルを取得し、回線確立処理部５６に出力する。ＲＡＣＨ信号は、ランダムアクセス手順で無線端末７０Ａ，Ｂから送信される信号である。基地局５０は、ＲＡＣＨ信号を受信して情報のやり取りを行うことで、無線端末を認識し、基地局５０に接続中の無線端末の情報を管理する。 The RACH receiving unit 55 acquires the RACH preamble from the RACH signal and outputs it to the line establishment processing unit 56. The RACH signal is a signal transmitted from the wireless terminals 70A and B in a random access procedure. The base station 50 receives the RACH signal and exchanges information, thereby recognizing the wireless terminal and managing information on the wireless terminal currently connected to the base station 50.
　回線確立処理部５６は、受信されるＲＡＣＨプリアンブルに基づいて、ランダムアクセス手順を行う。また、回線確立処理部５６は、基地局５０に接続中の無線端末の情報を管理する。例えば、接続中の無線端末の識別情報や、接続中の無線端末への無線リソースの割当て情報が管理される。 The line establishment processing unit 56 performs a random access procedure based on the received RACH preamble. In addition, the line establishment processing unit 56 manages information on wireless terminals currently connected to the base station 50. For example, identification information of a connected wireless terminal and assignment information of a wireless resource to the connected wireless terminal are managed.
　回線混雑判定部５７は、回線が混雑しているか否かを判定する。回線が混雑していると判定された場合、基地局５０の配下の無線端末全体で発生した、優先度が比較的低い送信データに対して、送信の保留を行わせると判定したこととなる。回線混雑判定部５７は、回線が混雑しているか否かを示す回線混雑情報を、データ送信部５８に出力する。回線混雑情報は、例えば回線の混雑度を含む。回線の混雑度は、「回線が混雑している」「回線が混雑していない」の２段階に設定される。回線の混雑度は、２段階に限らず、任意に設定可能である。回線の混雑度は例えば、基地局５０が形成するセル内の上り通信中の無線端末の数、下り通信中の無線端末の数、該セル内の無線端末から基地局５０へ送信すべき上り送信データ量、および基地局５０から該セル内の無線端末へ送信すべき下り送信データ量、の少なくともいずれかに基づいて、判断される。 The line congestion determination unit 57 determines whether or not the line is congested. When it is determined that the line is congested, it is determined that transmission is suspended for transmission data having a relatively low priority that occurs in the entire wireless terminals under the base station 50. The line congestion determination unit 57 outputs line congestion information indicating whether or not the line is congested to the data transmission unit 58. The line congestion information includes, for example, the line congestion level. The degree of line congestion is set in two stages: “line is congested” and “line is not congested”. The congestion level of the line is not limited to two stages, and can be set arbitrarily. For example, the congestion level of the line includes, for example, the number of wireless terminals in uplink communication in the cell formed by the base station 50, the number of wireless terminals in downlink communication, and uplink transmission to be transmitted from the wireless terminals in the cell to the base station 50. The determination is based on at least one of the data amount and the downlink transmission data amount to be transmitted from the base station 50 to the radio terminal in the cell.
　例えば、回線混雑判定部５７は、上りについて、無線端末から送信されてくるBSR(Buffer Status Report)に基づいて、基地局５０配下の（セル内の）無線端末が送信しようとしている上り送信データ量を取得し、この上り送信データ量に基づいて回線の混雑を判定できる。また例えば、回線混雑判定部５７は、データを送信しようとしている無線端末の数をBSRから把握し、この無線端末の数に基づいて回線の混雑を判定できる。また例えば、回線混雑判定部５７は、上りについて、上位ノード（ネットワーク装置３）から配下の無線端末に送信すべき下りデータが送信されてくることから、この下り送信データ量に基づいて回線の混雑を判定できる。また、この下り送信データを送信すべき無線端末が上位ノードから指定されることから、この無線端末の数に基づいて回線の混雑を判定できる。例えば、同一の送信データ量であっても無線端末の数が多いほど制御チャネルなどのオーバーヘッドが大きくなり、混雑度が高まると想定される。 For example, for the uplink, the line congestion determination unit 57, based on the BSR (Buffer Status Report) transmitted from the radio terminal, the uplink transmission data amount that the radio terminal (in the cell) under the base station 50 intends to transmit And congestion of the line can be determined based on the amount of uplink transmission data. Further, for example, the line congestion determination unit 57 can determine the number of wireless terminals that are going to transmit data from the BSR, and determine the line congestion based on the number of wireless terminals. Further, for example, since the downlink data to be transmitted from the upper node (network device 3) to the subordinate radio terminal is transmitted for the uplink, the line congestion determination unit 57 is based on the amount of downlink transmission data. Can be determined. Further, since the radio terminal to which the downlink transmission data is to be transmitted is designated from the upper node, it is possible to determine the congestion of the line based on the number of radio terminals. For example, even if the amount of transmission data is the same, it is assumed that as the number of wireless terminals increases, the overhead of the control channel increases and the degree of congestion increases.
　また、回線混雑判定部５７は、送信の保留が行われている（アクセス制限をかけている）場合に、送信の保留を解除するか（保留されている送信データの送信開始を許可するか）を判定する。回線混雑判定部５７は、送信の保留を解除すると判定した場合、解除情報を解除情報送信部５９に出力する。保留を解除するか否かは、例えば基地局５０の回線の状況に関する情報に基づいて行われる。回線混雑判定部５７は、例えば回線が混雑していないと判定された場合に、保留を解除すると判定する。なお、保留解除の判定条件と、回線混雑の判定条件とは、同じ条件としても、異なる条件としてもよい。また、回線混雑判定部５７は、送信データの優先度が２以上のレベルに設定されている場合に、どのレベルの優先度までのデータに対して保留を解除するかを判定し、解除情報に含めてもよい。 In addition, the line congestion determination unit 57 cancels the transmission suspension when the transmission suspension is performed (access restriction is applied) (whether transmission of the suspended transmission data is permitted to start). Determine. When the line congestion determination unit 57 determines to cancel the suspension of transmission, the line congestion determination unit 57 outputs the cancellation information to the cancellation information transmission unit 59. Whether or not to cancel the hold is performed based on, for example, information regarding the line status of the base station 50. For example, when it is determined that the line is not congested, the line congestion determination unit 57 determines to cancel the hold. Note that the hold cancellation determination condition and the line congestion determination condition may be the same condition or different conditions. In addition, when the priority of transmission data is set to a level of 2 or higher, the line congestion determination unit 57 determines to what level of priority the data is released from the hold and uses the release information as the release information. May be included.
　データ送信部５８は、ユーザデータや制御情報を、予め決められたシグナリングフォーマットに格納する。そして、データ送信部５８は、シグナリングフォーマットに格納されたユーザデータや制御情報に符号化処理や変調処理を行い、送信データを生成して送信信号処理部６０に出力する。制御情報は報知情報を含む。報知情報は回線混雑情報を含む。なお、回線混雑情報は、回線が混雑している（混雑度が所定レベル以上）の場合のみ答申されるものとしてもよい。また、データ送信部５８は、データの復調やチャネル推定に用いられるリファレンス信号を生成して、送信信号処理部６０に出力する。 The data transmission unit 58 stores user data and control information in a predetermined signaling format. The data transmission unit 58 performs encoding processing and modulation processing on user data and control information stored in the signaling format, generates transmission data, and outputs the transmission data to the transmission signal processing unit 60. The control information includes broadcast information. The broadcast information includes line congestion information. The line congestion information may be reported only when the line is congested (the degree of congestion is a predetermined level or higher). In addition, the data transmission unit 58 generates a reference signal used for data demodulation and channel estimation and outputs the reference signal to the transmission signal processing unit 60.
　解除情報送信部５９は、制御情報からＰＣＨ信号を生成して、送信信号処理部６０に出力する。例えばＰＣＨ信号は、回線混雑判定部５７から出力される解除情報を含む。ＰＣＨ信号は、例えば、基地局５０配下の無線端末で共通の、ページング情報を受信するための識別情報P-RNTI（Radio Network Temporary Identifier）が付加されて送信される。なお、ＰＣＨ信号は、物理チャネルとしてはＰＤＳＣＨを用いて送信される。なお、解除情報を含むＰＣＨ信号では、通常時のページング情報の受信のためのP-RNTIと異なる解除用P-RNTIを使用し、通常時と区別するようにしても良い。この解除用P-RNTIは、例えば報知情報として予め通知される。 The cancellation information transmission unit 59 generates a PCH signal from the control information and outputs it to the transmission signal processing unit 60. For example, the PCH signal includes release information output from the line congestion determination unit 57. For example, identification information P-RNTI (RadioTINetwork Temporary Identifier) for receiving paging information, which is common to the radio terminals under the base station 50, is added to the PCH signal and transmitted. The PCH signal is transmitted using PDSCH as a physical channel. In the PCH signal including release information, a release P-RNTI different from the P-RNTI for receiving paging information at the normal time may be used to distinguish from the normal time. This release P-RNTI is notified in advance as broadcast information, for example.
　また、解除情報をＰＣＨ信号で通知する場合、保留が解除された基地局５０の配下の無線端末から一斉にＲＡＣＨ信号が送信される可能性がある。このため、ＰＣＨ信号の中に、各無線端末のアクセス時間をパラメータとして設定し、そのアクセス時間内で各無線端末がランダムにアクセススロットを選ぶことで、ＲＡＣＨ信号の衝突を回避してもよい。 Further, when the release information is notified by the PCH signal, there is a possibility that the RACH signal is transmitted all at once from the radio terminals under the control of the base station 50 whose hold is released. For this reason, the access time of each wireless terminal may be set as a parameter in the PCH signal, and each wireless terminal may randomly select an access slot within the access time, thereby avoiding a RACH signal collision.
　送信信号処理部６０は、送信信号を生成して、送信アンテナ６１に出力する。送信信号処理部６０は、例えば送信データやリファレンス信号についてアンテナポートや無線リソースの割当を行う。また、送信信号処理部６０は例えば、デジタル信号処理や、Ｄ／Ａ（Digital to Analog）変換処理等の無線処理を行い、送信信号を生成する。 The transmission signal processing unit 60 generates a transmission signal and outputs it to the transmission antenna 61. The transmission signal processing unit 60 assigns antenna ports and radio resources for transmission data and reference signals, for example. In addition, the transmission signal processing unit 60 performs radio processing such as digital signal processing and D / A (Digital-to-Analog) conversion processing to generate a transmission signal.
　送信アンテナ６１は、送信信号処理部６０から入力される無線信号を送信する。送信アンテナ６１は、例えば下りのデータチャネルや制御チャネルを介して、下り信号を送信する。信号を送信する物理チャネルは例えば、同期チャネルＰＳＣＨ（Physical Synchronization Channel）、報知チャネルＰＢＣＨ（Physical Broadcast Channel）、ＰＤＳＣＨおよびＰＤＣＣＨを含む。下り信号は、リファレンス信号や、制御信号や、データ信号を含む。 The transmission antenna 61 transmits a radio signal input from the transmission signal processing unit 60. The transmission antenna 61 transmits a downlink signal through, for example, a downlink data channel or a control channel. Physical channels that transmit signals include, for example, a synchronization channel PSCH (Physical Synchronization Channel), a broadcast channel PBCH (Physical Broadcast Channel), PDSCH, and PDCCH. The downlink signal includes a reference signal, a control signal, and a data signal.
　図８は、無線端末７０Ａの機能的構成を示すブロック図である。なお、無線端末７０Ｂの機能的構成およびハードウェア構成は、無線端末７０Ａの機能的構成及びハードウェア構成と同様である。図８に示すように、無線端末７０Ａは、受信アンテナ７１と、受信信号処理部７２と、データ受信部７３と、回線混雑判定部７４と、解除情報受信部７５と、保留解除判定部７６とを有する。また、無線端末７０Ａは、アプリケーション処理部７７と、送信バッファ７８と、データ送信部７９と、アクセス制御部８０と、ＲＡＣＨ送信部８１と、送信信号処理部８２と、送信アンテナ８３とを有する。 FIG. 8 is a block diagram showing a functional configuration of the wireless terminal 70A. The functional configuration and hardware configuration of the wireless terminal 70B are the same as the functional configuration and hardware configuration of the wireless terminal 70A. As shown in FIG. 8, the wireless terminal 70A includes a reception antenna 71, a reception signal processing unit 72, a data reception unit 73, a line congestion determination unit 74, a cancellation information reception unit 75, and a hold cancellation determination unit 76. Have The wireless terminal 70 </ b> A includes an application processing unit 77, a transmission buffer 78, a data transmission unit 79, an access control unit 80, a RACH transmission unit 81, a transmission signal processing unit 82, and a transmission antenna 83.
　受信アンテナ７１は、無線信号を受信して、受信信号処理部７２に出力する。なお、無線端末７０Ａは、受信アンテナを複数備えてもよい。また、無線端末７０Ａは、アンテナを送信と受信とで共用し、アンテナ共用器により切り替えて使用してもよい。 The receiving antenna 71 receives a radio signal and outputs it to the received signal processing unit 72. Note that the wireless terminal 70A may include a plurality of reception antennas. Further, the wireless terminal 70A may share an antenna for transmission and reception, and switch between using an antenna duplexer.
　受信アンテナ７１は、例えば下りのデータチャネルや制御チャネルを介して、下り信号を受信する。受信信号は例えば、ＰＣＨ信号や、リファレンス信号や、制御信号や、データ信号を含む。 The reception antenna 71 receives a downlink signal via, for example, a downlink data channel or a control channel. The received signal includes, for example, a PCH signal, a reference signal, a control signal, and a data signal.
　受信信号処理部７２は、受信信号に、Ａ／Ｄ変換等の無線処理や、ＦＦＴ処理等のデジタル信号処理を行う。受信信号処理部７２は、データ受信部７３に、受信されたデータ信号や、制御信号や、リファレンス信号を出力する。また、受信信号処理部７２は、解除情報受信部７５に、受信されたＰＣＨ信号を出力する。 The reception signal processing unit 72 performs wireless processing such as A / D conversion and digital signal processing such as FFT processing on the reception signal. The reception signal processing unit 72 outputs the received data signal, control signal, and reference signal to the data reception unit 73. Further, the reception signal processing unit 72 outputs the received PCH signal to the cancellation information reception unit 75.
　データ受信部７３は、受信されたデータ信号や制御信号について、復調処理や復号処理を行う。データ受信部７３は例えば、予め通知される或いは格納される制御情報と、復調処理のためのリファレンス信号とに基づいて、復調処理を行う。また、データ受信部５３は、予め通知される或いは格納される制御情報と、チャネル推定のためのリファレンス信号とから推定されるチャネル推定値とに基づいて、復調処理された信号の復号処理を行う。 The data receiving unit 73 performs demodulation processing and decoding processing on the received data signal and control signal. For example, the data receiving unit 73 performs demodulation processing based on control information notified or stored in advance and a reference signal for demodulation processing. Further, the data receiving unit 53 performs a decoding process on the demodulated signal based on the control information notified or stored in advance and the channel estimation value estimated from the reference signal for channel estimation. .
　また、データ受信部７３は、復号処理された受信信号のリオーダリング処理等を行い、データや制御情報を抽出する。抽出されたデータは例えばバッファに格納される。制御情報は例えば報知情報を含む。また、報知情報は例えば回線混雑情報を含む。 In addition, the data receiving unit 73 performs reordering processing of the decoded received signal and extracts data and control information. The extracted data is stored in a buffer, for example. The control information includes notification information, for example. Further, the notification information includes, for example, line congestion information.
　解除情報受信部７５は、受信されたＰＣＨ信号について、復調処理や復号処理を行う。また、解除情報受信部７５は、復号処理された受信信号から制御情報を抽出する。抽出された制御情報は例えば、送信の保留を解除するための解除情報を含む。解除情報受信部７５は、受信された制御情報を、保留解除判定部７６に出力する。詳細には、P-RNTIを用いて、P-RNTIに基づくCRC maskがかかっているＰＤＣＣＨを受信することにより、ＰＣＨが入っているＰＤＳＣＨが受信できる。なお、ＰＤＳＣＨのうちＰＣＨが入っている可能性のあるサブフレームは予め決められている。ＰＣＨには、所定のシグナリングフォーマットPCCH-messageで規定されるシグナリングフォーマットPaging Message内に、解除情報を含む情報が格納されている。 The release information receiving unit 75 performs demodulation processing and decoding processing on the received PCH signal. Also, the release information receiving unit 75 extracts control information from the reception signal subjected to the decoding process. The extracted control information includes, for example, release information for releasing transmission suspension. The release information receiving unit 75 outputs the received control information to the hold release determining unit 76. Specifically, PDSCH containing PCH can be received by using P-RNTI to receive PDCCH that is CRC-masked based on P-RNTI. Note that subframes that may contain PCH in the PDSCH are determined in advance. In the PCH, information including release information is stored in a signaling format Paging Message defined by a predetermined signaling format PCCH-message.
　保留解除判定部７６は、解除情報が受信されたか否かに応じて、送信の保留を解除するか否かを判定する。 The hold cancellation determination unit 76 determines whether or not to cancel the transmission hold depending on whether or not the release information is received.
　回線混雑判定部７４は、基地局５０から受信した回線混雑情報に基づいて、回線が混雑しているか否かを判定する。 The line congestion determination unit 74 determines whether or not the line is congested based on the line congestion information received from the base station 50.
　アクセス制御部８０は、回線の状況に関する情報と、送信データの特性とに基づいて、送信の保留を指示するか否かを判断する。送信データの特性としては、例えば送信データの優先度が挙げられる。アクセス制御部８０は、報知情報で回線が混雑していない（回線の混雑度が所定レベル未満）という情報が得られている場合には、ＲＡＣＨ送信を行うようにＲＡＣＨ送信部８１に指示する。また、アクセス制御部８０は、報知情報で回線が混雑している（回線の混雑度が所定レベル以上）という情報を得ている場合には、送信データの優先度を判定する。優先度が「高」（優先度が所定レベル以上）の場合は、ＲＡＣＨ送信を行うようにＲＡＣＨ送信部８１に指示を出す。また、アクセス制御部８０は、優先度が「低」（優先度が所定レベル未満）の場合は、ＲＡＣＨ送信は一旦保留とし、解除情報を受信したら、ＲＡＣＨ送信を行うようにＲＡＣＨ送信部８１に指示を出す。 The access control unit 80 determines whether or not to instruct suspension of transmission based on the information regarding the state of the line and the characteristics of the transmission data. As the characteristics of the transmission data, for example, the priority of the transmission data can be cited. The access control unit 80 instructs the RACH transmission unit 81 to perform RACH transmission when the broadcast information indicates that the line is not congested (the degree of congestion of the line is less than a predetermined level). Further, the access control unit 80 determines the priority of the transmission data when information indicating that the line is congested (the degree of congestion of the line is equal to or higher than a predetermined level) is obtained from the notification information. When the priority is “high” (priority is equal to or higher than a predetermined level), the RACH transmission unit 81 is instructed to perform RACH transmission. Further, when the priority is “low” (priority is lower than a predetermined level), the access control unit 80 temporarily holds the RACH transmission, and when receiving the release information, the access control unit 80 instructs the RACH transmission unit 81 to perform the RACH transmission. Give instructions.
　送信データの優先度は、無線端末７０Ａに設定されるサービスの種類、送信データを使用するアプリケーションの種類、送信データの論理チャネル番号、および送信データの許容遅延時間の少なくともいずれかに基づいて、前記送信データの優先度を判断する。具体例として、以下のような方法およびこれらの組み合わせで判定することが挙げられる。 The priority of the transmission data is based on at least one of the type of service set in the wireless terminal 70A, the type of application using the transmission data, the logical channel number of the transmission data, and the allowable delay time of the transmission data. Determine the priority of the transmission data. Specific examples include determination by the following methods and combinations thereof.
　第一の方法としては、例えば、論理チャネルに番号を付し、番号と優先度とを予め対応付ける。この対応付けをアプリケーション処理部７７のアプリケーション層（ＯＳ, Operating System）に通知しておく。例えば、Ａ番は即時にデータ送信を開始（優先度が比較的高いレベル）、Ｂ番は指示があるまで保留（優先度が比較的低いレベル）とする。アプリケーション層はアプリケーションに応じて通信層のどの論理チャネルに送信データを送り込むかを決める。 As a first method, for example, a number is assigned to a logical channel, and the number is associated with a priority in advance. This association is notified to the application layer (OS, “Operating System”) of the application processing unit 77. For example, No. A immediately starts data transmission (a level with a relatively high priority), and No. B is suspended (a level with a relatively low priority) until an instruction is given. The application layer determines to which logical channel of the communication layer the transmission data is sent according to the application.
　第二の方法としては、例えば、アプリケーション処理部７７でアプリケーションと優先度とを予め対応付ける。例えば、通話などリアルタイム性が要求されるアプリケーションは優先度が高く設定される。通信層がＰＣＨの受信状況に応じて現在優先度が比較的低いデータの通信が可能かどうかをアプリケーション層に知らせておく。アプリケーション層は、優先度の比較的高いデータであれば通信状態に関係なく通信層にデータを送り、優先度の比較的低いデータであれば、通信状態に応じて通信層にデータを送るかどうかを判断する。 As a second method, for example, the application processing unit 77 associates an application with a priority in advance. For example, a high priority is set for an application such as a call that requires real-time performance. The communication layer notifies the application layer whether or not communication of data with a relatively low current priority is possible according to the PCH reception status. Whether the application layer sends data to the communication layer regardless of the communication status if the data has a relatively high priority, and whether to send data to the communication layer according to the communication status if the data has a relatively low priority Judging.
　第三の方法としては、例えば、通信料金体系を考慮して、混雑時に通信する場合は料金を高く設定し、ユーザはどのレベルのアプリケーションなら高い料金の時間にも通信を開始したいかを端末に設定することが想定される。 As a third method, for example, considering the communication fee system, a high fee is set when communicating during congestion, and the user wants to start communication at a high fee time for any level of application. It is assumed to set.
　第四の方法としては、例えば、ユーザへ提供されるサービス（例えば料金プラン）を考慮して、サービスと優先度とを予め対応付ける。例えば、比較的高い料金プランが選択されているユーザ（無線端末）で発生した送信データの優先度は比較的高く設定される。 As a fourth method, for example, a service and a priority are associated in advance in consideration of a service (for example, a charge plan) provided to a user. For example, the priority of transmission data generated by a user (wireless terminal) that has selected a relatively high rate plan is set to be relatively high.
　また、優先度は、「高い」「低い」の２レベルだけでなく、任意の数のレベルに設定することが可能である。この場合、基地局はどのレベル以上の優先度順位であれば、通常の送信開始動作とし、それ未満の優先順位であれば送信保留とするかの情報を端末に伝えることにより動作可能である。また、ＰＣＨについても、保留解除するデータについてどのレベルの優先度までのデータを対象とするかという情報を追加することも可能である。 Also, the priority can be set to any number of levels as well as two levels of “high” and “low”. In this case, the base station can operate by informing the terminal of information indicating whether the priority order is higher than a normal priority level, and a normal transmission start operation is performed, and if the priority level is lower than that level, the transmission is suspended. In addition, regarding PCH, it is also possible to add information on what level of priority is targeted for data to be released from hold.
　アプリケーション処理部７７は、無線端末７０Ａで実行される、通話やデータ通信等の様々なアプリケーションを管理する。アプリケーション処理部７７は、アプリケーション処理により発生する送信データを送信バッファ７８に出力する。 The application processing unit 77 manages various applications such as telephone calls and data communications executed by the wireless terminal 70A. The application processing unit 77 outputs transmission data generated by application processing to the transmission buffer 78.
　送信バッファ７８は、アプリケーション処理部７７から出力される送信データを格納する。 The transmission buffer 78 stores transmission data output from the application processing unit 77.
　データ送信部７９は、ユーザデータや制御情報を、予め決められたシグナリングフォーマットに格納する。そして、データ送信部７９は、シグナリングフォーマットに格納されたユーザデータや制御情報に符号化処理や変調処理を行い、送信信号処理部８２に出力する。また、データ送信部７９は、データの復調やチャネル推定に用いられるリファレンス信号を生成して、送信信号処理部８２に出力する。また、データ送信部７９は、制御信号を生成して、送信信号処理部８２に出力する。 The data transmission unit 79 stores user data and control information in a predetermined signaling format. Then, the data transmission unit 79 performs encoding processing and modulation processing on the user data and control information stored in the signaling format, and outputs them to the transmission signal processing unit 82. In addition, the data transmission unit 79 generates a reference signal used for data demodulation and channel estimation and outputs the reference signal to the transmission signal processing unit 82. Further, the data transmission unit 79 generates a control signal and outputs it to the transmission signal processing unit 82.
　ＲＡＣＨ送信部８１は、ランダムアクセス手順のためのＲＡＣＨ信号を生成する。無線端末７０Ａは、基地局５０との接続を確立する場合に、ランダムアクセス手順により、基地局５０と呼接続のための情報のやり取りを行う。ＲＡＣＨ送信部８１は、例えば、予め定められたランダムアクセスプリアンブル構成情報から、ＲＡＣＨ信号として所定の信号シーケンスを生成する。 The RACH transmission unit 81 generates a RACH signal for a random access procedure. When establishing a connection with the base station 50, the wireless terminal 70A exchanges information for call connection with the base station 50 by a random access procedure. For example, the RACH transmission unit 81 generates a predetermined signal sequence as a RACH signal from predetermined random access preamble configuration information.
　送信信号処理部８２は、送信信号を生成して、送信アンテナ８３に出力する。送信信号処理部８２は、例えば送信データやリファレンス信号についてアンテナポートや無線リソースの割当を行う。また、送信信号処理部８２は例えば、デジタル信号処理や、Ｄ／Ａ（Digital to Analog）変換処理等の無線処理を行い、送信信号を生成する。 The transmission signal processing unit 82 generates a transmission signal and outputs it to the transmission antenna 83. The transmission signal processing unit 82 allocates antenna ports and radio resources for transmission data and reference signals, for example. Also, the transmission signal processing unit 82 performs radio processing such as digital signal processing and D / A (Digital-to-Analog) conversion processing to generate a transmission signal.
　送信アンテナ８３は、送信信号処理部８２から入力される無線信号を送信する。送信アンテナ８３は、例えば上りのデータチャネルや制御チャネルを介して、上り信号を送信する。信号を送信する物理チャネルは例えば、ＰＲＡＣＨや、ＰＵＳＣＨやＰＵＣＣＨを含む。上り信号は例えば、ＲＡＣＨ信号や、リファレンス信号や、制御信号や、データ信号を含む。なお、無線端末７０Ａは、送信アンテナを複数備えてもよい。 The transmission antenna 83 transmits a radio signal input from the transmission signal processing unit 82. The transmission antenna 83 transmits an uplink signal via, for example, an uplink data channel or a control channel. Physical channels that transmit signals include, for example, PRACH, PUSCH, and PUCCH. The uplink signal includes, for example, a RACH signal, a reference signal, a control signal, and a data signal. The wireless terminal 70A may include a plurality of transmission antennas.
　なお、基地局５０のハードウェア構成は、第１実施形態の基地局１０のハードウェア構成と同様である。基地局５０の受信アンテナ５１と、受信信号処理部５２の無線処理機能と、送信信号処理部６０の無線処理機能と、送信アンテナ６１とは、例えばアンテナおよびＲＦ回路により実現される。また、基地局５０の受信信号処理部５２のデジタル信号処理機能と、送信信号処理部６０のデジタル信号処理機能と、データ受信部５３と、データ転送部５４と、ＲＡＣＨ受信部５５と、回線確立処理部５６と、データ送信部５８と、解除情報送信部５９とは、例えばＣＰＵ等の集積回路により実現される。 Note that the hardware configuration of the base station 50 is the same as the hardware configuration of the base station 10 of the first embodiment. The reception antenna 51 of the base station 50, the radio processing function of the reception signal processing unit 52, the radio processing function of the transmission signal processing unit 60, and the transmission antenna 61 are realized by an antenna and an RF circuit, for example. Also, the digital signal processing function of the reception signal processing unit 52 of the base station 50, the digital signal processing function of the transmission signal processing unit 60, the data reception unit 53, the data transfer unit 54, the RACH reception unit 55, and the line establishment. The processing unit 56, the data transmission unit 58, and the release information transmission unit 59 are realized by an integrated circuit such as a CPU, for example.
　また、無線端末７０Ａのハードウェア構成は、第１実施形態の無線端末２０Ａのハードウェア構成と同様である。無線端末７０Ａの受信アンテナ７１と、受信信号処理部７２の無線処理機能と、送信信号処理部８２の無線処理機能と、送信アンテナ８３とは、例えばアンテナ、およびＲＦ回路により実現される。無線端末７０Ａの受信信号処理部７２の無線処理機能と、送信信号処理部８２の無線処理機能と、データ受信部７３と、回線混雑判定部７４と、解除情報受信部７５と、保留解除判定部７６と、アプリケーション処理部７７と、送信バッファ７８と、データ送信部７９と、アクセス制御部８０と、ＲＡＣＨ送信部８１とは、例えばＣＰＵ等の集積回路により実現される。無線端末７０Ａの送信バッファ７８は、例えばメモリにより実現される。 Further, the hardware configuration of the wireless terminal 70A is the same as the hardware configuration of the wireless terminal 20A of the first embodiment. The reception antenna 71 of the wireless terminal 70A, the wireless processing function of the reception signal processing unit 72, the wireless processing function of the transmission signal processing unit 82, and the transmission antenna 83 are realized by, for example, an antenna and an RF circuit. Radio processing function of reception signal processing unit 72 of radio terminal 70A, radio processing function of transmission signal processing unit 82, data reception unit 73, line congestion determination unit 74, release information reception unit 75, and hold release determination unit 76, the application processing unit 77, the transmission buffer 78, the data transmission unit 79, the access control unit 80, and the RACH transmission unit 81 are realized by an integrated circuit such as a CPU, for example. The transmission buffer 78 of the wireless terminal 70A is realized by a memory, for example.
　次に、第２実施形態における無線通信システムの動作を説明する。図９は、無線通信システムで、無線端末７０Ａ，Ｂでの送信動作を説明するためのシーケンス図である。以下の説明では、前提として、無線端末７０Ａ，Ｂは、待受け状態にあり、また、基地局５０で回線が混雑している状態にある。また、無線端末７０Ａで発生する送信データは優先度が「高」で、無線端末７０Ｂで発生する送信データは優先度が「低」とする。 Next, the operation of the wireless communication system in the second embodiment will be described. FIG. 9 is a sequence diagram for explaining a transmission operation in the wireless terminals 70A and B in the wireless communication system. In the following description, it is assumed that the wireless terminals 70A and 70B are in a standby state and the base station 50 is in a congested line. In addition, the transmission data generated in the wireless terminal 70A has a high priority, and the transmission data generated in the wireless terminal 70B has a low priority.
　図９に示すように、基地局５０は、回線が混雑しているか否かを判定する（Ｓ２１）。回線の混雑の判定は、例えば所定間隔で繰返し実行される。 As shown in FIG. 9, the base station 50 determines whether or not the line is congested (S21). The determination of the congestion of the line is repeatedly executed at a predetermined interval, for example.
　また、基地局５０は、回線混雑情報を、無線端末７０Ａ，Ｂに通知する（Ｓ２２）。回線混雑情報は、例えば基地局５０が形成するセル内に所定間隔で繰返し報知される。 Further, the base station 50 notifies the wireless terminal 70A, B of the line congestion information (S22). For example, the line congestion information is repeatedly reported at predetermined intervals in a cell formed by the base station 50.
　次に、無線端末７０Ａ，Ｂで、送信データが発生する（Ｓ２３）。そして、無線端末７０Ａ，Ｂは、回線混雑情報と、送信データの優先度とに基づいて、送信を保留するか否かを判断する（Ｓ２４）。例えば、回線が混雑していない場合（回線の混雑度が所定レベル未満）、送信を保留しないと判断される。また例えば、回線が混雑している場合（回線の混雑度が所定レベル以上）、送信データの優先度が判定される。そして、送信データの優先度が比較的高い場合、送信を保留しないと判断される。また、送信データの優先度が比較的低い場合、送信を保留すると判断される。 Next, transmission data is generated in the wireless terminals 70A and B (S23). Then, the wireless terminals 70A and 70B determine whether to suspend transmission based on the line congestion information and the priority of the transmission data (S24). For example, when the line is not congested (the degree of congestion of the line is less than a predetermined level), it is determined that the transmission is not suspended. Further, for example, when the line is congested (the degree of congestion of the line is equal to or higher than a predetermined level), the priority of the transmission data is determined. If the priority of the transmission data is relatively high, it is determined that the transmission is not suspended. If the priority of the transmission data is relatively low, it is determined that the transmission is suspended.
　具体的には、無線端末７０Ａは、回線が混雑していて、送信データの優先度が「高」なので、送信を保留しないと判断する。また、無線端末２０Ｂは、回線が混雑していて、送信データの優先度が「低」なので、送信を保留しないと判断する。 Specifically, the wireless terminal 70A determines that the transmission is not suspended because the line is congested and the priority of the transmission data is “high”. Further, the radio terminal 20B determines that the transmission is not suspended because the line is congested and the priority of the transmission data is “low”.
　送信を保留しない場合（Ｓ２４の判断結果がＮｏ）、Ｓ２９に進み、無線端末７０ＡはＲＡＣＨ信号を送信する。そして、基地局５０との間のランダムアクセス手順が実行され、無線端末７０ＡはConnected状態に移行してデータの送信を開始する（Ｓ３０）。一方、送信を保留する場合（Ｓ２４の判断結果がＹｅｓ）、データの送信は開始されず、Ｓ２７に進む。これにより、回線が混雑していない場合は、送信データの特性によらず、送信開始のためのアクセスが実行され、データの送信を開始できる。また、回線が混雑している場合は、優先度が高い送信データは送信開始のためのアクセスが実行され、優先度が比較的低い送信データは送信開始のためのアクセスが保留される。これにより、優先度が比較的低い送信データのためのアクセスが、混雑を助長し他のアクセスを妨げることがなくなり、優先度が比較的高い送信データのアクセスが成功する可能性が高まる。よって、優先度が比較的高い送信データ（即時性が求められるデータ）の送信を開始できると共に、アクセスできずにシグナリングが無駄になることを回避できる。 If the transmission is not suspended (No in S24), the process proceeds to S29, and the wireless terminal 70A transmits a RACH signal. Then, the random access procedure with the base station 50 is executed, and the wireless terminal 70A shifts to the connected state and starts data transmission (S30). On the other hand, when the transmission is suspended (Yes in S24), the data transmission is not started and the process proceeds to S27. As a result, when the line is not congested, access for starting transmission is executed regardless of the characteristics of the transmission data, and data transmission can be started. When the line is congested, transmission data having a high priority is accessed for starting transmission, and transmission data having a relatively low priority is reserved for starting transmission. As a result, access for transmission data with a relatively low priority does not promote congestion and prevent other accesses, and the possibility of successful access of transmission data with a relatively high priority increases. Therefore, transmission of transmission data having relatively high priority (data that requires immediacy) can be started, and it is possible to avoid signaling being wasted due to inaccessibility.
　次に、基地局５０は、送信を保留した無線端末で、送信の保留を解除するか否かを判定する（Ｓ２５）。例えば、基地局５０は、回線が混雑しているか否かを判定し、回線が混雑していないと判定した場合、送信の保留を解除すると判定する。 Next, the base station 50 determines whether or not to cancel the suspension of transmission at the wireless terminal that suspended the transmission (S25). For example, the base station 50 determines whether or not the line is congested. If the base station 50 determines that the line is not congested, the base station 50 determines to cancel the suspension of transmission.
　次に、基地局５０は、送信の保留を解除すると判定された場合に、ＰＣＨ信号を介して解除情報を送信する（Ｓ２６）。 Next, when it is determined that the transmission suspension is canceled, the base station 50 transmits the cancellation information via the PCH signal (S26).
　Ｓ２４の判断結果がＹｅｓで、Ｓ２７に進んだ場合、無線端末７０Ｂは、ＰＣＨ信号の受信処理を行う（Ｓ２７）。そして、無線端末７０Ｂは、解除情報を受信済みか否か判定する（Ｓ２８）。解除情報が受信済みでない場合（Ｓ２８の判断結果がＮｏ）、Ｓ２７に戻る。Ｓ２８の判断結果がＹｅｓとなるまで、無線端末７０Ｂは、ＰＣＨ信号の受信処理を所定間隔で行う。これにより、送信の保留が継続される。 If the determination result in S24 is Yes and the process proceeds to S27, the wireless terminal 70B performs a PCH signal reception process (S27). Then, the wireless terminal 70B determines whether or not the release information has been received (S28). If the release information has not been received (No in S28), the process returns to S27. Until the determination result in S28 is Yes, the wireless terminal 70B performs PCH signal reception processing at predetermined intervals. As a result, transmission suspension is continued.
　一方、解除情報を受信済みの場合（Ｓ２８の判断結果がＹｅｓ）、無線端末７０Ｂは、送信の保留を解除し、Ｓ２９に進み、ＲＡＣＨ信号を送信する。そして、基地局５０との間のランダムアクセス手順が実行され、無線端末７０ＢはConnected状態に移行してデータの送信を開始する（Ｓ３０）。これにより、例えば回線が混雑していない状態になると、送信が保留されていた、優先度が比較的低い送信データの送信開始のためのアクセスが実行される。よって、優先度が比較的低い（ある程度 待機してもよい）送信データの送信を開始できると共に、アクセスできずにシグナリングが無駄になることを回避できる。したがって、即時性が求められる送信データと、ある程度 待機してもよい送信データとを、アクセスできずにシグナリングが無駄になることを回避しつつ、適切なタイミングで送信開始できる。このように、上述の処理によれば、回線状況と送信データの特性とを考慮して、回線の均質化を図ることができる。 On the other hand, when the release information has been received (Yes in S28), the wireless terminal 70B releases the suspension of transmission, proceeds to S29, and transmits a RACH signal. Then, a random access procedure with the base station 50 is executed, and the wireless terminal 70B shifts to the connected state and starts data transmission (S30). As a result, for example, when the line is not congested, access for starting transmission of transmission data having a relatively low priority that has been suspended is executed. Therefore, transmission of transmission data having a relatively low priority (may wait for a certain amount of time) can be started, and it is possible to avoid wasteful signaling due to inaccessibility. Therefore, transmission of transmission data that requires immediateness and transmission data that may wait for a certain amount of time can be started at an appropriate timing while avoiding the loss of signaling due to inaccessibility. Thus, according to the above-described processing, it is possible to homogenize the lines in consideration of the line status and the characteristics of the transmission data.
　以上により、第２実施形態によれば、無線通信システム１において、無線端末からのアクセスを効率良く制御し、通信性能を向上できる。 As described above, according to the second embodiment, in the wireless communication system 1, it is possible to efficiently control access from a wireless terminal and improve communication performance.
［第３実施形態］
　次に、第３実施形態に係る無線通信システムについて説明する。第３実施形態に係る無線通信システムの全体的構成は、第２実施形態の無線通信システムの構成と同様である。以下の説明では、同じ符号を付して説明を省略する。 [Third Embodiment]
Next, a radio communication system according to the third embodiment will be described. The overall configuration of the wireless communication system according to the third embodiment is the same as the configuration of the wireless communication system according to the second embodiment. In the following description, the same reference numerals are given and the description is omitted.
　第３実施形態に係る基地局は、第２実施形態の基地局５０と、回線混雑判定部５７、解除情報送信部５９、および送信信号処理部６０に係る動作が相違する。 The base station according to the third embodiment is different from the base station 50 according to the second embodiment in operations related to the line congestion determination unit 57, the release information transmission unit 59, and the transmission signal processing unit 60.
　第３実施形態において、回線混雑判定部５７は、無線端末をグループ化し、グループ毎に送信の保留の解除を判定し、グループ毎の解除情報を解除情報送信部５９に出力する。グループは、例えば、無線端末に予め割り振られている識別情報、および前記無線端末の位置情報の少なくともいずれかに基づいて分けられる。 In the third embodiment, the line congestion determination unit 57 groups wireless terminals, determines release of transmission suspension for each group, and outputs the release information for each group to the release information transmission unit 59. The group is divided based on, for example, at least one of identification information allocated in advance to the wireless terminal and position information of the wireless terminal.
　例えば、無線端末に予め割り振られている識別情報として、IMSI(International Mobile Subscriber Identity)を用いることができる。IMSIは、全ての携帯電話ユーザに割り当てられている一意な識別番号であり、携帯電話内のSIMカードに格納されている。例えば、IMSIで下位3bitが一致する無線端末を同じグループとする。 For example, IMSI (International Mobile Subscriber Identity) can be used as the identification information allocated in advance to the wireless terminal. IMSI is a unique identification number assigned to all mobile phone users and is stored in a SIM card in the mobile phone. For example, wireless terminals whose lower 3 bits match in IMSI are set as the same group.
　また例えば、無線端末の位置情報により、比較的に近くに存在する無線端末を同じグループとする。この場合、例えば隣接基地局間で連携して、指向性アンテナで、互いに干渉にならない位置のグループを同時に送信許可することにより、受信特性を向上させることができる。 Also, for example, wireless terminals that are relatively close to each other are classified into the same group based on the position information of the wireless terminals. In this case, for example, the reception characteristics can be improved by allowing transmission between groups at positions that do not interfere with each other with a directional antenna in cooperation with adjacent base stations.
　解除情報送信部５９は、ＰＣＨ信号に、解除情報と共にグループ識別情報を含めて、送信信号処理部６０に出力する。 The cancellation information transmission unit 59 includes the group identification information together with the cancellation information in the PCH signal, and outputs it to the transmission signal processing unit 60.
　また、送信信号処理部６０は、ＰＣＨ信号が、グループ毎に異なるタイミングとなるように無線リソースを割り当てて、送信アンテナ６１を介して送信させる。 Further, the transmission signal processing unit 60 allocates radio resources so that the PCH signal has different timing for each group, and transmits the wireless resource via the transmission antenna 61.
　第３実施形態に係る基地局の他の構成は、第２実施形態の基地局５０の構成と同様である。また、第３実施形態に係る基地局のハードウェア構成は、第２実施形態の基地局５０のハードウェア構成と同様である。 Other configurations of the base station according to the third embodiment are the same as the configurations of the base station 50 according to the second embodiment. The hardware configuration of the base station according to the third embodiment is the same as the hardware configuration of the base station 50 according to the second embodiment.
　第３実施形態に係る無線端末は、第２実施形態の無線端末７０Ａと、受信信号処理部７２および解除情報受信部７５に関する動作が相違する。 The wireless terminal according to the third embodiment is different from the wireless terminal 70A of the second embodiment in operations related to the received signal processing unit 72 and the release information receiving unit 75.
　第４実施形態において、解除情報受信部７５に、無線端末７０Ａが含まれるグループに設定されたタイミングで受信されたＰＣＨ信号を出力する。解除情報受信部７５は、受信されたＰＣＨ信号について、復調処理や復号処理を行い、自装置が含まれるグループ宛の解除情報取得し、保留解除判定部７６に出力する。 In the fourth embodiment, the PCH signal received at the timing set in the group including the wireless terminal 70A is output to the release information receiving unit 75. The release information receiving unit 75 performs demodulation processing and decoding processing on the received PCH signal, acquires release information addressed to the group including the own device, and outputs the release information to the hold release determination unit 76.
　第３実施形態に係る無線端末の他の構成は、第２実施形態の無線端末７０Ａの構成と同様である。また、第３実施形態に係る無線端末のハードウェア構成は、第２実施形態の無線端末７０Ａのハードウェア構成と同様である。 Other configurations of the wireless terminal according to the third embodiment are the same as the configuration of the wireless terminal 70A of the second embodiment. The hardware configuration of the wireless terminal according to the third embodiment is the same as the hardware configuration of the wireless terminal 70A of the second embodiment.
　次に、第３実施形態における無線通信システムの動作を説明する。図１０は、第３実施形態における無線通信システムで、無線端末７０Ａ，Ｂでの送信動作を説明するためのシーケンス図である。以下の説明では、前提として、無線端末７０Ａ，Ｂは、待受け状態にあり、また、基地局５０で回線が混雑している状態にある。また、無線端末７０Ａで発生する送信データは優先度が「高」で、無線端末７０Ｂで発生する送信データは優先度が「低」とする。なお、第３実施形態のＳ４１～Ｓ４４、Ｓ４８～Ｓ５０の処理は、第２実施形態のＳ２１～Ｓ２４、Ｓ２８～Ｓ３０の処理と同様である。 Next, the operation of the wireless communication system in the third embodiment will be described. FIG. 10 is a sequence diagram for explaining a transmission operation in the radio terminals 70A and 70B in the radio communication system according to the third embodiment. In the following description, it is assumed that the wireless terminals 70A and 70B are in a standby state and the base station 50 is in a congested line. In addition, the transmission data generated in the wireless terminal 70A has a high priority, and the transmission data generated in the wireless terminal 70B has a low priority. Note that the processing of S41 to S44 and S48 to S50 of the third embodiment is the same as the processing of S21 to S24 and S28 to S30 of the second embodiment.
　図１０に示すように、基地局５０は、回線が混雑しているか否かを判定する（Ｓ４１）。回線の混雑の判定は、例えば所定間隔で繰返し実行される。 As shown in FIG. 10, the base station 50 determines whether or not the line is congested (S41). The determination of the congestion of the line is repeatedly executed at a predetermined interval, for example.
　また、基地局５０は、回線混雑情報を、無線端末７０Ａ，Ｂに通知する（Ｓ４２）。回線混雑情報は、例えば基地局５０が形成するセル内に所定間隔で繰返し報知される。 Further, the base station 50 notifies the wireless terminal 70A, B of the line congestion information (S42). For example, the line congestion information is repeatedly reported at predetermined intervals in a cell formed by the base station 50.
　次に、無線端末７０Ａ，Ｂで、送信データが発生する（Ｓ４３）。そして、無線端末７０Ａ，Ｂは、回線混雑情報と、送信データの優先度とに基づいて、送信を保留するか否かを判断する（Ｓ４４）。例えば、無線端末７０Ａは、回線が混雑していて、送信データの優先度が「高」なので、送信を保留しないと判断する。また、無線端末７０Ｂは、回線が混雑していて、送信データの優先度が「低」なので、送信を保留しないと判断する。 Next, transmission data is generated in the wireless terminals 70A and B (S43). Then, the wireless terminals 70A and 70B determine whether or not to hold the transmission based on the line congestion information and the priority of the transmission data (S44). For example, the wireless terminal 70A determines that the transmission is not suspended because the line is congested and the priority of the transmission data is “high”. The wireless terminal 70B determines that the transmission is not suspended because the line is congested and the priority of the transmission data is “low”.
　送信を保留しない場合（Ｓ４４の判断結果がＮｏ）、Ｓ４９に進み、無線端末７０ＡはＲＡＣＨ信号を送信する。そして、基地局５０との間のランダムアクセス手順が実行され、無線端末７０ＡはConnected状態に移行してデータの送信を開始する。一方、送信を保留する場合（Ｓ４４の判断結果がＹｅｓ）、データの送信は開始されず、Ｓ４７に進む。これにより、回線が混雑していない場合は、送信データの特性によらず、送信開始のためのアクセスが実行され、データの送信を開始できる。また、回線が混雑している場合は、優先度が高い送信データは送信開始のためのアクセスが実行され、優先度が比較的低い送信データは送信開始のためのアクセスが保留される。 If the transmission is not suspended (No in S44), the process proceeds to S49, and the wireless terminal 70A transmits a RACH signal. Then, a random access procedure with the base station 50 is executed, and the wireless terminal 70A shifts to a connected state and starts data transmission. On the other hand, when the transmission is suspended (the determination result in S44 is Yes), the data transmission is not started and the process proceeds to S47. As a result, when the line is not congested, access for starting transmission is executed regardless of the characteristics of the transmission data, and data transmission can be started. When the line is congested, transmission data having a high priority is accessed for starting transmission, and transmission data having a relatively low priority is reserved for starting transmission.
　次に、基地局５０は、送信を保留した無線端末で、送信の保留を解除するか否かを、無線端末のグループ毎に判定する（Ｓ４５）。例えば、基地局５０は、回線が混雑しているか否かを判定し、回線が混雑していないと判定した場合、送信の保留を解除すると判定する。さらに、グループ毎に、保留を解除するタイミングを設定する。また、グループに含まれる各無線端末のアクセス時間を設定し、解除情報に含めてもよい。 Next, the base station 50 determines, for each group of wireless terminals, whether or not to cancel the transmission suspension by the wireless terminals that have suspended transmission (S45). For example, the base station 50 determines whether or not the line is congested. If the base station 50 determines that the line is not congested, the base station 50 determines to cancel the suspension of transmission. Furthermore, the timing for releasing the hold is set for each group. Moreover, the access time of each wireless terminal included in the group may be set and included in the release information.
　次に、基地局５０は、送信の保留を解除すると判定された場合に、グループ毎に設定されたタイミングに応じて、ＰＣＨ信号を介して解除情報を送信する（Ｓ４６）。 Next, when it is determined that the transmission suspension is canceled, the base station 50 transmits the cancellation information via the PCH signal according to the timing set for each group (S46).
　Ｓ４４の判断結果がＮｏで、Ｓ４７に進んだ場合、無線端末７０Ｂは、自装置が含まれるグループ宛てのＰＣＨ信号の受信処理を行う（Ｓ４７）。そして、無線端末２０Ｂは、解除情報を受信済みか否か判定する（Ｓ４８）。解除情報が受信済みでない場合（Ｓ４８の判断結果がＮｏ）、Ｓ４７に戻る。Ｓ４８の判断結果がＮｏとなるまで、無線端末７０Ｂは、ＰＣＨ信号の受信処理を所定間隔で行う。これにより、送信の保留が継続される。 If the determination result in S44 is No and the process proceeds to S47, the wireless terminal 70B performs a process of receiving a PCH signal addressed to the group including the own device (S47). Then, the wireless terminal 20B determines whether or not the release information has been received (S48). If the release information has not been received (No in S48), the process returns to S47. Until the determination result in S48 is No, the wireless terminal 70B performs PCH signal reception processing at predetermined intervals. As a result, transmission suspension is continued.
　一方、解除情報を受信済みの場合（Ｓ４８の判断結果がＹｅｓ）、無線端末７０Ｂは、送信の保留を解除し、Ｓ４９に進み、ＲＡＣＨ信号を送信する。そして、基地局５０との間のランダムアクセス手順が実行され、無線端末７０ＢはConnected状態に移行してデータの送信を開始する。これにより、例えば回線が混雑していない状態になると、送信が保留されていた、優先度が比較的低い送信データの送信開始のためのアクセスが実行される。よって、優先度が比較的低い（ある程度 待機してもよい）送信データの送信を開始できると共に、アクセスできずにシグナリングが無駄になることを回避できる。したがって、即時性が求められる送信データと、ある程度 待機してもよい送信データとを、アクセスできずにシグナリングが無駄になることを回避しつつ、適切なタイミングで送信開始できる。このように、上述の処理によれば、回線状況と送信データの特性とを考慮して、回線の均質化を図ることができる。 On the other hand, if the release information has been received (Yes in S48), the wireless terminal 70B releases the suspension of transmission, proceeds to S49, and transmits a RACH signal. Then, a random access procedure with the base station 50 is executed, and the wireless terminal 70B shifts to the connected state and starts data transmission. As a result, for example, when the line is not congested, access for starting transmission of transmission data having a relatively low priority that has been suspended is executed. Therefore, transmission of transmission data having a relatively low priority (may wait for a certain amount of time) can be started, and it is possible to avoid wasteful signaling due to inaccessibility. Therefore, transmission of transmission data that requires immediateness and transmission data that may wait for a certain amount of time can be started at an appropriate timing while avoiding the loss of signaling due to inaccessibility. Thus, according to the above-described processing, it is possible to homogenize the lines in consideration of the line status and the characteristics of the transmission data.
　また、グループ毎に解除情報が通知されることで、例えばグループ毎に異なるタイミングで送信の保留が解除されるので、一斉に無線端末の送信の保留が解除される場合に比べて、回線が輻輳する可能性を回避することができる。 In addition, because the release information is notified for each group, for example, the transmission suspension is released at different timing for each group, so the line is congested compared to the case where the wireless terminal transmission suspension is released all at once. The possibility of doing so can be avoided.
　以上により、第３実施形態によれば、無線通信システムにおいて、無線端末からのアクセスを効率良く制御し、通信性能を向上できる。 As described above, according to the third embodiment, it is possible to efficiently control access from a wireless terminal and improve communication performance in a wireless communication system.
［第４実施形態］
　次に、第４実施形態に係る無線通信システムについて説明する。第４実施形態に係る無線通信システムの全体的構成は、第２実施形態の無線通信システムの構成と同様である。
以下の説明では、同じ符号を付して説明を省略する。 [Fourth Embodiment]
Next, a radio communication system according to the fourth embodiment will be described. The overall configuration of the wireless communication system according to the fourth embodiment is the same as the configuration of the wireless communication system according to the second embodiment.
In the following description, the same reference numerals are given and the description is omitted.
　第４実施形態に係る基地局は、第２実施形態の基地局５０と、解除情報送信部５９および送信信号処理部６０に係る動作が相違する。 The base station according to the fourth embodiment is different from the base station 50 according to the second embodiment in operations related to the release information transmission unit 59 and the transmission signal processing unit 60.
　第４実施形態において、解除情報送信部５９は、制御情報からPDCCH orderを生成して、送信信号処理部６０に出力する。例えばPDCCH orderは、基地局５０配下のConnected状態の無線端末で上りリンク同期をとるために使用される。また、例えばPDCCH orderは、回線混雑判定部５７から出力される解除情報を含む。PDCCH orderは、例えば、基地局５０配下の各無線端末に割り振られる識別情報Ｃ－ＲＮＴＩ（Radio Network Temporary Identifier）が付加されて送信される。なお、PDCCH orderは、物理チャネルとしてはＰＤＣＣＨを用いて送信される。そして、解除情報送信部５９は、PDCCH orderを送信信号処理部６０に出力し、送信アンテナ６１を介して送信させる。 In the fourth embodiment, the release information transmission unit 59 generates a PDCCH order from the control information and outputs it to the transmission signal processing unit 60. For example, PDCCH order is used for uplink synchronization in a connected wireless terminal under the base station 50. Further, for example, PDCCH order includes release information output from the line congestion determination unit 57. The PDCCH order is transmitted with identification information C-RNTI (Radio Network Temporary Identifier) allocated to each wireless terminal under the base station 50 added thereto, for example. The PDCCH order is transmitted using PDCCH as a physical channel. Then, the release information transmission unit 59 outputs the PDCCH order to the transmission signal processing unit 60 and transmits it via the transmission antenna 61.
　第４実施形態に係る基地局の他の構成は、第２実施形態の基地局５０の構成と同様である。また、第４実施形態に係る基地局のハードウェア構成は、第２実施形態の基地局５０のハードウェア構成と同様である。 Other configurations of the base station according to the fourth embodiment are the same as the configurations of the base station 50 according to the second embodiment. The hardware configuration of the base station according to the fourth embodiment is the same as the hardware configuration of the base station 50 according to the second embodiment.
　第４実施形態に係る無線端末は、第２実施形態の無線端末７０Ａと、受信信号処理部７２および解除情報受信部７５に関する動作が相違する。 The wireless terminal according to the fourth embodiment is different from the wireless terminal 70A of the second embodiment in operations related to the received signal processing unit 72 and the release information receiving unit 75.
　第４実施形態において、受信信号処理部７２は、解除情報受信部７５に、受信されたPDCCH orderを出力する。解除情報受信部７５は、受信されたPDCCH orderについて、復調処理や復号処理を行う。また、解除情報受信部７５は、復号処理された受信信号から制御情報を抽出する。抽出された制御情報は例えば、送信の保留を解除するための解除情報を含む。解除情報受信部７５は、受信された制御情報を、保留解除判定部７６に出力する。詳細には、Ｃ－ＲＮＴＩを用いて、Ｃ－ＲＮＴＩに基づくCRC(Cyclic Redundancy Check) maskがかかっているＰＤＣＣＨを受信できる。 In the fourth embodiment, the received signal processing unit 72 outputs the received PDCCH order to the release information receiving unit 75. The cancellation information receiving unit 75 performs demodulation processing and decoding processing on the received PDCCH order. Also, the release information receiving unit 75 extracts control information from the reception signal subjected to the decoding process. The extracted control information includes, for example, release information for releasing transmission suspension. The release information receiving unit 75 outputs the received control information to the hold release determining unit 76. Specifically, the PDCCH on which CRC (Cyclic Redundancy Check) mask based on C-RNTI is applied can be received using C-RNTI.
　第４実施形態に係る無線端末の他の構成は、第２実施形態の無線端末７０Ａの構成と同様である。また、第４実施形態に係る無線端末のハードウェア構成は、第２実施形態の無線端末７０Ａのハードウェア構成と同様である。 Other configurations of the wireless terminal according to the fourth embodiment are the same as the configuration of the wireless terminal 70A of the second embodiment. The hardware configuration of the wireless terminal according to the fourth embodiment is the same as the hardware configuration of the wireless terminal 70A of the second embodiment.
　次に、第４実施形態における無線通信システムの動作を説明する。図１１は、第４実施形態における無線通信システムで、無線端末７０Ａ，Ｂでの送信動作を説明するためのシーケンス図である。以下の説明では、前提として、無線端末７０Ａ，Ｂは、接続状態（Connected状態）にあり、また、基地局５０で回線が混雑している状態にある。また、無線端末７０Ａで発生する送信データは優先度が「高」で、無線端末７０Ｂで発生する送信データは優先度が「低」とする。 Next, the operation of the wireless communication system in the fourth embodiment will be described. FIG. 11 is a sequence diagram for explaining a transmission operation in the radio terminals 70A and 70B in the radio communication system according to the fourth embodiment. In the following description, as a premise, the wireless terminals 70A and 70B are in a connected state (Connected state), and a line is congested in the base station 50. In addition, the transmission data generated in the wireless terminal 70A has a high priority, and the transmission data generated in the wireless terminal 70B has a low priority.
　図１１に示すように、基地局５０は、回線が混雑しているか否かを判定する（Ｓ６１）。回線の混雑の判定は、例えば所定間隔で繰返し実行される。 As shown in FIG. 11, the base station 50 determines whether or not the line is congested (S61). The determination of the congestion of the line is repeatedly executed at a predetermined interval, for example.
　また、基地局５０は、回線混雑情報を、無線端末７０Ａ，Ｂに通知する（Ｓ６２）。回線混雑情報は、例えば基地局５０が形成するセル内に所定間隔で繰返し報知される。 Further, the base station 50 notifies the wireless terminal 70A, B of the line congestion information (S62). For example, the line congestion information is repeatedly reported at predetermined intervals in a cell formed by the base station 50.
　次に、無線端末７０Ａ，Ｂで、送信データが発生する（Ｓ６３）。そして、無線端末７０Ａ，Ｂは、回線混雑情報と、送信データの優先度とに基づいて、送信を保留するか否かを判断する（Ｓ６４）。例えば、回線が混雑していない場合（回線の混雑度が所定レベル未満）、送信を保留しないと判断される。また例えば、回線が混雑している場合（回線の混雑度が所定レベル以上）、送信データの優先度が判定される。そして、送信データの優先度が比較的高い場合、送信を保留しないと判断される。また、送信データの優先度が比較的低い場合、送信を保留すると判断される。 Next, transmission data is generated in the wireless terminals 70A and B (S63). Then, the wireless terminals 70A and 70B determine whether to suspend transmission based on the line congestion information and the priority of the transmission data (S64). For example, when the line is not congested (the degree of congestion of the line is less than a predetermined level), it is determined that the transmission is not suspended. Further, for example, when the line is congested (the degree of congestion of the line is equal to or higher than a predetermined level), the priority of the transmission data is determined. If the priority of the transmission data is relatively high, it is determined that the transmission is not suspended. If the priority of the transmission data is relatively low, it is determined that the transmission is suspended.
　具体的には、無線端末７０Ａは、回線が混雑していて、送信データの優先度が「高」なので、送信を保留しないと判断する。また、無線端末２０Ｂは、回線が混雑していて、送信データの優先度が「低」なので、送信を保留しないと判断する。 Specifically, the wireless terminal 70A determines that the transmission is not suspended because the line is congested and the priority of the transmission data is “high”. Further, the radio terminal 20B determines that the transmission is not suspended because the line is congested and the priority of the transmission data is “low”.
　送信を保留しない場合（Ｓ６４の判断結果がＮｏ）、Ｓ６９に進み、無線端末７０ＡはＲＡＣＨ信号を送信する。そして、基地局５０との間のランダムアクセス手順が実行され、無線端末７０Ａは上り同期状態に移行してデータの送信を開始する（Ｓ７０）。一方、送信を保留する場合（Ｓ６４の判断結果がＹｅｓ）、データの送信は開始されず、Ｓ６７に進む。これにより、回線が混雑していない場合は、送信データの特性によらず、送信開始のためのアクセスが実行され、データの送信を開始できる。また、回線が混雑している場合は、優先度が高い送信データは送信開始のためのアクセスが実行され、優先度が比較的低い送信データは送信開始のためのアクセスが保留される。これにより、優先度が比較的低い送信データのためのアクセスが、混雑を助長し他のアクセスを妨げることがなくなり、優先度が比較的高い送信データのアクセスが成功する可能性が高まる。よって、優先度が比較的高い送信データ（即時性が求められるデータ）の送信を開始できると共に、アクセスできずにシグナリングが無駄になることを回避できる。 When the transmission is not suspended (No in S64), the process proceeds to S69, and the wireless terminal 70A transmits a RACH signal. Then, a random access procedure with the base station 50 is executed, and the wireless terminal 70A shifts to the uplink synchronization state and starts data transmission (S70). On the other hand, when the transmission is suspended (the determination result of S64 is Yes), the data transmission is not started and the process proceeds to S67. As a result, when the line is not congested, access for starting transmission is executed regardless of the characteristics of the transmission data, and data transmission can be started. When the line is congested, transmission data having a high priority is accessed for starting transmission, and transmission data having a relatively low priority is reserved for starting transmission. As a result, access for transmission data with a relatively low priority does not promote congestion and prevent other accesses, and the possibility of successful access of transmission data with a relatively high priority increases. Therefore, transmission of transmission data having relatively high priority (data that requires immediacy) can be started, and it is possible to avoid signaling being wasted due to inaccessibility.
　次に、基地局５０は、送信を保留した無線端末で、送信の保留を解除するか否かを判定する（Ｓ６５）。例えば、基地局５０は、回線が混雑しているか否かを判定し、回線が混雑していないと判定した場合、送信の保留を解除すると判定する。 Next, the base station 50 determines whether or not to cancel the suspension of transmission at the wireless terminal that suspended the transmission (S65). For example, the base station 50 determines whether or not the line is congested. If the base station 50 determines that the line is not congested, the base station 50 determines to cancel the suspension of transmission.
　次に、基地局５０は、送信の保留を解除すると判定された場合に、PDCCH orderを介して解除情報を送信する（Ｓ６６）。 Next, when it is determined that the transmission suspension is canceled, the base station 50 transmits the cancellation information via the PDCCH order (S66).
　Ｓ６４の判断結果がＮｏで、Ｓ６７に進んだ場合、無線端末７０Ｂは、PDCCH orderの受信処理を行う（Ｓ６７）。そして、無線端末７０Ｂは、解除情報を受信済みか否か判定する（Ｓ６８）。解除情報が受信済みでない場合（Ｓ６８の判断結果がＮｏ）、Ｓ６７に戻る。Ｓ６８の判断結果がＮｏとなるまで、無線端末７０Ｂは、PDCCH orderの受信処理を所定間隔で行う。これにより、送信の保留が継続される。 If the determination result in S64 is No and the process proceeds to S67, the wireless terminal 70B performs a PDCCH order reception process (S67). Then, the wireless terminal 70B determines whether or not the release information has been received (S68). If the release information has not been received (No in S68), the process returns to S67. Until the determination result in S68 is No, the wireless terminal 70B performs PDCCH order reception processing at predetermined intervals. As a result, transmission suspension is continued.
　一方、解除情報を受信済みの場合（Ｓ６８の判断結果がＹｅｓ）、無線端末７０Ｂは、送信の保留を解除し、Ｓ６９に進み、ＲＡＣＨ信号を送信する。そして、基地局５０との間のランダムアクセス手順が実行され、無線端末７０Ｂは上り同期状態に移行してデータの送信を開始する（Ｓ７０）。これにより、例えば回線が混雑していない状態になると、送信が保留されていた、優先度が比較的低い送信データの送信開始のためのアクセスが実行される。よって、優先度が比較的低い（ある程度 待機してもよい）送信データの送信を開始できると共に、アクセスできずにシグナリングが無駄になることを回避できる。したがって、即時性が求められる送信データと、ある程度 待機してもよい送信データとを、アクセスできずにシグナリングが無駄になることを回避しつつ、適切なタイミングで送信開始できる。このように、上述の処理によれば、回線状況と送信データの特性とを考慮して、回線の均質化を図ることができる。 On the other hand, if the release information has been received (Yes in S68), the wireless terminal 70B releases the suspension of transmission, proceeds to S69, and transmits a RACH signal. Then, a random access procedure with the base station 50 is executed, and the wireless terminal 70B shifts to the uplink synchronization state and starts data transmission (S70). As a result, for example, when the line is not congested, access for starting transmission of transmission data having a relatively low priority that has been suspended is executed. Therefore, transmission of transmission data having a relatively low priority (may wait for a certain amount of time) can be started, and it is possible to avoid wasteful signaling due to inaccessibility. Therefore, transmission of transmission data that requires immediateness and transmission data that may wait for a certain amount of time can be started at an appropriate timing while avoiding the loss of signaling due to inaccessibility. Thus, according to the above-described processing, it is possible to homogenize the lines in consideration of the line status and the characteristics of the transmission data.
　以上により、第４実施形態によれば、無線通信システムにおいて、無線端末からのアクセスを効率良く制御し、通信性能を向上できる。 As described above, according to the fourth embodiment, it is possible to efficiently control access from a wireless terminal and improve communication performance in a wireless communication system.
　なお、第４実施形態において、第３実施形態と同様に、基地局は、無線端末をグループ化し、グループ毎に送信の保留の解除を判定し、解除情報を通知してもよい。これによれば、例えばグループ毎に異なるタイミングで送信の保留が解除されるので、一斉に無線端末の送信の保留が解除される場合に比べて、回線が輻輳する可能性を回避することができる。また、個別に解除情報を通知する場合に比べて、シグナリング量が低減される。この場合、例えば、PDCCH orderについて、C-RNTIに代わるグループ識別情報を用いてCRC maskをかけて、グループに含まれる無線端末に一斉に通知してもよい。グループ識別情報は、例えば報知情報として予め通知される。 Note that, in the fourth embodiment, similarly to the third embodiment, the base station may group wireless terminals, determine release of transmission suspension for each group, and notify release information. According to this, since the suspension of transmission is released at a different timing for each group, for example, it is possible to avoid the possibility that the line is congested, compared to the case where the suspension of transmission of wireless terminals is released all at once. . In addition, the amount of signaling is reduced as compared with the case where the release information is individually notified. In this case, for example, the PDCCH order may be simultaneously notified to the wireless terminals included in the group by applying a CRCTImask using group identification information instead of C-RNTI. The group identification information is notified in advance as broadcast information, for example.
　また、グループ化する場合、グループに含まれる無線端末から一斉にＲＡＣＨ信号が送信される可能性がある。このため、PDCCH orderの中に、各無線端末のアクセス時間をパラメータとして設定し、そのアクセス時間内で各無線端末がランダムにアクセススロットを選ぶことで、ＲＡＣＨ信号の衝突を回避してもよい。 In addition, when grouping, RACH signals may be transmitted simultaneously from the wireless terminals included in the group. For this reason, the access time of each wireless terminal may be set as a parameter in the PDCCH order, and each wireless terminal may randomly select an access slot within the access time to avoid RACH signal collision.
　なお、基地局は、配下の全ての無線端末を１つのグループとし、全ての無線端末に対して送信の保留の解除を判定し、解除情報を通知してもよい。 Note that the base station may group all the wireless terminals under its control into one group, determine whether to cancel the suspension of transmission to all the wireless terminals, and notify the cancellation information.
　また、第４実施形態において、解除情報をPDCCH orderを介して送信するものとしたが、例えば、RRC messageを介して送信するものとしてもよい。この場合、C-RNTIを用いて、C-RNTIに基づくCRC maskがかかっているＰＤＣＣＨを受信することで、RRC messageが入っているＰＤＳＣＨを受信できる。 In the fourth embodiment, the release information is transmitted via the PDCCH order, but may be transmitted via the RRC message, for example. In this case, the PDSCH containing the RRC message can be received by receiving the PDCCH on which the CRC mask based on the C-RNTI is applied using the C-RNTI.
　また、第１～第４実施形態の無線通信システムは、例えば、ＬＴＥシステムやＬＴＥ－Ａシステムとして実現できる。なお、ＬＴＥやＬＴＥ－Ａ以外の通信方式を用いた無線通信システムに適用することも可能である。 Further, the wireless communication systems of the first to fourth embodiments can be realized as, for example, an LTE system or an LTE-A system. Note that the present invention can also be applied to a wireless communication system using a communication method other than LTE or LTE-A.
　また、第１～第４実施形態の無線通信システムで、２つの無線端末を有するとしたが、これには限られず、無線端末の数は任意である。 In the wireless communication systems of the first to fourth embodiments, two wireless terminals are provided. However, the present invention is not limited to this, and the number of wireless terminals is arbitrary.
　また、第１～第４実施形態は、無線端末として、携帯電話機、スマートフォン、ＰＤＡ（Personal　Digital　Assistant）などの携帯端末に適用可能である。また、第１～第４実施形態は、その他、移動中継局など、基地局との間で通信を行う様々な通信機器に対して適用可能である。 Also, the first to fourth embodiments can be applied to mobile terminals such as mobile phones, smartphones, and PDAs (Personal Digital Assistants) as wireless terminals. In addition, the first to fourth embodiments can be applied to various communication devices that communicate with a base station such as a mobile relay station.
　また、第１～第４実施形態は、基地局として、マクロ基地局、フェムト基地局など、様々な規模の基地局に適用可能である。また、第１～第４実施形態は、その他、中継局など、移動局との間で通信を行う様々な通信機器に対して適用可能である。 Also, the first to fourth embodiments can be applied to base stations of various sizes such as macro base stations and femto base stations as base stations. In addition, the first to fourth embodiments can be applied to various communication devices that communicate with mobile stations such as relay stations.
　また、基地局、無線端末の各構成要素の分散・統合の具体的態様は、第１～第４実施形態の態様に限定されず、その全部又は一部を、各種の負荷や使用状況等に応じて、任意の単位で機能的又は物理的に分散・統合して構成することもできる。例えば、メモリを、基地局、無線端末の外部装置としてネットワークやケーブル経由で接続するようにしてもよい。 Further, the specific mode of distribution / integration of each component of the base station and the radio terminal is not limited to the mode of the first to fourth embodiments, and all or a part thereof can be used for various loads, usage conditions, and the like. Accordingly, it may be configured to be functionally or physically distributed / integrated in an arbitrary unit. For example, the memory may be connected via a network or a cable as an external device of a base station or a wireless terminal.
　１　無線通信システム
　２　ネットワーク
　３　ネットワーク装置
　１０　基地局
　Ｃ１０　セル
　２０Ａ，Ｂ　無線端末
　１１，２１　送信部
　１２，２２　受信部
　１３，２３　制御部
　３１，４１　アンテナ
　３２，４２　ＲＦ回路
　３３，４３　ＣＰＵ
　３４　ＤＳＰ
　３５，４４　メモリ
　３６　ネットワークＩＦ
　５０　基地局
　５１　受信アンテナ
　５２　受信信号処理部
　５３　データ受信部
　５４　データ転送部
　５５　ＲＡＣＨ受信部
　５６　回線確立処理部
　５７　回線混雑判定部
　５８　データ送信部
　５９　解除情報送信部
　６０　送信信号処理部
　６１　送信アンテナ
　７０Ａ，Ｂ　無線端末
　７１　受信アンテナ
　７２　受信信号処理部
　７３　データ受信部
　７４　回線混雑判定部
　７５　解除情報受信部
　７６　保留解除判定部
　７７　アプリケーション処理部
　７８　送信バッファ
　７９　データ送信部
　８０　アクセス制御部
　８１　ＲＡＣＨ送信部
　８２　送信信号処理部
　８３　送信アンテナ DESCRIPTION OF SYMBOLS 1 Wireless communication system 2 Network 3 Network apparatus 10 Base station C10 Cell 20A, B Radio | wireless terminal 11, 21 Transmission part 12, 22 Reception part 13, 23 Control part 31, 41 Antenna 32, 42 RF circuit 33, 43 CPU
34 DSP
35, 44 Memory 36 Network IF
DESCRIPTION OF SYMBOLS 50 Base station 51 Reception antenna 52 Reception signal processing part 53 Data reception part 54 Data transfer part 55 RACH reception part 56 Line establishment processing part 57 Line congestion determination part 58 Data transmission part 59 Cancellation information transmission part 60 Transmission signal processing part 61 Transmission antenna 70A, B Wireless terminal 71 Reception antenna 72 Received signal processing unit 73 Data reception unit 74 Line congestion determination unit 75 Cancellation information reception unit 76 Hold release determination unit 77 Application processing unit 78 Transmission buffer 79 Data transmission unit 80 Access control unit 81 RACH transmission Unit 82 transmission signal processing unit 83 transmitting antenna

Claims (14)

  1. 　無線通信方法であって、
    　回線の状況に関する情報を基地局（１０，５０）から無線端末（２０Ａ，２０Ｂ，７０Ａ，７０Ｂ）に通知し、
    　前記無線端末（２０Ａ，２０Ｂ，７０Ａ，７０Ｂ）で前記基地局（１０，５０）への送信データが発生した際に、前記回線の状況に関する情報と、前記送信データの特性とに基づいて、前記基地局（１０，５０）への送信の保留を行うか否かを制御する、
    ことを特徴とする無線通信方法。     A wireless communication method,
    Information on the status of the line is notified from the base station (10, 50) to the wireless terminals (20A, 20B, 70A, 70B),
    When transmission data to the base station (10, 50) is generated in the wireless terminals (20A, 20B, 70A, 70B), based on the information on the state of the line and the characteristics of the transmission data, Control whether to defer transmission to the base station (10, 50),
    A wireless communication method.
  2. 　前記保留を解除するための解除情報を前記基地局から前記無線端末に通知し、
    　前記解除情報に応じて前記送信の保留を解除し、前記無線端末から前記基地局への前記送信データの送信を開始する、
    　ことを特徴とする請求項１に記載の無線通信方法。     Release information for releasing the hold from the base station to the wireless terminal,
    Canceling the suspension of transmission according to the cancellation information, and starting transmission of the transmission data from the wireless terminal to the base station,
    The wireless communication method according to claim 1.
  3. 　前記基地局で、複数の前記無線端末をグループに分け、前記グループ毎に前記解除情報を通知する、
    　ことを特徴とする請求項２に記載の無線通信方法。     In the base station, a plurality of the wireless terminals are divided into groups, and the release information is notified for each group.
    The wireless communication method according to claim 2.
  4. 　前記基地局で、前記無線端末に予め割り振られている識別情報、および前記無線端末の位置情報の少なくともいずれかに基づいて前記グループに分ける、
    　ことを特徴とする請求項３に記載の無線通信方法。     In the base station, it is divided into the group based on at least one of identification information pre-allocated to the wireless terminal, and location information of the wireless terminal,
    The wireless communication method according to claim 3.
  5. 　前記基地局で、待受け状態の前記無線端末に対して、前記解除情報を、ＰＣＨ(Paging Channel)信号を介して通知する、
    　ことを特徴とする請求項２～４のいずれかに記載の無線通信方法。     In the base station, the release information is notified to the wireless terminal in a standby state via a PCH (Paging Channel) signal.
    The wireless communication method according to any one of claims 2 to 4, wherein:
  6. 　前記基地局で、接続状態の前記無線端末に対して、前記解除情報を、PDCCH (Physical Downlink Control Channel) order信号又はRRC (Radio Resource Control) message信号を介して通知する、
    　ことを特徴とする請求項２～４のいずれかに記載の無線通信方法。     In the base station, to the wireless terminal in a connected state, the release information is notified via a PDCCH (Physical Downlink Control Channel) order signal or RRC (Radio Resource Control) message signal,
    The wireless communication method according to any one of claims 2 to 4, wherein:
  7. 　前記基地局で、前記回線の状況に関する情報を、前記基地局が形成するセル内へ報知する、
    　ことを特徴とする請求項１～６のいずれかに記載の無線通信方法。     In the base station, information on the status of the line is broadcast in a cell formed by the base station,
    The wireless communication method according to any one of claims 1 to 6, wherein:
  8. 　前記無線端末で、前記送信データの特性として前記送信データの優先度を取得する、
    　ことを特徴とする請求項１～７のいずれかに記載の無線通信方法。     In the wireless terminal, the priority of the transmission data is acquired as a characteristic of the transmission data.
    The wireless communication method according to any one of claims 1 to 7, wherein:
  9. 　前記無線端末で、前記無線端末に設定されるサービスの種類、前記送信データを使用するアプリケーションの種類、前記送信データの論理チャネル番号、および前記送信データの許容遅延時間の少なくともいずれかに基づいて、前記送信データの優先度を判断する、
    　ことを特徴とする請求項８に記載の無線通信方法。     In the wireless terminal, based on at least one of the type of service set in the wireless terminal, the type of application using the transmission data, the logical channel number of the transmission data, and the allowable delay time of the transmission data, Determining the priority of the transmission data;
    The wireless communication method according to claim 8.
  10. 　前記基地局で、前記回線の状況に関する情報として、前記回線の混雑度に関する情報を通知する、
    　ことを特徴とする請求項１～９のいずれかに記載の無線通信方法。     In the base station, as the information on the status of the line, the information on the degree of congestion of the line is notified.
    The wireless communication method according to any one of claims 1 to 9, wherein:
  11. 　前記無線端末で、前記回線の混雑度が所定レベル以上で、かつ前記送信データの優先度が所定レベル未満の場合に、前記基地局への送信の保留を行う、
    　ことを特徴とする請求項１～１０のいずれかに記載の無線通信方法。     In the wireless terminal, when the congestion level of the line is equal to or higher than a predetermined level and the priority of the transmission data is lower than a predetermined level, the transmission to the base station is suspended.
    The wireless communication method according to any one of claims 1 to 10, wherein:
  12. 　基地局と無線端末とを含む無線通信システムであって、
    　前記基地局は、
    　　回線の状況に関する情報を前記無線端末に通知する送信部、を有し、
    　前記無線端末は、
    　　前記基地局への送信データが発生した際に、前記回線の状況に関する情報と、前記送信データの特性とに基づいて、前記基地局への送信の保留を行うか否かを制御する制御部、を有する
    　ことを特徴とする無線通信システム。     A wireless communication system including a base station and a wireless terminal,
    The base station
    A transmission unit for notifying the wireless terminal of information related to the status of the line;
    The wireless terminal is
    When transmission data to the base station occurs, a control unit that controls whether or not to hold transmission to the base station based on information on the state of the line and characteristics of the transmission data, A wireless communication system characterized by comprising:
  13. 　無線通信システムにおける基地局であって、
    　回線の状況に関する情報を無線端末に通知する送信部、を有し、
    　前記回線の状況に関する情報と、前記送信データの特性とに基づいて、前記無線端末で前記基地局への送信データが発生した際に、前記基地局への送信の保留を行うか否かを制御させる、
    　ことを特徴とする基地局。     A base station in a wireless communication system,
    A transmission unit that notifies the wireless terminal of information related to the status of the line;
    Controls whether or not to hold transmission to the base station when transmission data to the base station is generated at the wireless terminal based on the information on the state of the line and the characteristics of the transmission data Let
    A base station characterized by that.
  14. 　無線通信システムにおける無線端末であって、
    　基地局から、回線の状況に関する情報を受信する受信部と、
    　前記基地局への送信データが発生した際に、前記回線の状況に関する情報と、前記送信データの特性とに基づいて、前記基地局への送信の保留を行うか否かを制御する制御部と、
    を有する無線端末。     A wireless terminal in a wireless communication system,
    A receiving unit that receives information about the line status from the base station;
    A control unit that controls whether or not to hold transmission to the base station based on information on the state of the line and characteristics of the transmission data when transmission data to the base station is generated; ,
    A wireless terminal.
PCT/JP2012/004672 2012-07-23 2012-07-23 Wireless communication method, wireless communication system, base station and wireless terminal WO2014016861A1 (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2016066894A (en) * 2014-09-24 2016-04-28 Kddi株式会社 Base station device, terminal device, communication method and communication system
JP2017085516A (en) * 2015-10-30 2017-05-18 日本電気株式会社 Communication system, communication device, control method therefor and program

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2000197088A (en) * 1998-12-25 2000-07-14 Nec Corp Congestion-avoiding method and system for mobile network switchboard
JP2001078260A (en) * 1999-09-06 2001-03-23 Yrp Kokino Idotai Tsushin Kenkyusho:Kk Congestion control method in mobile communication system, mobile terminal and base station
JP2005101982A (en) * 2003-09-25 2005-04-14 Matsushita Electric Ind Co Ltd Method of reducing power consumption of radio communication terminal, radio communications terminal, and radio base station
WO2012073715A1 (en) * 2010-11-30 2012-06-07 株式会社エヌ・ティ・ティ・ドコモ Mobile communication method and mobile station

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2000197088A (en) * 1998-12-25 2000-07-14 Nec Corp Congestion-avoiding method and system for mobile network switchboard
JP2001078260A (en) * 1999-09-06 2001-03-23 Yrp Kokino Idotai Tsushin Kenkyusho:Kk Congestion control method in mobile communication system, mobile terminal and base station
JP2005101982A (en) * 2003-09-25 2005-04-14 Matsushita Electric Ind Co Ltd Method of reducing power consumption of radio communication terminal, radio communications terminal, and radio base station
WO2012073715A1 (en) * 2010-11-30 2012-06-07 株式会社エヌ・ティ・ティ・ドコモ Mobile communication method and mobile station

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2016066894A (en) * 2014-09-24 2016-04-28 Kddi株式会社 Base station device, terminal device, communication method and communication system
JP2017085516A (en) * 2015-10-30 2017-05-18 日本電気株式会社 Communication system, communication device, control method therefor and program

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