WO2009119267A1 - Wireless base station, method of controlling wireless signal, and program - Google Patents

Wireless base station, method of controlling wireless signal, and program Download PDF

Info

Publication number
WO2009119267A1
WO2009119267A1 PCT/JP2009/054054 JP2009054054W WO2009119267A1 WO 2009119267 A1 WO2009119267 A1 WO 2009119267A1 JP 2009054054 W JP2009054054 W JP 2009054054W WO 2009119267 A1 WO2009119267 A1 WO 2009119267A1
Authority
WO
WIPO (PCT)
Prior art keywords
base station
radio base
division duplex
time division
duplex frame
Prior art date
Application number
PCT/JP2009/054054
Other languages
French (fr)
Japanese (ja)
Inventor
輔 北島
Original Assignee
日本電気株式会社
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 日本電気株式会社 filed Critical 日本電気株式会社
Publication of WO2009119267A1 publication Critical patent/WO2009119267A1/en

Links

Images

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B7/00—Radio transmission systems, i.e. using radiation field
    • H04B7/24—Radio transmission systems, i.e. using radiation field for communication between two or more posts
    • H04B7/26—Radio transmission systems, i.e. using radiation field for communication between two or more posts at least one of which is mobile
    • H04B7/2643—Radio transmission systems, i.e. using radiation field for communication between two or more posts at least one of which is mobile using time-division multiple access [TDMA]
    • H04B7/2656—Radio transmission systems, i.e. using radiation field for communication between two or more posts at least one of which is mobile using time-division multiple access [TDMA] for structure of frame, burst
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W72/00—Local resource management
    • H04W72/50—Allocation or scheduling criteria for wireless resources
    • H04W72/54—Allocation or scheduling criteria for wireless resources based on quality criteria
    • H04W72/542—Allocation or scheduling criteria for wireless resources based on quality criteria using measured or perceived quality

Definitions

  • the present invention relates to a radio base station, a radio signal control method, and a program for performing radio communication, and more particularly to a radio base station, a radio signal control method, and a program for performing radio communication using a time division duplex (TDD) frame.
  • TDD time division duplex
  • the frequency used in a radio base station different from the radio base station in the radio base station It becomes a situation where the same frequency must be used.
  • TDD Time Division Duplex
  • a plurality of radio base stations using the same frequency band are adjacent to each other. In such a case, there is a possibility that interference occurs between the radio signals.
  • the same phenomenon may occur when a new radio base station is arranged in order to increase system capacity and coverage with respect to a radio base station already arranged.
  • FIG. 1 is a diagram illustrating an example of the arrangement of radio base stations and terminals that may cause interference.
  • a radio base station 1001-1 and a radio base station 1001-2 are arranged, and a terminal 1003-1 exists in a cell 1002-1 covered by the radio base station 1001-1. . Further, the terminal 1003-2 exists in a portion where the cell 1002-1 and the cell 1002-2 covered by the radio base station 1001-2 overlap.
  • the terminal 1003-2 is communicating with the radio base station 1001-2.
  • the uplink signal transmitted from the terminal 1003-2 to the radio base station 1001-2 (solid line from the terminal 1003-2 to the radio base station 1001-2)
  • Radio base station 1001-1 receives the signal as an interference signal (broken line from terminal 1003-2 to radio base station 1001-1).
  • the interference signal may affect the uplink signal transmitted from the terminal 1003-1 and received by the radio base station 1001-1.
  • FIG. 2 is a diagram showing TDD frame signals that interfere with each other in the arrangement shown in FIG.
  • the transmission timing of the uplink signal transmitted from the terminal 1003-2 matches the reception timing of the uplink signal received by the radio base station 1001-1. Therefore, the uplink signal transmitted from the terminal 1003-2 may interfere with the uplink signal transmitted from the terminal 1003-1 and received by the radio base station 1001-1.
  • FIG. 3 is a diagram illustrating another example of the arrangement of radio base stations and terminals that may cause interference.
  • a radio base station 1001-1 and a radio base station 1001-2 are arranged, and a cell 1002-1 and a radio base station 1001-2 covered by the radio base station 1001-1 are covered.
  • the terminal 1003-1 exists in a portion where the cell 1002-2 to be overlapped.
  • a terminal 1003-2 exists in the cell 1002-2.
  • the terminal 1003-1 is communicating with the radio base station 1001-1.
  • the downlink signal (solid line from the radio base station 1001-2 to the terminal 1003-2) transmitted from the radio base station 1001-2 to the terminal 1003-2 is
  • Terminal 1003-1 receives the signal as an interference signal (broken line from radio base station 1001-2 to terminal 1003-1).
  • the interference signal may affect a downlink signal transmitted from the radio base station 1001-1 and received by the terminal 1003-1.
  • FIG. 4 is a diagram showing TDD frame signals that interfere with each other in the arrangement shown in FIG.
  • the transmission timing of the downlink signal transmitted from the radio base station 1001-2 matches the reception timing of the downlink signal received by the terminal 1003-1. Therefore, the downlink signal transmitted from the radio base station 1001-2 may interfere with the downlink signal transmitted from the radio base station 1001-1 and received by the terminal 1003-1.
  • An object of the present invention is to provide a radio base station, a radio signal control method, and a program that solve the above-described problems.
  • the present invention provides: A radio base station that transmits and receives a first time division duplex frame using a predetermined radio frequency band with a terminal having a radio communication function, When a second time division duplex frame transmitted from a radio base station other than the radio base station is received using the same radio frequency band as the radio frequency band, the received second time division duplex frame is received.
  • a timing setting unit that sets a start timing of transmission of the first time division duplex frame to a timing that does not interfere with the second time division duplex frame;
  • a signal transmission unit configured to transmit the first time division duplex frame to the terminal at the start timing.
  • a radio signal control method for controlling a first time division duplex frame transmitted and received using a predetermined radio frequency band between a terminal having a radio communication function and a radio base station,
  • the received second Setting the start timing of transmission of the first time division duplex frame to a timing that does not interfere with the second time division duplex frame based on the time division duplex frame; Transmitting the first time division duplex frame from the radio base station to the terminal at the start timing.
  • a program for causing a radio base station to transmit and receive the first time division duplex frame using a predetermined radio frequency band with a terminal having a radio communication function In the radio base station, when the second time division duplex frame transmitted from a radio base station other than the radio base station is received using the same radio frequency band as the radio frequency band, the received first A procedure for setting the start timing of transmission of the first time division duplex frame to a timing that does not interfere with the second time division duplex frame based on two time division duplex frames; Transmitting the first time division duplex frame to the terminal at the start timing.
  • the first time When the second time division duplex frame transmitted from the radio base station other than the radio base station is received using the same radio frequency band as that used for transmission / reception of the division duplex frame, the received second time division duplex frame is received. Based on the time division duplex frame, the transmission start timing of the first time division duplex frame is set to a timing that does not interfere with the second time division duplex frame, and the first time is set at the set start timing. Since the divided duplex frame is transmitted to the terminal, radio signal interference can be easily avoided.
  • FIG. 4 is a diagram showing TDD frame signals that interfere in the arrangement shown in FIG. 3. It is a figure which shows one Embodiment of the wireless base station of this invention. It is a figure which shows an example of a structure of the wireless base station shown in FIG. 7 is a flowchart for explaining an example of a radio signal control method performed in the radio base station shown in FIG. 6 in the form shown in FIG. 5.
  • 7 is a flowchart for explaining another example of the radio signal control method performed in the radio base station shown in FIG. 6 in the mode shown in FIG. 5.
  • 7 is a flowchart for explaining an example of a radio signal control method performed by analyzing a TDD frame in the radio base station shown in FIG. 6 in the form shown in FIG. 5.
  • FIG. 5 is a diagram showing an embodiment of the radio base station of the present invention.
  • radio base stations 301-1 to 301-3 that cover cells 302-1 to 302-3 as communication areas, and higher-level devices of the radio base stations 301-1 to 301-3, respectively.
  • a radio base station 101 that covers the cell 102 as a communication area is added.
  • the radio base station 101 is also connected to the control device 201.
  • the cell 102 covered by the radio base station 101 and the cells 302-1 through 302-3 covered by the radio base stations 301-1 through 301-3 respectively have overlapping portions.
  • the radio base stations 101 and 301-1 to 302-3 shown in FIG. 5 are radio base stations connected by performing radio communication with a terminal having a general radio communication function.
  • FIG. 6 is a diagram illustrating an example of the configuration of the radio base station 101 illustrated in FIG.
  • the radio base station 101 illustrated in FIG. 5 includes a signal reception unit 111, a reception power measurement unit 112, a timing setting unit 113, a storage unit 114, and a signal transmission unit 115. ing.
  • the signal receiving unit 111 receives time division duplex frames (hereinafter referred to as TDD frames) that are signals transmitted from the adjacent radio base stations 301-1 to 301-3.
  • TDD frames time division duplex frames
  • the received power measuring unit 112 measures the received power of the TDD frame received by the signal receiving unit 111.
  • the timing setting unit 113 sets the transmission timing of the TDD frame to be transmitted to the terminal connected to the radio base station 101 based on the result measured by the received power measuring unit 112.
  • the storage unit 114 stores the transmission timing set by the timing setting unit 113. Moreover, you may memorize
  • the signal transmission unit 115 transmits the TDD frame to the terminal at the transmission timing set by the timing setting unit 113.
  • FIG. 6 shows only the components related to the present invention among the components of the radio base station 101 shown in FIG.
  • the radio base station 301-1 transmits the TDD frame having the highest received power measured at the radio base station 101.
  • a case of a station will be described as an example.
  • FIG. 7 is a flowchart for explaining an example of the radio signal control method performed by the radio base station 101 shown in FIG. 6 in the form shown in FIG.
  • the TDD frame which is the second time division duplex frame transmitted from the radio base station 301-1, is monitored by being received by the signal receiving unit 111 in step 1.
  • the received power of the TDD frame monitored by the signal receiving unit 111 is measured by the received power measuring unit 112 in step 2.
  • the method generally used may be used.
  • the measured received power is output from the received power measuring unit 112 to the timing setting unit 113 as received power information.
  • the timing setting unit 113 sets the timing for transmitting a TDD frame that is a time division duplex frame.
  • the time (timing) with the lowest received power is set in step 3 to the start timing that means the timing for starting transmission of the TDD frame. This is to determine that the probability of signal interference is the lowest when the reception power when the TDD frame transmitted from the radio base station 301-1 is received by the radio base station 101 is the lowest. .
  • radio frequency band used for transmitting / receiving the first time division duplex frame and the radio frequency band used for transmitting / receiving the second time division duplex frame are the same radio frequency band.
  • FIG. 8 is a graph showing the relationship between the reception power of the TDD frame received by the radio base station 101 and time.
  • the vertical axis represents received power
  • the horizontal axis represents time.
  • a case where a TDD frame is transmitted / received in a frame unit (having a length of 5 ms) having a period of 5 ms as in the WiMAX system will be described as an example.
  • the received power changes with time, and the lowest received power time appears in the frame period.
  • the time at which the received power is lowest is set as the start timing.
  • FIG. 9 is a diagram showing an example of TDD frames transmitted from the radio base stations 101 and 301-1 and their start timings.
  • WiMAX WiMAX
  • a preamble signal which is a pilot signal used for the first is present at the head.
  • a downlink signal subframe (hereinafter referred to as a downlink signal subframe) in which a downlink signal, which is information transmitted from the radio base stations 101 and 301-1, is stored.
  • an uplink signal subframe (hereinafter referred to as an uplink signal subframe) in which an uplink signal transmitted from the terminal to the radio base stations 101 and 301-1 is stored.
  • a TTG that is a gap time for absorbing a propagation delay between the radio base stations 101 and 301-1 and the terminal is provided between the uplink signal subframe and the downlink signal subframe.
  • RTG having the same gap time is provided subsequent to the uplink signal subframe.
  • the downlink signal subframe of the TDD frame is filled with the downlink signal (user burst signal)
  • the lowest reception power time shown in FIG. 8 is transmitted from the radio base station 301-1 shown in FIG.
  • the transmission completion time of the downlink signal subframe of the TDD frame is transmitted.
  • This user burst signal is a downlink signal transmitted from the radio base stations 101, 301-1 to 301-3 to the terminal, and is transmitted in a downlink signal subframe.
  • the start timing of the TDD frame transmitted from the radio base station 101 to the terminal is transmitted from the radio base station 301-1 as shown in FIG.
  • the transmission completion time of the downlink signal subframe of the TDD frame to be transmitted is a high possibility that it will be the transmission completion time of the downlink signal subframe of the TDD frame to be transmitted.
  • the TDD frame is transmitted from the signal transmission unit 115 to the terminal in step 4.
  • a predetermined threshold value may be stored in advance in the storage unit 114 illustrated in FIG. 6, and the start timing may be set based on a comparison result between the stored threshold value and the received power.
  • FIG. 10 is a flowchart for explaining another example of the radio signal control method performed in the radio base station 101 shown in FIG. 6 in the form shown in FIG.
  • the TDD frame transmitted from the radio base station 301-1 is monitored by being received by the signal receiving unit 111 in step 11.
  • the received power of the TDD frame monitored by the signal receiving unit 111 is measured by the received power measuring unit 112 in step 12.
  • the method generally used may be used.
  • the measured received power is output from the received power measuring unit 112 to the timing setting unit 113 as received power information.
  • the threshold value stored in advance in the storage unit 114 is read by the timing setting unit 113. Then, the threshold read from the storage unit 114 and the received power indicated by the received power information input to the timing setting unit 113 are compared in step 13.
  • the threshold value stored in the storage unit 114 is set by calculating in advance the value of the received power of another signal that does not interfere with the signal transmitted from the radio base station 101 to the terminal.
  • the timing setting unit 113 sets the timing for transmitting the TDD frame from the radio base station 101 to the terminal connected to the radio base station 101 based on the comparison result.
  • the time when the received power is lower than the threshold is set as the start timing in step 14. This is because when the TDD frame transmitted from the radio base station 301-1 is received by the radio base station 101, the probability that signal interference will occur is low when the received power is lower than the threshold. is there.
  • the TDD frame is transmitted from the signal transmission unit 115 to the terminal in step 15 at the start timing set by the timing setting unit 113 in this way.
  • the start timing may be set by analyzing the TDD frame received by the signal receiving unit 111 by the timing setting unit 113. At this time, the reception power measurement unit 112 does not measure the reception power.
  • FIG. 11 is a flowchart for explaining an example of a radio signal control method performed by analyzing the TDD frame in the radio base station 101 shown in FIG. 6 in the form shown in FIG.
  • the received TDD frame is analyzed in the timing setting unit 113 in step 32.
  • the MAP information is stored at the head of the downlink signal subframe, and is information indicating how uplink signals and downlink signals (user burst signals) are mapped in the frame. Then, based on the downlink signal indicated in the MAP information, the start timing of the TDD frame transmitted from the radio base station 101 to the terminal is set in step 33. Specifically, it is set to the transmission completion time of the downlink signal (user burst signal) in the downlink signal subframe of the TDD frame transmitted from the radio base station 301-1.
  • the TDD frame is transmitted from the signal transmission unit 115 to the terminal in step 34 at the start timing set by the timing setting unit 113 in this way.
  • the above-described form is a form in which the radio base station 101 is added to increase the coverage.
  • a mode in which the radio base station 101 is added to increase the system capacity is also conceivable. The form will be described below.
  • FIG. 12 is a diagram showing another embodiment of the radio base station of the present invention.
  • the present embodiment is a system composed of a radio base station 301-1 that covers the cell 302-1 as a communication area and a control device 201 for controlling the radio base station 301-1.
  • a radio base station 101 that covers the cell 102 as a communication area is added.
  • the radio base station 101 is also connected to the control device 201.
  • the cell 102 covered by the radio base station 101 and the cell 302-1 covered by the radio base station 301-1 are almost the same area.
  • the system capacity in the cell 102 (cell 302-1) can be substantially increased.
  • the control device 201 described above has been described as a host device of the radio base stations 101 and 301-1 to 301-3 that manage and control the radio base stations 101 and 301-1 to 301-3.
  • 301-1 to 301-3 may be a system (scheduling system) / function located in an upper network.
  • the above-described processing of the radio base station 101 may be performed by a logic circuit that is manufactured according to the purpose.
  • a program describing processing contents may be recorded on a recording medium readable by the radio base station 101, and the program recorded on the recording medium may be read by the radio base station 101 and executed.
  • the recording medium readable by the wireless base station 101 refers to a removable recording medium such as a floppy disk (registered trademark), a magneto-optical disk, a DVD, and a CD, as well as an HDD incorporated in the wireless base station 101.
  • the program recorded on the recording medium is read by a CPU (not shown) in the radio base station 101, and the same processing as described above is performed under the control of the CPU.
  • the CPU operates as a computer that executes a program read from a recording medium on which the program is recorded.

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Quality & Reliability (AREA)
  • Mobile Radio Communication Systems (AREA)
  • Time-Division Multiplex Systems (AREA)

Abstract

A wireless base station (101) which subjects a first time division duplex frame to transmission and reception using a predetermined wireless frequency band to and from a terminal having a wireless communication function. When receiving a second time division duplex frame transmitted from a wireless base station (301-1) using the wireless frequency band, the start timing of the transmission of the first time division duplex frame is set to be the timing with which the transmission never interferes with the second time division duplex frame, on the basis of the received second time division duplex frame. Thus, the first time division duplex frame is transmitted to the terminal with the set start timing.

Description

無線基地局、無線信号制御方法およびプログラムRadio base station, radio signal control method and program
　本発明は、無線通信を行うための無線基地局、無線信号制御方法およびプログラムに関し、特に時分割複信（ＴＤＤ）フレームを用いて無線通信を行うための無線基地局、無線信号制御方法およびプログラムに関する。 The present invention relates to a radio base station, a radio signal control method, and a program for performing radio communication, and more particularly to a radio base station, a radio signal control method, and a program for performing radio communication using a time division duplex (TDD) frame. About.
　近年、無線技術を用いた無線通信が急速に普及されてきている。一方、無線通信に使用できる周波数帯域は有限なものである。そのため、無線通信を行う端末等が増えるに従い、周波数帯域の枯渇が予想される。 In recent years, wireless communication using wireless technology has been rapidly spread. On the other hand, the frequency band that can be used for wireless communication is limited. Therefore, it is expected that the frequency band will be depleted as the number of terminals performing wireless communication increases.
　周波数帯域の枯渇が生じてしまうと、割り当て周波数が少ないシステム（例えば、ＷｉＭＡＸ技術を用いたシステム）においては、無線基地局において当該無線基地局とは異なる無線基地局にて使用されている周波数と同一の周波数を使わざるを得ない状況となってしまう。特に、時分割複信手法であるＴＤＤ（Ｔｉｍｅ　Ｄｉｖｉｓｉｏｎ　Ｄｕｐｌｅｘ）を用いて同期信号による送信タイミングが同期化されているシステムにおいて、互いに同一の周波数帯域を使用している複数の無線基地局が隣接している場合、互いの無線信号に干渉が生じてしまうおそれがある。これは、すでに配置されている無線基地局に対して、システム容量やカバレッジを増やすために新たに無線基地局を配置する場合にも同じ現象が生じてしまうおそれがある。 When the frequency band is depleted, in a system with a low allocated frequency (for example, a system using WiMAX technology), the frequency used in a radio base station different from the radio base station in the radio base station It becomes a situation where the same frequency must be used. In particular, in a system in which transmission timing by a synchronization signal is synchronized using TDD (Time Division Duplex), which is a time division duplex method, a plurality of radio base stations using the same frequency band are adjacent to each other. In such a case, there is a possibility that interference occurs between the radio signals. The same phenomenon may occur when a new radio base station is arranged in order to increase system capacity and coverage with respect to a radio base station already arranged.
　図１は、干渉が生じるおそれがある無線基地局と端末との配置の一例を示す図である。 FIG. 1 is a diagram illustrating an example of the arrangement of radio base stations and terminals that may cause interference.
　図１に示すように、無線基地局１００１－１と、無線基地局１００１－２とが配置されており、無線基地局１００１－１がカバーするセル１００２－１内に端末１００３－１が存在する。また、セル１００２－１と無線基地局１００１－２がカバーするセル１００２－２とが重なる部分に端末１００３－２が存在する。 As shown in FIG. 1, a radio base station 1001-1 and a radio base station 1001-2 are arranged, and a terminal 1003-1 exists in a cell 1002-1 covered by the radio base station 1001-1. . Further, the terminal 1003-2 exists in a portion where the cell 1002-1 and the cell 1002-2 covered by the radio base station 1001-2 overlap.
　このとき、端末１００３－２は無線基地局１００１－２と通信を行っている。しかしながら、セル１００２－１内にも存在しているため、端末１００３－２から無線基地局１００１－２へ送信された上り信号（端末１００３－２から無線基地局１００１－２への実線）が、無線基地局１００１－１にて干渉信号（端末１００３－２から無線基地局１００１－１への破線）として受信されてしまう。これにより、端末１００３－１から送信され、無線基地局１００１－１にて受信される上り信号に、当該干渉信号が影響を与えてしまうおそれがある。 At this time, the terminal 1003-2 is communicating with the radio base station 1001-2. However, since it also exists in the cell 1002-1, the uplink signal transmitted from the terminal 1003-2 to the radio base station 1001-2 (solid line from the terminal 1003-2 to the radio base station 1001-2) Radio base station 1001-1 receives the signal as an interference signal (broken line from terminal 1003-2 to radio base station 1001-1). As a result, the interference signal may affect the uplink signal transmitted from the terminal 1003-1 and received by the radio base station 1001-1.
　図２は、図１に示した配置において干渉するＴＤＤフレーム信号を示す図である。 FIG. 2 is a diagram showing TDD frame signals that interfere with each other in the arrangement shown in FIG.
　図２に示すように、端末１００３－２から送信される上り信号の送信タイミングと、無線基地局１００１－１にて受信される上り信号の受信タイミングとが一致する。そのため、端末１００３－２から送信される上り信号が、端末１００３－１から送信されて無線基地局１００１－１にて受信される上り信号に干渉してしまうおそれがある。 As shown in FIG. 2, the transmission timing of the uplink signal transmitted from the terminal 1003-2 matches the reception timing of the uplink signal received by the radio base station 1001-1. Therefore, the uplink signal transmitted from the terminal 1003-2 may interfere with the uplink signal transmitted from the terminal 1003-1 and received by the radio base station 1001-1.
　図３は、干渉が生じるおそれがある無線基地局と端末との配置の他の例を示す図である。 FIG. 3 is a diagram illustrating another example of the arrangement of radio base stations and terminals that may cause interference.
　図３に示すように、無線基地局１００１－１と、無線基地局１００１－２とが配置されており、無線基地局１００１－１がカバーするセル１００２－１と無線基地局１００１－２がカバーするセル１００２－２とが重なる部分に端末１００３－１が存在する。また、セル１００２－２内に端末１００３－２が存在する。 As shown in FIG. 3, a radio base station 1001-1 and a radio base station 1001-2 are arranged, and a cell 1002-1 and a radio base station 1001-2 covered by the radio base station 1001-1 are covered. The terminal 1003-1 exists in a portion where the cell 1002-2 to be overlapped. A terminal 1003-2 exists in the cell 1002-2.
　このとき、端末１００３－１は無線基地局１００１－１と通信を行っている。しかしながら、セル１００２－２内にも存在しているため、無線基地局１００１－２から端末１００３－２へ送信された下り信号（無線基地局１００１－２から端末１００３－２への実線）が、端末１００３－１にて干渉信号（無線基地局１００１－２から端末１００３－１への破線）として受信されてしまう。これにより、無線基地局１００１－１から送信され、端末１００３－１にて受信される下り信号に、当該干渉信号が影響を与えてしまうおそれがある。 At this time, the terminal 1003-1 is communicating with the radio base station 1001-1. However, since it also exists in the cell 1002-2, the downlink signal (solid line from the radio base station 1001-2 to the terminal 1003-2) transmitted from the radio base station 1001-2 to the terminal 1003-2 is Terminal 1003-1 receives the signal as an interference signal (broken line from radio base station 1001-2 to terminal 1003-1). As a result, the interference signal may affect a downlink signal transmitted from the radio base station 1001-1 and received by the terminal 1003-1.
　図４は、図３に示した配置において干渉するＴＤＤフレーム信号を示す図である。 FIG. 4 is a diagram showing TDD frame signals that interfere with each other in the arrangement shown in FIG.
　図４に示すように、無線基地局１００１－２から送信される下り信号の送信タイミングと、端末１００３－１にて受信される下り信号の受信タイミングとが一致する。そのため、無線基地局１００１－２から送信される下り信号が、無線基地局１００１－１から送信されて端末１００３－１にて受信される下り信号に干渉してしまうおそれがある。 As shown in FIG. 4, the transmission timing of the downlink signal transmitted from the radio base station 1001-2 matches the reception timing of the downlink signal received by the terminal 1003-1. Therefore, the downlink signal transmitted from the radio base station 1001-2 may interfere with the downlink signal transmitted from the radio base station 1001-1 and received by the terminal 1003-1.
　そこで、無線信号の送受信に指向性を持ったＢＦ（Beam　Forming）の技術を用いて、上述したような無線信号を回避する技術が考えられている。 Therefore, a technique for avoiding the above-described radio signal using a BF (Beam Forming) technique having directivity for transmission / reception of the radio signal is considered.
　また、無線基地局と端末との間にて無線通信が行われており、当該無線通信が、他の無線基地局と他の端末との間にて行われている無線通信に干渉する場合、信号を送信する周期を互いに異なる周期に変更することにより、当該干渉を軽減する技術が考えられている（例えば、特許公開２００３－２８９５７６号公報参照。）。 Further, when wireless communication is performed between the wireless base station and the terminal, and the wireless communication interferes with wireless communication performed between the other wireless base station and the other terminal, A technique for reducing the interference by changing signal transmission periods to different periods has been considered (see, for example, Japanese Patent Publication No. 2003-289576).
　しかしながら、ＢＦを用いた技術においては、無線基地局に設置するアンテナ素子数が増えてしまい、そのための設置コストが高くなってしまうという問題点がある。 However, in the technology using BF, there is a problem that the number of antenna elements to be installed in the radio base station increases, and the installation cost for that increases.
　また、特許公開２００３－２８９５７６号公報に記載された技術においては、一方の無線基地局と端末との間の信号送信周期を長く設定することにより、信号送信周期が長く設定された無線基地局と端末との間においては、通信速度が下がってしまうという問題点がある。 Further, in the technique described in Japanese Patent Publication No. 2003-289576, by setting a long signal transmission cycle between one radio base station and a terminal, a radio base station having a long signal transmission cycle and There is a problem in that the communication speed decreases with the terminal.
　本発明の目的は、上述した課題を解決する無線基地局、無線信号制御方法およびプログラムを提供することである。 An object of the present invention is to provide a radio base station, a radio signal control method, and a program that solve the above-described problems.
　上記目的を達成するために本発明は、
　無線通信機能を有する端末との間で、所定の無線周波数帯を用いて、第１の時分割複信フレームを送受信する無線基地局であって、
　前記無線周波数帯と同じ無線周波数帯を用いて、当該無線基地局以外の無線基地局から送信された第２の時分割複信フレームを受信した場合、前記受信した第２の時分割複信フレームに基づいて、前記第１の時分割複信フレームの送信の開始タイミングを、前記第２の時分割複信フレームに干渉しないタイミングに設定するタイミング設定部と、
　前記開始タイミングで前記第１の時分割複信フレームを前記端末へ送信する信号送信部とを有する。 In order to achieve the above object, the present invention provides:
A radio base station that transmits and receives a first time division duplex frame using a predetermined radio frequency band with a terminal having a radio communication function,
When a second time division duplex frame transmitted from a radio base station other than the radio base station is received using the same radio frequency band as the radio frequency band, the received second time division duplex frame is received. A timing setting unit that sets a start timing of transmission of the first time division duplex frame to a timing that does not interfere with the second time division duplex frame;
A signal transmission unit configured to transmit the first time division duplex frame to the terminal at the start timing.
　また、無線通信機能を有する端末と無線基地局との間で、所定の無線周波数帯を用いて送受信される第１の時分割複信フレームを制御する無線信号制御方法であって、
　前記無線周波数帯と同じ無線周波数帯を用いて、当該無線基地局以外の無線基地局から送信された第２の時分割複信フレームを当該無線基地局にて受信した場合、前記受信した第２の時分割複信フレームに基づいて、前記第１の時分割複信フレームの送信の開始タイミングを、前記第２の時分割複信フレームに干渉しないタイミングに設定するステップと、
　前記開始タイミングで前記第１の時分割複信フレームを当該無線基地局から前記端末へ送信するステップとを有する。 Further, a radio signal control method for controlling a first time division duplex frame transmitted and received using a predetermined radio frequency band between a terminal having a radio communication function and a radio base station,
When the second time division duplex frame transmitted from a radio base station other than the radio base station is received at the radio base station using the same radio frequency band as the radio frequency band, the received second Setting the start timing of transmission of the first time division duplex frame to a timing that does not interfere with the second time division duplex frame based on the time division duplex frame;
Transmitting the first time division duplex frame from the radio base station to the terminal at the start timing.
　また、無線通信機能を有する端末との間で、所定の無線周波数帯を用いて、第１の時分割複信フレームを送受信する無線基地局に実行させるためのプログラムであって、
　当該無線基地局にて、前記無線周波数帯と同じ無線周波数帯を用いて、当該無線基地局以外の無線基地局から送信された第２の時分割複信フレームを受信した場合、前記受信した第２の時分割複信フレームに基づいて、前記第１の時分割複信フレームの送信の開始タイミングを、前記第２の時分割複信フレームに干渉しないタイミングに設定する手順と、
　前記開始タイミングで前記第１の時分割複信フレームを前記端末へ送信する手順とを実行させる。 Further, a program for causing a radio base station to transmit and receive the first time division duplex frame using a predetermined radio frequency band with a terminal having a radio communication function,
In the radio base station, when the second time division duplex frame transmitted from a radio base station other than the radio base station is received using the same radio frequency band as the radio frequency band, the received first A procedure for setting the start timing of transmission of the first time division duplex frame to a timing that does not interfere with the second time division duplex frame based on two time division duplex frames;
Transmitting the first time division duplex frame to the terminal at the start timing.
　以上説明したように本発明においては、無線通信機能を有する端末との間で、所定の無線周波数帯を用いて、第１の時分割複信フレームを送受信する無線基地局において、第１の時分割複信フレームの送受信に用いる無線周波数帯と同じ無線周波数帯を用いて、当該無線基地局以外の無線基地局から送信された第２の時分割複信フレームを受信した場合、受信した第２の時分割複信フレームに基づいて、第１の時分割複信フレームの送信の開始タイミングを、第２の時分割複信フレームに干渉しないタイミングに設定し、設定した開始タイミングで第１の時分割複信フレームを端末へ送信する構成としたため、無線信号の干渉を容易に回避することができる。 As described above, in the present invention, in the radio base station that transmits and receives the first time division duplex frame using the predetermined radio frequency band with the terminal having the radio communication function, the first time When the second time division duplex frame transmitted from the radio base station other than the radio base station is received using the same radio frequency band as that used for transmission / reception of the division duplex frame, the received second time division duplex frame is received. Based on the time division duplex frame, the transmission start timing of the first time division duplex frame is set to a timing that does not interfere with the second time division duplex frame, and the first time is set at the set start timing. Since the divided duplex frame is transmitted to the terminal, radio signal interference can be easily avoided.
干渉が生じるおそれがある無線基地局と端末との配置の一例を示す図である。It is a figure which shows an example of arrangement | positioning with the radio base station and terminal which may generate interference. 図１に示した配置において干渉するＴＤＤフレーム信号を示す図である。It is a figure which shows the TDD frame signal which interferes in the arrangement | positioning shown in FIG. 干渉が生じるおそれがある無線基地局と端末との配置の他の例を示す図である。It is a figure which shows the other example of arrangement | positioning with the radio base station and terminal which may generate interference. 図３に示した配置において干渉するＴＤＤフレーム信号を示す図である。FIG. 4 is a diagram showing TDD frame signals that interfere in the arrangement shown in FIG. 3. 本発明の無線基地局の実施の一形態を示す図である。It is a figure which shows one Embodiment of the wireless base station of this invention. 図５に示した無線基地局の構成の一例を示す図である。It is a figure which shows an example of a structure of the wireless base station shown in FIG. 図５に示した形態における図６に示した無線基地局にて行われる無線信号制御方法の一例を説明するためのフローチャートである。7 is a flowchart for explaining an example of a radio signal control method performed in the radio base station shown in FIG. 6 in the form shown in FIG. 5. 無線基地局が受信するＴＤＤフレームの受信電力と時間との関係を示すグラフである。It is a graph which shows the relationship between the reception power and time of the TDD frame which a radio base station receives. 無線基地局から送信されるＴＤＤフレームと、そのスタートタイミングとの一例を示す図である。It is a figure which shows an example of the TDD frame transmitted from a wireless base station, and its start timing. 図５に示した形態における図６に示した無線基地局にて行われる無線信号制御方法の他の例を説明するためのフローチャートである。7 is a flowchart for explaining another example of the radio signal control method performed in the radio base station shown in FIG. 6 in the mode shown in FIG. 5. 図５に示した形態における図６に示した無線基地局にてＴＤＤフレームを解析することにより行われる無線信号制御方法の一例を説明するためのフローチャートである。7 is a flowchart for explaining an example of a radio signal control method performed by analyzing a TDD frame in the radio base station shown in FIG. 6 in the form shown in FIG. 5. 本発明の無線基地局の実施の他の形態を示す図である。It is a figure which shows the other form of implementation of the wireless base station of this invention.
　以下に、本発明の実施の形態について図面を参照して説明する。 Hereinafter, embodiments of the present invention will be described with reference to the drawings.
　図５は、本発明の無線基地局の実施の一形態を示す図である。 FIG. 5 is a diagram showing an embodiment of the radio base station of the present invention.
　本形態は図５に示すように、セル３０２－１～３０２－３をそれぞれ通信エリアとしてカバーする無線基地局３０１－１～３０１－３と、無線基地局３０１－１～３０１－３の上位装置であり、無線基地局３０１－１～３０１－３を制御するための制御装置２０１とから構成されているシステムにおいて、セル１０２を通信エリアとしてカバーする無線基地局１０１が追加されている。無線基地局１０１もまた制御装置２０１と接続されている。また、無線基地局１０１がカバーするセル１０２と、無線基地局３０１－１～３０１－３がそれぞれカバーするセル３０２－１～３０２－３とは、重なった部分を有している。なお、図５に示した無線基地局１０１，３０１－１～３０２－３は、一般的な無線通信機能を有する端末と無線通信を行うことにより接続される無線基地局である。 In this embodiment, as shown in FIG. 5, radio base stations 301-1 to 301-3 that cover cells 302-1 to 302-3 as communication areas, and higher-level devices of the radio base stations 301-1 to 301-3, respectively. In the system configured with the control device 201 for controlling the radio base stations 301-1 to 301-3, a radio base station 101 that covers the cell 102 as a communication area is added. The radio base station 101 is also connected to the control device 201. Further, the cell 102 covered by the radio base station 101 and the cells 302-1 through 302-3 covered by the radio base stations 301-1 through 301-3 respectively have overlapping portions. Note that the radio base stations 101 and 301-1 to 302-3 shown in FIG. 5 are radio base stations connected by performing radio communication with a terminal having a general radio communication function.
　図６は、図５に示した無線基地局１０１の構成の一例を示す図である。 FIG. 6 is a diagram illustrating an example of the configuration of the radio base station 101 illustrated in FIG.
　図５に示した無線基地局１０１には図６に示すように、信号受信部１１１と、受信電力測定部１１２と、タイミング設定部１１３と、記憶部１１４と、信号送信部１１５とが設けられている。 As illustrated in FIG. 6, the radio base station 101 illustrated in FIG. 5 includes a signal reception unit 111, a reception power measurement unit 112, a timing setting unit 113, a storage unit 114, and a signal transmission unit 115. ing.
　信号受信部１１１は、隣接する無線基地局３０１－１～３０１－３から送信された信号である時分割複信フレーム（以下、ＴＤＤフレームと称する）を受信する。 The signal receiving unit 111 receives time division duplex frames (hereinafter referred to as TDD frames) that are signals transmitted from the adjacent radio base stations 301-1 to 301-3.
　受信電力測定部１１２は、信号受信部１１１にて受信されたＴＤＤフレームの受信電力を測定する。 The received power measuring unit 112 measures the received power of the TDD frame received by the signal receiving unit 111.
　タイミング設定部１１３は、受信電力測定部１１２にて測定された結果に基づいて、無線基地局１０１に接続される端末へ送信するＴＤＤフレームの送信タイミングを設定する。 The timing setting unit 113 sets the transmission timing of the TDD frame to be transmitted to the terminal connected to the radio base station 101 based on the result measured by the received power measuring unit 112.
　記憶部１１４は、タイミング設定部１１３で設定された送信タイミング等を記憶する。また、後述する閾値を記憶しても良い。 The storage unit 114 stores the transmission timing set by the timing setting unit 113. Moreover, you may memorize | store the threshold value mentioned later.
　信号送信部１１５は、タイミング設定部１１３にて設定された送信タイミングで、ＴＤＤフレームを端末へ送信する。 The signal transmission unit 115 transmits the TDD frame to the terminal at the transmission timing set by the timing setting unit 113.
　なお、図６には、図５に示した無線基地局１０１の構成要素のうち、本発明に関わる構成要素のみを示した。 FIG. 6 shows only the components related to the present invention among the components of the radio base station 101 shown in FIG.
　以下に、図５に示した形態における図６に示した無線基地局１０１にて行われる無線信号制御方法について説明する。なお、無線基地局１０１が隣接する無線基地局３０１－１～３０１－３のうち、無線基地局３０１－１が、無線基地局１０１において測定された受信電力の最も高いＴＤＤフレームを送信した無線基地局である場合を例に挙げて説明する。 Hereinafter, the radio signal control method performed by the radio base station 101 shown in FIG. 6 in the form shown in FIG. 5 will be described. Of the radio base stations 301-1 to 301-3 adjacent to the radio base station 101, the radio base station 301-1 transmits the TDD frame having the highest received power measured at the radio base station 101. A case of a station will be described as an example.
　図７は、図５に示した形態における図６に示した無線基地局１０１にて行われる無線信号制御方法の一例を説明するためのフローチャートである。 FIG. 7 is a flowchart for explaining an example of the radio signal control method performed by the radio base station 101 shown in FIG. 6 in the form shown in FIG.
　まず、無線基地局３０１－１から送信された第２の時分割複信フレームであるＴＤＤフレームが、ステップ１にて信号受信部１１１において受信されることにより、モニタされる。 First, the TDD frame, which is the second time division duplex frame transmitted from the radio base station 301-1, is monitored by being received by the signal receiving unit 111 in step 1.
　すると、信号受信部１１１にてモニタされたＴＤＤフレームの受信電力がステップ２にて受信電力測定部１１２において測定される。この測定方法については、一般的に用いられている方法で良い。測定された受信電力は、受信電力情報として受信電力測定部１１２からタイミング設定部１１３へ出力される。 Then, the received power of the TDD frame monitored by the signal receiving unit 111 is measured by the received power measuring unit 112 in step 2. About this measuring method, the method generally used may be used. The measured received power is output from the received power measuring unit 112 to the timing setting unit 113 as received power information.
　続いて、受信電力測定部１１２から出力された受信電力情報がタイミング設定部１１３に入力すると、入力した受信電力情報に基づいて無線基地局１０１から無線基地局１０１と接続された端末へ第１の時分割複信フレームであるＴＤＤフレームを送信するタイミングがタイミング設定部１１３にて設定される。 Subsequently, when the received power information output from the received power measuring unit 112 is input to the timing setting unit 113, a first connection is made from the radio base station 101 to a terminal connected to the radio base station 101 based on the input received power information. The timing setting unit 113 sets the timing for transmitting a TDD frame that is a time division duplex frame.
　具体的には、受信電力の最も低い時刻（タイミング）がＴＤＤフレームの送信開始のタイミングを意味するスタートタイミングにステップ３にて設定される。これは、無線基地局３０１－１から送信されるＴＤＤフレームが無線基地局１０１にて受信されるときの受信電力が最も低いときが、信号の干渉が生じる確率が最も低いと判断するものである。 Specifically, the time (timing) with the lowest received power is set in step 3 to the start timing that means the timing for starting transmission of the TDD frame. This is to determine that the probability of signal interference is the lowest when the reception power when the TDD frame transmitted from the radio base station 301-1 is received by the radio base station 101 is the lowest. .
　なお、第１の時分割複信フレームを送受信するために用いる無線周波数帯と、第２の時分割複信フレームを送受信するために用いる無線周波数帯とは、同じ無線周波数帯である。 Note that the radio frequency band used for transmitting / receiving the first time division duplex frame and the radio frequency band used for transmitting / receiving the second time division duplex frame are the same radio frequency band.
　図８は、無線基地局１０１が受信するＴＤＤフレームの受信電力と時間との関係を示すグラフである。縦軸に受信電力を示しており、また横軸に時間を示している。また、ここでは、ＷｉＭＡＸシステムのように、ＴＤＤフレームが５ｍｓの周期を持った（５ｍｓの長さの）フレーム単位で送受信される場合を例に挙げる。 FIG. 8 is a graph showing the relationship between the reception power of the TDD frame received by the radio base station 101 and time. The vertical axis represents received power, and the horizontal axis represents time. Here, a case where a TDD frame is transmitted / received in a frame unit (having a length of 5 ms) having a period of 5 ms as in the WiMAX system will be described as an example.
　図８に示すように、受信電力が時間と共に変化しており、受信電力の最も低い時刻がフレーム周期で現れる。この受信電力の最も低い時刻が、スタート（開始）タイミングとして設定される。 As shown in FIG. 8, the received power changes with time, and the lowest received power time appears in the frame period. The time at which the received power is lowest is set as the start timing.
　図９は、無線基地局１０１，３０１－１から送信されるＴＤＤフレームと、そのスタートタイミングとの一例を示す図である。ここでは、ＷｉＭＡＸシステムにおけるものを例に挙げて説明する。 FIG. 9 is a diagram showing an example of TDD frames transmitted from the radio base stations 101 and 301-1 and their start timings. Here, an example in the WiMAX system will be described.
　図９に示すように、無線基地局１０１，３０１－１から送信されるＴＤＤフレームには、端末の初期同期、伝送路決定、無線基地局１０１，３０１－１の識別（無線基地局識別情報）に用いられるＰｉｌｏｔ信号であるＰｒｅａｍｂｌｅ信号が先頭に存在している。また、Ｐｒｅａｍｂｌｅ信号に続いて、無線基地局１０１，３０１－１から端末へ送信される情報である下り信号が格納される下り信号のサブフレーム（以下、下り信号サブフレームと称する）が存在する。さらに、下り信号サブフレームに続いて、端末から無線基地局１０１，３０１－１へ送信される上り信号が格納される上り信号のサブフレーム（以下、上り信号サブフレームと称する）が存在する。また、上り信号サブフレームと下り信号サブフレームとの間に、無線基地局１０１，３０１－１と端末との間の伝搬遅延を吸収するためのＧａｐ時間であるＴＴＧが設けられている。また、同様のＧａｐ時間であるＲＴＧが上り信号サブフレームに続いて設けられている。 As shown in FIG. 9, in the TDD frame transmitted from the radio base stations 101 and 301-1, initial synchronization of terminals, transmission path determination, identification of the radio base stations 101 and 301-1 (radio base station identification information) A preamble signal which is a pilot signal used for the first is present at the head. Subsequent to the preamble signal, there is a downlink signal subframe (hereinafter referred to as a downlink signal subframe) in which a downlink signal, which is information transmitted from the radio base stations 101 and 301-1, is stored. Further, following the downlink signal subframe, there is an uplink signal subframe (hereinafter referred to as an uplink signal subframe) in which an uplink signal transmitted from the terminal to the radio base stations 101 and 301-1 is stored. Further, a TTG that is a gap time for absorbing a propagation delay between the radio base stations 101 and 301-1 and the terminal is provided between the uplink signal subframe and the downlink signal subframe. Further, RTG having the same gap time is provided subsequent to the uplink signal subframe.
　ここで、ＴＤＤフレームの下り信号サブフレームが下り信号（ユーザバースト信号）で埋まっている場合、図８に示した受信電力の最も低い時刻は、図９に示した無線基地局３０１－１から送信されるＴＤＤフレームの下り信号サブフレームの送信完了時刻に当たる可能性が高い。それは、無線基地局３０１－１から端末へ送信されるユーザバースト信号の受信電力が高いため、その下り信号の送信が完了した時刻が受信電力の最も低い時刻となるためである。このユーザバースト信号とは、無線基地局１０１，３０１－１～３０１－３から端末へ送信される下り信号であり、下り信号サブフレーム内で送信される。 Here, when the downlink signal subframe of the TDD frame is filled with the downlink signal (user burst signal), the lowest reception power time shown in FIG. 8 is transmitted from the radio base station 301-1 shown in FIG. There is a high possibility that it will be the transmission completion time of the downlink signal subframe of the TDD frame to be transmitted. This is because the reception power of the user burst signal transmitted from the radio base station 301-1 to the terminal is high, and the time when the transmission of the downlink signal is completed becomes the time with the lowest reception power. This user burst signal is a downlink signal transmitted from the radio base stations 101, 301-1 to 301-3 to the terminal, and is transmitted in a downlink signal subframe.
　これにより、ＴＤＤフレームの下り信号サブフレームがユーザバースト信号で埋まっている場合、無線基地局１０１から端末へ送信されるＴＤＤフレームのスタートタイミングは図９に示すように、無線基地局３０１－１から送信されるＴＤＤフレームの下り信号サブフレームの送信完了時刻になる可能性が高い。 Thereby, when the downlink signal subframe of the TDD frame is filled with the user burst signal, the start timing of the TDD frame transmitted from the radio base station 101 to the terminal is transmitted from the radio base station 301-1 as shown in FIG. There is a high possibility that it will be the transmission completion time of the downlink signal subframe of the TDD frame to be transmitted.
　このようにステップ３においてタイミング設定部１１３にて設定されたスタートタイミングで、ステップ４にて信号送信部１１５からＴＤＤフレームが端末へ送信される。 Thus, at the start timing set by the timing setting unit 113 in step 3, the TDD frame is transmitted from the signal transmission unit 115 to the terminal in step 4.
　また、図６に示した記憶部１１４に所定の閾値を予め記憶しておき、記憶された閾値と受信電力との比較結果に基づいてスタートタイミングが設定されるものであっても良い。 Alternatively, a predetermined threshold value may be stored in advance in the storage unit 114 illustrated in FIG. 6, and the start timing may be set based on a comparison result between the stored threshold value and the received power.
　図１０は、図５に示した形態における図６に示した無線基地局１０１にて行われる無線信号制御方法の他の例を説明するためのフローチャートである。 FIG. 10 is a flowchart for explaining another example of the radio signal control method performed in the radio base station 101 shown in FIG. 6 in the form shown in FIG.
　まず、無線基地局３０１－１から送信されたＴＤＤフレームが、ステップ１１にて信号受信部１１１において受信されることにより、モニタされる。 First, the TDD frame transmitted from the radio base station 301-1 is monitored by being received by the signal receiving unit 111 in step 11.
　すると、信号受信部１１１にてモニタされたＴＤＤフレームの受信電力がステップ１２にて受信電力測定部１１２において測定される。この測定方法については、一般的に用いられている方法で良い。測定された受信電力は、受信電力情報として受信電力測定部１１２からタイミング設定部１１３へ出力される。 Then, the received power of the TDD frame monitored by the signal receiving unit 111 is measured by the received power measuring unit 112 in step 12. About this measuring method, the method generally used may be used. The measured received power is output from the received power measuring unit 112 to the timing setting unit 113 as received power information.
　続いて、受信電力測定部１１２から出力された受信電力情報がタイミング設定部１１３に入力すると、記憶部１１４に予め記憶されている閾値がタイミング設定部１１３によって読み出される。そして、記憶部１１４から読み出された閾値と、タイミング設定部１１３に入力した受信電力情報に示される受信電力とがステップ１３にて比較される。 Subsequently, when the received power information output from the received power measuring unit 112 is input to the timing setting unit 113, the threshold value stored in advance in the storage unit 114 is read by the timing setting unit 113. Then, the threshold read from the storage unit 114 and the received power indicated by the received power information input to the timing setting unit 113 are compared in step 13.
　ここで、記憶部１１４に記憶されている閾値は、無線基地局１０１から端末へ送信される信号に干渉を及ぼさない他の信号の受信電力の値が予め計算されて設定されたものである。 Here, the threshold value stored in the storage unit 114 is set by calculating in advance the value of the received power of another signal that does not interfere with the signal transmitted from the radio base station 101 to the terminal.
　その後、比較の結果に基づいて無線基地局１０１から無線基地局１０１と接続された端末へＴＤＤフレームを送信するタイミングがタイミング設定部１１３にて設定される。 Thereafter, the timing setting unit 113 sets the timing for transmitting the TDD frame from the radio base station 101 to the terminal connected to the radio base station 101 based on the comparison result.
　具体的には、受信電力が閾値よりも低い時刻がスタートタイミングにステップ１４にて設定される。これは、無線基地局３０１－１から送信されるＴＤＤフレームが無線基地局１０１にて受信されるときの受信電力が閾値よりも低いときが、信号の干渉が生じる確率が低いと判断するものである。 More specifically, the time when the received power is lower than the threshold is set as the start timing in step 14. This is because when the TDD frame transmitted from the radio base station 301-1 is received by the radio base station 101, the probability that signal interference will occur is low when the received power is lower than the threshold. is there.
　このようにタイミング設定部１１３にて設定されたスタートタイミングで、ステップ１５にて信号送信部１１５からＴＤＤフレームが端末へ送信される。 The TDD frame is transmitted from the signal transmission unit 115 to the terminal in step 15 at the start timing set by the timing setting unit 113 in this way.
　また、信号受信部１１１にて受信されたＴＤＤフレームをタイミング設定部１１３にて解析することにより、スタートタイミングが設定されるものであっても良い。このとき、受信電力測定部１１２における受信電力の測定は行われない。 Further, the start timing may be set by analyzing the TDD frame received by the signal receiving unit 111 by the timing setting unit 113. At this time, the reception power measurement unit 112 does not measure the reception power.
　図１１は、図５に示した形態における図６に示した無線基地局１０１にてＴＤＤフレームを解析することにより行われる無線信号制御方法の一例を説明するためのフローチャートである。 FIG. 11 is a flowchart for explaining an example of a radio signal control method performed by analyzing the TDD frame in the radio base station 101 shown in FIG. 6 in the form shown in FIG.
　まず、無線基地局３０１－１から送信されたＴＤＤフレームが、ステップ３１にて信号受信部１１１において受信されると、受信されたＴＤＤフレームがステップ３２にてタイミング設定部１１３において解析される。 First, when the TDD frame transmitted from the radio base station 301-1 is received by the signal receiving unit 111 in step 31, the received TDD frame is analyzed in the timing setting unit 113 in step 32.
　ＴＤＤフレーム内のサブフレーム構造およびトラフィック情報を示すＭＡＰ情報が解析されることにより、当該ＴＤＤフレーム内の下りサブフレームの構造を把握することができる。ＭＡＰ情報は、下り信号サブフレームの先頭に格納されており、上り信号や下り信号（ユーザバースト信号）がフレーム内でどのようにマッピングされているかを示す情報である。そして、ＭＡＰ情報に示された下り信号に基づいて、無線基地局１０１から端末へ送信されるＴＤＤフレームのスタートタイミングがステップ３３にて設定される。具体的には、無線基地局３０１－１から送信されるＴＤＤフレームの下り信号サブフレーム内の下り信号（ユーザバースト信号）の送信完了時刻に設定される。 By analyzing the subframe structure in the TDD frame and the MAP information indicating the traffic information, the structure of the downlink subframe in the TDD frame can be grasped. The MAP information is stored at the head of the downlink signal subframe, and is information indicating how uplink signals and downlink signals (user burst signals) are mapped in the frame. Then, based on the downlink signal indicated in the MAP information, the start timing of the TDD frame transmitted from the radio base station 101 to the terminal is set in step 33. Specifically, it is set to the transmission completion time of the downlink signal (user burst signal) in the downlink signal subframe of the TDD frame transmitted from the radio base station 301-1.
　このようにタイミング設定部１１３にて設定されたスタートタイミングで、ステップ３４にて信号送信部１１５からＴＤＤフレームが端末へ送信される。 The TDD frame is transmitted from the signal transmission unit 115 to the terminal in step 34 at the start timing set by the timing setting unit 113 in this way.
　また、上述した形態は、カバレッジを増やすために無線基地局１０１が追加された形態である。一方、システム容量を増やすために無線基地局１０１が追加された形態も考えられる。その形態について、以下に説明する。 Further, the above-described form is a form in which the radio base station 101 is added to increase the coverage. On the other hand, a mode in which the radio base station 101 is added to increase the system capacity is also conceivable. The form will be described below.
　図１２は、本発明の無線基地局の実施の他の形態を示す図である。 FIG. 12 is a diagram showing another embodiment of the radio base station of the present invention.
　本形態は図１２に示すように、セル３０２－１を通信エリアとしてカバーする無線基地局３０１－１と、無線基地局３０１－１を制御するための制御装置２０１とから構成されているシステムにおいて、セル１０２を通信エリアとしてカバーする無線基地局１０１が追加されている。無線基地局１０１もまた制御装置２０１と接続されている。また、無線基地局１０１がカバーするセル１０２と、無線基地局３０１－１カバーするセル３０２－１とは、ほぼ同一のエリアとなっている。 As shown in FIG. 12, the present embodiment is a system composed of a radio base station 301-1 that covers the cell 302-1 as a communication area and a control device 201 for controlling the radio base station 301-1. A radio base station 101 that covers the cell 102 as a communication area is added. The radio base station 101 is also connected to the control device 201. The cell 102 covered by the radio base station 101 and the cell 302-1 covered by the radio base station 301-1 are almost the same area.
　図１２に示すような形態をとることにより、セル１０２（セル３０２－１）内のシステム容量を実質的に増やすことができる。 By taking the form as shown in FIG. 12, the system capacity in the cell 102 (cell 302-1) can be substantially increased.
　なお、上述した制御装置２０１は、無線基地局１０１，３０１－１～３０１－３を管理および制御する無線基地局１０１，３０１－１～３０１－３の上位装置として説明したが、無線基地局１０１，３０１－１～３０１－３の上位ネットワークに位置するシステム（スケジューリングシステム）・機能であっても良い。 The control device 201 described above has been described as a host device of the radio base stations 101 and 301-1 to 301-3 that manage and control the radio base stations 101 and 301-1 to 301-3. , 301-1 to 301-3 may be a system (scheduling system) / function located in an upper network.
　また、上述した無線基地局１０１の処理は、目的に応じて作製された論理回路で行うようにしても良い。また、処理内容を記述したプログラムを無線基地局１０１にて読取可能な記録媒体に記録し、この記録媒体に記録されたプログラムを無線基地局１０１に読み込ませ、実行するものであっても良い。無線基地局１０１にて読取可能な記録媒体とは、フロッピーディスク（登録商標）、光磁気ディスク、ＤＶＤ、ＣＤなどの移設可能な記録媒体の他、無線基地局１０１に内蔵されたＨＤＤ等を指す。この記録媒体に記録されたプログラムは、無線基地局１０１内のＣＰＵ（不図示）にて読み込まれ、ＣＰＵの制御によって、上述したものと同様の処理が行われる。ここで、ＣＰＵは、プログラムが記録された記録媒体から読み込まれたプログラムを実行するコンピュータとして動作するものである。 Further, the above-described processing of the radio base station 101 may be performed by a logic circuit that is manufactured according to the purpose. Alternatively, a program describing processing contents may be recorded on a recording medium readable by the radio base station 101, and the program recorded on the recording medium may be read by the radio base station 101 and executed. The recording medium readable by the wireless base station 101 refers to a removable recording medium such as a floppy disk (registered trademark), a magneto-optical disk, a DVD, and a CD, as well as an HDD incorporated in the wireless base station 101. . The program recorded on the recording medium is read by a CPU (not shown) in the radio base station 101, and the same processing as described above is performed under the control of the CPU. Here, the CPU operates as a computer that executes a program read from a recording medium on which the program is recorded.
　以上、実施の形態を参照して本願発明を説明したが、本願発明は上記実施の形態に限定されるものではない。本願発明の構成や詳細には、本願発明のスコープ内で当業者が理解し得る様々な変更をすることができる。 The present invention has been described above with reference to the embodiments, but the present invention is not limited to the above embodiments. Various changes that can be understood by those skilled in the art can be made to the configuration and details of the present invention within the scope of the present invention.
　この出願は、２００８年３月２８日に出願された日本出願特願２００８－０８６５８８を基礎とする優先権を主張し、その開示の全てをここに取り込む。 This application claims priority based on Japanese Patent Application No. 2008-086588 filed on Mar. 28, 2008, the entire disclosure of which is incorporated herein.

Claims (21)

  1. 　無線通信機能を有する端末との間で、所定の無線周波数帯を用いて、第１の時分割複信フレームを送受信する無線基地局であって、
    　前記無線周波数帯と同じ無線周波数帯を用いて、当該無線基地局以外の無線基地局から送信された第２の時分割複信フレームを受信した場合、前記受信した第２の時分割複信フレームに基づいて、前記第１の時分割複信フレームの送信の開始タイミングを、前記第２の時分割複信フレームに干渉しないタイミングに設定するタイミング設定部と、
    　前記開始タイミングで前記第１の時分割複信フレームを前記端末へ送信する信号送信部とを有する無線基地局。     A radio base station that transmits and receives a first time division duplex frame using a predetermined radio frequency band with a terminal having a radio communication function,
    When a second time division duplex frame transmitted from a radio base station other than the radio base station is received using the same radio frequency band as the radio frequency band, the received second time division duplex frame is received. A timing setting unit that sets a start timing of transmission of the first time division duplex frame to a timing that does not interfere with the second time division duplex frame;
    A radio base station comprising: a signal transmission unit that transmits the first time division duplex frame to the terminal at the start timing.
  2. 　請求項１に記載の無線基地局において、
    　前記タイミング設定部は、前記第２の時分割複信フレームの構造を該第２の時分割複信フレームに格納されたＭＡＰ情報に基づいて解析し、該第２の時分割複信フレーム内の下り信号の送信完了時刻を前記開始タイミングに設定することを特徴とする無線基地局。     In the radio base station according to claim 1,
    The timing setting unit analyzes the structure of the second time division duplex frame based on the MAP information stored in the second time division duplex frame, and stores the second time division duplex frame in the second time division duplex frame. A radio base station, wherein a downlink signal transmission completion time is set to the start timing.
  3. 　請求項１に記載の無線基地局において、
    　前記受信した第２の時分割複信フレームの受信電力を測定する受信電力測定部を有し、
    　前記タイミング設定部は、前記受信電力測定部が測定した受信電力に基づいて、前記開始タイミングを設定することを特徴とする無線基地局。     In the radio base station according to claim 1,
    A received power measuring unit for measuring received power of the received second time division duplex frame;
    The radio base station, wherein the timing setting unit sets the start timing based on the reception power measured by the reception power measurement unit.
  4. 　請求項３に記載の無線基地局において、
    　当該該無線周波数帯を用いる、当該無線基地局以外の複数の無線基地局から送信された第２の時分割複信フレームを受信した場合、前記受信電力測定部は、前記複数の無線基地局のうち前記受信電力が最も高い第２の時分割複信フレームを送信した無線基地局から送信された前記第２の時分割複信フレームの受信電力を測定することを特徴とする無線基地局。     In the radio base station according to claim 3,
    When the second time division duplex frame transmitted from a plurality of radio base stations other than the radio base station using the radio frequency band is received, the received power measurement unit is configured to receive the plurality of radio base stations. A radio base station that measures the received power of the second time division duplex frame transmitted from the radio base station that has transmitted the second time division duplex frame having the highest received power.
  5. 　請求項３または請求項４に記載の無線基地局において、
    　前記タイミング設定部は、前記受信電力測定部が測定した受信電力の最も低い時刻を前記開始タイミングに設定することを特徴とする無線基地局。     In the radio base station according to claim 3 or 4,
    The radio base station, wherein the timing setting unit sets a time at which the received power measured by the received power measuring unit is lowest as the start timing.
  6. 　請求項３または請求項４に記載の無線基地局において、
    　前記タイミング設定部は、前記受信電力測定部が測定した受信電力と所定の閾値とに基づいて、前記開始タイミングを設定することを特徴とする無線基地局。     In the radio base station according to claim 3 or 4,
    The radio base station, wherein the timing setting unit sets the start timing based on the reception power measured by the reception power measurement unit and a predetermined threshold.
  7. 　請求項６に記載の無線基地局において、
    　前記タイミング設定部は、前記受信電力測定部が測定した受信電力が前記閾値よりも低い時刻を前記開始タイミングに設定することを特徴とする無線基地局。     The radio base station according to claim 6,
    The radio base station, wherein the timing setting unit sets a time at which the received power measured by the received power measuring unit is lower than the threshold as the start timing.
  8. 　無線通信機能を有する端末と無線基地局との間で、所定の無線周波数帯を用いて送受信される第１の時分割複信フレームを制御する無線信号制御方法であって、
    　前記無線周波数帯と同じ無線周波数帯を用いて、当該無線基地局以外の無線基地局から送信された第２の時分割複信フレームを当該無線基地局にて受信した場合、前記受信した第２の時分割複信フレームに基づいて、前記第１の時分割複信フレームの送信の開始タイミングを、前記第２の時分割複信フレームに干渉しないタイミングに設定するステップと、
    　前記開始タイミングで前記第１の時分割複信フレームを当該無線基地局から前記端末へ送信するステップとを有する無線信号制御方法。     A radio signal control method for controlling a first time division duplex frame transmitted / received between a terminal having a radio communication function and a radio base station using a predetermined radio frequency band,
    When the second time division duplex frame transmitted from a radio base station other than the radio base station is received at the radio base station using the same radio frequency band as the radio frequency band, the received second Setting the start timing of transmission of the first time division duplex frame to a timing that does not interfere with the second time division duplex frame based on the time division duplex frame;
    A radio signal control method comprising: transmitting the first time division duplex frame from the radio base station to the terminal at the start timing.
  9. 　請求項８に記載の無線信号制御方法において、
    　前記第２の時分割複信フレームの構造を該第２の時分割複信フレームに格納されたＭＡＰ情報に基づいて解析するステップと、
    　前記第２の時分割複信フレーム内の下り信号の送信完了時刻を前記開始タイミングに設定するステップとを有することを特徴とする無線信号制御方法。     The radio signal control method according to claim 8,
    Analyzing the structure of the second time division duplex frame based on MAP information stored in the second time division duplex frame;
    And a step of setting a transmission completion time of a downlink signal in the second time division duplex frame as the start timing.
  10. 　請求項８に記載の無線信号制御方法において、
    　前記受信した第２の時分割複信フレームの受信電力を測定するステップと、
    　前記測定した受信電力に基づいて、前記開始タイミングを設定するステップとを有することを特徴とする無線信号制御方法。     The radio signal control method according to claim 8,
    Measuring the received power of the received second time division duplex frame;
    And a step of setting the start timing based on the measured received power.
  11. 　請求項１０に記載の無線信号制御方法において、
    　当該無線周波数帯を用いる、当該無線基地局以外の複数の無線基地局から送信された第２の時分割複信フレームを当該無線基地局にて受信した場合、前記複数の無線基地局のうち前記受信電力が最も高い第２の時分割複信フレームを送信した無線基地局から送信された前記第２の時分割複信フレームの受信電力を測定するステップを有することを特徴とする無線信号制御方法。     The radio signal control method according to claim 10, wherein
    When receiving the second time division duplex frame transmitted from a plurality of radio base stations other than the radio base station using the radio frequency band, the radio base station, A radio signal control method comprising a step of measuring the reception power of the second time division duplex frame transmitted from the radio base station that has transmitted the second time division duplex frame having the highest reception power. .
  12. 　請求項１０または請求項１１に記載の無線信号制御方法において、
    　前記測定した受信電力の最も低い時刻を前記開始タイミングに設定するステップを有することを特徴とする無線信号制御方法。     The radio signal control method according to claim 10 or 11,
    A radio signal control method comprising: setting the time when the measured received power is lowest as the start timing.
  13. 　請求項１０または請求項１１に記載の無線信号制御方法において、
    　前記測定した受信電力と所定の閾値とに基づいて、前記開始タイミングを設定するステップを有することを特徴とする無線信号制御方法。     The radio signal control method according to claim 10 or 11,
    A radio signal control method comprising: setting the start timing based on the measured received power and a predetermined threshold value.
  14. 　請求項１３に記載の無線信号制御方法において、
    　前記測定した受信電力が前記閾値よりも低い時刻を前記開始タイミングに設定するステップを有することを特徴とする無線信号制御方法。     The radio signal control method according to claim 13,
    A radio signal control method comprising: setting a time at which the measured received power is lower than the threshold as the start timing.
  15. 　無線通信機能を有する端末との間で、所定の無線周波数帯を用いて、第１の時分割複信フレームを送受信する無線基地局に、
    　当該無線基地局にて、前記無線周波数帯と同じ無線周波数帯を用いて、当該無線基地局以外の無線基地局から送信された第２の時分割複信フレームを受信した場合、前記受信した第２の時分割複信フレームに基づいて、前記第１の時分割複信フレームの送信の開始タイミングを、前記第２の時分割複信フレームに干渉しないタイミングに設定する手順と、
    　前記開始タイミングで前記第１の時分割複信フレームを前記端末へ送信する手順とを実行させるためのプログラム。     A radio base station that transmits and receives a first time division duplex frame using a predetermined radio frequency band with a terminal having a radio communication function,
    In the radio base station, when the second time division duplex frame transmitted from a radio base station other than the radio base station is received using the same radio frequency band as the radio frequency band, the received first A procedure for setting the start timing of transmission of the first time division duplex frame to a timing that does not interfere with the second time division duplex frame based on two time division duplex frames;
    A program for executing the procedure for transmitting the first time division duplex frame to the terminal at the start timing.
  16. 　請求項１５に記載のプログラムにおいて、
    　前記第２の時分割複信フレームの構造を該第２の時分割複信フレームに格納されたＭＡＰ情報に基づいて解析する手順と、
    　前記第２の時分割複信フレーム内の下り信号の送信完了時刻を前記開始タイミングに設定する手順とを実行させるためのプログラム。     The program according to claim 15, wherein
    Analyzing the structure of the second time division duplex frame based on MAP information stored in the second time division duplex frame;
    A program for executing a procedure for setting a transmission completion time of a downlink signal in the second time division duplex frame as the start timing.
  17. 　請求項１５に記載のプログラムにおいて、
    　前記受信した第２の時分割複信フレームの受信電力を測定する手順と、
    　前記測定した受信電力に基づいて、前記開始タイミングを設定する手順とを実行させるためのプログラム。     The program according to claim 15, wherein
    Measuring the received power of the received second time division duplex frame;
    A program for executing a procedure for setting the start timing based on the measured received power.
  18. 　請求項１７に記載のプログラムにおいて、
    　当該無線基地局にて、当該無線周波数帯を用いる、当該無線基地局以外の複数の無線基地局から送信された第２の時分割複信フレームを受信した場合、
    　前記複数の無線基地局のうち前記受信電力が最も高い第２の時分割複信フレームを送信した無線基地局から送信された前記第２の時分割複信フレームの受信電力を測定する手順を実行させるためのプログラム。     The program according to claim 17, wherein
    When receiving the second time division duplex frame transmitted from a plurality of radio base stations other than the radio base station using the radio frequency band in the radio base station,
    Executing a procedure of measuring the received power of the second time division duplex frame transmitted from the radio base station that has transmitted the second time division duplex frame having the highest received power among the plurality of radio base stations; Program to let you.
  19. 　請求項１７または請求項１８に記載のプログラムにおいて、
    　前記測定した受信電力の最も低い時刻を前記開始タイミングに設定する手順を実行させるためのプログラム。     In the program according to claim 17 or 18,
    A program for executing a procedure for setting the lowest time of the measured received power as the start timing.
  20. 　請求項１７または請求項１８に記載のプログラムにおいて、
    　前記測定した受信電力と所定の閾値とに基づいて、前記開始タイミングを設定する手順を実行させるためのプログラム。     In the program according to claim 17 or 18,
    A program for executing a procedure for setting the start timing based on the measured received power and a predetermined threshold.
  21. 　請求項２０に記載のプログラムにおいて、
    　前記測定した受信電力が前記閾値よりも低い時刻を前記開始タイミングに設定する手順を実行させるためのプログラム。     The program according to claim 20,
    A program for executing a procedure for setting a time at which the measured received power is lower than the threshold as the start timing.
PCT/JP2009/054054 2008-03-28 2009-03-04 Wireless base station, method of controlling wireless signal, and program WO2009119267A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2008-086588 2008-03-28
JP2008086588A JP2009239840A (en) 2008-03-28 2008-03-28 Wireless base station, method for controlling wireless signal, and program

Publications (1)

Publication Number Publication Date
WO2009119267A1 true WO2009119267A1 (en) 2009-10-01

Family

ID=41113472

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2009/054054 WO2009119267A1 (en) 2008-03-28 2009-03-04 Wireless base station, method of controlling wireless signal, and program

Country Status (3)

Country Link
JP (1) JP2009239840A (en)
TW (1) TW201014243A (en)
WO (1) WO2009119267A1 (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5779200B2 (en) * 2013-02-26 2015-09-16 日本電信電話株式会社 Wireless communication system, wireless communication method, base station information management apparatus, and base station information management method

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2000308123A (en) * 1999-04-23 2000-11-02 Ntt Docomo Inc Mobile communication system and synchronizing method in the same
JP2005102319A (en) * 2004-12-07 2005-04-14 Nec Corp Mobile communication system, base station, method for packet transmission timing control, and its program

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2000308123A (en) * 1999-04-23 2000-11-02 Ntt Docomo Inc Mobile communication system and synchronizing method in the same
JP2005102319A (en) * 2004-12-07 2005-04-14 Nec Corp Mobile communication system, base station, method for packet transmission timing control, and its program

Also Published As

Publication number Publication date
JP2009239840A (en) 2009-10-15
TW201014243A (en) 2010-04-01

Similar Documents

Publication Publication Date Title
EP3162144B1 (en) Full duplex operation in a wireless communication network
CN113170453A (en) Reporting beam faults
TW202025811A (en) Method of measurement for layer-1 reference signal received power and user equipment thereof
EP3289795B1 (en) Methods and apparatuses for inter-network measurement in a wireless network
US9532335B2 (en) Wireless communication apparatus and wireless communication method
US8121630B2 (en) Device to sense frequency band to share operating frequency bands in heterogeneous communication systems and method thereof
US20150236808A1 (en) Method and apparatus for radio link adaptation for flexible subframe communications
CN107431543B (en) Base station device and method and system for controlling full duplex transmission
US11089499B2 (en) Candidate beam detection in DRX mode
WO2020034328A1 (en) Interference management in wireless systems
CN113543240A (en) Method, device and terminal for measuring adjacent cell
WO2021022555A1 (en) Method, device and computer readable medium for transmitting prs
WO2009119267A1 (en) Wireless base station, method of controlling wireless signal, and program
CN113491154B (en) Known cell definition with beamforming
US11818755B2 (en) Time sensitive communication
CN109152000B (en) Voice service processing method and device
WO2009119266A1 (en) Control device, method for controlling wireless base station and program
JP6986547B2 (en) Determining feedback timing
US11785512B2 (en) Fallback to conditional handover using SSB reference signal
WO2024065187A1 (en) Communication method, communication apparatus, medium, and program product
US11818710B2 (en) Systems and methods for new-radio-aware LTE scheduling
US20230397033A1 (en) Ue measurement restrictions to protect critical data receptions
WO2023115438A1 (en) Sidelink communication on multiple unlicensed carriers
US20230024809A1 (en) Communication device and communication method that support d2d communication
US20240121627A1 (en) Information transmission method and communication apparatus

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: 09725920

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: 09725920

Country of ref document: EP

Kind code of ref document: A1