JP5574738B2 - Wireless communication system, wireless base station device, control device, and wireless terminal device - Google Patents

Description

  The present invention includes a plurality of 1-to-N type (for example, base station-to-multiple terminals, etc.) wireless networks including a wireless base station apparatus including an antenna capable of directivity control, and the directivity control is coordinated between the plurality of wireless networks. The present invention relates to a wireless communication system, a wireless base station device, a control device, and a wireless terminal device.

  Conventionally, when operating a plurality of adjacent 1-to-N wireless networks using the same frequency band and at the same time, a signal from another wireless network becomes interference, and retransmissions occur frequently, resulting in transmission capacity. There was a problem of reducing. Here, the 1-to-N type wireless network (hereinafter sometimes simply referred to as “wireless network”) refers to a wireless communication network including one wireless base station and a plurality of (N) wireless terminal stations. In general, it is recognized as a system that realizes intra-cell or intra-sector communication in cellular communication. Here, interference refers to interference between wireless devices belonging to different wireless networks, and is generally recognized as inter-cell interference that occurs in cellular communication.

  As a solution to this interference problem, (1) assign different transmission frequency bands to each wireless network, (2) divide the time into a plurality of slots and assign to each wireless network, and (3) differ for each wireless network. For example, a spreading code is assigned to spread a signal in a time direction or a frequency direction.

  However, since the frequency resources and time resources that can be used in wireless communication are limited, there has been a problem that the transmission efficiency decreases when the solutions (1) and (2) are used. In addition, the signal spreading which is the solution of the above (3) realizes avoidance of interference by extending the time or frequency used for communication, so that the transmission efficiency similarly decreases. Since frequency and time resources are required to be injected into the data transmission, splitting or spreading them to avoid interference is not a good solution.

  As a related technique, the following Patent Document 1 discloses a conventional wireless communication system. Specifically, in a wireless communication system having a local base station that communicates with a wireless terminal station and an integrated base station that communicates with a plurality of local base stations through a communication medium such as an optical fiber The integrated base station holds the area information of the beam pattern of the local base station where the wireless terminal station is located and the combination information of the beam patterns that interfere with each other between the local base stations. Packet scheduling of the wireless terminal station is performed so that mutual interference of wireless signals transmitted to the terminal station is suppressed.

JP 2006-270216 A

Yusuke Owatari and 3 others, “Comparison study of various feedback reduction methods in MIMO-OFDM eigenbeam space division multiplexing”, IEICE Transactions B, September 2007, Vol. J90-B, No. 9, p. 885-895 “Adaptive Array and Mobile Communication [I]”, Journal of the Institute of Electronics, Information and Communication Engineers, December 1998, Vol. 81, no. 12, p. 1254-1260 “Adaptive Array and Mobile Communication [II]”, Journal of the Institute of Electronics, Information and Communication Engineers, January 1999, Vol. 82, no. 1, p. 55-61

  However, in the wireless communication system disclosed in Patent Document 1, it is necessary for the integrated base station to accurately grasp the deployment position and beam forming area of each local base station, and the local base stations are fixedly and uniformly arranged. It is desirable. In order to construct a good communication environment in a conventional base station arrangement, design, measurement, installation, and the like by specialized workers are required. For this reason, it is not easy to move a base station once installed, and it is difficult to arbitrarily change the arrangement and frequency allocation of base stations, particularly when there are a plurality of base stations and wireless networks in the vicinity. It was.

  Further, as an embodiment of the technology disclosed in Patent Document 1, when the position and orientation of the local base station are changed, the position of the local base station and the wireless terminal station that the integrated base station has each time It is necessary to update the information regarding the direction, and in this case also, an update work by a specialized worker is required. Moreover, the technique disclosed in Patent Document 1 may not function normally depending on the relocation status of the local base stations.

  In the wireless communication system disclosed in Patent Document 1, the integrated base station performs both beam pattern determination and packet scheduling in a plurality of local base stations. In this case, if the number of target local base stations and radio terminal stations is small, it functions normally, but the number of base stations is several tens to several hundreds, and the number of radio terminal stations is several hundred to several thousand. When the number is large, the beam pattern determination and packet scheduling optimization for each wireless terminal station are computationally enormous and difficult, and may not function normally. Therefore, when the number of control target stations is large, it is desirable to perform beam pattern determination and packet scheduling independently.

  The present invention has been made in view of the above, and reduces mutual interference between wireless networks by performing directivity control in cooperation with wireless base stations in a wireless communication system including a plurality of wireless networks. Then, it aims at obtaining the radio | wireless communications system, radio base station apparatus, control apparatus, and radio | wireless terminal apparatus which can optimize the area coverage of a radio | wireless network.

In order to solve the above-described problems and achieve the object, the present invention includes a plurality of wireless networks including a wireless base station device including a directivity-controllable antenna and a plurality of wireless terminal devices (or dedicated tools), 1 aircraft or upper station of the radio base station apparatus as a radio communication system to a host station, the radio base station apparatus, a MAC control means for performing directional beam control for the own wireless network, wherein Directional beam information of the own radio network obtained from the MAC control means, and the host station obtains directional beam information obtained from each radio base station and transmission path state information relating to the transmission path state of each radio terminal device And a plurality of network management means for managing the MAC control means using the transmission path state information. , And performs instructions for directive beam control.

  According to the present invention, there is an effect that it is possible to reduce interference that a certain wireless network gives to other wireless networks and optimize the area coverage of the wireless network regardless of the arrangement state of the wireless network.

FIG. 1 is a diagram of a configuration example of a wireless communication system according to the first embodiment of the present invention. FIG. 2 is a diagram of a configuration example of a radio base station of the radio communication system according to the first embodiment of the present invention. FIG. 3 is a diagram illustrating an example of a synchronization method between radio base stations in the radio communication system according to the first embodiment of the present invention. FIG. 4 is a diagram illustrating an example of interference between radio networks in the radio communication system according to the first embodiment of the present invention. FIG. 5 is a diagram illustrating an example of directivity control of the wireless communication system according to the first embodiment of the present invention. FIG. 6 is a diagram illustrating an example of directivity control after beam assignment change in the wireless communication system according to the first embodiment of the present invention. FIG. 7 is a diagram illustrating an example of an information exchange procedure for the directional beam pattern test of the wireless communication system according to the first embodiment of the present invention. FIG. 8 is a diagram of a configuration example of a wireless communication system of the wireless communication system according to the second embodiment of the present invention. FIG. 9 is a diagram of a configuration example of an upper station of the wireless communication system according to the second embodiment of the present invention. FIG. 10 is a diagram showing an information exchange procedure for CSI measurement and channel assignment change for each of a plurality of antenna elements in the wireless communication system according to the third exemplary embodiment of the present invention.

  Embodiments of a radio communication system, a radio base station apparatus, a control apparatus, and a radio terminal apparatus according to the present invention will be described below in detail with reference to the drawings. Note that the present invention is not limited to the embodiments.

Embodiment 1 FIG.
FIG. 1 is a diagram showing an outline of the configuration and arrangement of the first embodiment of the wireless communication system according to the present invention. The wireless communication system shown in FIG. 1 includes two wireless networks. Within each wireless network, one wireless base station (corresponding to the wireless base station device of the present invention. ”,“ Base station ”, etc.) is a wireless terminal station (corresponding to the wireless terminal device of the present invention) of N machines (here, three). “Wireless terminal”, “terminal”, etc.) and 1-to-N (here, 1-to-3) communication are performed, and both wireless networks are operated in the same frequency band. And In addition, communication between two wireless networks is established through a base station, a terminal, etc., using a method different from the communication method in each wireless network (here, wired communication using wired 50). And

  In the two wireless networks, the arrangement of the wireless base station and the wireless network according to the used frequency band, transmission power, etc. is not sufficiently designed, and the wireless signal for one wireless network belongs to the other wireless network. It is assumed that the installation position is close enough to be an interference signal to the terminal station.

  Each wireless base station includes an antenna (for example, an array antenna) that can form a plurality of or arbitrary directional beam patterns. In addition, it is assumed that uplink and downlink communications are performed by time division duplex (TDD) for communications within each wireless network. Here, the uplink refers to a line that transmits a signal from the wireless terminal station to the wireless base station, and the downlink refers to a line that transmits a signal from the wireless base station to the wireless terminal station. It is assumed that communication between a wireless base station and a wireless terminal station in each wireless network is established by a multiple access method.

  In FIG. 1, a radio base station 20 constitutes a three-time time division multiple access (TDMA) radio network 30 with three radio terminal stations 901, 902, and 903, and a radio base station 21 An example of a wireless communication system is shown in which three wireless terminal stations 911, 912, and 913 and a one-to-three TDMA wireless network 31 are configured and two wireless networks 30 and 31 are included as a whole. It is assumed that the two wireless base stations 20 and 21 are connected through the wire 50 and communication is established between the wireless base stations 20 and 21.

  FIG. 2 is a block diagram illustrating a configuration example of the radio base station 20 according to the first embodiment. The configuration of the radio base station 21 can be the same as the configuration of the radio base station 20 shown in FIG.

  The radio base station 20 includes a configuration unit 400 having substantially the same configuration as a conventional radio base station device that performs directivity control, and an input / output of an information signal and a MAC unit 422 through a wired 50 between other radio networks. And a plurality of network management units 401 for inputting / outputting information signals between them.

  The configuration unit 400 includes a data unit 421, a MAC (Media Access Control) unit 422, a transmission unit 423, a reception unit 426, a directional beam forming unit 424, and a directivity-controllable antenna 425. Yes.

  The MAC unit 422 constitutes a MAC control unit, and the multiple network management unit 401 constitutes a multiple network management unit.

  The data unit 421 is a circuit that processes data higher than the MAC layer (hereinafter also referred to as “application data”), and inputs / outputs application data s11 and s16 to / from the MAC unit 422. Here, it is assumed that the application data s11 includes address information indicating a transmission destination wireless terminal station, and the application data s16 includes address information indicating a transmission source wireless terminal station.

  The MAC unit 422 outputs the information signal s12 to the transmission unit 423 based on the application data s11 input from the data unit 421. Further, the MAC unit 422 outputs the application data s16 to the data unit 421 based on the detection signal s15 input from the receiving unit 426. Further, the MAC unit 422 outputs beam information (for example, beam pattern number, antenna weight information when an array antenna is used) s17 to the directional beam forming unit 424, and performs directivity control. At this time, the MAC unit 422 outputs the beam information s17 based on the address information indicating the wireless terminal station included in the application data s11 or s16. Further, the MAC unit 422 switches between the transmission mode (downlink) and the reception mode (uplink) for the configuration unit 400. Further, the MAC unit 422 controls the timing of the entire configuration unit 400.

  The transmission unit 423 encodes and modulates the information signal s12 input from the MAC unit 422, and outputs the transmission signal s13 to the directional beam forming unit 424. The receiving unit 426 demodulates and decodes the reception signal s14 detected by the directional beam forming unit 424, and outputs the detection signal s15 to the MAC unit 422.

  The directivity beam forming unit 424 controls the directivity of the transmission signal s13 based on the beam information s17, and outputs it to the antenna 425. Further, the directional beam forming unit 424 detects the input signal from the antenna 425 based on the beam information s17 and outputs the received signal s14 to the receiving unit 426. The antenna 425 transmits a downlink signal to the wireless terminal station and receives an uplink signal from the wireless terminal station.

  Here, signals transmitted and received between a plurality of radio base stations using the wire 50 will be described. In the cable 50, a synchronization signal s25 for synchronizing radio base stations, a command signal s26 for switching communication modes, beam information s28 of a plurality of radio base stations, and radio in a directional beam pattern test described later. Transmission / reception of the transmission path state measurement value s29 at the terminal station is performed.

  Next, input / output signals between the multiple network management unit 401 and the MAC unit 422 will be described. The multiple network management unit 401 receives beam information s19 of the current own wireless network from the MAC unit 422 in the configuration unit 400. In addition, information (transmission path state information) s20 related to the transmission path state in the wireless terminal station of the own wireless network measured in the directional beam pattern test described later is input from the MAC unit 422 to the multiple network management unit 401. The On the other hand, the multiple network management unit 401 is updated by the synchronization signal s21, the communication mode switching signal s22, the multiple network management unit 401 of the own radio base station 20, or the multiple network management unit 401 of another radio base station. Are output to the MAC unit 422.

  Next, synchronization between radio base stations will be described with reference to FIG. FIG. 3 shows an example in which four wireless base stations 20 to 23 are connected via a bus (wired 50). The radio base stations 20 to 23 have the same configuration as described above (see FIG. 2). Here, it is assumed that the wireless base station 20 is a host station that transmits a synchronization request, and the other three wireless base stations 21 to 23 are client stations.

  The synchronization signal s25 includes a synchronization request signal s25a, a response signal s25b to the synchronization request signal s25a, and a synchronization clock s25c. The multiple network management unit 401 in the radio base station 20 that is a host station transmits a synchronization request signal s25a to the radio base stations 21 to 23 that are client stations via a bus (wired 50). The plurality of network management units 401 of the wireless base stations 21 to 23 serving as client stations receive the synchronization request signal s25a, and send a response signal s25b indicating the reception through the bus (wired 50) to the wireless base station serving as the host station. Reply to 20. After confirming that the response signal s25b has been received, the multiple network management unit 401 of the wireless base station 20 that is the host station sends the synchronization clock s25c to the wireless base stations 21 to 23 that are the client stations via the bus (wired 50). Send to. The radio base station 20 that is the host station and the radio base stations 21 to 23 that are the client stations notify the timing of the synchronous clock s25c to the internal MAC unit 422, and the radio base stations 20 to 23 have the same timing. Can be obtained. With the above procedure, the radio base stations 20 to 23 can be synchronized. In the first embodiment, the synchronization method between radio base stations is not limited to this, and any other method may be used as long as synchronization can be established.

  Next, a communication mode switching method of the wireless communication system will be described. First, input / output of the communication mode switching signal s26 and the MAC communication mode switching signal s22 will be described. The multiple network management unit 401 of the host station generates a communication mode switching signal s26 for switching between an intra-network communication mode and a directional beam pattern test mode, which will be described later, and transmits the communication mode switching signal s26 to another wireless base station via the wire 50. The multiple network management unit 401 of the client station receives the communication mode switching signal s26 issued from another radio base station. The communication mode switching signal includes a test end signal for ending the directional beam pattern test mode. The multiple network management unit 401 outputs the MAC communication mode switching signal s22 to the MAC unit 422 in accordance with the communication mode switching signal s26.

  The MAC unit 422 switches between the wireless network communication mode and the directional beam pattern test mode based on the MAC communication mode switching signal s22. When the MAC communication mode switching signal s22 specifies the intra-network communication mode, the MAC unit 422 controls the configuration unit 400 to perform normal TDMA wireless network communication. On the other hand, when the MAC communication mode switching signal s22 specifies the directional beam pattern test mode, the MAC unit 422 adjusts the operation timing of the configuration unit 400 according to the information exchange procedure of the directional beam pattern test mode described later. The beam information s17 of the beam pattern to be tested is appropriately output to the directional beam forming unit 424, and the data signal for training signal is output to the transmission unit 423. At this time, the transmission unit 423 generates a training signal according to the training signal data signal, and outputs the training signal to the directional beam forming unit 424.

  Next, the inter-base station cooperative beam control performed in the multiple network management unit 401 of the host station will be briefly described. Details of this will be described later. First, input / output information necessary for the multiple network management unit 401 will be described. The multiple network management unit 401 receives from the MAC unit 422 the current beam information s19 of the own wireless network, information (transmission state information) s20 related to the transmission path state at the wireless terminal station of the own wireless network, Using the beam information s28 of the other radio network received from the radio base station and the information (transmission path status information) s29 regarding the transmission path status at the radio terminal station of the other radio network, according to the beam control procedure described later. , Update beam information. The updated beam information s24 of the own wireless network is output from the multiple network management unit 401 to the MAC unit 422. The updated beam information s28 of the other wireless network is transmitted from the multiple network management unit 401 to another wireless base station (client station) through the wire 50.

  The beam information s24 is input from the multiple network management unit 401 to the MAC unit 422. The MAC unit 422 changes the directional beam pattern according to the information. The multiple network management unit 401 of another radio base station receives the updated beam information s28 and outputs the update information to the MAC unit 422 of the configuration unit 400 in each radio base station. The MAC unit 422 The directional beam pattern is changed based on the updated information.

  Next, an example of a problem that may occur when the wireless communication system shown in FIG. 1 is operated will be described with reference to FIG. Hereinafter, a case where downlink communication is performed in each wireless network will be described as an example. Also, here, for simplicity, a case where directivity control is not performed in each radio base station is illustrated. When the two wireless networks 30 and 31 perform downlink communication together, signals for the own wireless network are transmitted from the two wireless base stations 20 and 21, respectively. At this time, if the wireless terminal station 901 belonging to the wireless network 30 and the wireless terminal station 911 belonging to the wireless network 31 use the same time slot and are close to each other (see FIG. 4), the wireless base station It is possible that a signal transmitted from the station 20 to the wireless terminal station 901 reaches the wireless terminal station 911 and becomes an interference signal in the wireless terminal station 911. When interference occurs in the wireless terminal station 911 as described above, the signal transmitted from the wireless base station 21 to the wireless terminal station 911 is not correctly demodulated in the wireless terminal station 911, and the wireless terminal station 911 is not connected between the wireless base station 21 and the wireless terminal station 911. Communication quality will deteriorate. Hereinafter, such interference occurring between wireless networks is referred to as inter-network interference.

  Next, an example of a problem that may occur when directivity control is performed in a radio base station and an example in which communication quality is improved will be described with reference to FIG. FIG. 5 is a diagram illustrating an outline of a directional beam when directivity control is performed in the radio base station 20. In the example of FIG. 5, it is assumed that the radio base station 20 can form the directional beam 201 and the directional beam 202. Here, as shown in FIG. 5, the directional beam 201 is a beam having directivity in the direction in which the wireless terminal station 901 is located, and the directional beam 202 is directed in the direction in which the wireless terminal station 903 is located. It is assumed that the beam has

  As shown in FIG. 5, when the radio base station 20 transmits a signal toward the own radio network 30 using the directional beam 201, the quality of the signal received by the radio terminal station 901 is improved. However, when the directional beam 201 reaches the wireless network 31, particularly when the wireless terminal station 911 uses the same time slot as the wireless terminal station 901, interference may occur in the wireless terminal station 911. On the other hand, the directional beam 202 has low directivity to the wireless network 31 and high directivity to the own wireless network 30, so that even if the wireless terminal station 911 uses the same time slot as the wireless terminal station 901. The radio terminal station 911 can reduce interference and perform good communication within the own radio network 30. To achieve this, directivity control and time slot allocation (hereinafter referred to as “channel allocation” or “ "Scheduling" may be called at the same time.) When the number of control target stations is large, the amount of calculation becomes enormous and optimization becomes difficult. Although two directional beams are shown in FIG. 5, the number of directional beam patterns may be any number, and an arbitrary directional beam may be formed.

  The magnitude of the interference described above depends on the directivity pattern and the position of the wireless device or wireless network. Therefore, the wireless terminal stations belonging to each wireless network are viewed macroscopically, and beam forming is performed cooperatively between the wireless networks. The procedure will be described below.

  In the first embodiment, the wireless network 30 and the wireless network 31 cooperate with each other to change the beam pattern. FIG. 6 is a diagram illustrating an example in which a beam pattern is changed in cooperation between networks. A directional beam 203 radiated from the radio base station 20 directs radio waves only to each radio terminal station in the radio network 30 and is controlled so that radio waves do not reach the radio network 31 as much as possible. It has become. On the other hand, the same applies to the directional beam 213 radiated from the radio base station 21. The beam pattern is controlled so that radio waves do not reach the radio network 30 as much as possible. That is, the directional beams 203 and 213 have a pattern in which nulls are directed toward the other wireless network. Thus, by determining the beam pattern in cooperation between the wireless networks, the interference between networks can be reduced, and a plurality of multi-access wireless networks can coexist.

  In order to perform directivity control by such inter-network cooperation, information (transmission path state information) about the transmission path state between the wireless base station of the own wireless network and the wireless terminal station of the other wireless network is known (information Need to be replaced). In the first embodiment, received signal strength (Received Signal Strength Indicator: RSSI) is used as information on the transmission path state, and RSSI is measured at each wireless terminal station. The procedure for measuring the RSSI and determining the beam pattern is shown below, but is not limited to this, it may be estimated using a known signal such as a sounding signal, a preamble signal, a pilot signal, etc. Also good. In this case, synchronization between base stations may not be established, and may be estimated during normal communication without switching to a beam pattern measurement mode described later. In addition, although the timing of RSSI measurement and beam pattern determination is specified below, these may be performed at an arbitrary timing.

  FIG. 7 is a diagram showing a diagram of an information exchange procedure between wireless devices (wireless base station and wireless terminal station) for performing RSSI measurement between the wireless base station 20 and the wireless terminal stations 911, 912, and 913. is there. In FIG. 7, information exchange by wireless communication is indicated by a solid line block, and information exchange by communication via the wire 50 is indicated by a broken line block. Here, the details are described focusing on the information exchange in the wireless network 31, but the same information exchange between the wireless base station 21 and the wireless terminal stations 901, 902, and 903 is also performed with respect to the wireless network 30. Done. In this example, the RSSI measurement is performed on the directional beam 201, the directional beam 202, and the directional beam 203 emitted from the radio base station 20, but the directional beam usable by the radio base station 20 is used. RSSI measurement may be performed for the number of candidate directional beam patterns within the range of the number of patterns.

  In FIG. 7, each wireless network performs normal wireless communication in the normal network communication mode until section D1, and starts RSSI measurement from section D2. First, between the wireless base stations, synchronization between the wireless base station 20 and the wireless base station 21 is established through the wired 50 by a synchronization signal from the plurality of network management units 401 of the wireless base station 20 (section D2). Next, the entire radio network is switched from the intra-network communication mode to the directional beam pattern test mode (RSSI measurement mode) with the radio base station 20 by the communication mode switching signal transmitted from the plurality of network management units 401 of the radio base station 20. (Section D3).

  The radio base station 20 first broadcasts a training signal known to all radio terminal stations using the directional beam 201, and the radio terminal stations 911, 912, and 913 receive the signal and measure RSSI (section). D4). The RSSI measured by the wireless terminal stations 911, 912, and 913 is sequentially notified to the wireless base station 21 of the wireless network 31 (section D5). The radio base station 21 feeds back the information as a measurement value of the directional beam 201, that is, a transmission path state measurement value s29, to the radio base station 20 through the wire 50 (section D6). Similarly, the radio base station 20 broadcasts a training signal using the directional beam 202, the radio terminal stations 911, 912, and 913 receive the signal, measure RSSI, and the measured RSSI is a radio signal. Notification is sequentially made to the radio base station 21 of the network 31. Finally, the radio base station 20 broadcasts a training signal using the directional beam 203 (section D7), and the RSSI measured by the radio terminal stations 911, 912, and 913 is transmitted to the radio base station 21 of the radio network 31. Notification is made sequentially (section D8). The radio base station 21 feeds back the information as a measurement value of the directional beam 203, that is, a transmission path state measurement value s29, to the radio base station 20 through the wire 50 (section D9).

  When the above test is completed, the multiple network management unit 401 of the radio base station 20 transmits a test end signal to each radio base station (here, the radio base station 21) using the inter-network communication mode switching signal s26. The test is terminated (section D10). The multiple network management unit 401 of the radio base station 20 performs beam allocation processing (beam pattern information change processing) based on the collected RSSI measurement values (section D11). Details of this beam allocation processing will be described later.

  The multiple network management unit 401 of the radio base station 20 notifies the changed beam pattern information to the radio base station 21 through the wired 50 (section D12). Thereafter, the radio base station 21 requests the radio terminal stations 911, 912, and 913 to switch to the normal communication mode (section D14), and each radio network returns to the normal network communication mode (section D15).

  Next, the beam allocation process performed by the multiple network management unit 401 of the radio base station 20 in the section D11 will be described in detail. In section D11, the multiple network management unit 401 of the radio base station 20 performs a beam allocation process for simultaneously reducing interference with other radio networks and improving communication quality of the own radio network based on the collected RSSI measurement values. I do. An example of the process will be described below.

  The multiple network management unit 401 of the radio base station 20 first selects some beam pattern candidates that provide good communication quality within the own radio network 30 from the RSSI measurement values of the collected own radio network 30. Among them, the directional beam pattern 203 that minimizes the interference with the other radio network 31 is selected. This is a beam pattern used by the radio base station 20. In the above example, the beam pattern allocation is performed with priority on the communication quality of the own wireless network, but the allocation may be performed with priority on reducing interference with other wireless networks. The selection of the beam pattern described above may be determined based on the average value of RSSI measurement values, or may be determined from the distribution of RSSI measurement values. Further, the transmission power of the corresponding beam pattern may be determined simultaneously with the determination of the beam pattern. Thereby, the network area range can be optimized.

  Thus, inter-network interference can be reduced by determining beam patterns in cooperation between wireless networks. Each radio base station can perform scheduling optimization for each radio network by performing communication scheduling so that the communication characteristics of each radio terminal station are good when the determined beam pattern is used. That is, according to the above procedure, directivity control and communication scheduling can be optimized independently, and even when the number of wireless networks and the number of wireless terminal stations is increased, they can be similarly optimized.

  The above-mentioned directional beam pattern test and beam assignment change may be performed periodically, or only when the transmission path state changes, or when the traffic in the wireless network is low. Alternatively, it may be performed at an arbitrary timing by the network administrator. If beam assignment is changed periodically, inter-network interference caused by a change in transmission path state can be prevented, and the communication quality of each wireless network can be maintained. Further, if the beam assignment change is performed only when the transmission line state changes, it is possible to prevent the beam assignment change when the transmission line state does not change, and the data transmission efficiency can be improved. Further, if it is performed when the data traffic is small, it is possible to suppress a decrease in data transmission efficiency due to the directional beam pattern test and the beam assignment change. In addition, if the network administrator changes the beam assignment at an arbitrary timing, the network administrator can change the beam assignment at a desired timing.

  In the first embodiment, the radio base station 20 performs directional beam control on the assumption that the radio base station 20 is an interfering device and the radio terminal stations 911, 912, and 913 in the radio network 31 are interfered devices. Explained the procedure. However, not limited to this, when the radio base station 21 is an interfering device and the radio terminal stations 901, 902, and 903 in the radio network 30 are interfering devices, the radio base station 21 performs directivity in the same procedure. Beam control may be performed. Moreover, although the above description was given taking downlink communication as an example, similar directivity control may be performed on the uplink. By performing the above-described directivity control in the uplink, each radio base station can reduce signal reception from radio terminal stations of other radio networks and improve signal reception quality from radio terminal stations of its own radio network. .

  In the first embodiment, transmission / reception of signals in the wireless network is performed by TDD. However, the present invention is not limited to this, and transmission and reception of signals may be performed by frequency division duplex (FDD).

  In the first embodiment, an array antenna configured by two antennas is illustrated as the antenna 425 with directivity control provided in the radio base station illustrated in FIG. 1 and FIG. 2, but a plurality of or arbitrary directivities are illustrated. Other antennas may be used as long as they can form a beam pattern, and the number of antennas may be increased. For example, a plurality of antennas each having directivity may be provided, and these antennas may be physically switched, or antennas having a plurality of polarization modes may be used.

  In the first embodiment, the case where the number of wireless networks is 2 is illustrated. However, the present invention is not limited to this, and even when the number of wireless networks is three or more, beam assignment by inter-network cooperation can be realized by the same procedure.

  In the first embodiment, the case where TDMA is used as the communication method in the wireless network is illustrated. However, the present invention is not limited to this, and any scheme that realizes multiple access may be used, and Frequency Division Multiple Access (FDMA), Orthogonal Frequency Division Multiple Access (Orthogonal FDMA: OFDMA), or Code Division Multiple Access (Code Code). (Division Multiple Access: CDMA) may be used.

  In this Embodiment 1, it illustrated about the case where the number of radio | wireless terminal stations of each radio | wireless network is the same (the number of terminals N). However, the present invention is not limited to this, and the number of wireless terminal stations in each wireless network may be an arbitrary number.

  In the first embodiment, the case where the multiple network management unit 401 of the radio base station 20 generates a synchronization clock and transmits the synchronization signal to the radio base station 21 to establish synchronization is illustrated. However, the present invention is not limited to this. For example, the radio base station 21 may generate and transmit a synchronization signal, and the radio base station 20 may receive the synchronization signal and establish synchronization. Further, synchronization may be established by using an external signal such as time data of a satellite positioning system (GPS) as a synchronization signal.

  In the first embodiment, the case where the wireless base stations are connected by wire is illustrated. However, the present invention is not limited to this, and wireless base stations may be connected by wireless communication, or may be connected via a terminal. Further, as will be described in a second embodiment described later, a plurality of radio base stations may be connected via an upper station different from the radio device.

  In this Embodiment 1, the case where RSSI was used as information (transmission path state information) regarding the transmission path state was illustrated. However, the present invention is not limited to this, and the received signal power to noise power ratio (Signal to Noise power Ratio: SNR), the carrier power to noise power ratio (CNR), and the carrier power to interference noise power indicating the reception quality. Ratio to carrier noise ratio (CINR), received signal power to interference power ratio (SIR), received signal power to interference noise power ratio (Signal to Interference Noise Ratio, or Noise to Interference Noise Noise Ratio) A combination of these may be used.

  In this Embodiment 1, it illustrated about the case where RSSI is fed back to the radio base station 20 from the radio base station 21 for every directional beam pattern test. However, the present invention is not limited to this, and all RSSIs may be fed back collectively after the test of all beam patterns is completed. Further, as information to be fed back, CSI described later and beam information (beam number, antenna weight information, etc.) may be fed back in addition to information indicating a reception state such as RSSI. Further, since wireless communication and wired communication can be performed independently, wired communication in the sections D6 and D9 in FIG. 7 may be performed in parallel with the RSSI measurement. In addition, the RSSI notification from the wireless terminal station to the wireless base station in the period D5 and the period D8 in FIG. 7 is performed by dividing the time slot for each wireless terminal station. For example, FDMA, OFDMA, or CDMA When such a multi-access scheme is adopted, since different frequency channels or spreading codes are assigned to the respective radio terminal stations, all the radio terminal stations may transmit at the same time.

  In the first embodiment, the case where the radio base station performs communication using the same directional beam pattern in the radio frequency band to be used is illustrated. However, the present invention is not limited to this, and a radio frequency band to be used is divided into a plurality of bands (referred to as subbands, resource blocks, or subcarriers), and a directional beam pattern is determined for each subband by the above-described procedure. Sex control may be implemented.

  In the first embodiment, the number of antennas provided in the wireless terminal station is not clearly shown, but a single antenna or a plurality of antennas may be used.

  As described above, in the first embodiment, the radio base station acquires RSSI measurement values in each directional beam pattern in cooperation with other radio base stations, and based on the RSSI measurement values, the directional beam of each radio network is obtained. The pattern assignment was changed. Thereby, compared with the case where beam pattern allocation change is not performed, the interference between networks can be reduced and the communication quality in a network can be improved. Further, since the radio base station 20 has a known reception level at all radio terminal stations, the radio base station 20 has a transmission power (a radio base station at the time of downlink) to such an extent that a ratio of desired signal to interference signal power in communication within the network can be sufficiently secured. The transmission power of the wireless terminal station and the transmission power of the wireless terminal station at the time of uplink) can further reduce interference with other wireless networks, and can also reduce power consumption.

Embodiment 2. FIG.
FIG. 8 is a diagram showing an outline of the configuration and arrangement of the second embodiment of the wireless communication system according to the present invention. In the radio communication system according to the second exemplary embodiment, as illustrated in FIG. 8, the radio base station 20 and the radio base station 21 are connected by wires 51 and 52 via the upper station 40. Since other than that is the same as that of Embodiment 1, the same code | symbol as Embodiment 1 (refer FIG. 1 etc.) is attached | subjected to each component. The upper station 40 constitutes a control device.

  FIG. 9 is a diagram illustrating a configuration example of the upper station 40. The upper station 40 includes a plurality of network management units 401. The multiple network management unit 401 of the upper station 40 constitutes a multiple network management unit, and the multiple network management unit 401 (see FIG. 2) of the radio base stations 20 and 21 constitutes its own radio network management unit.

  The upper station 40 transmits the synchronization clock s25c (see FIG. 3) to the radio base stations 20 and 21 through the wires 51 and 52. That is, the upper station 40 corresponds to the host station in FIG. 3 described in the first embodiment, the radio base stations 20 and 21 correspond to the client stations, and the upper station is operated by the synchronization procedure described in the first embodiment. 40, synchronization between the radio base stations 20, 21 can be established. Note that information and signals transmitted and received through the wires 51 and 52 are the same as the information and signals transmitted and received through the wire 50 in the first embodiment, including the synchronization signal.

  In the second embodiment, the upper station 40 determines the directional beam pattern used by the radio base stations 20 and 21, and the radio base stations 20 and 21 receive the information through the wires 51 and 52, Directional beam forming is performed based on the information. That is, the procedure performed by the radio base station 20 in the sections D2, D6, D9, D10, D11, and D12 in the information exchange of the first embodiment (see FIG. 7) is all performed by the upper station 40 in the second embodiment. .

  In addition, the radio base station 21 performs the directional beam pattern test that the radio base station 20 performs in the first embodiment in the same manner, so that the radio terminal station in the case where the radio base station 21 forms a directional beam. The RSSIs at 901, 902, and 903 can be measured, and the upper station 40 can collect them in the same procedure as described above. Based on the RSSI measurement value when the radio base station 20 forms a directional beam and the RSSI measurement value when the radio base station 21 forms a directional beam, the upper station 40 determines both of the radio networks 30 and 31. A directional beam pattern that achieves interference reduction or communication quality improvement can be determined. Note that the directional beam pattern test performed by the radio base station 20 and the directional beam pattern test performed by the radio base station 21 may be performed at arbitrary timings, respectively, and RSSI measurement values from each radio base station to the upper station 40 are measured. The timing of notifying may be arbitrary. As in the first embodiment, the RSSI measurement method is not limited to this, and may be estimated using a known signal such as a sounding signal, a preamble signal, or a pilot signal, or may be estimated from communication data.

  The upper station 40 notifies the radio base stations 20 and 21 of the determined directional beam information (for example, a beam number, an antenna weight coefficient, etc.) in the section D12 of FIG. At this time, the upper station 40 may notify the information for the wireless network 30 to the wireless base station 20 and the information for the wireless network 31 to the wireless base station 21. The multiple network management unit 401 of the radio base station 20 receives the information, and the MAC unit 422 of the radio base station 20 performs directional beam control according to the received information. The wireless base station 21 performs the same processing as that of the wireless base station 20 described above. Note that the directional beam information described above may include transmission power information.

  In the second embodiment, the case where the upper station 40 is connected to the radio base station 20 via the wire 51 and connected to the radio base station 21 via the wire 52 is illustrated. However, the present invention is not limited to this, and the upper station 40 may be connected to an external network by a wired medium or a wireless medium in addition to connection with a plurality of wireless base stations.

  In the second embodiment, the case where the upper station 40 manages two networks of the wireless network 30 and the wireless network 31 is illustrated. However, the present invention is not limited to this, and the upper station 40 may manage three or more wireless networks. In this case, one wireless network may cause interference with other wireless networks, but forms a beam pattern that macroscopically reduces the interference with respect to the plurality of wireless networks. Alternatively, a beam pattern may be formed that reduces interference with a specific wireless network.

  As described above, in the second embodiment, the radio base station 20 and the radio base station 21 are connected via the upper station 40, and the upper station 40 is used by the radio base stations 20 and 21 for the radio terminal station. We decided to assign a directional beam pattern. As a result, the directional beam pattern assignment changing process performed by the plurality of network management units 401 of the radio base station 20 in the first embodiment is performed in the upper station 40, so that the processing amount in the radio base station is reduced. In particular, it can be reduced.

Embodiment 3 FIG.
In the third embodiment, unlike the first and second embodiments, the channel state information itself (Channel State Information) is used as information (channel state information) regarding the channel state between the radio base station and the radio terminal station. : CSI). In addition, an array antenna is used as the antenna 425 (see FIG. 2) capable of directivity control provided in the radio base station. In the third embodiment, array antenna 425 is configured to include a first antenna element and a second antenna element. Except for these matters, the configurations of the radio communication system and the radio base station apparatus according to the third embodiment are the same as those in the second embodiment (see FIG. 8). The configuration of the third embodiment may be the same as that of the first embodiment (see FIG. 1).

  In the third embodiment, CSI between the wireless terminal stations 911, 912, and 913 and each antenna element included in the wireless base station 20 is used. Therefore, in this third embodiment, instead of the RSSI measurement mode (see sections D4 to D10 in FIG. 7) in the directional beam pattern test of the first or second embodiment, CSI measurement is performed as shown in FIG. Mode (see sections D4 to D10 in FIG. 10).

In order to measure CSI for each antenna element, as shown in FIG. 10, a training signal may be transmitted by changing the transmission time for each antenna element (see sections D4 and D7 in FIG. 10), and CSI may be acquired. . Alternatively, a code for identifying an antenna element may be multiplied on the training symbol sequence and transmitted simultaneously from all antenna elements (for example, a Long Training Field (High-Throughput preamble of the wireless LAN standard IEEE 802.11n) (HT-LTF) can be used, such as the code matrix _PHTLF used in HT-LTF) or the Walsh-Hadamard code matrix described in FIG. In addition, when multiplying codes for antenna element identification, it is necessary for radio terminal stations to have the same code, but by multiplying the received symbol by a code that matches the target antenna element, a linear sum is obtained. The CSI between the antenna element and the antenna element can be measured.

  The CSI measured at the wireless terminal station is notified to the upper station 40 in the same procedure as in the second embodiment. The upper station 40 uses the collected CSI to determine the antenna weight for forming the directional beam. For example, by determining the antenna weight using the Zero-Forcing (ZF) algorithm described in Non-Patent Document 2 and notifying it to the radio base stations 20 and 21, each radio base station is subject to interference with another radio network. High precision null can be directed to

  Although the case where the number of wireless terminals in each wireless network is 3 is illustrated here, the present invention can be similarly applied to the case where the number of wireless terminals is 4 or more. Further, although the case where the number of wireless networks is 2 is illustrated here, the present invention can be similarly applied even when the number of wireless networks is 3 or more.

  In the third embodiment, the ZF algorithm has been described as an example of the algorithm for determining the antenna weight of the array antenna. However, the present invention is not limited to this, and the antenna weight is determined by the MMSE (Minimum Mean Square Error) algorithm described in Non-Patent Document 3 and notified to the radio base stations 20 and 21, so that the radio terminal station of another radio network It is also possible to form an optimum directional beam that reduces the interference with the SNR and improves the SNR of the intra-radio network communication. Further, eigenvalues and eigenvectors may be calculated from the measured CSI as representative CSI of each wireless network, and the antenna weight may be calculated based on the eigenvalue and eigenvector. Thereby, CSI used as a calculation object can be reduced. Further, the antenna weight pattern having the strongest tendency is selected from a plurality of antenna weight patterns (also called codebooks) prepared in advance by the radio base station, and the information is notified to the radio base station 20 and the radio base station 21. By doing so, a directional beam may be formed. Note that the antenna weight determination method is not limited to this. In addition to the determination of the antenna weight, the transmission power used simultaneously with the antenna weight may be determined.

  In the third embodiment, the case where the radio base station performs communication using the same directional beam pattern in the radio frequency band to be used is illustrated. However, the present invention is not limited to this, and as in the first embodiment, the directional beam pattern and transmission power may be determined for each subband by the above-described procedure.

  As described above, since the third embodiment is based on the second embodiment, the overall configuration of the assumed wireless communication system is the same as that in FIG. In FIG. 8, each of the radio base stations 20 and 21 includes two antenna elements. However, the present embodiment is not limited to this. good. In order to effectively reduce interference between networks, the number of antenna elements is preferably equal to or greater than the sum of the desired wireless terminal station and the interfered wireless terminal station, but this is not restrictive.

  As described above, in Embodiment 3, an array antenna is mounted on a radio base station, CSI between each antenna element of the radio terminal station and the radio base station is acquired, and antenna weights are determined by a beam forming algorithm. It was decided to. This enables more precise directivity control in the radio base station than in the first or second embodiment, and the area coverage of each radio network can be optimized regardless of the location of the base stations.

  The present invention has been described based on the embodiments. It is understood by those skilled in the art that these embodiments are exemplifications, and that various modifications can be made to combinations of the respective constituent elements and processing processes, and such modifications are also within the scope of the present invention. By the way.

  As described above, the wireless communication system, the wireless base station device, the control device, and the wireless terminal device according to the present invention are useful for a wireless communication system including a plurality of wireless networks.

20, 21, 22, 23 Wireless base station 30, 31 Wireless network 40 Upper station 50, 51, 52 Wired 201, 202, 203, 213 Directional beam 400 Configuration unit 401 Multiple network management unit 421 Data unit 422 MAC unit 423 Transmission Unit 424 directional beam forming unit 425 directivity control antenna 426 receiving unit 901, 902, 903, 911, 912, 913 wireless terminal station

Claims (62)

A wireless communication system comprising a plurality of wireless networks including a wireless base station device and a plurality of wireless terminal devices each having an antenna capable of directivity control, wherein one of the wireless base station devices is a host station,
The radio base station apparatus that operates as the host station is
MAC control means for performing directional beam control and communication scheduling for the own wireless network;
Directional beam information and communication schedule information of the own radio network obtained from the MAC control means, directional beam information and communication schedule information obtained from the other radio network, and all obtained from the own radio network and the other radio network A plurality of transmission path state information for signals transmitted to the wireless terminal apparatus under different conditions between the same wireless base station apparatus and the same wireless terminal apparatus, regarding the transmission path state of the wireless terminal apparatus in the wireless network; Multiple network management means for managing
With
The plurality of network management means uses the transmission path state information to instruct the MAC control means and the other wireless network about communication scheduling and directional beam control.
A wireless communication system.   The radio communication system according to claim 1, wherein control timing synchronization of each radio base station apparatus is established by transmitting and receiving a synchronization signal between radio base station apparatuses of the plurality of radio networks. The uplink and downlink in the plurality of wireless networks are performed by time division duplex,
In the plurality of wireless networks, uplink is performed at the same timing, and downlink is performed at the same timing.
The wireless communication system according to claim 2. The signal transmission / reception within the plurality of wireless networks is performed by time division multiple access,
Controlling the divided time slots at the same timing in the plurality of wireless networks;
The wireless communication system according to claim 2, wherein the wireless communication system is a wireless communication system. Signal transmission and reception within the plurality of wireless networks is performed by frequency division multiple access, orthogonal frequency division multiple access, or code division multiple access.
The wireless communication system according to claim 2, wherein the wireless communication system is a wireless communication system. The plurality of network management means for instructing another wireless network to switch between an intra-network communication mode for performing normal intra-network communication and a transmission path state measurement mode for measuring the transmission path state of the wireless terminal device. Send a mode switching signal,
The wireless communication system according to any one of claims 1 to 5. The radio base station apparatus operating as the host station performs control to switch the communication mode of the other radio network from the intra-network communication mode to the transmission path state measurement mode by transmitting the mode switching signal, and has a plurality of directivities. A beam pattern is used to transmit a training signal known by the wireless terminal device of the other wireless network,
A wireless terminal apparatus that performs transmission path state measurement calculates transmission path state information for each directional beam pattern using a received signal and a known training signal, and transmits transmission path state information for each directional beam pattern. Notifying the wireless base station device of its own wireless network,
The wireless communication system according to claim 6. The transmission path state information is information including reception signal strength, reception signal power to noise power ratio and / or carrier power to noise power ratio.
The wireless communication system according to claim 7. The radio base station apparatus operating as the host station includes an array antenna including a plurality of antenna elements, and transmits the mode switching signal to change the communication mode of the other radio network from the intra-network communication mode to the transmission path state. Control to switch to the measurement mode, for each of the antenna elements, transmit a training signal known to the wireless terminal device of the other wireless network,
A wireless terminal apparatus that performs transmission path state measurement calculates transmission path state information for each antenna element using a received signal and a known training signal, and transmits transmission path state information for each antenna element of the own wireless network. Notifying the radio base station device,
The wireless communication system according to claim 6.   The wireless communication system according to claim 9, wherein the transmission path state information is CSI. The multiple network management means calculates antenna weights of each antenna element as directional beam control.
The wireless communication system according to claim 9 or 10, characterized in that   The wireless communication system according to any one of claims 7 to 11, wherein the communication mode switching is performed at a predetermined time period.   The wireless communication system according to any one of claims 7 to 11, wherein the communication mode switching is performed at an arbitrary time timing. A wireless communication system comprising a plurality of wireless networks including a wireless base station device and a plurality of wireless terminal devices each including an antenna capable of directivity control, and a control device capable of communicating with each wireless base station device,
The wireless base station device
MAC control means for performing directional beam control and communication scheduling for the own wireless network;
Own radio network management means for managing directional beam information and communication schedule information of the own radio network obtained from the MAC control means;
With
The control device includes:
Between the same radio base station apparatus and the same radio terminal apparatus regarding the directional beam information and communication schedule information obtained from all radio networks and the transmission path state of the radio terminal apparatus in all radio networks obtained from the all radio networks. A plurality of network management means for managing a plurality of transmission path state information for signals transmitted to the wireless terminal device under different conditions by the wireless base station device ;
With
The plurality of network management means, using the transmission path state information, to give instructions regarding communication scheduling and directional beam control for all wireless networks,
A wireless communication system.   The radio communication system according to claim 14, wherein the control apparatus transmits a synchronization signal, and each radio base station apparatus receives the synchronization signal, thereby establishing control timing synchronization of each radio base station apparatus. . The control device instructs the plurality of wireless networks to switch between an intra-network communication mode for performing normal intra-network communication and a transmission path state measurement mode for measuring the transmission path state of the wireless terminal device. Send a mode switching signal,
The wireless communication system according to claim 14 or 15, The control device performs control to switch the communication mode of all wireless networks from the intra-network communication mode to the transmission path state measurement mode by transmitting the mode switching signal,
The wireless base station device of all wireless networks uses a plurality of directional beam patterns to transmit a training signal known to wireless terminal devices of other wireless networks,
A wireless terminal apparatus that performs transmission path state measurement calculates transmission path state information for each directional beam pattern using a received signal and a known training signal, and transmits transmission path state information for each directional beam pattern. Notifying the wireless base station device of its own wireless network,
The wireless communication system according to claim 16. The transmission path state information is information including reception signal strength, reception signal power to noise power ratio and / or carrier power to noise power ratio.
The wireless communication system according to claim 17. The control device performs control to switch the communication mode of all wireless networks from the intra-network communication mode to the transmission path state measurement mode by transmitting the mode switching signal,
The radio base station apparatus of all radio networks is provided with an adaptive array antenna including a plurality of antenna elements, and for each antenna element, transmits a training signal known to a radio terminal apparatus of another radio network,
A wireless terminal apparatus that performs transmission path state measurement calculates transmission path state information for each antenna element using a received signal and a known training signal, and transmits transmission path state information for each antenna element of the own wireless network. Notifying the radio base station device,
The wireless communication system according to claim 16.   The wireless communication system according to claim 19, wherein the transmission path state information is CSI. The multiple network management means calculates antenna weights of each antenna element as directional beam control.
The wireless communication system according to claim 19 or 20, wherein the wireless communication system is a wireless communication system.   The radio communication system according to any one of claims 17 to 21, wherein the communication mode switching is performed at a predetermined time period.   The wireless communication system according to any one of claims 17 to 21, wherein the communication mode switching is performed at an arbitrary time timing. A radio base station apparatus used in a radio communication system comprising a plurality of radio networks including a radio base station apparatus and a plurality of radio terminal apparatuses, wherein one of the radio base station apparatuses is a host station,
An antenna that can control directivity;
MAC control means for performing directional beam control and communication scheduling for the own wireless network;
Directional beam information and communication schedule information of the own radio network obtained from the MAC control means, directional beam information and communication schedule information obtained from the other radio network, and all obtained from the own radio network and the other radio network A plurality of transmission path state information for signals transmitted to the wireless terminal apparatus under different conditions between the same wireless base station apparatus and the same wireless terminal apparatus, regarding the transmission path state of the wireless terminal apparatus in the wireless network; Multiple network management means for managing
A radio base station apparatus comprising: The plurality of network management means uses the transmission path state information to instruct the MAC control means and the other wireless network about communication scheduling and directional beam control.
The radio base station apparatus according to claim 24. Provide an adaptive array antenna including a plurality of antenna elements,
The multiple network management means calculates antenna weights of each antenna element as directional beam control.
The radio base station apparatus according to claim 24 or 25. A control apparatus for controlling a radio communication system including a plurality of radio networks including a radio base station apparatus including a directivity-controllable antenna and a plurality of radio terminal apparatuses,
Between the same radio base station apparatus and the same radio terminal apparatus regarding the directional beam information and communication schedule information obtained from all radio networks and the transmission path state of the radio terminal apparatus in all radio networks obtained from the all radio networks. A plurality of network management means for managing a plurality of transmission path state information for signals transmitted to the wireless terminal device under different conditions by the wireless base station device ;
A control device comprising: The plurality of network management means, using the transmission path state information, to give instructions regarding communication scheduling and directional beam control for all wireless networks,
The control device according to claim 27. The radio base station apparatus includes an adaptive array antenna including a plurality of antenna elements,
The multiple network management means calculates antenna weights of each antenna element as directional beam control.
29. The control device according to claim 27 or 28, wherein: A wireless terminal device used in the wireless communication system according to claim 7 or 17,
Using reception signals and known training signals, calculate transmission path state information for each directional beam pattern, and notify the wireless base station apparatus of the own wireless network of transmission path state information for each directional beam pattern.
A wireless terminal device. A wireless terminal device used in the wireless communication system according to claim 9 or 19,
Using reception signals and known training signals, calculate transmission path state information for each antenna element, and notify the wireless base station apparatus of the own wireless network of transmission path state information for each antenna element.
A wireless terminal device. A wireless communication system comprising a plurality of wireless networks including a wireless base station device and a plurality of wireless terminal devices each having an antenna capable of directivity control, wherein one of the wireless base station devices is a host station,
The radio base station apparatus that operates as the host station is
MAC control means for performing directional beam control within the own wireless network;
Directional beam information of the own radio network obtained from the MAC control means, directional beam information obtained from the other radio network, and transmission of radio terminal apparatuses in all radio networks obtained from the own radio network and the other radio network A plurality of network management means for managing a plurality of transmission path state information for signals transmitted to the wireless terminal device under different conditions between the same wireless base station device and the same wireless terminal device, regarding the path state; ,
With
The plurality of network management means uses the transmission path state information to instruct the MAC control means and the other wireless network about directional beam control.
A wireless communication system. Signal transmission and reception within the plurality of wireless networks is performed by time division multiple access, frequency division multiple access, orthogonal frequency division multiple access, or code division multiple access.
The wireless communication system according to claim 32.   The radio communication system according to claim 32 or 33, wherein control timing synchronization of each radio base station apparatus is established by transmitting and receiving a synchronization signal between radio base station apparatuses of the plurality of radio networks. The plurality of network management means for instructing another wireless network to switch between an intra-network communication mode for performing normal intra-network communication and a transmission path state measurement mode for measuring the transmission path state of the wireless terminal device. Send a mode switching signal,
The wireless communication system according to claim 32, 33, or 34. The radio base station apparatus operating as the host station performs control to switch the communication mode of the other radio network from the intra-network communication mode to the transmission path state measurement mode by transmitting the mode switching signal, and has a plurality of directivities. A beam pattern is used to transmit a training signal known by the wireless terminal device of the other wireless network,
A wireless terminal apparatus that performs transmission path state measurement calculates transmission path state information for each directional beam pattern using a received signal and a known training signal, and transmits transmission path state information for each directional beam pattern. Notifying the wireless base station device of its own wireless network,
36. The wireless communication system according to claim 35. The channel state information may be received signal strength, received signal power to noise power ratio and / or carrier power to noise power ratio and / or carrier power to interference noise power ratio and / or received signal power to interference power ratio and / or Information including the received signal power to interference noise power ratio,
The wireless communication system according to claim 36. The radio base station apparatus operating as the host station includes an array antenna including a plurality of antenna elements, and transmits the mode switching signal to change the communication mode of the other radio network from the intra-network communication mode to the transmission path state. Perform control to switch to the measurement mode, and from the array antenna, for each antenna element or beam, transmit a training signal known by the wireless terminal device of other wireless network,
A wireless terminal apparatus that performs transmission path state measurement calculates transmission path state information for each antenna element or for each beam using a received signal and a known training signal, and transmits the transmission path state for each antenna element or for each beam. Notifying the state information to the wireless base station device of the own wireless network,
36. The wireless communication system according to claim 35.   The wireless communication system according to claim 38, wherein the transmission path state information is CSI.   40. The radio communication system according to claim 38 or 39, wherein the transmission path state information includes antenna information or beam information. The plurality of network management means, as directional beam control, calculate the antenna weight of each antenna element, or select the antenna weight from the code book,
41. The wireless communication system according to any one of claims 38 to 40, wherein:   The wireless communication system according to any one of claims 35 to 41, wherein the communication mode switching is performed at a predetermined time period.   The radio communication system according to any one of claims 35 to 41, wherein the communication mode switching is performed at an arbitrary time timing. A wireless communication system comprising a plurality of wireless networks including a wireless base station device and a plurality of wireless terminal devices each including an antenna capable of directivity control, and a control device capable of communicating with each wireless base station device,
The wireless base station device
MAC control means for performing directional beam control within the own wireless network;
Own radio network management means for managing directional beam information of the own radio network obtained from the MAC control means;
With
The control device includes:
Radio base station apparatus between the same radio base station apparatus and the same radio terminal apparatus regarding directional beam information obtained from all radio networks and transmission path states of radio terminal apparatuses in all radio networks obtained from all radio networks A plurality of network management means for managing a plurality of transmission path state information for signals transmitted to the wireless terminal device under different conditions ;
With
The plurality of network management means uses the transmission path state information to instruct all wireless networks about directional beam control.
A wireless communication system.   45. The radio communication system according to claim 44, wherein control timing synchronization of each radio base station apparatus is established by the control apparatus transmitting a synchronization signal and each radio base station apparatus receiving the synchronization signal. . The control device instructs the plurality of wireless networks to switch between an intra-network communication mode for performing normal intra-network communication and a transmission path state measurement mode for measuring the transmission path state of the wireless terminal device. Send a mode switching signal,
46. The wireless communication system according to claim 44 or 45. The control device performs control to switch the communication mode of all wireless networks from the intra-network communication mode to the transmission path state measurement mode by transmitting the mode switching signal,
The wireless base station device of all wireless networks uses a plurality of directional beam patterns to transmit a training signal known to wireless terminal devices of other wireless networks,
A wireless terminal apparatus that performs transmission path state measurement calculates transmission path state information for each directional beam pattern using a received signal and a known training signal, and transmits transmission path state information for each directional beam pattern. Notifying the wireless base station device of its own wireless network,
The wireless communication system according to claim 46, wherein: The channel state information may be received signal strength, received signal power to noise power ratio and / or carrier power to noise power ratio and / or carrier power to interference noise power ratio and / or received signal power to interference power ratio and / or Information including the received signal power to interference noise power ratio,
48. The wireless communication system according to claim 47. The control device performs control to switch the communication mode of all wireless networks from the intra-network communication mode to the transmission path state measurement mode by transmitting the mode switching signal,
The radio base station apparatus of all radio networks is provided with an array antenna including a plurality of antenna elements, and a training signal known by the radio terminal apparatus of another radio network is transmitted from the array antenna for each antenna element or for each beam. Send
A wireless terminal apparatus that performs transmission path state measurement calculates transmission path state information for each antenna element or for each beam using a received signal and a known training signal, and transmits the transmission path state for each antenna element or for each beam. Notifying the state information to the wireless base station device of the own wireless network,
The wireless communication system according to claim 46, wherein:   The wireless communication system according to claim 49, wherein the transmission path state information is CSI.   51. The wireless communication system according to claim 49 or 50, wherein the transmission path state information includes antenna information or beam information. The plurality of network management means, as directional beam control, calculate the antenna weight of each antenna element, or select the antenna weight from the code book,
52. The wireless communication system according to any one of claims 49 to 51, wherein:   The wireless communication system according to any one of claims 46 to 52, wherein the communication mode switching is performed at a predetermined time period.   53. The radio communication system according to any one of claims 46 to 52, wherein the communication mode switching is performed at an arbitrary time timing. A radio base station apparatus used in a radio communication system comprising a plurality of radio networks including a radio base station apparatus and a plurality of radio terminal apparatuses, wherein one of the radio base station apparatuses is a host station,
An antenna that can control directivity;
MAC control means for performing directional beam control within the own wireless network;
Directional beam information of the own radio network obtained from the MAC control means, directional beam information obtained from the other radio network, and transmission of radio terminal apparatuses in all radio networks obtained from the own radio network and the other radio network A plurality of network management means for managing a plurality of transmission path state information for signals transmitted to the wireless terminal device under different conditions between the same wireless base station device and the same wireless terminal device, regarding the path state; ,
A radio base station apparatus comprising: The plurality of network management means uses the transmission path state information to instruct the MAC control means and the other wireless network about directional beam control.
56. The radio base station apparatus according to claim 55. Provide an array antenna including a plurality of antenna elements,
The plurality of network management means, as directional beam control, calculate the antenna weight of each antenna element, or select the antenna weight from the code book,
57. The radio base station apparatus according to claim 55 or 56. A control apparatus for controlling a radio communication system including a plurality of radio networks including a radio base station apparatus including a directivity-controllable antenna and a plurality of radio terminal apparatuses,
Radio base station apparatus between the same radio base station apparatus and the same radio terminal apparatus regarding directional beam information obtained from all radio networks and transmission path states of radio terminal apparatuses in all radio networks obtained from all radio networks A plurality of network management means for managing a plurality of transmission path state information for signals transmitted to the wireless terminal device under different conditions ;
A control device comprising: The plurality of network management means uses the transmission path state information to instruct all wireless networks about directional beam control.
59. The control device according to claim 58. The radio base station apparatus includes an array antenna including a plurality of antenna elements,
The plurality of network management means, as directional beam control, calculate the antenna weight of each antenna element, or select the antenna weight from the code book,
60. The control device according to claim 58 or 59. A wireless terminal device used in the wireless communication system according to claim 36 or 47,
Using reception signals and known training signals, calculate transmission path state information for each directional beam pattern, and notify the wireless base station apparatus of the own wireless network of transmission path state information for each directional beam pattern.
A wireless terminal device. A radio terminal apparatus used in the radio communication system according to claim 38 or 49,
Calculate transmission path state information for each antenna element or beam using the received signal and a known training signal, and notify the wireless base station apparatus of the own wireless network of the transmission path state information for each antenna element or beam. To
A wireless terminal device.

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