JP5439276B2 - Radio base station apparatus and radio control apparatus - Google Patents

Description

  Embodiments described herein relate generally to a radio base station apparatus and a radio control apparatus that perform radio communication with a mobile station.

  2. Description of the Related Art In recent years, mobile radio communication systems have been advanced and speeded up, and studies have been conducted on the realization of radio communication having a theoretical speed exceeding 100 Mbps in communication systems such as WiMAX, LTE, and XGP systems. As a technology for realizing high-speed wireless communication, there is a MIMO (Multiple Input Multiple Output) technology in which a base station has a plurality of antennas and performs communication multiplexing with a terminal by performing spatial multiplexing. Application to the next generation mobile radio communication system is being studied.

Special table 2007-52559 gazette JP 2007-151167 A JP 2002-95031 A

  However, MIMO is expected to improve the speed at the center of the cell, but communication degradation near the cell edge has been a problem.

  An object of the present embodiment is to provide a radio base station apparatus and a radio control apparatus that can improve the communication quality of terminals near the cell edge.

  The radio base station apparatus according to the present embodiment is a radio base station apparatus that performs radio communication with a terminal, includes a plurality of antennas, and a plurality of radio units that transmit and receive radio signals by the plurality of antennas; Measuring means for measuring the received power of the uplink signal from the terminal for each antenna, and selecting means for selecting a combination of antennas used for wireless communication with the terminal based on the measurement result of the received power And signal processing means for performing communication control of the plurality of radio units according to the combination of the antennas.

  The radio control apparatus according to the present embodiment is a radio control apparatus that controls a plurality of radio apparatuses that transmit and receive radio signals to and from a terminal using a plurality of antennas, and that receives received power of an uplink signal from the terminal. Measuring means for measuring each antenna; selection means for selecting a combination of antennas used for wireless communication with the terminal based on the measurement result of the received power; and the plurality of radios according to the combination of antennas And signal processing means for performing communication control of the units.

The block diagram of a radio | wireless system provided with the radio base station apparatus which concerns on 1st Embodiment. The block diagram which shows the structure of the wireless base station apparatus which concerns on 1st Embodiment. The figure which shows the example of reception power measurement of an uplink signal. The figure which shows an example of receiving power aggregation information. The figure which shows the macro diversity availability determination in 1st Embodiment. The figure which shows the selection process of the macro diversity use antenna in 1st Embodiment. The figure which shows the macro diversity communication in 1st Embodiment. The figure which shows the macro diversity communication start sequence in 1st Embodiment. The block diagram which shows the structure of the wireless base station apparatus which concerns on 2nd Embodiment. The figure which shows the macro diversity availability determination in 2nd Embodiment. The figure which shows the selection process of the macro diversity use antenna in 2nd Embodiment. The figure which shows the macro diversity communication start sequence in 2nd Embodiment.

  Hereinafter, the radio base station apparatus according to the present embodiment will be described with reference to the drawings.

(First embodiment)
FIG. 1 is a configuration diagram of a radio system including a radio base station apparatus according to the first embodiment.

  In FIG. 1, an IP network / public communication network NW is connected to the gateway device GW, and a plurality of radio base station devices BS1 and BS2 are connected to the gateway device GW. The radio base station apparatus BS1 includes a plurality of radio units R11 to R1n that perform radio transmission and reception, and a radio control apparatus G1 that performs radio signal processing and signal distribution. Wireless terminal devices MS11 to MS1m such as PCs equipped with wireless terminals or wireless communication data cards perform voice or data communication with the wireless units R11 to R1n. Each of the radio units R11 to R1n includes a plurality of antennas, and can adjust the transmission power of the plurality of antennas to give directivity to the downlink signal. Similarly to the radio base station apparatus BS1, the radio base station apparatus BS2 includes a radio control apparatus G2 and a plurality of radio units R21 to R2n that perform radio communication with the radio terminal apparatus.

  FIG. 2 is a block diagram illustrating an example of a configuration of the radio base station apparatus. Below, radio base station apparatus BS1 is demonstrated as a representative.

  In FIG. 2, the gateway device GW is connected to an IP network / public communication network NW and a radio control device G1, and the radio control device G1 and a plurality of radio units R11 and R12 are connected by wires such as optical fibers. The wireless unit R11 is provided with a plurality of antennas AN11 to AN1n for wireless communication with the wireless terminal devices MS11 and MS12. Similarly, the wireless unit R12 is also provided with a plurality of antennas AN21 to AN2n for wireless communication.

  The wireless terminal devices MS11 and MS12 and the wireless units R11 and R12 are provided with a wireless communication unit 101, and the wireless terminal devices MS11 and MS12 perform wireless communication with one or more wireless units by the wireless communication unit 101. The wireless control device G1 includes a signal distribution unit 102 that distributes data received from the gateway device GW to the wireless units R11 and R12 that perform wireless communication with the wireless terminal devices MS1 and MS2, and signal processing that performs control related to wireless communication. Part 103 is provided.

  The signal processing unit 103 has a role of controlling the signal processing of the radio units R11 and R12. Here, a plurality of signal processing units 1031 and 1032 are provided according to the number of radio units R11 and R12. However, the present invention is not limited to this, and one signal processing unit 103 can control a plurality of radio units, and the number of radio units and the number of signal processing units are allowed to be different values.

  Radio control apparatus G1 transmits uplink data from radio terminal apparatuses MS1 and MS2 received via radio sections R11 and R12 to IP network / public communication network NW via gateway apparatus GW. Also, downlink data received from the IP network / public communication network NW via the gateway device GW is distributed to an appropriate radio unit by the signal distribution unit 102, and the radio terminal devices MS11, MS12 are transmitted via the radio units R11, R12. Send to.

  Further, the radio control apparatus G1 includes a received power measuring unit 104 that measures the received power of uplink signals from the radio terminal apparatuses MS1 and MS2, and received power aggregation information obtained by aggregating received power information measured by the received power measuring unit 104. And an antenna selection unit 106 that selects an antenna to be used for wireless communication between the wireless terminal devices MS1 and MS2 based on the received power aggregation information. The antenna selection unit 106 can arbitrarily select a combination of antennas used for radio communication with the radio terminal apparatuses MS1 and MS2 from the antennas AN11 to AN1n of the radio unit R11 and the antennas AN21 to AN2n of the radio unit R12. is there.

  The operation of the radio network controller G1 configured as described above will be described below.

[Macro diversity control]
In this radio communication system, for example, in FIG. 2, radio terminal apparatuses MS11 and M12 exist near the edges of cells formed by radio units R11 and R12, respectively, and communication by MIMO diversity via any one radio unit is performed. Becomes difficult, it shifts to macro diversity communication via a plurality of radio units R11 and R12. In the macro diversity communication between the radio terminal devices MS1 and MS2 and the radio units R11 and R12, the radio unit control device G1 measures the received power of the uplink signal of the radio terminal devices MS1 and MS2, and the received power measurement result is obtained. This is realized by determining whether or not macro diversity is possible, and by determining transmission combinations and determining antenna combinations used for macro diversity when it is determined that macro diversity is possible. As described above, by improving the reception power of the terminal using the antennas of different radio units, it is possible to improve the deterioration of the communication quality of the terminal existing near the cell edge.

[Received power measurement processing]
FIG. 3 shows an example of the received power measurement process for the uplink signal of the wireless terminal device.

  In FIG. 3, a plurality of radio units R11 to R14 are connected to the radio network controller G1. The reception power measurement unit 104 of the radio network controller G1 measures the reception power of the uplink signal A11 transmitted from the radio terminal device MS11 in each radio unit R11 to R14. The measured received power information IN11 to 14 is stored in the received power information storage unit 105. The antenna selection unit 106 selects a combination of antennas for performing wireless communication with the MS 11 based on the reception power information IN11 to 14 stored in the reception power information storage unit 105. In the example of FIG. 3, each of the radio units R11 to R14 has a plurality of antennas AN11 to AN14, AN21 to 24, AN31 to 34, and AN41 to 44. Therefore, the received power measurement is performed for each radio communication antenna of each radio unit. To do. Although FIG. 3 shows an example in which the number of antennas is four, the number of antennas can be arbitrarily set depending on the radio communication system.

[Reception power measurement timing]
As an example of the reception power measurement timing, a case will be described in which the wireless terminal device MS11 is implemented at the time of new connection, at the time of handover, and at a fixed period during connection.

  When the wireless terminal device MS11 is a new terminal that starts a new connection, the reception power measurement unit 104 performs reception power measurement using the first link channel establishment request signal at the time of the new connection as the uplink signal A11 to be measured. . The link channel establishment request from the wireless terminal device MS11 is omni-transmitted using a control channel shared by a plurality of wireless units R11 to R14. When the antenna selection unit 106 determines that macro diversity is possible for the new terminal, the antenna selection unit 106 starts communication by macro diversity from the time when the base station apparatus accommodates the radio terminal apparatus MS11.

  When radio terminal apparatus MS11 is a terminal that is undergoing handover, received power measurement section 104 receives the first handover request signal that is omni-transmitted to surrounding base station apparatuses during handover as uplink signal A11 to be measured. Measure power. The handover request signal from the wireless terminal device MS11 is omni-transmitted using a control channel commonly used by a plurality of wireless units R11 to R14. If the antenna selection unit 106 determines that macro diversity is possible for the terminal being handed over, the antenna selection unit 106 starts communication by macro diversity after the handover is successful.

  When the wireless terminal device MS11 is a terminal connected to the base station device, the reception power measuring unit 104 determines the individual communication channel assigned to the wireless terminal device MS11 every fixed period T (seconds) from the connection. A test signal is transmitted using a part of the received signal as a received power measurement channel, and the received power is measured using the test signal as an uplink signal A11 to be measured. When it is determined that macro diversity is possible for the connected terminal, the antenna selection unit 106 starts communication by macro diversity immediately after the antenna is determined.

[Determining Macro Diversity]
FIG. 4 shows an example of received power aggregation information managed by the radio network controller G1.

  Here, it is assumed that the received power aggregation information is stored in the received power information storage unit 105. The reception power measurement unit 104 notifies the antenna selection unit 106 when the reception power information of each of the radio units R11 to R14 in FIG. The antenna selection unit 106 aggregates the received reception power information IN11 to IN14 and stores them in the reception power information storage unit 105 as reception power aggregation information. Further, when storing the received power information, the identification information of the corresponding radio unit and the identification information of the antenna are stored in association with each received power information, and sorting by the received power is performed.

  FIG. 5 shows an example of macro diversity use antenna selection using received power aggregation information.

  Received power threshold information R is set in advance in the antenna selection unit 106 of the radio network controller G1, and the availability of macro diversity is determined using the received power aggregate information and the received power threshold information R. FIG. 5 shows an example of handover feasibility determination when the received power threshold information R = 50 dB.

  The antenna selection unit 106 of the radio control apparatus G1 refers to the received power aggregation information, and determines an antenna whose received power of the uplink signal from the radio terminal apparatus MS11 is larger than the received power threshold information R as a macro diversity candidate antenna. When there are a plurality of antennas determined as macro diversity candidate antennas, the wireless terminal apparatus determines that macro diversity is possible and selects a macro diversity use antenna.

[Select antenna for macro diversity]
FIG. 6 shows an example of macro diversity use antenna selection using received power aggregation information.

  An upper limit value M of the number of antennas capable of macro diversity is set in the antenna selection unit 106 of the radio control device G1 in advance, and is used when selecting a macro diversity use antenna. FIG. 6 shows an example of the case where the upper limit value M = 3 of the number of antennas capable of macro diversity, but the upper limit value M is the software / hardware specification of the wireless terminal device that implements macro diversity, and the software / hardware of the wireless unit. It is determined according to conditions such as the wear specifications and the adjacent state of the radio unit.

  When it is determined that macro diversity is possible, the antenna selection unit 106 of the radio control device G1 selects the top n macro diversity candidate antennas as the use antennas. At this time, the number n selected as the antenna to be used is the smaller one of the number of macro diversity candidate antennas and the upper limit value M of the number of antennas capable of macro diversity. The top n antenna combinations are not limited to the same radio unit, but can be freely selected. When the selected antenna used is composed of antennas of different radio units, macro diversity communication using a plurality of radio units is performed. When the selected antenna used is an antenna of the same radio unit, MIMO diversity communication is performed.

[Macro diversity communication control]
FIG. 7 shows an example of communication by macro diversity.

  The antenna selection unit 106 of the radio network controller G1 transmits a signal distribution change instruction to the signal distribution unit 102 when the antennas used based on the received power are different antennas R11 and R12, and the signal processing unit A use antenna change instruction is sent to 1031 and 1032 to start macro diversity communication. The signal distribution change instruction sends different radio unit information to which the used antenna belongs as a parameter, and the use antenna change instruction sends antenna information used for macro diversity as a parameter. The signal distribution unit 102 distributes downlink data for the corresponding terminal to the signal processing units 1031 and 1032 of the radio units R11 and R12 to which the antenna belongs based on a plurality of pieces of radio unit information included in the signal distribution change instruction. Send. Further, the signal processing units 1031 and 1032 control the downlink transmission power of each antenna for the radio units R11 and R12 used for macro diversity based on the antenna information included in the antenna change instruction, and the antenna selection unit 106 selects Transmission to the wireless terminal device MS11 is performed only from the used antenna.

[Communication sequence]
FIG. 8 is an example of a sequence of macro diversity communication with the wireless terminal device.

  In the example of FIG. 8, the wireless terminal device MS11, the wireless units R11 to 1n, the received power measuring unit 104, the signal processing units 1031 to 103n, and the signal distributing unit in the wireless control device G1 that performs centralized control of the wireless units R11 to 1n. 102 and the operation procedure of the antenna selection unit 106 are shown.

  Radio control apparatus G1 uses received power measurement section 104 to measure the received power of radio terminal apparatus MS11 using the received power measurement timing as a trigger (step S101). The received power measurement timing is performed at the time of new connection of the terminal, at the time of handover of the terminal, and every fixed period T during connection. Note that it is possible to simultaneously measure the received power of a plurality of terminals by using different channels for each terminal. The reception power measurement unit 104 notifies the reception power measurement result to the antenna selection unit 106 of the radio network controller G1 as a reception power notification (step S102).

  The antenna selection unit 106 stores the received power notification as received power aggregated information in the received power information storage unit 105, and determines whether or not macro diversity is possible (step S103). If the antenna selection unit 106 determines that macro diversity is possible as a result of this determination, the antenna selection unit 206 continues to select an antenna to be used for macro diversity (step S104). The antenna selection unit 106 sends a signal distribution change instruction (step S105) to the signal distribution unit 102 based on the selected antenna information. Based on the parameter information of the signal distribution change instruction, the signal distribution unit 102 distributes the downlink data to the wireless terminal device MS11 to the appropriate signal processing unit 103 and starts transmission. In addition, the antenna selection unit 106 transmits a use antenna change instruction (step S106) to the plurality of signal processing units 103 that control the radio units R11 to 1n to which the antenna selected as the macro diversity use antenna belongs. Based on the parameter information of the use antenna change instruction, the signal processing unit 103 controls the downlink signal transmission power related to the antennas of the corresponding radio units R11 to 1n and starts macro diversity communication (step S107).

  Note that the timing at which the signal distribution change instruction (step S105) and the used antenna change instruction (step S106) are sent differs depending on the received power measurement timing. When the wireless terminal device MS11 is newly connected, after the terminal connection processing is completed, a use antenna change instruction is transmitted to start macro diversity communication. When the wireless terminal device MS11 is undergoing a handover, a use antenna change instruction is transmitted after the handover process is completed, and macro diversity communication is started. When the wireless terminal device MS11 is connected and when the predetermined period T expires, the use antenna change instruction is immediately transmitted to start macro diversity communication. Further, when it is determined that the macro diversity communication that has been performed until now is not possible, the signal distribution is stopped by the signal distribution change instruction (step S105), and the use antenna change instruction (step S106) is performed. It is also possible to stop macro diversity communication by stopping the use of multiple antennas.

  Note that the start sequence of macro diversity communication is not limited to the above sequence.

(Second Embodiment)
FIG. 9 is a block diagram illustrating a configuration example of a radio base station apparatus according to the second embodiment. Note that the configuration of the wireless system according to the second embodiment is the same as that of the first embodiment. The same components as those in the first embodiment are denoted by the same reference numerals, and redundant description will be made only when necessary.

  In FIG. 9, a gateway device GW is connected to an IP network / public communication network NW and a radio control device G2, and the radio control device G1 and a plurality of radio units R11 and R12 are connected by wires such as optical fibers. The wireless unit R11 is provided with a plurality of antennas AN11 to AN1n for wireless communication with the wireless terminal devices MS11 and MS12. Similarly, the wireless unit R12 is also provided with a plurality of antennas AN21 to AN2n for wireless communication.

  The wireless terminals MS11 and MS12 and the wireless units R11 and R12 are provided with a wireless communication unit 201. The wireless terminal devices MS11 and MS12 perform wireless communication with one or more wireless units by the wireless communication unit 201. The wireless control device G1 includes a signal distribution unit 202 that distributes data received from the gateway device GW to wireless units R11 and R12 that perform wireless communication with the wireless terminal devices MS1 and MS2, and signal processing that performs control related to wireless communication. A unit 203 is provided. The radio network controller G1 transmits uplink data from the radio terminal devices MS1 and MS2 received via the radio units R11 and R12 to the IP network / public network NW via the gateway device GW. Also, downlink data received from the IP network / public network NW received via the gateway device GW is distributed to an appropriate radio unit by the signal distribution unit 202, and to the radio terminal devices MS11 and MS12 via the radio units R11 and R12. Send.

  Further, the radio units R11 and R12 are provided with a received power measuring unit 204 that measures the received power of uplink signals from the radio terminal devices MS1 and MS2, and the radio control device G1 receives the reception measured by the received power measuring unit 204. A received power information storage unit 205 that stores received power aggregated information obtained by aggregating power information, and an antenna selection unit 206 that selects a wireless communication antenna to be used for communication with a wireless terminal device based on the received power aggregated information. Provided.

  The operation of the radio network controller G1 configured as described above will be described below.

[Macro diversity control]
In the macro diversity communication between the radio terminal devices MS11 and MS12 and the radio units R11 and R12, the reception power of the uplink signals of the radio terminal devices MS11 and MS12 is measured in the radio units R11 and R12, and radio unit control is performed. The apparatus G1 determines whether or not macro diversity is possible based on the measurement result of the received power, and when it is determined that macro diversity is possible, the antenna combination used for macro diversity is determined and transmission control is performed.

[Received power measurement processing]
With reference to FIG. 3 described above, processing for measuring received power of an uplink signal from a wireless terminal device will be described.

  In FIG. 3, a plurality of radio units R11 to R14 are connected to the radio network controller G1. The reception power measurement unit 204 of the radio units R11 to R14 measures the reception power of the uplink signal A11 transmitted from the radio terminal apparatus MS11, and receives only the antenna information whose reception power is larger than the preset reception power threshold information R. Notify the antenna selection unit 206 of the wireless control device G1. In the example of FIG. 3, each of the radio units R11 to R14 has a plurality of antennas (AN11 to 14, AN21 to 24, AN31 to 34, AN41 to 44), and thus the received power measurement is performed on the antennas of the radio units R11 to R14. Do it every time. Although FIG. 3 shows an example in which the number of antennas is four, the number of antennas can be arbitrarily set depending on the radio communication system.

[Reception power measurement timing]
Since it is the same as that of the said 1st Embodiment, description is abbreviate | omitted.

[Determining Macro Diversity]
FIG. 10 shows an example of received power aggregation information managed by the radio network controller G1.

  When the received reception power information is stored in the reception power information storage unit 205 as reception power aggregate information, the antenna selection unit 206 associates the identification information of the radio unit corresponding to each reception power information with the identification information of the antenna. And sorting by received power. FIG. 10 shows an example of handover feasibility determination when the received power threshold information R = 50 dB.

  The antenna selection unit 206 determines all antennas included in the received power aggregation information as macro diversity candidate antennas. When the received power aggregation information includes a plurality of pieces of antenna information, the wireless terminal apparatus determines that macro diversity is possible and selects a macro diversity use antenna. When the macro diversity candidate antenna is a single antenna, it is determined that macro diversity is not possible, and communication using a single antenna is performed.

[Select antenna for macro diversity]
FIG. 11 shows an example of macro diversity use antenna selection using received power aggregation information.

  An upper limit value M of the number of antennas capable of macro diversity is set in advance in the antenna selection unit 206 of the radio network controller G1, and is used when selecting a macro diversity use antenna. FIG. 11 shows an example in which the upper limit value M = 3 of the number of antennas capable of macro diversity is shown. The upper limit value M indicates the software / hardware specifications of the wireless terminal device that implements macro diversity, and the software / hardware of the wireless unit. It is determined according to conditions such as the wear specifications and the adjacent state of the radio unit.

  When it is determined that the macro diversity is possible, the antenna selection unit 206 of the radio network controller G1 determines the top n of the macro diversity candidate antennas as the use antennas. At this time, the number n to be selected is the smaller one of the number of macro diversity candidate antennas and the upper limit M of the number of antennas capable of macro diversity. The top n antenna combinations are not limited to the same radio unit, but can be freely selected. When the selected antenna used is composed of antennas of different radio units, macro diversity communication using a plurality of radio units is performed. When the selected use antenna is an antenna of the same radio unit, MIMO communication is performed.

[Macro diversity communication control]
Since it is the same as that of the said 1st Embodiment, description is abbreviate | omitted.

[Communication sequence]
FIG. 12 is an example of a sequence of macro diversity communication with a wireless terminal device.

  In the example of FIG. 12, the radio terminal device MS11, the radio units R11 to 1n, the signal processing units 2031 to 203n, the signal distribution unit 202, and the antenna selection unit in the radio control device G1 that collectively controls the radio units R11 to 1n. The operation procedure 206 is shown.

  In the radio units R11 to 1n, the received power of the wireless terminal device MS11 is measured with the received power measurement timing as a trigger (step S201). The received power measurement timing is performed at the time of new connection of the terminal, at the time of handover of the terminal, and every fixed period T during connection. Note that it is possible to simultaneously measure the received power of a plurality of terminals by using different channels for each terminal. The radio units R11 to n1 notify the reception power measurement result to the antenna selection unit 206 of the radio network controller G1 as a received power notification (step S202).

  The antenna selection unit 206 stores the received power notification as received power aggregated information in the received power information storage unit 205, and determines whether macro diversity is possible (step S203). As a result of the determination, if it is determined that macro diversity is possible, the antenna selection unit 206 continues to select an antenna to be used for macro diversity (step S204). The antenna selection unit 206 sends a signal distribution change instruction (step S205) to the signal distribution unit 202 based on the selected antenna information. Based on the parameter information of the signal distribution change instruction, the signal distribution unit 202 distributes the downlink data to the wireless terminal device MS11 to the appropriate signal processing unit 103 and starts transmission. In addition, the antenna selection unit 106 transmits a use antenna change instruction (step S206) to the plurality of signal processing units 103 that control the radio units R11 to 1n to which the antenna selected as the macro diversity use antenna belongs. Based on the parameter information of the use antenna change instruction, the signal processing unit 103 controls the downlink signal transmission power related to the antennas of the corresponding radio units R11 to 1n to start macro diversity communication (step S207).

  Note that the timing for sending the signal distribution change instruction (step S205) and the antenna used change instruction (step S206) differs depending on the received power measurement timing. When the wireless terminal device MS11 is newly connected, after the terminal connection processing is completed, a use antenna change instruction is transmitted to start macro diversity communication. When the terminal is undergoing handover, a use antenna change instruction is transmitted after the handover process is completed, and macro diversity communication is started. When the fixed period T during connection has expired, an antenna change instruction is immediately transmitted to start macro diversity communication. Also, if it is determined that the wireless terminal device that has been performing macro diversity communication so far cannot perform macro diversity communication, the signal distribution is stopped by the signal distribution change instruction (step S205), and the use antenna change instruction (step S206). It is also possible to stop macro diversity communication by stopping the use of multiple antennas.

  Note that the start sequence of macro diversity communication is not limited to the above sequence.

  As described above, in the first and second embodiments, the received power of the uplink signal is measured for each antenna of the plurality of radio units, and the optimum for macro diversity communication with the terminal is based on the measurement result. An antenna selection method that determines a combination of antennas is realized. In conventional MIMO, antenna selection, which is limited to only within the same base station, is extended between different radio units at a great distance, giving flexibility to antenna combinations that have been limited in a narrow range so far. It is possible to have it. As a result, it is possible to improve the gain of the terminal existing in the vicinity of the cell edge and improve the radio communication quality.

  Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. In addition, various inventions can be formed by appropriately combining a plurality of components disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, constituent elements over different embodiments may be appropriately combined.

  G1, G2 ... Radio control device, R11-R1n, R21-R2n ... Radio unit, MS11-MS1m, MS21-MS2m ... Radio terminal device, GW ... Gateway device, NW ... IP network / public communication network, AN11-1n, AN21 ˜AN2n: antenna for wireless communication, 101, 201: wireless communication unit, 102, 202 ... signal distribution unit, 103, 203 ... signal processing unit, 104, 204 ... received power measuring unit, 105, 205 ... received power information storage unit , 106, 206... Antenna selection unit.

Claims (13)

A wireless base station device that performs wireless communication with a terminal,
A plurality of radio units comprising a plurality of antennas, and transmitting and receiving radio signals by the plurality of antennas;
Measuring means for measuring the received power of the uplink signal from the terminal omni-transmitted on the control channel for each antenna;
Selection means for selecting a combination of antennas used for wireless communication with the terminal based on the measurement result of the received power;
Signal processing means for performing communication control of the plurality of radio units according to the combination of the antennas ,
The selection unit compares the measurement result of the received power with a predetermined threshold value, determines that macro diversity is possible when there are a plurality of antennas having received power equal to or higher than the threshold value, and performs radio communication with the terminal. A radio base station apparatus characterized in that the number of antennas to be selected as a combination of antennas used for communication is the smaller of a predetermined upper limit of the number of antennas and the number of antennas equal to or greater than the threshold .   The radio base station apparatus according to claim 1, wherein the measurement unit is provided for each radio unit.   The radio base station apparatus according to claim 1 or 2, wherein the uplink signal includes a link establishment message that is omni-transmitted by the control channel from the terminal.   The radio base station apparatus according to claim 1 or 2, wherein the uplink signal includes a handover request message that is omni-transmitted from the terminal through a control channel. It said selection means, the radio base station apparatus according to claim 1, characterized in that to allow arbitrarily changing the threshold value. When it is determined that the macro diversity is possible, the selection unit selects an antenna to be used for wireless communication with the terminal from an antenna having a reception power equal to or higher than the threshold in descending order of reception power. The radio base station apparatus according to claim 1 , wherein the radio base station apparatus is selected. Said selection means, the radio base station apparatus according to claim 1, characterized in that the arbitrarily changing the upper limit value. A wireless control device that controls a plurality of wireless devices that transmit and receive wireless signals with a plurality of antennas to and from a terminal,
Measuring means for measuring the received power of the uplink signal from the terminal omni-transmitted on the control channel for each antenna;
Selection means for selecting a combination of antennas used for wireless communication with the terminal based on the measurement result of the received power;
Signal processing means for performing communication control of the plurality of wireless devices according to the combination of the antennas ,
The selection unit compares the measurement result of the received power with a predetermined threshold value, determines that macro diversity is possible when there are a plurality of antennas having received power equal to or higher than the threshold value, and performs radio communication with the terminal. A radio control apparatus characterized in that the number of antennas to be selected as a combination of antennas used for communication is the smaller of a predetermined upper limit of the number of antennas and the number of antennas equal to or greater than the threshold . The radio control apparatus according to claim 8 , wherein the uplink signal includes a link establishment message that is omni-transmitted from the terminal through a control channel. The radio control apparatus according to claim 8 , wherein the uplink signal includes a handover request message that is omni-transmitted from the terminal through a control channel. The radio control apparatus according to claim 8 , wherein the selection unit can arbitrarily change the threshold value. When it is determined that the macro diversity is possible, the selection unit selects an antenna to be used for wireless communication with the terminal from an antenna having a reception power equal to or higher than the threshold in descending order of reception power. The radio control apparatus according to claim 8 , wherein the radio control apparatus is selected. The radio control apparatus according to claim 8 , wherein the selection unit can arbitrarily change the upper limit value.

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