JP6509758B2 - Wireless base station using directivity switching antenna and antenna directivity switching method - Google Patents

Description

  The present invention is a multicast that transmits the same wireless signal to a plurality of wireless terminals in a wireless base station that performs wireless communication by sharing the same frequency band with one or more wireless terminals using a plurality of directivity switching antennas. Communication, or unicast communication that transmits / receives one wireless terminal or one wireless signal or single user MIMO (SU-MIMO) signal to / from one wireless terminal, or MU that transmits / receives multi-user MIMO (MU-MIMO) signals to / from multiple wireless terminals The present invention relates to a wireless base station using a directivity switching antenna and an antenna directivity switching method using a directivity switching antenna which selects an optimal antenna directivity for each of a plurality of directivity switching antennas for MIMO communication.

  In recent years, with the spread of portable high-performance wireless terminals such as notebook computers and smartphones, wireless LANs of the IEEE 802.11 standard have been widely used not only in businesses and public spaces but also in general homes. The wireless LANs of the IEEE 802.11 standard include a wireless LAN of the IEEE 802.11b / g / n standard which uses the 2.4 GHz band and a wireless LAN of the IEEE 802.11 a / n / ac standard which uses the 5 GHz band.

  In a wireless LAN of the IEEE 802.11b standard or the IEEE 802.11g standard, 13 channels are prepared at intervals of 5 MHz between 2400 MHz and 2483.5 MHz. However, when using multiple channels at the same place, it is possible to simultaneously use up to three channels or even up to four channels at the same time by using channels so that spectra do not overlap to avoid interference.

  In the case of the wireless LAN of the IEEE 802.11a standard, in Japan, a total of 19 channels of 8 channels and 11 channels not overlapping with each other are defined between 5170 MHz and 5330 MHz and between 5490 MHz and 5710 MHz. In the IEEE 802.11a standard, the bandwidth per channel is fixed at 20 MHz.

  The maximum transmission rate of the wireless LAN is 11 Mbps in the case of the IEEE 802.11b standard, and 54 Mbps in the case of the IEEE 802.11a standard and the IEEE 802.11g standard. However, the transmission rate here is the transmission rate on the physical layer. Actually, since the transmission efficiency at the MAC (Medium Access Control) layer is about 50 to 70%, the upper limit of the actual throughput is about 5 Mbps in the IEEE 802.11b standard, and 30 Mbps in the IEEE 802.11a standard or the IEEE 802.11g standard It is an extent. In addition, the transmission rate is further reduced as the number of wireless base stations and wireless terminals that try to transmit information increases.

  Therefore, in the IEEE 802.11n standard, which was standardized in 2009, the channel bandwidth, which has been fixed at 20 MHz, is expanded to 40 MHz at the maximum, and in addition, MIMO (Multiple input multiple output) technology Implementation was decided. If transmission and reception are performed by applying all the functions defined in the IEEE802.11n standard, it is possible to realize a communication speed of up to 600 Mbps in the physical layer.

  Furthermore, in the IEEE 802.11 ac standard, which has been standardized in 2013, a MU-MIMO transmission method that extends the channel bandwidth to 80 MHz or up to 160 MHz, or applies Space Division Multiple Access (SDMA). It is decided to introduce When transmission and reception are performed by applying all the functions defined in the IEEE 802.11ac standard, the physical layer can realize a communication speed of up to about 6.9 Gbps.

  In addition to the above-mentioned standardization technology, a wireless base station is equipped with a directivity switching antenna capable of switching antenna directivity, and studies are underway to optimize the antenna directivity according to the reception situation of the wireless terminal ( Non-patent documents 1, 2). By this means, it is possible to improve the communication speed by improving the received power at the wireless terminal.

Lopez, Alfred R. "Performance predictions for cellular switched-beam intelligent antenna systems." Communications Magazine, IEEE 34.10 (1996): 152-154. Li, Yingjie, Martin J. Feuerstein, and Douglas O. Reudink. "Performance evaluation of a cellular base station multibeam antenna." Vehicular Technology, IEEE Transactions on 46.1 (1997): 1-9.

  By the way, in wireless LAN, wireless communication is performed using various communication modes, such as SU-MIMO communication and MU-MIMO communication. Here, SU-MIMO communication transmits one radio signal to one radio terminal, and MU-MIMO communication transmits different radio signals for each radio terminal, and in addition, a beacon signal or the like for a radio LAN As such, a form in which the same wireless signal is transmitted by multicast is also used. In order to improve the communication quality in each communication mode, it is necessary to take measures according to each communication mode.

  Also, as one of the methods for improving communication quality, there is a method of using a directivity switching antenna as described above, but in a configuration using a plurality of directivity switching antennas, various communication modes may be used for each directivity switching antenna. There is no study on switching control of combined antenna directivity.

  The present invention is a wireless base station that performs wireless communication by sharing the same frequency band with one or more wireless terminals using a plurality of directivity switching antennas, and performs multicast communication, unicast communication, MU for each directivity switching antenna. -It aims at providing a wireless base station and antenna directivity switching method using a directivity switching antenna that can switch antenna directivity that is optimal for MIMO communication.

  According to a first aspect of the present invention, there is provided a directivity switching antenna including a plurality of directivity switching antennas each of which can select one of a plurality of antenna directivity and performing radio communication by sharing the same frequency band with one or more wireless terminals. In the used radio base station, a multicast mode for transmitting the same radio signal to a plurality of radio terminals, or a unicast mode for transmitting and receiving one radio signal or SU-MIMO signal with one radio terminal, or A wireless signal processing unit that performs transmission / reception processing of a wireless signal according to an MU-MIMO mode that transmits / receives an MU-MIMO signal to / from a plurality of wireless terminals, a multicast mode, a unicast mode, or a MU-MIMO mode Antenna directivity switching control that performs control to select one antenna directivity for each of a plurality of directivity switching antennas accordingly Provided with a door.

  In the wireless base station using the directivity switching antenna according to the first invention, the antenna directivity switching control unit generally selects from among the antenna directivity that can be selected for each of a plurality of directivity switching antennas in the multicast mode. The antenna directivity is selected so as to obtain a wide range of antenna directivity.

  In the wireless base station using the directivity switching antenna according to the first aspect of the invention, the antenna directivity switching control unit selects an antenna directivity which can be selected for each of a plurality of directivity switching antennas in the unicast mode. The antenna directivity in which the received power or signal power to interference power ratio for the wireless terminal performing unicast communication is maximized is selected.

  In the wireless base station using the directivity switching antenna according to the first invention, the antenna directivity switching control unit selects an antenna directivity which can be selected for each of a plurality of directivity switching antennas in the MU-MIMO mode. It is a structure which respectively selects the antenna directivity which the sum total or minimum value of the signal electric power to interference power ratio with respect to each radio | wireless terminal used as the object of MU-MIMO communication becomes the largest.

  In the wireless base station using the directivity switching antenna of the first invention, the signal power in the antenna directivity selected for each of the plurality of directivity switching antennas for each of the multicast mode, unicast mode, and MU-MIMO mode Signal power adjusting means is provided for adjusting to a preset reference value.

  A second invention comprises a plurality of directivity switching antennas each of which can select one of a plurality of antenna directivity, and an antenna of a radio base station that performs radio communication by sharing the same frequency band with one or more radio terminals. In the directivity control method, the wireless signal processing unit transmits / receives one wireless signal or SU-MIMO signal to / from a multicast mode in which the same wireless signal is transmitted to a plurality of wireless terminals, or to one wireless terminal. Transmission / reception processing of a radio signal according to a MU-MIMO mode for transmitting / receiving a MU-MIMO signal to / from a plurality of radio terminals is performed in a unicast mode or a plurality of wireless terminals, and the antenna directivity switching control unit performs a multicast mode or a unicast Control for selecting one antenna directivity for each of a plurality of directivity switching antennas according to the mode or MU-MIMO mode Do.

  In the antenna directivity control method of a wireless base station according to the second aspect of the present invention, the antenna directivity switch control unit selects the plurality of antenna directivity selectable for each of a plurality of directivity switching antennas in the multicast mode. Each antenna directivity which can obtain a wide range of antenna directivity is selected.

  In the antenna directivity control method of a wireless base station according to the second aspect of the present invention, the antenna directivity switch control unit is configured to select from among the antenna directivity which can be selected for each of a plurality of directivity switching antennas in the unicast mode. The antenna directivity that maximizes the received power or the signal power to interference power ratio for the wireless terminal performing cast communication is selected respectively.

  In the antenna directivity control method of a wireless base station according to the second aspect of the present invention, the antenna directivity switch control unit selects an antenna directivity that can be selected for each of a plurality of directivity switching antennas in the MU-MIMO mode. The antenna directivity in which the total value or the minimum value of the signal power to interference power ratio for each wireless terminal to be subjected to the MU-MIMO communication is maximized is selected.

  In the antenna directivity control method of a wireless base station according to the second invention, the signal power in the antenna directivity selected for each of the plurality of directivity switching antennas in advance for each of the multicast mode, unicast mode, and MU-MIMO mode Adjust to the set reference value.

  According to the present invention, by switching the antenna directivity for each of a plurality of directivity switching antennas, a wide range of antenna directivity can be realized in the multicast mode to enable transmission to wireless terminals scattered in a wide range, and in the unicast mode Achieve antenna directivity to the destination wireless terminal to improve communication quality, and in MU-MIMO mode to achieve good overall antenna directivity to the plurality of destination wireless terminals to improve communication quality Can.

It is a figure which shows the structural example corresponding to Examples 1-3 of the wireless base station of this invention. It is a figure which shows the example of antenna directivity selection of a multicast mode. It is a figure which shows the example of antenna directivity selection of a unicast mode. It is a figure explaining the antenna directivity selection reference | standard of unicast mode by RSSI or SIR. It is a figure which shows the example of antenna directivity selection of MU-MIMO mode. It is a figure explaining the antenna directivity selection reference | standard of MU-MIMO mode by SIR. It is a figure which shows the structural example corresponding to Example 4 of the wireless base station of this invention. It is a figure which shows the example of signal power adjustment in Example 4 of the wireless base station of this invention.

FIG. 1 shows a configuration example corresponding to the first to third embodiments of the radio base station of the present invention.
In FIG. 1, the wireless base station 10 includes a wired interface 11, a communication mode switching unit 12, a wireless signal processing unit 13, a storage unit 14, an antenna directivity switching control unit 15, and directivity switching antennas 16-1 to 16-N ( N is an integer of 2 or more. Although the directivity switching antennas 16-1 to 16-N in the embodiments shown below each show an example in which selection of four antenna directivity d1 to d4 is possible, the direction of the switchable antenna directivity and the number of selection are It may be optional for each antenna. In the vicinity of the radio base station 10, radio terminals 20-1 to 20-M (M is an integer of 1 or more) are arranged.

  The wired interface 11 converts a signal input from the network into a signal that can be processed in the wireless base station, and outputs the converted signal to the communication mode switching unit 12 and the wireless signal processing unit 13. In addition, the signal input from the wireless signal processing unit 13 is converted into a signal that can be processed by the network, and the converted signal is output to the network.

  The communication mode switching unit 12 selects a communication mode corresponding to a signal input from the wired interface 11 or a signal generated in the wireless base station, and notifies the antenna switching control unit 15 of the selected communication mode. The communication mode is a multicast mode in which the radio base station 10 transmits the same radio signal (eg, beacon signal, control signal, video signal, etc.) to a plurality of radio terminals, and the radio base station 10 communicates with one radio terminal. The unicast mode in which one radio signal or SU-MIMO signal is transmitted and received, and the MU-MIMO mode in which the radio base station 10 transmits and receives an MU-MIMO signal to and from a plurality of radio terminals.

  The wireless signal processing unit 13 converts a signal input from the wired interface 11 or a signal generated in the wireless base station into a wireless signal corresponding to the communication mode, and transmits / receives the directivity switching antennas 16-1 to 16- from the transmission / reception terminals 1-N. Output to N. In the multicast mode, the same radio signal is output from the transmission / reception terminals 1 to N. In the unicast mode, the same radio signal or SU-MIMO signal addressed to one radio terminal is output from the transmission / reception terminals 1 to N. In the multicast mode, MU-MIMO signals addressed to a plurality of wireless terminals are output from the transmission / reception terminals 1 to N. Further, the wireless signal processing unit 13 performs reception processing on the wireless signals input to the transmission / reception terminals 1 to N in accordance with the communication mode, and outputs the received wireless signals to the wired interface 11. Furthermore, the received power information in each antenna directivity of each directivity switching antenna is acquired for each wireless terminal, and is output to the storage unit 14.

  The storage unit 14 lists and stores received power information in each antenna directivity of each directivity switching antenna for each wireless terminal. Further, the received power information is output to the communication mode switching unit 12 in accordance with the instruction from the communication mode switching unit 12.

  The antenna directivity switching control unit 15 performs control to select the antenna directivity in each directivity switching antenna based on the communication mode information input from the communication mode switching unit 12.

  The directivity switching antennas 16-1 to 16 -N set the antenna directivity corresponding to the communication mode selected by the antenna directivity switching control unit 15, and transmit and receive radio signals to and from the wireless terminal. Specific examples will be described as Examples 1 to 3 shown below.

Example 1
FIG. 2 shows an example of antenna directivity selection in the multicast mode.
In the multicast in the present invention, a radio base station having a plurality of directivity switching antennas is the same radio signal (for example, a beacon signal, a control signal, a video signal, etc.) to one or more radio terminals scattered widely in various places. Is sent.

  In FIG. 2, when the communication mode switching unit 12 detects a multicast mode from a signal input from the network or a signal generated in the wireless base station, the communication mode switching unit 12 notifies the antenna directivity switching control unit 15. The antenna directivity switching control unit 15 selects antenna directivity d1 to d that can be selected for each of the directivity switching antennas 16-1 to 16-N so that a wide range of antenna directivity can be obtained as a whole. For example, antenna directivity d1 to d4 are respectively selected in order with respect to directivity switching antennas 16-1 to 16-4.

  When the radio signal processing unit 13 generates one radio signal corresponding to the multicast mode, the one radio signal is selected from the directivity switching antennas 16-1 to 16-4 and has a wide range of antenna directivity in the whole. Will be sent. Thereby, multicast communication can be efficiently performed to the communication area formed by the directivity switching antennas 16-1 to 16-4, and the wireless terminals 20-1 to 20-M scattered widely can be received. .

  In addition, the overall antenna directivity selected by each directivity switching antenna for the multicast mode is the reception mode in which the radio base station receives the signal transmitted from the radio terminals scattered in a wide area, the presence or absence of the radio signal It can apply also to the sensing mode which detects. That is, when the wireless base station is in the reception mode or the sensing mode, a wide range of antenna directivity can be obtained from among the antenna directivity that can be selected for each of the directivity switching antennas 16-1 to 16-N. Select to

(Example 2)
FIG. 3 shows an example of antenna directivity selection in the unicast mode.
Unicast in the present invention is a form in which a wireless base station having a plurality of directivity switching antennas transmits one wireless signal or SU-MIMO signal to a destination wireless terminal. At this time, antenna directivity of each directivity switching antenna is selected so as to obtain good characteristics for the destination radio terminal. Here, it is assumed that the number N of directivity switching antennas is 4 and antenna directivity d1 to d4 is selected for each of directivity switching antennas 16-1 to 16-4.

  In FIG. 3, the communication mode switching unit 12 notifies the antenna directivity control unit 15 when it detects a unicast mode addressed to the wireless terminal 20-3 here from a signal input from the network. The antenna directivity switching control unit 15 receives the received power (RSSI) for the radio terminal 20-3 performing unicast communication from the antenna directivity d1 to d4 selectable for each of the directivity switching antennas 16-1 to 16-4. Or select the antenna directivity that maximizes the signal power to interference power ratio (SIR).

  Here, the wireless signal processing unit 13 acquires the RSSI in each of the antenna directivity d1 to d4 of the directivity switching antennas 16-1 to 16-4 for each of the wireless terminals 20-1 to 20-M, and obtains the SIR. They are found and listed and stored in the storage unit 14. An example list of RSSI and SIR for the wireless terminals 20-1 to 20-4 is shown in FIG. For example, for the radio terminal 20-1, the SIR in the antenna directivity d1 of the directivity switching antenna 16-1 uses the RSSI of the antenna directivity d1 as the desired signal, and the total RSSI of the antenna directivity d2 to d4 is It is a calculation result in the case where it is a ratio of the desired signal and an interference signal when it is set as an interference signal, or in the case where an electric power set in advance is set as an interference signal.

  In the example illustrated in FIG. 4, when the wireless base station 10 performs unicast communication with the wireless terminal 20-3, each of the antenna directivity d1 to d4 of the directivity switching antennas 16-1 to 16-4 in the wireless terminal 20-3. RSSI or SIR is referred to. Among the antenna directivity d1 to d4 selectable for each of the directivity switching antennas 16-1 to 16-4, the directivity switching antenna 16-1 is selected as an antenna directivity that maximizes the RSSI for the wireless terminal 20-3. The antenna directivity d4, d3, d2 and d2 are respectively selected for 16-4. Alternatively, antenna directivity d4, d3, d2, and d2 are selected for directivity switching antennas 16-1 to 16-4, respectively, as the antenna directivity that maximizes the SIR for wireless terminal 20-3. In addition, among antenna directivity which can be selected for each of directivity switching antennas 16-1 to 16-4, if there is one having the same maximum value of RSSI or SIR for wireless terminal 20-3, one of them can be arbitrarily selected. Be done.

  The wireless signal processing unit 13 generates one wireless signal corresponding to the unicast mode, or the wireless terminal 20-3 obtained for each antenna directivity of the directivity switching antennas 16-1 to 16-4. When the SU-MIMO signal is generated based on the propagation channel information, the one radio signal or SU-MIMO signal is transmitted with the antenna directivity selected from the directivity switching antennas 16-1 to 16-4, respectively. It is received by the wireless terminal 20-3. Thus, from among the antenna directivity which can be selected for each of the directivity switching antennas 16-1 to 16-4, the antenna directivity which maximizes the RSSI or SIR for the radio terminal 20-3 performing unicast communication is selected. Thus, the communication quality of the wireless terminal 20-3 performing unicast communication can be improved.

(Example 3)
FIG. 5 shows an example of antenna directivity selection in the MU-MIMO mode.
The MU-MIMO in the present invention is a form in which a radio base station having a plurality of directivity switching antennas transmits and receives an MU-MIMO signal for transmitting different information to a plurality of radio terminals. At this time, the antenna directivity of each directivity switching antenna is selected so as to obtain good characteristics as a whole for each wireless terminal to be subjected to MU-MIMO communication. Here, it is assumed that the number N of directivity switching antennas is 4 and antenna directivity d1 to d4 is selected for each of directivity switching antennas 16-1 to 16-4.

  In FIG. 5, when the communication mode switching unit 12 detects the MU-MIMO mode for the wireless terminals 20-1 to 20-4 from the signal input from the network, it notifies the antenna directivity switching control unit 15 here. The antenna directivity switching control unit 15 selects one of the antenna directivity d1 to d4 which can be selected for each of the directivity switching antennas 16-1 to 16-N as the wireless terminal 20-1 to 20 targeted for MU-MIMO communication. Select the antenna directivity that maximizes the sum or minimum value of SIR for -4.

  Here, among the lists of RSSI and SIR that the radio signal processing unit 13 makes a list and stores in the storage unit 14, an example for the radio terminals 20-1 to 20-4 which are targets of MU-MIMO communication is shown in FIG. . In addition, each numerical value is the same as that of FIG.

  In the example shown in FIG. 6, when the radio base station 10 performs MU-MIMO communication with the radio terminals 20-1 to 20-4, antenna directivity d1 selectable for each of the directivity switching antennas 16-1 to 16-4. The directivity switching antennas 16-1 to 16-4 have antenna directivity d3, d2 and d2 respectively as antenna directivity that maximizes the total value of SIR for the radio terminals 20-1 to 20-4 among , D2 are selected. Alternatively, as the antenna directivity in which the minimum value of the SIR for the radio terminals 20-1 to 20-4 is maximized, the directivity switching antennas 16-1 to 16-4 select the antenna directivity d3, d2, d2, and d2, respectively. Be done. Among the antenna directivity which can be selected for each of the directivity switching antennas 16-1 to 16-4, if there is the same maximum value of the sum or minimum value of the SIRs for the radio terminals 20-1 to 20-4. , One of which is arbitrarily selected.

  The wireless signal processing unit 13 generates an MU-MIMO signal based on propagation channel information with the wireless terminals 20-1 to 20-4 obtained for each antenna directivity of the directivity switching antennas 16-1 to 16-4. When generated, the MU-MIMO signal is transmitted with the antenna directivity selected from the directivity switching antennas 16-1 to 16-4, and is received by the destination radio terminals 20-1 to 20-4. Thus, from among the antenna directivity which can be selected for each of the directivity switching antennas 16-1 to 16-4, the total value of the SIRs for the radio terminals 20-1 to 20-4 to be subjected to MU-MIMO communication or The communication quality of the radio terminals 20-1 to 20-4 performing MU-MIMO communication can be improved by selecting the antenna directivity in which the minimum value is maximized.

(Example 4)
As shown in the first to third embodiments, the optimum antenna directivity is selected for each directivity switching antenna according to each communication mode, but in the fourth embodiment, signal power transmitted and received by each directivity switching antenna An example is shown in which the interference power is reduced by adjusting the signal according to each communication mode.

FIG. 7 shows a configuration example corresponding to Embodiment 4 of the radio base station of the present invention.
7, in addition to the configurations of the wireless base stations of the first to third embodiments shown in FIG. 1, the wireless base station of the fourth embodiment includes the transmission / reception terminals 1 to N of the wireless signal processing unit 13 and the directivity switching antenna. The signal power adjustment units 18-1 to 18-N, which adjust the signal power under the control of the signal power control unit 17, are connected between 16-1 to 16-N. The signal power control unit 17 sets a signal power adjustment value according to the information of the communication mode notified from the communication mode switching unit 12. An example is shown in FIG. The other configuration is the same as that of the radio base station of the first to third embodiments shown in FIG.

  In FIG. 8, antenna directivity for each of the directivity switching antennas 16-1 to 16-4 selected in the multicast mode of the first embodiment and RSSI for the radio terminals 20-1 to 20-4 for each of the antenna directivity. Indicates the minimum value of The antenna directivity for each of the directivity switching antennas 16-1 to 16-4 selected in the unicast mode of the second embodiment and the RSSI for the radio terminal 20-3 performing unicast communication with the antenna directivity are shown. Further, antenna directivity for each of the directivity switching antennas 16-1 to 16-4 selected in the MU-MIMO mode of the third embodiment is shown, and radio terminals 20-1 to MU-MIMO communication are performed for each of the antenna directivity. 20 shows the minimum value of RSSI for 20-4.

  The signal power control unit 17 notifies the signal power adjustment units 18-1 to 18-4 of a reference value set in advance for each communication mode. Here, the reference value for each communication mode is -70 dBm, but a different value may be used for each communication mode. According to the reference value for each communication mode notified from the signal power control unit 17, the signal power adjustment units 18-1 to 18-4 calculate the RSSI of the selected antenna and the adjustment value for the minimum value thereof. Signal power transmitted and received by the directivity switching antenna is adjusted based on the reference value.

  When only one of amplification and attenuation of the signal power can be performed, the upper limit value and the lower limit value of the signal power are provided as the reference value.

  The processes of the first to fourth embodiments described above are the communication mode switching unit 12, the wireless signal processing unit 13, the storage unit 14 and the antenna directivity switching control unit 15 shown in FIG. 1, and the signal power control shown in FIG. The program not only is realized by dedicated hardware but also a program for realizing each function is recorded in a computer readable recording medium, and the program recorded in the recording medium is read by a computer and executed. Can be realized by In addition to recording the program on a recording medium, the program can also be provided through a network.

DESCRIPTION OF REFERENCE NUMERALS 10 wireless base station 11 wired interface 12 communication mode switching unit 13 wireless signal processing unit 14 storage unit 15 antenna directivity switching control unit 16-1 to 16-N directivity switching antenna 17 signal power control unit 18-1 to 18-N Signal power adjustment unit 20-1 to 20-M wireless terminal

Claims (10)

A wireless base station using a directivity switching antenna that includes a plurality of directivity switching antennas that can select one of a plurality of antenna directivity and performs radio communication by sharing the same frequency band with one or more wireless terminals ,
A multicast mode for transmitting the same radio signal to a plurality of the wireless terminals, a unicast mode for transmitting and receiving one radio signal or SU-MIMO signal with one wireless terminal, or a plurality of the radios A radio signal processing unit that performs transmission and reception processing of a radio signal according to an MU-MIMO mode that transmits and receives an MU-MIMO signal to and from a terminal;
An antenna directivity switching control unit that performs control to select one antenna directivity for each of the plurality of directivity switching antennas according to the multicast mode, the unicast mode, or the MU-MIMO mode A radio base station using a directivity switching antenna characterized by the invention. In a radio base station using the directivity switching antenna according to claim 1,
The antenna directivity switching control unit is configured to select, from the antenna directivity that can be selected for each of the plurality of directivity switching antennas in the multicast mode, antenna directivity that can obtain antenna directivity in a wide range as a whole. A radio base station using a directivity switching antenna characterized in that it is configured to be selected. In a radio base station using the directivity switching antenna according to claim 1,
The antenna directivity switching control unit, when in the unicast mode, selects from among the antenna directivity that can be selected for each of the plurality of directivity switching antennas, reception power or signal power versus interference with a wireless terminal performing unicast communication. A radio base station using a directivity switching antenna characterized in that each antenna directivity having a maximum power ratio is selected. In a radio base station using the directivity switching antenna according to claim 1,
The antenna directivity switching control unit, in the MU-MIMO mode, selects a signal for each wireless terminal to be a target of MU-MIMO communication from among antenna directivity that can be selected for each of the plurality of directivity switching antennas. A radio base station using a directivity switching antenna characterized in that it is configured to select an antenna directivity that maximizes the sum value or the minimum value of the power to interference power ratio. A radio base station using the directivity switching antenna according to any one of claims 1 to 4.
Signal power adjustment means for adjusting signal power in antenna directivity selected for each of the plurality of directivity switching antennas to a reference value preset for each of the multicast mode, the unicast mode, and the MU-MIMO mode A wireless base station using a directivity switching antenna characterized by comprising: In an antenna directivity control method of a wireless base station including a plurality of directivity switching antennas capable of respectively selecting one of a plurality of antenna directivity, and performing the wireless communication by sharing the same frequency band with one or more wireless terminals,
The wireless signal processing unit is configured to transmit the same wireless signal to a plurality of the wireless terminals, or to perform a unicast mode to transmit and receive one wireless signal or SU-MIMO signal with one wireless terminal. Or performing radio signal transmission / reception processing according to the MU-MIMO mode for transmitting / receiving MU-MIMO signals to / from a plurality of the radio terminals,
The antenna directivity switching control unit performs control to select one antenna directivity for each of the plurality of directivity switching antennas according to the multicast mode, the unicast mode, or the MU-MIMO mode. The antenna directivity control method of the wireless base station characterized by the above. In the antenna directivity control method of a radio base station according to claim 6,
The antenna directivity switching control unit is configured to select, from the antenna directivity that can be selected for each of the plurality of directivity switching antennas in the multicast mode, antenna directivity that can obtain antenna directivity in a wide range as a whole. A method of controlling antenna directivity of a wireless base station characterized by selecting. In the antenna directivity control method of a radio base station according to claim 6,
The antenna directivity switching control unit, when in the unicast mode, selects from among the antenna directivity that can be selected for each of the plurality of directivity switching antennas, reception power or signal power versus interference with a wireless terminal performing unicast communication. A method of controlling antenna directivity of a wireless base station, comprising selecting antenna directivity that maximizes the power ratio. In the antenna directivity control method of a radio base station according to claim 6,
The antenna directivity switching control unit, in the MU-MIMO mode, selects a signal for each wireless terminal to be a target of MU-MIMO communication from among antenna directivity that can be selected for each of the plurality of directivity switching antennas. A method of controlling antenna directivity of a wireless base station, comprising selecting antenna directivity that maximizes the sum value or minimum value of the power-to-interference power ratio. In the antenna directivity control method of a radio base station according to any one of claims 6 to 9,
The signal power in the antenna directivity selected for each of the plurality of directivity switching antennas is adjusted to a reference value preset for each of the multicast mode, the unicast mode, and the MU-MIMO mode. Antenna directivity control method of a wireless base station.

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