WO2010146674A1 - Station de base, station de relais, système de communication et procédé de communication - Google Patents

Station de base, station de relais, système de communication et procédé de communication Download PDF

Info

Publication number
WO2010146674A1
WO2010146674A1 PCT/JP2009/061035 JP2009061035W WO2010146674A1 WO 2010146674 A1 WO2010146674 A1 WO 2010146674A1 JP 2009061035 W JP2009061035 W JP 2009061035W WO 2010146674 A1 WO2010146674 A1 WO 2010146674A1
Authority
WO
WIPO (PCT)
Prior art keywords
relay
station
measurement
unit
base station
Prior art date
Application number
PCT/JP2009/061035
Other languages
English (en)
Japanese (ja)
Inventor
貴夫 中川
Original Assignee
富士通株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 富士通株式会社 filed Critical 富士通株式会社
Priority to PCT/JP2009/061035 priority Critical patent/WO2010146674A1/fr
Publication of WO2010146674A1 publication Critical patent/WO2010146674A1/fr

Links

Images

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W24/00—Supervisory, monitoring or testing arrangements
    • H04W24/10—Scheduling measurement reports ; Arrangements for measurement reports
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W72/00—Local resource management
    • H04W72/04—Wireless resource allocation

Definitions

  • the present invention relates to a base station, a relay station, a communication system, and a communication method that perform wireless communication.
  • BS Base Station
  • UE User Equipment
  • RN Relay Station
  • a base station allocates different radio resources so that interference does not occur in each communication section of the communication system.
  • the above-described conventional technology has a problem that radio resources cannot be used efficiently. For example, if different radio resources are allocated to each communication section, more radio resources are required for the entire communication system. In addition, the bandwidth of the radio resource allocated to each communication section is narrowed and the throughput is reduced.
  • the disclosed base station, relay station, communication system, and communication method are intended to solve the above-described problems and to efficiently use radio resources.
  • this base station reports on the measurement results of interference states of a plurality of relay stations in a base station that performs radio communication with a mobile station via the relay station.
  • a receiving unit that receives a signal, an allocating unit that allocates radio resources to the plurality of relay stations based on a report signal received by the receiving unit, and an allocation signal that indicates each radio resource allocated by the allocating unit And a transmission unit for transmitting to each of the plurality of relay stations.
  • radio resources can be used efficiently.
  • FIG. 1 is a diagram illustrating a communication system according to an embodiment.
  • a communication system 100 according to an embodiment is a communication system that includes a base station BS and relay stations RN1 to RN4, and in which the base station BS and a mobile station perform wireless communication via the relay stations RN1 to RN4. .
  • a straight arrow in FIG. 1 indicates each communication section in the communication system 100.
  • the relay stations RN1 to RN4 are provided in the cell 10 of the base station BS and perform radio communication with the base station BS.
  • the mobile station located in the cell 10 performs radio communication with the base station BS via any one of the relay stations RN1 to RN4 or directly performs radio communication with the base station BS.
  • the mobile station located in the cell 10 may simultaneously perform wireless communication with the base station BS via any one of the relay stations RN1 to RN4 and direct wireless communication with the base station BS.
  • a mobile station located in the cell 10 selects a route with the strongest transmission / reception radio wave intensity, and performs wireless communication with the base station BS through the selected route.
  • the mobile stations 11 to 13 perform radio communication directly with the base station BS.
  • the mobile stations 111 and 112 located in the cell 110 of the relay station RN1 perform radio communication with the base station BS via the relay station RN1.
  • the mobile station 121 located in the cell 120 of the relay station RN2 performs radio communication with the base station BS via the relay station RN2.
  • the mobile stations 131 and 132 located in the cell 130 of the relay station RN3 perform radio communication with the base station BS via the relay station RN3.
  • the mobile stations 141 and 142 located in the cell 140 of the relay station RN4 perform radio communication with the base station BS via the relay station RN4.
  • the base station BS allocates radio resources that can be used in the communication system 100 to each communication section in the communication system 100. At this time, the base station BS allocates radio resources so that radio communications in each communication section do not interfere with each other. Next, radio resources allocated by the base station BS will be described.
  • FIG. 2 is a diagram illustrating an example of radio resources allocated by the base station.
  • the horizontal axis represents time (Time), and the vertical axis represents frequency (Freq.).
  • the radio resources allocated to each communication section by the base station BS shown in FIG. 1 are divided into, for example, a radio resource 210, a radio resource 220, and a radio resource 230.
  • the radio resource 210 is a radio resource allocated for communication between the base station BS and a mobile station (UE).
  • the radio resource 220 is a radio resource allocated for communication between the base station BS and the relay station RN (relay stations RN1 to RN4).
  • the radio resource 230 is a radio resource allocated for communication between the relay station RN and the mobile station (UE).
  • the radio resources 210, 220, and 230 are radio resources divided by frequency.
  • the radio resources 210, 220, and 230 may be radio resources divided by time, radio resources divided by codes, or radio resources divided by a combination thereof. May be.
  • the radio resource 230 is further divided for each of the relay stations RN1 to RN4.
  • relay stations RN1 to RN3 are located sufficiently apart from each other and do not interfere with each other (for example, the interference is small enough to be ignored).
  • relay station RN4 and relay station RN3 are close to each other and interfere with each other.
  • the base station BS allocates the same radio resource to the relay stations RN1, RN2, and RN4.
  • the base station BS allocates the radio resource 231 included in the radio resource 230 to the relay stations RN1, RN2, and RN4. In addition, the base station BS allocates radio resources different from those of the relay stations RN1, RN2, and RN4 to the relay station RN3. For example, the base station BS allocates the radio resource 232 included in the radio resource 230 to the relay station RN3.
  • interference is avoided by allocating different radio resources to relay stations that interfere with each other, and radio resources are made efficient by allocating the same radio resources to relay stations that do not interfere with each other. Use it.
  • radio resource allocation will be described in detail below.
  • FIG. 3 is a diagram illustrating measurement of an interference state between relay stations. 3, parts that are the same as the parts shown in FIG. 1 are given the same reference numerals, and descriptions thereof will be omitted.
  • relay stations RN1 to RN4 transmit measurement signals 311 to 314 to the surroundings, respectively.
  • the measurement signals 311 to 314 are known to each other at the relay stations RN1 to RN4, for example.
  • the signal sequence of the measurement signals 311 to 314 may be a DM-RS (Demodulation Reference Signal) or RACH (Random Access Channel) CAZAC (Constant Amplitude Zero Auto-Relation) signal. Good.
  • DM-RS Demodulation Reference Signal
  • RACH Random Access Channel
  • CAZAC Constant Amplitude Zero Auto-Relation
  • the relay stations RN1 to RN4 sequentially transmit measurement signals to each other, and relay stations that have not transmitted the measurement signal receive measurement signals from other relay stations and measure the amount of interference.
  • the measurement signals are transmitted in the order of relay stations RN1, RN2, RN3, RN4, RN1,.
  • the relay stations RN2 to RN4 measure the amount of interference from the relay station RN1 to the own station by receiving the measurement signal 311.
  • the relay stations RN1 to RN4 can regularly measure the mutual interference amount.
  • the power profiles 321 to 324 indicate the amounts of interference measured at the relay stations RN1 to RN4, respectively.
  • the horizontal axis indicates time
  • the vertical axis indicates the amplitude of the power of the measurement signal.
  • the hatched portions of the power profiles 321 to 324 indicate the timing at which the own station transmits a measurement signal.
  • relay station RN1 since relay station RN1 is located away from any of relay stations RN2 to RN4, the peaks of the interference amounts from relay stations RN2 to RN4 in power profile 321 are all equal to or less than threshold th (OK). Since relay station RN2 is located away from all of relay stations RN1, RN3, and RN4, the peaks of the interference amounts from relay stations RN1, RN3, and RN4 in power profile 322 are all equal to or less than threshold th (OK). ).
  • the relay station RN3 is separated from the relay stations RN1 and RN2, and is close to the relay station RN4. For this reason, the peak of the interference amount from the relay stations RN1 and RN2 in the power profile 323 is equal to or less than the threshold th (OK), and the peak of the interference amount from the relay station RN4 exceeds the threshold th (NG). It can be seen from the power profile 323 that the relay station RN3 receives interference from the relay station RN4.
  • the relay station RN4 is separated from the relay stations RN1 and RN2, and is close to the relay station RN3. For this reason, the peak of the interference amount from the relay stations RN1 and RN2 in the power profile 324 is equal to or less than the threshold th (OK), and the peak of the interference amount from the relay station RN3 exceeds the threshold th (NG). It can be seen from the power profile 324 that the relay station RN4 receives interference from the relay station RN3.
  • the relay stations RN1 to RN4 store, for example, the determination result of whether or not the peak of the interference amount exceeds the threshold th (OK or NG) in the memory of the own station. Then, relay stations RN1 to RN4 periodically measure the amount of interference with each other and update the determination result stored in the memory. Next, reporting of the measurement results of the interference state from the relay stations RN1 to RN4 to the base station BS will be described.
  • FIG. 4 is a diagram illustrating transmission of an interference state report signal from each relay station to the base station. 4, parts that are the same as the parts shown in FIG. 1 are given the same reference numerals, and descriptions thereof will be omitted.
  • the relay stations RN1 to RN4 transmit report signals 411 to 414 indicating the measurement results of the interference state to the base station BS.
  • a report channel is defined between the relay stations RN1 to RN4 and the base station BS, and the relay stations RN1 to RN4 transmit report signals 411 to 414 using the report channel.
  • the report signals 411 to 414 are signals indicating whether or not the amount of interference measured by the relay stations RN1 to RN4 exceeds a threshold (threshold th in FIG. 3) (OK or NG in FIG. 3), for example.
  • the relay station RN1 transmits a report signal 411 indicating that the interference amount of all of the relay stations RN2 to RN4 is equal to or less than a threshold (OK) to the base station BS.
  • relay station RN2 transmits report signal 412 indicating that the interference amount of relay stations RN1, RN3, and RN4 is equal to or less than a threshold value (OK) to base station BS.
  • the relay station RN3 transmits a report signal 413 indicating that the amount of interference from the relay stations RN1 and RN2 is equal to or less than a threshold (OK) and the amount of interference from the relay station RN4 exceeds the threshold (NG). Send to. Further, the relay station RN4 transmits a report signal 414 indicating that the interference amount from the relay stations RN1 and RN2 is equal to or less than the threshold (OK) and the interference amount from the relay station RN3 exceeds the threshold (NG). Send to.
  • the base station BS allocates, for example, the same radio resource to the relay stations RN1 to RN3, and allocates a radio resource different from the relay stations RN1 to RN3 to the relay station RN4.
  • the base station BS may allocate the same radio resources to the relay stations RN1, RN2, and RN4 and allocate radio resources different from those of the relay stations RN1, RN2, and RN4 to the relay station RN3.
  • the same radio resources are allocated to relay stations RN1 and RN2, radio resources different from relay stations RN1 and RN2 are allocated to relay station RN3, and radio stations different from relay stations RN1 to RN3 are allocated to relay station RN4. Resources may be allocated.
  • the base station BS notifies the assigned radio resources to the relay stations RN1 to RN4.
  • Each of relay stations RN1 to RN4 performs radio communication with a mobile station in its own cell using radio resources notified from the base station BS to the own station. In this way, by assigning the same radio resource to each relay station whose mutual interference amount is equal to or less than the threshold value, it is possible to efficiently use the radio resource while suppressing interference between the relay stations.
  • FIG. 5 is a diagram showing the timing of transmission / reception of measurement signals and transmission of report signals.
  • the horizontal axis indicates time (Time).
  • the relay station RN1 first transmits a measurement signal (reference numeral 511).
  • relay stations RN2 to RN4 measure the amount of interference from relay station RN1 (reference numeral 512).
  • relay stations RN2 to RN4 transmit a report signal indicating the measurement result of the interference amount to base station BS (reference numeral 513).
  • the relay station RN2 first transmits a measurement signal (reference numeral 521).
  • relay stations RN1, RN3, and RN4 measure the amount of interference from relay station RN2 (reference numeral 522).
  • the relay stations RN1, RN3, and RN4 transmit a report signal indicating the measurement result of the interference amount to the base station BS (reference numeral 523).
  • the relay station RN3 first transmits a measurement signal (reference numeral 531).
  • relay stations RN1, RN2, and RN4 measure the amount of interference from relay station RN3 (reference numeral 532).
  • the relay stations RN1, RN2, and RN4 transmit a report signal indicating the measurement result of the interference amount to the base station BS (reference numeral 533).
  • the relay station RN4 first transmits a measurement signal (reference numeral 541). Next, relay stations RN1 to RN3 measure the amount of interference from relay station RN4 (reference numeral 542). Next, relay stations RN1 to RN3 transmit a report signal indicating the measurement result of the interference amount to base station BS (reference numeral 543).
  • the mutual interference amount measurement results of the relay stations RN1 to RN4 can be periodically reported to the base station BS.
  • the transmission / reception operation of the measurement signal by the relay stations RN1 to RN4 and the transmission operation of the report signal to the base station BS are performed in the same cycle, but the cycle of each of these operations is not the same. May be.
  • the period of each of these operations may be controlled by the base station BS based on the amount of traffic between the relay stations RN1 to RN4 and the base station BS, or may be set to a predetermined period in advance. Good.
  • the relay stations RN1 to RN4 periodically measure each other's interference amount and report it to the base station BS, so that even if there is a change in the communication environment or a change in the arrangement state of the relay stations, the radio resources are always efficiently and efficiently transmitted. Can be assigned. Changes in the communication environment include, for example, building construction and weather changes.
  • the change in the arrangement state of the relay station is, for example, a temporary increase / decrease in response to an event or the like, or an increase in the step-by-step introduction of the relay station.
  • the relay stations RN1 to RN4 acquire information on the timing of receiving the measurement signals from the own station from the base station BS.
  • This timing information can be obtained from, for example, RN control information transmitted from the base station BS to the relay stations RN1 to RN4.
  • relay stations RN1 to RN4 For example, information indicating that relay stations RN1 to RN4 are allocated to subframes 1 to 4 is transmitted from base station BS to relay stations RN1 to RN4.
  • the relay stations RN1 to RN4 transmit measurement signals in the subframes to which the relay stations correspond.
  • relay stations RN1 to RN4 receive information indicating the transmission timing of the local station from base station BS, and transmit measurement signals at the transmission timing indicated by the received information.
  • information indicating the number of relay stations in the cell 10 may be transmitted from the base station BS to the relay stations RN1 to RN4.
  • the relay stations RN1 to RN4 transmit measurement signals at a timing based on the number of relay stations in the cell 10 and the number of the relay station ID assigned to the own station. For example, each of the relay stations RN1 to RN4 transmits a measurement signal in the order of the relay station ID numbers assigned to the own station, and the last relay station (the relay station ID number is the relay station in the cell 10). The first relay station transmits the measurement signal next.
  • the start timing of the first measurement signal transmission is determined in advance. For example, in subframe 0, it is determined that the first relay station transmits a measurement signal.
  • the base station BS transmits the number of relay stations in the cell 10 to the relay stations RN1 to RN4 using RN control information or the like. The transmission of the RN control information may be performed periodically or when the number of relay stations in the cell 10 changes.
  • the order in which the measurement signals are transmitted in the relay stations RN1 to RN4 is not limited to the order of the relay station ID numbers, but may be a predetermined order.
  • each of the relay stations RN1 to RN4 receives information indicating the number of relay stations including its own station and other relay stations from the base station BS, and sets the transmission timing based on the number indicated by the received information.
  • the measurement signal may be transmitted at the acquired transmission timing.
  • FIG. 6 is a diagram illustrating an example of a radio resource allocation result.
  • a communication system 600 shown in FIG. 6 is a modification of the communication system 100 shown in FIG. 1, and relay stations RN1 to RN10 are arranged in order in a concentric circle surrounding the base station BS.
  • the allocation example 610 in the radio resource 230 shows a case where different radio resources are allocated to the relay stations RN1 to RN10 as a reference. In this case, the relay stations RN1 to RN10 can avoid mutual interference, but the radio resource 230 is further divided into ten radio resources.
  • Example 620 of assignment in radio resource 230 shows a case in relay stations RN1 to RN10 in which different radio resources are assigned to relay stations that interfere with each other and the same radio resource is assigned to relay stations that do not interfere with each other.
  • radio resources 621 are allocated to relay stations RN1, RN3, RN5, RN7, and RN9, and radio resources are allocated to relay stations RN2, RN4, RN6, RN8, and RN10. 622 is assigned.
  • the radio resource 230 is divided into two (radio resources 621 and 622), the relay stations RN1 to RN10 can avoid mutual interference.
  • the allocation example 620 can increase the utilization efficiency of the radio resource by five times compared to the allocation example 610.
  • each of relay stations RN1 to RN10 can perform radio communication using radio resources having a bandwidth five times higher, so that communication quality is improved.
  • the radio resources used by the relay stations RN1 to RN10 are the same, the radio resources used as a whole can be reduced to 1/5.
  • FIG. 7 is a diagram illustrating an example of the configuration of the relay station.
  • relay station 700 shown in FIG. 7 can be used.
  • the relay station 700 includes an antenna 701, an A / D conversion unit 702, a separation unit 703, a DL interference amount measurement unit 704, a DL signal processing unit 705, a DL measurement signal generation unit 706, a synthesis unit 707, D / A conversion unit 708, antenna 709, A / D conversion unit 710, separation unit 711, UL signal processing unit 712, UL interference amount measurement unit 713, interference amount report signal creation unit 714, UL A measurement signal generation unit 715, a synthesis unit 716, and a D / A conversion unit 717 are provided.
  • the antenna 701 is an antenna for performing wireless communication, and performs reception of DL (Down Link) band and transmission of UL (Up Link) band. However, the DL band reception and the UL band transmission may be performed by different antennas.
  • the antenna 701 receives, for example, DL band measurement signals (DL measurement signals) from other relay stations and DL traffic signals (including data and control signals) from the base station BS to the mobile station.
  • the antenna 701 outputs the received signal to the A / D conversion unit 702.
  • the A / D conversion unit 702 converts the signal output from the antenna 701 from analog to digital, and outputs the converted signal to the separation unit 703. Note that an amplifier that amplifies a signal may be provided before or after the A / D conversion unit 702.
  • the separation unit 703 separates the signal output from the A / D conversion unit 702 based on the frequency. Separation section 703 outputs a DL traffic signal included in the signal from A / D conversion section 702 to DL signal processing section 705, and converts a DL measurement signal included in the signal from A / D conversion section 702 into a DL interference amount. Output to the measurement unit 704.
  • the separation unit 703 is an FFT circuit that performs, for example, FFT (Fast Fourier Transform).
  • the DL interference amount measurement unit 704 measures the DL band interference amount (DL interference amount) from the relay station that transmitted the DL measurement signal to the relay station 700 based on the DL measurement signal output from the separation unit 703.
  • the DL interference amount measurement unit 704 outputs the DL interference amount measurement result to the interference amount report signal creation unit 714.
  • the DL interference amount measurement unit 704 may output a measurement result indicating the DL interference amount, or may output a measurement result indicating whether or not the DL interference amount exceeds a threshold value.
  • the DL signal processing unit 705 performs signal processing (see, for example, FIG. 8) of the DL traffic signal output from the separation unit 703, and outputs the DL traffic signal subjected to the signal processing to the combining unit 707.
  • the DL signal processing unit 705 includes the BCH (Broadcast Channel: broadcast signal) and PCH (Paging Channel: paging channel) that the relay station 700 transmits to each mobile station in the DL traffic signal output to the combining unit 707. Also good.
  • the DL measurement signal generation unit 706 generates a DL measurement signal to be transmitted from the relay station 700, and outputs the generated DL measurement signal to the synthesis unit 707.
  • the combining unit 707 combines the DL traffic signal output from the DL signal processing unit 705 and the DL measurement signal output from the DL measurement signal generation unit 706 and outputs the combined signal to the D / A conversion unit 708.
  • the combining unit 707 is an IFFT circuit that performs, for example, IFFT (Inverse FFT: Inverse Fast Fourier Transform).
  • IFFT Inverse FFT: Inverse Fast Fourier Transform.
  • the D / A conversion unit 708 converts the signal output from the synthesis unit 707 from digital to analog, and outputs the converted signal to the antenna 709.
  • the antenna 709 is an antenna for performing wireless communication, and performs, for example, DL band transmission and UL band reception. However, the DL band transmission and the UL band reception may be performed by different antennas.
  • the antenna 709 wirelessly transmits the signal output from the D / A conversion unit 708.
  • the DL traffic signal included in the signal transmitted by the antenna 709 is received by the mobile station. Further, the DL measurement signal included in the signal transmitted by the antenna 709 is received by another relay station.
  • the antenna 709 receives UL band measurement signals (UL measurement signals) from other relay stations and UL traffic signals (for example, including data and control signals) from the mobile station to the base station BS.
  • UL traffic signal received by the antenna 709 may include a RACH signal transmitted by the mobile station.
  • the antenna 709 outputs the received signal to the A / D conversion unit 710.
  • the A / D conversion unit 710 converts the signal output from the antenna 709 from analog to digital, and outputs the converted signal to the separation unit 711. Note that an amplifier that amplifies a signal may be provided before or after the A / D converter 710.
  • the separation unit 711 separates the signal output from the A / D conversion unit 710 according to the frequency.
  • the demultiplexing unit 711 outputs the UL traffic signal included in the signal from the A / D conversion unit 710 to the UL signal processing unit 712 and outputs the UL measurement signal included in the signal from the A / D conversion unit 710 to the UL interference amount. Output to the measurement unit 713.
  • the separation unit 711 is an FFT circuit that performs FFT, for example.
  • the UL signal processing unit 712 performs signal processing on the UL traffic signal output from the separation unit 711 and outputs the UL traffic signal to the combining unit 716.
  • the UL interference amount measurement unit 713 measures the UL band interference amount (UL interference amount) from the relay station that transmitted the UL measurement signal to the relay station 700 based on the UL measurement signal output from the separation unit 711.
  • the UL interference amount measurement unit 713 outputs the measured UL interference amount to the interference amount report signal creation unit 714.
  • the UL interference amount measurement unit 713 may output a measurement result indicating the UL interference amount, or may output a measurement result indicating whether or not the UL interference amount exceeds a threshold value.
  • the interference amount report signal creation unit 714 generates a report signal including the DL interference amount measurement result output from the DL interference amount measurement unit 704 and the UL interference amount measurement result output from the UL interference amount measurement unit 713. create.
  • the interference amount report signal creation unit 714 outputs the created report signal to the synthesis unit 716.
  • UL measurement signal generation section 715 generates a UL measurement signal to be transmitted from relay station 700 and outputs the generated UL measurement signal to combining section 716.
  • the combining unit 716 includes the UL traffic signal output from the UL signal processing unit 712, the report signal output from the interference amount report signal creation unit 714, and the UL measurement signal output from the UL measurement signal generation unit 715. Combined and output to the D / A converter 717.
  • the combining unit 716 is an IFFT circuit that performs, for example, IFFT.
  • the D / A conversion unit 717 converts the signal output from the synthesis unit 716 from digital to analog, and outputs the converted signal to the antenna 701.
  • the antenna 701 wirelessly transmits the signal output from the D / A conversion unit 717.
  • the UL traffic signal included in the signal transmitted by the antenna 701 is received by the base station BS.
  • the UL measurement signal included in the signal transmitted by the antenna 701 is received by another relay station.
  • the relay stations RN1 to RN4 in the communication system 100 often have functions of transmitting and receiving DL bands and transmitting and receiving UL bands. Using this, the relay stations RN1 to RN4 can transmit and receive both the UL measurement signal and the DL measurement signal to each other, and measure the mutual interference amount in each of the UL and DL.
  • FIG. 8 is a diagram illustrating an example of processing of the DL signal processing unit illustrated in FIG.
  • the DL signal processing unit 705 illustrated in FIG. 7 includes a signal point demapping unit 801, a HARQ reception buffer 802, an adding unit 803, a turbo decoding CRC check unit 804, and a CRC addition.
  • a turbo encoding unit 805, a HARQ transmission buffer 806, a switch 807, and a signal point mapping unit 808 are provided.
  • the signal point demapping unit 801 performs signal point demapping of the signal output from the separating unit 703 and outputs the signal subjected to signal point demapping to the adding unit 803.
  • the HARQ reception buffer 802 performs HARQ (Hybrid Automatic Repeat Request) processing. Specifically, the HARQ reception buffer 802 temporarily stores the signal output from the adder 803.
  • the HARQ reception buffer 802 outputs the stored signal to the addition unit 803 when the signal is retransmitted from the signal transmission source.
  • the adder 803 adds the signal output from the signal point demapping unit 801 and the signal output from the HARQ reception buffer 802, and outputs the result to the turbo decoding CRC check unit 804. Temporarily store in the reception buffer 802.
  • the turbo decoding CRC check unit 804 performs turbo decoding CRC (Cyclic Redundancy Check) check on the signal output from the adding unit 803. Then, when an error is detected by the turbo decoding CRC check, the turbo decoding CRC check unit 804 makes a retransmission request to the signal transmission source. Further, the turbo decoding CRC check unit 804 outputs the signal output from the adding unit 803 to the CRC-added turbo coding unit 805 when no error is detected by the turbo decoding CRC check.
  • turbo decoding CRC Cyclic Redundancy Check
  • the CRC-added turbo coding unit 805 performs CRC-added turbo coding on the signal output from the turbo decoding CRC check unit 804, and outputs the signal subjected to CRC-added turbo coding to the switch 807.
  • the switch 807 is connected to the CRC-added turbo encoding unit 805.
  • the HARQ transmission buffer 806 temporarily stores the signal output from the switch 807 to the signal point mapping unit 808, and outputs a stored signal to the switch 807 when a retransmission request is made from the signal transmission destination.
  • the switch 807 connects to the HARQ transmission buffer 806 when a retransmission request is made from a signal transmission destination, and outputs a signal output from the HARQ transmission buffer 806 to the signal point mapping unit 808.
  • the signal is connected to the CRC-added turbo coding unit 805, and the signal output from the CRC-added turbo coding unit 805 is output to the signal point mapping unit 808.
  • the signal point mapping unit 808 performs signal point mapping of the signal output from the switch 807 and outputs the signal subjected to signal point mapping to the combining unit 707.
  • FIG. 8 illustrates an example of the processing of the DL signal processing unit 705 for the DL traffic signal, but the same processing can be applied to the processing of the UL signal processing unit 712 for the UL traffic signal. Further, the processing of the DL signal processing unit 705 and the UL signal processing unit 712 is not limited to the processing shown in FIG. For example, the processing of the DL signal processing unit 705 and the UL signal processing unit 712 may be processing in which part or all of the processing described with reference to FIG. 8 is omitted.
  • FIG. 9 is a diagram illustrating an example of the configuration of the base station.
  • a base station 900 shown in FIG. 9 can be used as the base station BS described above.
  • the base station 900 includes an antenna 901, an A / D conversion unit 902, a separation unit 903, a UL signal processing unit 904, a MAC layer signal processing unit 905, a UL control signal processing unit 906, a scheduler 907, a DL A signal processing unit 908, a DL control signal generation unit 909, a synthesis unit 910, and a D / A conversion unit 911 are provided.
  • the antenna 901 is an antenna for performing wireless communication, and performs, for example, DL band transmission and UL band reception. However, the DL band transmission and the UL band reception may be performed by different antennas.
  • the antenna 901 receives, for example, a report signal from the relay station and a UL traffic signal from the mobile station or relay station to the base station BS.
  • the antenna 901 outputs the received signal to the A / D conversion unit 902.
  • the A / D conversion unit 902 converts the signal output from the antenna 901 from analog to digital, and outputs the converted signal to the separation unit 903. Note that an amplifier that amplifies a signal may be provided before or after the A / D conversion unit 902.
  • the separation unit 903 separates the signal output from the A / D conversion unit 902 based on the frequency.
  • the separation unit 903 outputs data (UL data) included in the signal from the A / D conversion unit 902 to the UL signal processing unit 904.
  • Separation section 903 outputs a control signal included in the signal from A / D conversion section 902 to UL control signal processing section 906.
  • Separation section 903 outputs a report signal included in the signal from A / D conversion section 902 to scheduler 907.
  • the separation unit 903 is an FFT circuit that performs, for example, FFT.
  • the UL signal processing unit 904 performs signal processing such as decoding on the UL data output from the separation unit 903, and outputs the UL data subjected to the signal processing to the MAC layer signal processing unit 905. Further, the UL signal processing unit 904 may output the determination result of the decoding performed in the signal processing to the scheduler 907.
  • the MAC layer signal processing unit 905 performs signal processing of the MAC (Media Access Control) layer of the UL data output from the UL signal processing unit 904, and outputs the signal-processed UL data to the upper layer. Further, the MAC layer signal processing unit 905 outputs data (DL data) output from the upper layer to the DL signal processing unit 908.
  • MAC Media Access Control
  • the UL control signal processing unit 906 performs signal processing such as decoding on the control signal output from the separation unit 903 and outputs the signal to the scheduler 907.
  • the scheduler 907 receives the control signal output from the UL control signal processing unit 906 and various parameters acquired from the upper layer. These control signals and various parameters include, for example, QoS (Quality of Service), traffic volume, and CQI (Channel Quality Indicator) indicating communication quality.
  • the scheduler 907 performs communication scheduling in each communication section in the communication system 100 based on the control signal output from the UL control signal processing unit 906 and various parameters acquired from the upper layer. Further, scheduler 907 assigns radio resources for each relay station between the relay station and the mobile station (between RN and UE) based on the report signal output from demultiplexing section 903. For example, the scheduler 907 assigns the same radio resource to each relay station whose mutual interference amount is equal to or less than the threshold value, and assigns different radio resources to each relay station whose mutual interference amount exceeds the threshold value.
  • the scheduler 907 may preferentially assign radio resources with high communication quality to relay stations whose mutual interference amount is equal to or less than a threshold.
  • Radio resources with high communication quality are radio resources with high CQI, for example.
  • the scheduler 907 may perform retransmission control scheduling based on the decoding determination result output from the UL signal processing unit 904.
  • the scheduler 907 outputs the signal processing parameters obtained by the scheduling to the DL signal processing unit 908.
  • the signal processing parameter is information indicating a modulation scheme, transmission timing, and the like in the DL signal processing unit 908, for example.
  • the scheduler 907 outputs control information obtained by scheduling to the DL control signal generation unit 909.
  • the control information includes, for example, allocation information indicating radio resources allocated to each communication section in the communication system 100.
  • the DL signal processing unit 908 performs signal processing on the DL data output from the MAC layer signal processing unit 905 based on the signal processing parameters output from the scheduler 907 and outputs the DL data to the combining unit 910.
  • the DL control signal generation unit 909 generates a control signal indicating the control information output from the scheduler 907, and outputs the generated control signal to the synthesis unit 910.
  • the synthesizing unit 910 synthesizes the DL data output from the DL signal processing unit 908 and the control signal output from the DL control signal generation unit 909, and outputs the synthesized data to the D / A conversion unit 911.
  • the combining unit 910 is an IFFT circuit that performs, for example, IFFT.
  • the D / A conversion unit 911 converts the signal output from the combining unit 910 from digital to analog, and outputs the converted signal to the antenna 901.
  • the antenna 901 wirelessly transmits the signal output from the D / A conversion unit 911.
  • a signal transmitted by the antenna 901 is received by each mobile station and each relay station in the communication system 100.
  • FIG. 10 is a flowchart showing an example of a radio resource allocation process.
  • the scheduler 907 of the base station 900 performs, for example, the following radio resource allocation process.
  • step S1001 the radio resources allocated to the communication between the base station BS and the mobile station (between BS and UE) in step S1001 are allocated to each mobile station (step S1002).
  • the radio resource allocated to the communication between the base station BS and the relay station (between BS and RN) in step S1001 is allocated to each relay station (RN) (step S1003).
  • step S1004 the radio resources allocated to the communication between the relay station and the mobile station (between RN and UE) in step S1001 are allocated to each relay station (step S1004), and the series of allocation processing ends.
  • wireless resource which can be used in the communication system 100 can be allocated with respect to each communication area of the communication system 100.
  • FIG. 11 is a diagram illustrating an example of a radio resource allocation result by the allocation process illustrated in FIG.
  • the horizontal axis represents time (Time), and the vertical axis represents frequency (Freq.).
  • the radio resource 1110 is allocated for communication between the base station BS and the mobile station (between BS and UE).
  • a radio resource 1120 is allocated for communication between the base station BS and the relay station (between BS and RN).
  • a radio resource 1130 is allocated for communication between the relay station and the mobile station (between RN and UE).
  • Mobile stations that directly communicate with the base station 900 are referred to as mobile stations UE1 to UE4.
  • radio resources 1111 to 1114 included in the radio resource 1110 are allocated to the mobile stations UE1 to UE4, respectively.
  • the mobile station UE1 communicates with the base station 900 using the radio resource 1111.
  • Relay stations that communicate with the base station 900 are relay stations RN1 to RN3.
  • radio resources 1121 to 1123 included in radio resource 1120 are allocated to relay stations RN1 to RN3, respectively.
  • relay station RN1 communicates with base station 900 using radio resource 1121.
  • radio resource 1131 included in radio resource 1130 is assigned to both relay stations RN1 and RN3, and radio resource 1132 included in radio resource 1130 is assigned to relay station RN2.
  • relay stations RN1 and RN3 communicate with the mobile station using the same radio resource 1131.
  • FIG. 12 is a flowchart showing an example of step S1004 of FIG.
  • the report signal transmitted from each relay station is acquired (step S1201).
  • relay stations that are not grouped are extracted from the relay stations included in the report signal in step S1201 (step S1202).
  • step S1203 it is determined whether there is a set of relay stations whose mutual interference amount is equal to or less than a threshold among the relay stations extracted in step S1202 (step S1203). If there is a set of relay stations whose mutual interference amount is equal to or less than the threshold (step S1203: Yes), the set of relay stations is grouped (step S1204), and the process returns to step S1202 to continue the process.
  • step S1203 when there is no set of relay stations whose mutual interference amount is equal to or less than the threshold (step S1203: No), communication between the relay station and the mobile station (between RN and UE) is performed in step S1001 of FIG.
  • the allocated radio resource is allocated to each relay station (step S1205).
  • step S1205 the same radio resource is allocated to relay stations belonging to the same group. Also, different radio resources are allocated to relay stations belonging to different groups or to relay stations that are not grouped.
  • step S1204 if multiple types of grouping are possible, for example, one set having the largest number of relay stations among the set of relay stations that do not interfere with each other is selected, and the selected set is grouped. In this way, by performing grouping so that the number of relay stations to be grouped becomes the largest, it is possible to increase the number of relay stations to which the same radio resource is allocated and to use radio resources more efficiently.
  • FIG. 13 is a diagram illustrating an example of mutual interference states of the relay stations.
  • a table 1300 shown in FIG. 13 shows mutual interference amounts of the relay stations RN1 to RN3 for each of UL and DL.
  • each pair of the relay station RN1 and the relay station RN2, and the relay station RN1 and the relay station RN3 indicates that neither UL nor DL interferes with each other (OK).
  • step S1202 shown in FIG. 12 first, relay stations RN1 to RN3 are extracted as ungrouped relay stations, and in step S1204, for example, relay station RN1 and relay station RN2 are grouped. In step S1205, the same radio resources are allocated to relay stations RN1 and RN2, and radio resources different from those of relay stations RN1 and RN2 are allocated to relay station RN3.
  • LTE Long Term Evolution
  • WiMAX Worldwide Interoperability for Microwave Access
  • resources are allocated in the frequency domain (or time domain). For this reason, different bands may be used for UL (UpLink) and DL (DownLink).
  • the interference state of each medium and light station may differ between UL and DL.
  • the UL band is 2 GHz and the DL band is 800 MHz
  • the 800 MHz band is more likely to interfere with radio wave attenuation and diffraction than the 2 GHz band, so interference occurs in the UL, but no interference occurs in the DL.
  • the UL band is 2 GHz and the DL band is 800 MHz
  • the 800 MHz band is more likely to interfere with radio wave attenuation and diffraction than the 2 GHz band, so interference occurs in the UL, but no interference occurs in the DL.
  • each relay station may measure the interference state for each of the UL band and the DL band.
  • the scheduler 907 of the base station 900 performs the radio resource allocation process shown in FIG. 10 for each of UL and DL. Thereby, the mutual interference state of each relay station can be accurately reflected in the allocation of radio resources.
  • each relay station when one relay station receives interference from the other relay station, but the other relay station does not receive interference from one relay station, the scheduler 907 of the base station 900 Different radio resources may be assigned to. Thereby, the interference in each relay station can be avoided.
  • FIG. 14 is a diagram illustrating an example of radio resource allocation for UL and DL.
  • the horizontal axis represents the frequency (Freq.).
  • a radio resource 1410 having a frequency band of 800 MHz is allocated to the UL
  • a radio resource 1420 having a frequency band of 2 GHz is allocated to the DL.
  • transmission consumes more power for the amplifier than for reception.
  • transmission at a low frequency has less attenuation of radio waves than transmission at a high frequency, when transmitting with the same power, the range over which radio waves reach becomes wider at lower frequencies. For this reason, the power consumption in a mobile terminal can be reduced by assigning a frequency band lower than DL to UL.
  • FIG. 15 is a diagram showing a difference in interference between UL and DL.
  • the same parts as those shown in FIG. When different bands are used for UL and DL, there is a difference in the range in which radio waves reach, and thus a difference also appears in the amount of interference between relay stations.
  • Regions 1511 to 1514 shown in FIG. 15 indicate ranges in which UL radio waves reach by the relay stations RN1 to RN4, respectively.
  • Regions 1521 to 1524 indicate ranges in which DL radio waves reach by relay stations RN1 to RN4, respectively.
  • FIG. 16 is a diagram showing an example of the measurement result of the interference state in the state shown in FIG.
  • the measurement result of the interference state between the relay stations is as shown in a table 1600 of FIG.
  • Table 1600 indicates that the amount of interference between relay station RN3 and relay station RN4 in the UL exceeds a threshold (NG), and the amount of interference is less than the threshold in other communication sections (OK). It is shown that.
  • FIG. 17 is a diagram illustrating an example of a radio resource allocation result based on the measurement result illustrated in FIG. 17, parts that are the same as the parts shown in FIG. 14 are given the same reference numerals, and descriptions thereof will be omitted.
  • the base station BS allocates a radio resource 1711 for communication between the base station BS and the mobile station UE in the UL.
  • the base station BS allocates radio resources 1712 for communication between the base station BS and the relay station RN in the UL. Also, the base station BS allocates radio resources 1713 for communication between the relay stations RN3 and RN4 and the mobile station UE in the UL, and allocates radio resources 1714 for communication between the relay station RN4 and the mobile station UE.
  • the base station BS allocates a radio resource 1721 for communication between the base station BS and the mobile station UE in the DL, and allocates a radio resource 1722 for communication between the base station BS and the relay station RN in the DL. Also, the base station BS allocates radio resources 1723 for communication between the relay stations RN1 to RN4 and the mobile station UE in DL.
  • FIG. 18 is a diagram illustrating another example of the measurement result of the interference state in the state illustrated in FIG.
  • the relay stations RN1 to RN4 may measure the amount of interference in either UL or DL. For example, if the UL band and the DL band are close to each other, the mutual interference amounts in the UL and DL are considered to be substantially the same.
  • the interference state between relay stations can be measured.
  • the amount of interference measurement processing can be reduced.
  • the measurement signal transmitted from each relay station is sufficient as either UL or DL, the information amount of the measurement signal can be reduced.
  • the relay stations that interfere with each other can be accurately determined by measuring the amount of interference in the higher frequency band of UL and DL.
  • FIG. 19 is a diagram showing an example of a radio resource allocation result based on the measurement result shown in FIG. 19, parts that are the same as the parts shown in FIG. 17 are given the same reference numerals, and descriptions thereof will be omitted. As shown in FIG. 19, the assignment of radio resources in the UL based on the measurement result shown in FIG. 18 is the same as the assignment shown in FIG.
  • the communication between the base station BS and the mobile station UE in DL and the communication between the base station BS and the relay station RN in DL are the same as the allocation shown in FIG. Further, the base station BS allocates radio resources 1911 for communication between the relay stations RN1 to RN3 and the mobile station UE in DL, and allocates radio resources 1912 for communication between the relay station RN4 and the mobile station UE in DL. .
  • the amount of interference in the UL is measured, and the measurement result is used for UL and DL scheduling.
  • FIG. 20 is a flowchart showing an example of an interference state measurement operation in the relay station UL.
  • the relay station 700 illustrated in FIG. 7 performs, for example, the following interference state measurement operation in the UL under the control of the control unit included in the relay station 700.
  • step S2001 if it is the transmission timing (step S2001: Yes), the UL measurement signal generator 715 creates a UL measurement signal (step S2002).
  • step S2002 the UL measurement signal created in step S2002 is transmitted to another relay station by the antenna 701 (step S2003), and the series of operations is terminated.
  • step S2001 if it is not time for the local station to transmit the UL measurement signal (step S2001: No), the UL measurement signal from another relay station is received by the antenna 709 (step S2004).
  • step S2004 the UL measurement signal from another relay station is received by the antenna 709 (step S2004).
  • step S2005 the interference amount between the relay station that has transmitted the UL measurement signal and the own station is measured by the UL interference amount measurement unit 713 (step S2005).
  • a report signal indicating the measurement result of the interference amount in step S2005 is created by the interference amount report signal creation unit 714 (step S2006).
  • the report signal created in step S2006 is transmitted to the base station BS via the antenna 701 (step S2007), and the series of operations is terminated.
  • FIG. 21 is a flowchart showing an example of an operation for measuring an interference state in the DL of the relay station.
  • the relay station 700 illustrated in FIG. 7 performs, for example, the following DL interference state measurement operation under the control of the control unit included in the relay station 700.
  • step S2101 if it is the transmission timing (step S2101: Yes), the DL measurement signal generation unit 706 creates a DL measurement signal (step S2102). Next, the DL measurement signal created in step S2102 is transmitted to another relay station by the antenna 709 (step S2103), and the series of operations is terminated.
  • step S2101 if it is not time for the local station to transmit the DL measurement signal (step S2101: No), the antenna 701 receives the DL measurement signal from another relay station (step S2104). Next, based on the DL measurement signal received in step S2104, the amount of interference between the relay station that transmitted the DL measurement signal and the own station is measured by the DL interference amount measurement unit 704 (step S2105).
  • the interference amount report signal creation unit 714 creates a report signal indicating the measurement result of the interference amount in step S2105 (step S2106).
  • the report signal created in step S2106 is transmitted to the base station BS through the antenna 701 (step S2107), and the series of operations is terminated.
  • the relay station 700 shown in FIG. 7 simultaneously performs, for example, the measurement operation of the interference state in the UL (see FIG. 20) and the measurement operation of the interference state in the DL (see FIG. 21).
  • relay station 700 may alternately perform the measurement operation of the interference state in UL and the measurement operation of the interference state in DL.
  • relay stations RN1 to RN4 transmit measurement signals in order to each other, and relay stations that have not transmitted measurement signals receive measurement signals from other relay stations and measure the amount of interference.
  • relay stations RN1 to RN4 can simultaneously transmit and receive measurement signals using RACH used in a wireless communication system.
  • FIG. 22 is a diagram illustrating measurement of an interference state of relay station interference using RACH.
  • RACH for example, a plurality of terminals in the UL band transmit RACH signals (with different RACH sequence numbers) at the same timing, and the receiving side uses a RACH sequence number to distinguish and receive a plurality of RACH signals. is there.
  • each of relay stations RN1 to RN3 in communication system 100 in FIG. 22 includes a RACH circuit (see, for example, FIG. 23).
  • the relay stations RN1 to RN3 transmit RACH signals 2210, 2220, and 2230, respectively.
  • the power profile 2211 indicates the amount of interference corresponding to the sequence number 2 received by the relay station RN1.
  • the power profile 2212 indicates the amount of interference corresponding to the sequence number 3 received by the relay station RN1.
  • the power profile 2221 indicates the amount of interference corresponding to the sequence number 1 received by the relay station RN2.
  • the power profile 2222 indicates the amount of interference corresponding to the sequence number 3 received by the relay station RN2.
  • the power profile 2231 indicates the amount of interference corresponding to the sequence number 1 received by the relay station RN3.
  • Power profile 2232 indicates the amount of interference corresponding to sequence number 2 received by relay station RN3.
  • each RACH signal is shared in advance by the relay stations RN1 to RN3, the power profile for each RACH sequence number can be separated. Therefore, the relay stations RN1 to RN3 can simultaneously transmit and receive the measurement signal. In this case, since the measurement signal can be transmitted and received without performing the timing control for transmitting and receiving the measurement signal, the control can be simplified.
  • FIG. 23 is a diagram illustrating a configuration of a relay station including a RACH circuit.
  • the relay station 700 may include a UL signal processing unit 2310 instead of the UL signal processing unit 712 illustrated in FIG.
  • the UL signal processing unit 2310 includes a RACH signal reception unit 2311, a RACH result report signal generation unit 2312, a traffic signal processing unit 2313, and a determination unit 2314.
  • the separation unit 711 outputs the UL traffic signal included in the signal from the A / D conversion unit 710 and the RACH signal included in the signal from the A / D conversion unit 710 to the RACH signal reception unit 2311.
  • the RACH signal reception unit 2311 receives the RACH signal output from the separation unit 711 and outputs the power profile of the received RACH signal to the RACH result report signal generation unit 2312 and the determination unit 2314.
  • the RACH result report signal generation unit 2312 generates a RACH result report signal indicating the power profile output from the RACH signal reception unit 2311 and outputs the RACH result report signal to the synthesis unit 716.
  • the traffic signal processing unit 2313 performs the same processing as the UL signal processing unit 712 illustrated in FIG. That is, the traffic signal processing unit 2313 performs signal processing on the UL traffic signal output from the separation unit 711 and outputs the signal to the combining unit 716.
  • the determining unit 2314 determines whether or not the peak of the power profile output from the RACH signal receiving unit 2311 exceeds a threshold value. 2314 outputs the determination result to the interference amount report signal creation unit 714.
  • the interference amount report signal creation unit 714 creates a report signal including the DL interference amount measurement result output from the DL interference amount measurement unit 704 and the determination result output from the determination unit 2314.
  • the combining unit 716 includes the RACH result report signal and the UL traffic signal output from the UL signal processing unit 2310, the report signal output from the interference amount report signal creation unit 714, and the UL output from the UL measurement signal generation unit 715. And a measurement signal.
  • the synthesis unit 716 outputs the synthesized signal to the D / A conversion unit 717.
  • FIG. 24 is a diagram illustrating an example of a configuration of a relay station that performs wraparound interference cancellation.
  • a part of the configuration of relay station 700 shown in FIG. 23 is simplified.
  • interference removing section 2410 is provided between separating section 703 and combining section 707.
  • the interference removal unit 2410 performs signal processing of the signal output from the separation unit 703 so as to cancel the sneak signal 2401 to the antenna 701 among the signals transmitted from the antenna 709. Thereby, when transmission and reception of the RACH signal are performed simultaneously, it is possible to avoid a decrease in communication quality due to the sneak signal 2401.
  • FIG. 25 is a diagram showing the addition of base stations to the communication system.
  • a new system such as LTE
  • a new base station BS3 is added to the communication system 2500 in which the base station BS1 and the base station BS2 are operating.
  • interference between the base station BS3 and the base station BS1 is avoided by appropriately setting the radio wave intensity between the newly installed base station BS3 and the already operating base station BS1 (reference numeral 2511). can do.
  • interference between the base station BS2 and the base station BS1 is avoided by appropriately setting the radio wave intensity between the newly installed base station BS3 and the already operating base station BS2 (reference numeral 2512). be able to.
  • FIG. 26 is a diagram illustrating measurement of an interference state between base stations.
  • each of the base stations BS1 to BS3 transmits measurement signals 2611 to 2613 to the surroundings.
  • the measurement signals 2611 to 2613 are signals known to each other at the base stations BS1 to BS3, for example.
  • the signal sequence of the measurement signals 2611 to 2613 may be a CAZAC sequence used in DM-RS or RACH, or another signal sequence.
  • the base stations BS1 to BS3, sequentially transmit measurement signals to each other, and base stations that have not transmitted measurement signals receive measurement signals from other base stations and measure the amount of interference.
  • the measurement signals are transmitted in the order of base stations BS1, BS2, BS3,.
  • the base stations BS2 and BS3 receive the measurement signal 2611 and measure the amount of interference from the base station BS1 to the own station.
  • FIG. 27 is a diagram illustrating transmission of an interference state report signal from each relay station to the base station.
  • the base stations BS1 to BS3 transmit / receive report signals 2711 to 2713 of measurement results of interference states with each other.
  • a report channel is defined between the base stations BS1 to BS3, and the base stations BS1 to BS3 transmit and receive report signals 2711 to 2713 through the defined report channel.
  • Each of the base stations BS1 to BS3 sets its own radio field intensity based on a report signal received from another base station. For example, each of the base stations BS1 to BS3 sets the radio field intensity of the own station so that the amount of interference from the own station to other base stations does not exceed the threshold value. By periodically measuring the interference state between base stations, transmitting and receiving report signals, and setting the radio field intensity, the radio field intensity can be set adaptively even if there are additional base stations. .
  • radio resources can be used efficiently.
  • the base station BS may allocate the same radio resource to each relay station having a smaller amount of mutual interference among the combinations of the relay stations.
  • the same radio resource is allocated to each relay station having a relatively small amount of interference, and the radio resource can be efficiently used while suppressing interference between the relay stations.
  • the same radio resource is allocated for communication between the relay station and the mobile station (between RN and UE) when the relay stations do not interfere with each other.
  • the same radio resource may be allocated for communication between the base station and the relay station (between BS and RN).
  • the mutual interference state of each relay station is not limited thereto.
  • the presence or absence of interference may be measured as the mutual interference state of each relay station, and the same radio resource may be assigned to each relay station that does not have interference.
  • the presence or absence of interference can be determined, for example, based on whether a measurement signal is received.

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Mobile Radio Communication Systems (AREA)

Abstract

Dans un système de communication (100), une communication radio est exécutée entre une station de base (BS) et des stations mobiles (111, 112, 121, 131, 132, 141, 142) par l'intermédiaire de stations de relais (RN1 à RN4). Les stations de relais (RN1 à RN4) mesurent un état d'interférence et émettent un signal de rapport indiquant le résultat de la mesure vers la station de base (BS). La station de base (BS) attribue une ressource radio aux stations de relais (RN1 à RN4) en fonction de chacun des signaux de rapport émis par les stations de relais (RN1 à RN4).
PCT/JP2009/061035 2009-06-17 2009-06-17 Station de base, station de relais, système de communication et procédé de communication WO2010146674A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
PCT/JP2009/061035 WO2010146674A1 (fr) 2009-06-17 2009-06-17 Station de base, station de relais, système de communication et procédé de communication

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/JP2009/061035 WO2010146674A1 (fr) 2009-06-17 2009-06-17 Station de base, station de relais, système de communication et procédé de communication

Publications (1)

Publication Number Publication Date
WO2010146674A1 true WO2010146674A1 (fr) 2010-12-23

Family

ID=43356012

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2009/061035 WO2010146674A1 (fr) 2009-06-17 2009-06-17 Station de base, station de relais, système de communication et procédé de communication

Country Status (1)

Country Link
WO (1) WO2010146674A1 (fr)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2012134368A1 (fr) * 2011-04-01 2012-10-04 Telefonaktiebolaget L M Ericsson (Publ) Limitation de brouillage intra-cellule dans un réseau sans fil employant des nœuds de relais
JP2013081089A (ja) * 2011-10-04 2013-05-02 Nippon Telegr & Teleph Corp <Ntt> 無線通信システム、及びチャネル割当方法
JP2015023519A (ja) * 2013-07-23 2015-02-02 京セラ株式会社 中継局、無線通信システム、および無線通信方法
JP2015513284A (ja) * 2012-04-11 2015-04-30 ノキア ソリューションズ アンド ネットワークス オサケユキチュア 方法及び装置
JP2015099998A (ja) * 2013-11-18 2015-05-28 富士通株式会社 制御装置、中継制御方法、及び通信システム
WO2016059867A1 (fr) * 2014-10-16 2016-04-21 ソニー株式会社 Dispositif de commande de communication, station de base, dispositif terminal, procédé de commande de communication et procédé de communication sans fil
JP7505333B2 (ja) 2020-08-28 2024-06-25 日本電気株式会社 分析装置、モニタ装置、分析システム、干渉判定方法、及びプログラム

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2008044318A1 (fr) * 2006-10-13 2008-04-17 Fujitsu Limited Station de base radio, station relais et procédé de commande de communication
JP2008172771A (ja) * 2007-01-05 2008-07-24 Ind Technol Res Inst 干渉の測定および予測方法

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2008044318A1 (fr) * 2006-10-13 2008-04-17 Fujitsu Limited Station de base radio, station relais et procédé de commande de communication
JP2008172771A (ja) * 2007-01-05 2008-07-24 Ind Technol Res Inst 干渉の測定および予測方法

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2012134368A1 (fr) * 2011-04-01 2012-10-04 Telefonaktiebolaget L M Ericsson (Publ) Limitation de brouillage intra-cellule dans un réseau sans fil employant des nœuds de relais
US9485008B2 (en) 2011-04-01 2016-11-01 Telefonaktiebolaget Lm Ericsson (Publ) Intra cell interference mitigation in a wireless network employing relay nodes
JP2013081089A (ja) * 2011-10-04 2013-05-02 Nippon Telegr & Teleph Corp <Ntt> 無線通信システム、及びチャネル割当方法
JP2015513284A (ja) * 2012-04-11 2015-04-30 ノキア ソリューションズ アンド ネットワークス オサケユキチュア 方法及び装置
US9769024B2 (en) 2012-04-11 2017-09-19 Nokia Solutions And Networks Oy Self-organizing network employing measurement intervals
JP2015023519A (ja) * 2013-07-23 2015-02-02 京セラ株式会社 中継局、無線通信システム、および無線通信方法
JP2015099998A (ja) * 2013-11-18 2015-05-28 富士通株式会社 制御装置、中継制御方法、及び通信システム
WO2016059867A1 (fr) * 2014-10-16 2016-04-21 ソニー株式会社 Dispositif de commande de communication, station de base, dispositif terminal, procédé de commande de communication et procédé de communication sans fil
JPWO2016059867A1 (ja) * 2014-10-16 2017-07-27 ソニー株式会社 通信制御装置、基地局、端末装置、通信制御方法及び無線通信方法
US10075853B2 (en) 2014-10-16 2018-09-11 Sony Corporation Communication control device, base station, terminal device, communication control method, and wireless communication method
US10397806B2 (en) 2014-10-16 2019-08-27 Sony Corporation Communication control device, base station, terminal device, communication control method, and wireless communication method
US11064369B2 (en) 2014-10-16 2021-07-13 Sony Corporation Communication control device, base station, terminal device, communication control method, and wireless communication method
US11736958B2 (en) 2014-10-16 2023-08-22 Sony Group Corporation Communication control device, and communication control method for determining a frequency range to be used by a base station
JP7505333B2 (ja) 2020-08-28 2024-06-25 日本電気株式会社 分析装置、モニタ装置、分析システム、干渉判定方法、及びプログラム

Similar Documents

Publication Publication Date Title
KR102204372B1 (ko) 밀리미터파 이동 광대역 통신 시스템에서 네트워크 진입을 위한 장치 및 방법
RU2319306C2 (ru) Способ и устройство связи
JP4484960B1 (ja) 大セル基地局及び通信制御方法
WO2010146674A1 (fr) Station de base, station de relais, système de communication et procédé de communication
KR101383513B1 (ko) 단말 장치, 통신 시스템 및 통신 방법
US9648484B2 (en) System and method for resource allocation for open discovery in device-to-device communications
US10342041B2 (en) Access to a communications channel in a wireless communications network
WO2011093095A1 (fr) Dispositif de terminal et procédé d&#39;antiparasitage
CN105284066A (zh) 测量自干扰信道的方法及其用户设备
WO2009110689A2 (fr) Procédé de communication dans une station mobile et système équipé de stations relais
JP2011109715A (ja) 通信方法、通信端末及び基地局装置
JP2017500826A (ja) レシーバ方法によるビーム形成重みのセットの決定をサポートするためのトランスミッタ方法、レシーバ方法、トランスミッタ装置、レシーバ装置、およびそのネットワーク・ノード
KR20190055682A (ko) 무선 통신 시스템에서 무선 자원을 결정하기 위한 장치 및 방법
KR20140042889A (ko) Ｏｆｄｍ 피어 발견을 위한 방법들 및 장치
JP4608705B1 (ja) 大セル基地局及び通信制御方法
KR100965673B1 (ko) 이동통신 시스템에서 데이터 송신 방법
JP4607191B2 (ja) スケジューリング方法、基地局および端末
US20130033992A1 (en) Radio base station apparatus and scheduling method
JP5167761B2 (ja) 無線通信システム、基地局、及び送信方法
JP4621797B1 (ja) 大セル基地局及び通信制御方法
US8693443B2 (en) Method for allocating wireless resource, base station, and mobile station
JP5468577B2 (ja) 無線通信システムおよび無線通信方法
JP2016052101A (ja) 無線通信システム、集中制御局、基地局、端末局及び無線通信方法
Balachandran et al. Delay-tolerant autonomous transmissions for short packet communications
JP5366907B2 (ja) 大セル基地局及び通信制御方法

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 09846167

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 09846167

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: JP