JP4574563B2 - Wireless communication system, wireless communication method, base station apparatus, and terminal apparatus - Google Patents

Description

The present invention, such as the outdoor cellular environment, even in an environment where interference is present from neighbor cells, the wireless communication system capable of realizing a high-speed transmission by MIMO technology using space division multiplexing transmission, wireless communication The present invention relates to a method, a base station apparatus, and a terminal apparatus.

  In recent years, studies are being conducted to realize ultrahigh-speed wireless communication of about 100 Mbps to 1 Gbps in a limited frequency band in a mobile phone or a wireless LAN (Local Area Network) system. In order to realize such a wireless communication system, not only the frequency, time, and code are divided for each user, but also the frequency utilization efficiency is improved by the technology using the spatial domain, and the transmission speed is improved. Consideration is being made.

  As a technology for that purpose, MIMO (Multiple-Input Multiple-Output) technology has attracted much attention in recent years. This MIMO technology is such that different independent signals are transmitted on the same channel from a plurality of transmitting antennas on the transmitting station side, and signals are received using the same plurality of antennas on the receiving station side, between each transmitting antenna and the receiving antenna. The transfer function matrix is obtained, the independent signal transmitted from each antenna is estimated on the transmitting station side using this matrix, and the data is reproduced.

  It is known that the theoretical maximum transmission capacity C using the MIMO technique can be theoretically derived by the following equation (see Non-Patent Document 1).

In the above formula (1), ρ is a signal-to-noise power ratio, M is the number of transmitting antenna elements, and _IN is a unit matrix of N × N receiving elements. H is a transfer function matrix representing a propagation channel response between the transmitting antenna and the receiving antenna, and can be described by the following mathematical formula (2).

Here, h _ij is the channel response of the propagation path from the i-th transmitting antenna to the j-th receiving antenna. From equation (1), in MIMO transmission, it is important to first increase the signal-to-noise ratio (SNR) as in the conventional system. Furthermore, in MIMO transmission, it is necessary to lower the correlation between antennas.

  Here, since the SNR is determined based on the distance between the base station apparatus and the terminal apparatus, transmission power, and the prospect between the base station apparatus and the terminal apparatus, basically, the positional relationship between the base station apparatus and the terminal apparatus Is a factor determined by On the other hand, it is known that the correlation greatly depends on the number of elements constituting the antenna to be used, the element directivity, the element spacing, the polarization, the angle spread of the propagation channel, the delay spread, and the like. It is known that this correlation value is relatively low in the indoor environment, but in the outdoor environment, the angle spread of the propagation path is small, so that the correlation between the antennas is very high. Yes.

  FIG. 11 shows a change in the transmission capacity of MIMO transmission when the correlation value is changed with respect to the transfer function matrix H in the wireless communication device of the prior art using two transmitting antenna elements and two receiving antenna elements. The graph shown in FIG. 11 is a change in the transmission capacity of the MIMO transmission when the correlation value is changed with respect to the transfer function matrix H in Equation (1). The horizontal axis represents SNR, and the vertical axis represents transmission capacity. As can be seen from FIG. 11, the transmission capacity of MIMO is significantly reduced due to the extremely high correlation. Therefore, in the MIMO channel, it is very important to lower the correlation between antennas.

  As a technique for performing MIMO transmission while lowering the correlation between antennas, a MIMO configuration using orthogonal polarization shown in FIG. 9 has been proposed (see Non-Patent Document 2). As shown in FIG. 9, on the transmission side, the signal generation unit 1 generates two signals S1 and S2 having different polarizations orthogonal to each other, and the signals S1 and S2 are respectively transmitted to the transmitters 2-1 and 2-2. Thus, transmission is performed from two orthogonal antennas 3-1 and 3-2. On the reception side, signals from the transmission side are received by the receivers 6-1 and 6-2 using the same two orthogonal antennas 5-1 and 5-2, and the signals S 1 and S 2 are received by the decoding processing unit 7. Take out. The polarization of the antenna may be vertical / horizontal polarization, ± 45 degree polarization, right-handed rotation, or left-handed polarization. Although the polarization discrimination degree is slightly deteriorated by the propagation path 4, a cross polarization discrimination degree of about several dB can be ensured in an outdoor environment or the like.

Therefore, when the two polarizations are separated on the receiving side in advance and an interference canceller such as zero forcing (ZF) or MMSE (Minimum Mean Square Error) is used, the correlation between the antennas is high. However, it has been reported that the capacity due to MIMO transmission does not decrease.
IE Telatar, `` Capacity of multiantenna Gaussian channels, '' Euro. Trans. Telecommun., Vol.1, no.6, Nov./Dec. 1999. Paulauj et al., Introduction to Space Time Wireless Communications, Cambridge Publisher, 2003.

  However, the above-described conventional technology has the following problems. An outdoor wireless communication system represented by a cellular system as shown in FIG. 10 is generally a multi-cell environment in which a plurality of base stations have respective service areas. Signals not only from the terminals in the area to be served but also from neighboring cells, that is, areas served by other base stations, arrive as interference. Of course, as shown in FIG. 10, the interference of the same channel from other terminals from within the own cell may be a problem.

  The configuration shown in FIG. 9 is effective in an environment such as an isolated cell in which 1: 1 communication can be realized. However, in the multi-cell environment, there is a problem that the communication quality is greatly deteriorated due to the influence of the interference wave described above.

The present invention has been made to solve the above problems, its object is a wireless communication system that enable high-speed transmission is also a MIMO transmission in a multi-cell environment for use in an outdoor environment, a wireless communication method, a base station apparatus and the terminal To provide an apparatus.

In order to solve the above problems, the present invention includes a plurality of first antennas that transmit and receive signals with predetermined polarizations, and a first signal processing unit that performs space division multiplex transmission through the first antennas. at least one terminal comprising a base station apparatus, and a second signal processing unit for performing space division multiplexing transmission through the plurality of second antenna and the second antenna for transmission and reception of each signal at a predetermined polarizations In the wireless communication system configured by the apparatus, the polarization of the first antenna corresponds to one of two orthogonal polarizations, and the polarization of the second antenna is Each corresponds to one of two orthogonal polarizations, and among the terminal devices, a communication requesting terminal device requesting communication start transmits a request signal to the base station device , and the previous First signal processing unit includes a first received power detector for detecting the reception power of the interference wave for each type of polarization the orthogonal based on signals received through the first antenna, by the request signal The polarization having the smallest received power value among the received power values of the interference wave for each orthogonal polarization type detected by the first received power detection unit is detected and detected. A first selection unit that selects the first antenna that performs transmission using polarized waves as the first antenna used for transmission to the communication requesting terminal device, and the first selection unit that is selected by the first selection unit. A transmission unit that transmits a response signal to the communication start request signal to the communication request terminal device using an antenna, and the second signal processing unit transmits the response signal transmitted from the base station device to the communication request terminal device. Receive through the second antenna A receiving unit, a second received power detector for detecting a received power for each type of the orthogonal polarizations of the receiving portion is the response signal received, said the response signal, the second received power detector As the second antenna used for transmission, the second antenna that transmits with the polarization having the maximum power value among the received power values of the response signal for each type of the orthogonal polarization detected by a wireless communication system characterized by comprising a second selector which selects.

The present invention provides a base station apparatus including a plurality of first antennas each transmitting and receiving a signal with a predetermined polarization and a first signal processing unit performing space division multiplex transmission through the first antenna , At least one terminal device comprising: a plurality of second antennas that transmit and receive signals with the same polarization; and a second signal processing unit that performs space division multiplex transmission through the second antennas
In the wireless communication system constituted by the first antenna, the polarization of the first antenna corresponds to one of two orthogonal polarizations, and the polarization of the second antenna is One of the two orthogonal polarizations corresponds to one of the terminal devices, and the communication requesting terminal device that requests the start of communication transmits a request signal to the base station device. Yes,
The first signal processing unit includes a first reception power detection unit that detects reception power of an interference wave for each of the orthogonal polarization types based on a signal received through the first antenna; and the request signal To calculate the ratio of the reciprocal of the ratio of the received power values of the interference waves for each orthogonal polarization type detected by the first received power detection unit, and transmit the antenna for each polarization type to be transmitted. A first selection unit that selects the first antenna so that the ratio of the number becomes the calculated rate; and the communication request terminal apparatus using the first antenna selected by the first selection unit. A transmission unit that transmits a response signal to the communication start request signal , and the second signal processing unit receives the response signal transmitted from the base station device through the second antenna; Before the receiver receives A second received power detector for detecting a received power for each type of polarization which the orthogonal of the response signal, the by responsive signal, the second receiving power detection unit for each type of polarization of the orthogonal detected A second selection unit that calculates the ratio of the received power values of the response signals and selects the second antenna so that the ratio of the number of antennas for each type of polarization to be transmitted becomes the calculated ratio A wireless communication system.

The present invention is the above-described invention, wherein the base station apparatus is provided between the first selection unit and the transmission unit, and the first antenna selected by the first selection unit When transmitting the response signal to the transmission unit, a transmission beam forming unit is provided that causes the transmission unit to transmit the response signal so as to have directivity in the direction of the communication requesting terminal device.

  In the present invention described above, the base station apparatus may be provided between the first selection unit and the transmission unit, and the first antenna selected by the first selection unit. When transmitting a transmission signal, the received power value detected by the first received power detector and the type of polarization of the signal transmitted from the first antenna selected by the first selector And a transmission power control unit that causes the transmission unit to transmit a transmission signal with transmission power corresponding to the ratio of each.

The present invention includes a plurality of first antennas each transmitting and receiving a signal with a predetermined polarization, and a base station apparatus that performs space division multiplex transmission through the first antenna, and transmitting and receiving a signal with each predetermined polarization A wireless communication method in a wireless communication system including a plurality of second antennas that perform at least one terminal device that performs space division multiplex transmission through the second antennas, Each of the waves corresponds to one of the two orthogonal polarizations, and each of the polarizations of the second antenna corresponds to one of the two orthogonal polarizations , and the inside of the terminal device, in the communication request terminal device requesting communication start, sending a request signal to said base station apparatus, by the base station apparatus, wherein the request from the communication request terminal signal Receiving, said detecting a reception power of the interference wave for each type of polarization to the orthogonal based on the first received signal through the antenna, the interference of each type of the detected polarization to the orthogonal The first antenna that detects the polarized wave having the smallest received power value among the received power values of the waves and performs transmission using the detected polarized wave is used for transmission to the communication requesting terminal device. selecting a first antenna at a selected first antenna using comprises the steps of transmitting a response signal to the request signal of start of communication to the communication request terminal the communication request terminal apparatus, wherein receiving the response signal transmitted from the base station apparatus via the second antenna, detecting the received power for each type of polarization to the orthogonal of said received response signal That step a, the second antenna the power value among the reception power values of the detected said response signal for each polarization type to be the orthogonal transmit at the maximum of the polarization, the second to be used for transmission And selecting as an antenna for the wireless communication method.

The present invention includes a plurality of first antennas each transmitting and receiving a signal with a predetermined polarization, and a base station apparatus that performs space division multiplex transmission through the first antenna, and transmitting and receiving a signal with each predetermined polarization A wireless communication method in a wireless communication system including a plurality of second antennas that perform at least one terminal device that performs space division multiplex transmission through the second antennas, Each of the waves corresponds to one of the two orthogonal polarizations, and each of the polarizations of the second antenna corresponds to one of the two orthogonal polarizations , and the inside of the terminal device, in the communication request terminal device requesting communication start, sending a request signal to said base station apparatus, by the base station apparatus, wherein the request from the communication request terminal signal Receiving, said detecting a reception power of the interference wave for each type of polarization to the orthogonal based on the first received signal through the antenna, the interference of each type of the detected polarization to the orthogonal Calculating the ratio of the reciprocal of the ratio of the received wave power values, and selecting the first antenna such that the ratio of the number of antennas for each type of polarization to be transmitted is the calculated ratio; and at the first antenna using comprises the steps of transmitting a response signal to the request signal of start of communication to the communication request terminal the communication request terminal apparatus, the response signal transmitted from the base station apparatus receiving through the second antenna, and detecting a received power for each type of polarization to the orthogonal of the received the response signal, the orthogonal to the detected The ratio of the received power value of the response signal for each polarization type is calculated, and the second antenna is selected so that the ratio of the number of antennas for each polarization type to be transmitted is the calculated ratio. A wireless communication method comprising the steps of:

In the present invention described above, when the base station apparatus causes the transmitting unit to transmit the response signal using the selected first antenna, the communication station is directed toward the communication request terminal apparatus. The method further includes the step of transmitting the response signal so as to have the characteristics.

  According to the present invention, in the above-described invention, when the transmission signal is transmitted by the selected first antenna in the base station apparatus, the detected received power value and the selected first antenna The method further includes a step of transmitting a transmission signal with a transmission power corresponding to a ratio of the signal transmitted from each polarization type.

The present invention, each comprising a signal processing unit for performing space division multiplexing transmission via a plurality of antennas and the antenna for transmission and reception of signals at a predetermined polarization, performing space division multiplexing transmission and at least one terminal device A base station apparatus in a radio communication system, wherein each antenna has a polarization corresponding to one of two orthogonal polarizations, and requests a communication start in the terminal apparatus communication request terminal apparatus is to transmit a request signal to said base station apparatus, the signal processing unit, the interference wave for each type of polarization the orthogonal based on a signal received through the antenna a reception power detection section that detects a reception power value of the received power is the minimum of the polarization in the received power value of the interference wave for each of the reception polarization power detection unit for the said orthogonal detection type Detect waves, A selector for selecting the antenna that performs transmission at the polarization that issued as the antenna used for transmission to the communication request terminal apparatus, a communication to the communication request terminal apparatus using the antenna in which the selection selecting section has selected A base station apparatus comprising: a transmission unit that transmits a response signal to a start request signal .

The present invention, each comprising a signal processing unit for performing space division multiplexing transmission via a plurality of antennas and the antenna for transmission and reception of signals at a predetermined polarization, performing space division multiplexing transmission and at least one terminal device A base station apparatus in a radio communication system, wherein each antenna has a polarization corresponding to one of two orthogonal polarizations, and requests a communication start in the terminal apparatus communication request terminal apparatus is to transmit a request signal to said base station apparatus, the signal processing unit, the interference wave for each type of polarization the orthogonal based on a signal received through the antenna calculating a reception power detection section for detecting a received power, by the request signal, the ratio of the reciprocal of the ratio of the values of the received power of the interference wave of each type of polarization the received power detecting unit for the said orthogonal detection And send A selection unit antenna number ratio of each type of the polarized waves to select the antenna such that the ratio mentioned above is calculated, the communication to the communication request terminal apparatus using the antenna of the selection selecting section has selected A base station apparatus comprising: a transmission unit that transmits a response signal to a start request signal .

The present invention provides a plurality of first antennas that transmit and receive signals in any one of two orthogonal polarizations, and first signal processing that performs space division multiplex transmission through the first antennas. A first received power detection unit that detects received power of an interference wave for each orthogonal polarization type based on a signal received through the first antenna, and the first received power detection Detecting the polarization having the smallest value of the received power among the values of the received power of the interference wave for each type of the orthogonal polarization detected by the unit, and performing transmission using the detected polarization. A first selection unit that selects one antenna as the first antenna to be used for transmission to the terminal device, and communication with the terminal device is started using the first antenna selected by the first selection unit. A first signal for transmitting a response signal to the request signal And the base station apparatus and a transmission portion, at least one terminal device in a wireless communication system for performing space division multiplexing transmission, the a terminal device, each of which transmission and reception of signals at a predetermined polarization second A second signal processing unit that performs space division multiplex transmission through the antenna and the second antenna, and each of the polarizations of the second antenna corresponds to one of two orthogonal polarizations It is intended, as the terminal device transmits the request signal to the base station apparatus when requesting communication start, also for receiving the response signal to the request signal transmitted from the base station apparatus , and the second signal processing unit, the quadrature of the receiver and the response signal received by the receiver for receiving the response signal transmitted from the base station apparatus via the second antenna That a second received power detecting section for detecting a received power for each type of polarization, by the response signal, the second received power the response signal for each polarization type detection unit to the orthogonal detected the second antenna, wherein the power value in the received power value is transmitted at the maximum of the polarization, characterized by comprising a second selector for selecting as said second antenna used for transmission.

The present invention provides a plurality of first antennas that transmit and receive signals in any one of two orthogonal polarizations, and first signal processing that performs space division multiplex transmission through the first antennas. A first received power detection unit that detects received power of an interference wave for each orthogonal polarization type based on a signal received through the first antenna, and the first received power detection The ratio of the reciprocal of the ratio of the received power values of the interference waves for each orthogonal polarization type detected by the unit is calculated, and the ratio of the first number of antennas for each polarization type to be transmitted is calculated. A response signal for a communication start request signal to the terminal device using the first selection unit that selects the first antenna so that the ratio is equal to the first antenna, and the first antenna selected by the first selection unit. and a first transmission unit that transmits And Chikyoku device, in a wireless communication system in which at least one terminal device performs space division multiplex transmission, the terminal an apparatus, each of a plurality of transmission and reception of signals at a predetermined polarization second antenna and the second A second signal processing unit that performs space division multiplex transmission through the antenna, and the polarization of the second antenna corresponds to one of two orthogonal polarizations, terminal device transmits the request signal to the base station apparatus when requesting communication start, also is intended to receive the response signal to the request signal transmitted from the base station apparatus, said first second signal processing unit, wherein a receiving unit for the response signal received through the second antenna, each of the polarization type for the orthogonal of the response signal received by the receiver is transmitted from said base station apparatus A second received power detector for detecting the received power, by the response signal, the ratio of the values of the received power of the second of the response signal for each type of polarization received power detection unit for the orthogonal detected calculated, wherein the second percentage of the number of antennas for each type of the polarization and a second selector for selecting the second antenna so that the ratio described above is calculated to be transmitted.

  The present invention provides the second antenna for transmitting the polarized wave having the maximum power value among the received power values for each type of the detected polarization in the terminal device according to the invention described above. Is further selected as the second antenna used for transmission.

  According to the present invention, in the above-described invention, the terminal device calculates a ratio of the received power values for each detected polarization type, and a ratio for each transmitted polarization type is calculated. The method further includes the step of selecting the second antenna so as to achieve the above ratio.

  The present invention provides a base station apparatus including a plurality of first antennas each transmitting and receiving a signal with a predetermined polarization and a first signal processing unit performing space division multiplex transmission through the first antenna, Wireless communication system comprising at least one terminal device comprising a plurality of second antennas that transmit and receive signals with the same polarization and a second signal processing unit that performs space division multiplex transmission through the second antennas A first received power detector that detects received power for each type of polarization based on a signal received through the first antenna; Based on the value of received power for each type of polarization detected by the first received power detector, the terminal is selected from the plurality of first antennas so as to reduce interference between the polarized waves. apparatus The first selection unit that selects the first antenna to be used for transmission to the communication requesting terminal device that requests the start of communication, and the first antenna selected by the first selection unit. A base station apparatus comprising: a transmission unit that transmits a transmission signal as a response to a communication start request to a requesting terminal apparatus.

  The present invention provides a base station apparatus including a plurality of first antennas each transmitting and receiving a signal with a predetermined polarization and a first signal processing unit performing space division multiplex transmission through the first antenna, Wireless communication system comprising at least one terminal device comprising a plurality of second antennas that transmit and receive signals with the same polarization and a second signal processing unit that performs space division multiplex transmission through the second antennas The second signal processing unit includes: a receiving unit that receives the transmission signal transmitted from the base station device through the second antenna; and the transmission signal received by the receiving unit. Based on the second received power detector that detects received power for each polarization type, and the received power value for each polarization type detected by the second received power detector. wave A terminal device, characterized in that it comprises from among the plurality of second antenna so as to reduce a second selector for selecting the second antenna to be used in the transmission interference with.

  According to the present invention, a wireless communication system includes a plurality of first antennas that transmit and receive signals with predetermined polarizations, and a first signal processing unit that performs space division multiplex transmission through the first antennas. At least one terminal device comprising a base station device, a plurality of second antennas each transmitting and receiving a signal with a predetermined polarization, and a second signal processing unit performing space division multiplex transmission through the second antenna The first signal processing unit detects the received power for each polarization type based on the signal received through the first antenna, and sets the received power value for each detected polarization type. Based on the first antenna to be used for transmission to the communication requesting terminal device requesting the start of communication in the terminal device from among the plurality of first antennas so as to reduce interference between the polarizations, Selected Transmitting a transmission signal as a response to the request for communication start to the communication request terminal device by using the first antenna. The second signal processing unit receives a transmission signal transmitted from the base station apparatus through the second antenna, detects reception power for each type of polarization of the received transmission signal, and detects the detected polarization of the polarization. Based on the value of the received power for each type, the second antenna used for transmission is selected from the plurality of second antennas so as to reduce the interference between the polarized waves. This makes it possible to estimate the interference between the polarizations based on the value of the received power for each polarization, and to select the second antenna of the polarization type that reduces the interference to the communication requesting terminal device that requests communication. Can be made. In addition, since the notification of the candidate polarization to the communication requesting terminal device is performed based on the polarization of the communication signal to be transmitted without newly using the control information, the notification can be performed without reducing the throughput. . Also, with the above configuration, high-speed transmission can be realized using MIMO technology using space division multiplexing transmission even in an environment where interference waves from adjacent cells exist, such as an outdoor cellular environment.

  Further, according to the present invention, the radio communication system uses the polarization having the smallest received power value among the received power values for each polarization type detected by the first signal processing unit of the base station apparatus. The first antenna that detects and transmits with the detected polarization is selected as the first antenna used for transmission to the communication requesting terminal device. As a result, the type of polarization notified to the terminal device can be indicated by the number of first antennas to be selected.

  Further, according to the present invention, the radio communication system calculates a ratio of the reciprocal of the ratio of the values of the received power for each polarization type detected by the first signal processing unit of the base station apparatus, and transmits the bias. The first antenna is selected so that the ratio for each wave type is the calculated ratio. As a result, the type of polarization notified to the terminal device can be indicated by the ratio of the polarization of signals transmitted from the plurality of first antennas.

  Further, according to the present invention, when the radio communication system transmits a transmission signal using the first antenna selected by the base station apparatus, the transmission signal has directivity toward the communication requesting terminal apparatus. Is configured to transmit. Thereby, the directivity of the transmission signal to be transmitted to the terminal device can be increased, or the directivity to the interference wave can be adjusted, and the terminal device can be selected with high received power. Information on the polarization of the antenna can be notified.

  Further, according to the present invention, when transmitting a transmission signal with the first antenna selected by the base station apparatus, the wireless communication system transmits the value of the detected received power and the selected first antenna. The transmission signal is transmitted with the transmission power according to the ratio of the polarization of each signal to be transmitted. Thereby, since it can transmit to a terminal device with the transmission power which reflected the ratio of the value of received power in detail, the terminal device side can notify the information of the polarization of the antenna used as the candidate selected with high received power.

  Further, according to the present invention, the wireless communication system uses, for transmission, the second antenna that transmits with the polarization having the maximum power value among the received power values for each polarization type detected by the terminal device. It was set as the structure selected as a 2nd antenna. Thereby, the terminal apparatus detects the polarization used for transmission according to the magnitude of the power value for each polarization of the transmission signal transmitted from the base station apparatus, and sets the second antenna that transmits with the detected polarization. You can choose.

  Further, according to the present invention, the wireless communication system calculates the ratio of the received power values for each polarization type detected by the terminal device, and the ratio for each transmitted polarization type becomes the calculated ratio. In this way, the second antenna is selected. Thereby, the terminal apparatus calculates the ratio for each type of polarization used for transmission according to the ratio of the power value for each polarization of the transmission signal transmitted from the base station apparatus, and for each calculated polarization type The second antenna can be selected to constitute a proportion.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

A. First Embodiment FIG. 1 is a block diagram showing a configuration of a wireless communication system 100 according to a first embodiment of the present invention. The radio communication system 100 includes a base station device 200, a plurality of terminal devices 110-1 to 110-6, and a terminal device 120. In FIG. 1, there is a multi-cell environment in which there are four communication areas (hereinafter also referred to as cells) in which wireless communication services are provided by the base station apparatus, that is, communication areas A, B, C, and D. The communication area A is a service area where a radio communication service is provided by the base station apparatus 200, and for the communication areas B, C, and D, the radio communication service is provided by the base station apparatus arranged in each area. Service area.

  FIG. 1 illustrates a state in which the terminal device 120 is newly connected to the base station device 200 while the terminal device 110-1 and the terminal device 110-2 are already connected. Further, the base station apparatus 200 includes a terminal apparatus 110-3 existing in the communication area C existing outside the communication area A of the base station apparatus 200, a terminal apparatus 110-4 and a terminal apparatus 110- existing in the communication area B. 5, an environment in which an interference wave affecting a surrounding cell has arrived from the communication terminal 110-6 existing in the communication area D. Each of the terminal devices 110-1 to 110-6 can transmit and receive vertically polarized radio signals (V1 and V2 in FIG. 1) and horizontally polarized radio signals (H1 and H2 in FIG. 1). It has both or either of the transmitting and receiving antennas.

  FIG. 2 is a block diagram showing an internal configuration of the base station apparatus 200 according to the first embodiment. In the base station apparatus 200, the vertical polarization antennas 10-1 to 10-3 are antennas that transmit and receive a vertically polarized radio signal, and circulators 15-1 and 15 through the vertical polarization ports 12-1 to 12-3. -3, 15-5. The horizontally polarized antennas 11-1 to 11-3 are antennas that transmit and receive horizontally polarized radio signals, and circulators 15-2, 15-4, and 15-6 through the horizontally polarized ports 13-1 to 13-3. Connected. The circulators 15-1 to 15-6 are switches, for example, and are connected to the transmitters 16-1 to 16-6 and the receivers 17-1 to 17-6 on the one hand and the ports to which the antennas are connected on the other hand, That is, it is connected to the vertical polarization ports 12-1 to 12-3 or the horizontal polarization ports 13-1 to 13-3, and the transmitters 16-1 to 16-6 and the receivers 17-1 to 17-6 are connected. Switch to connect to the port.

  The signal processing unit 20 is connected to the transmitters 16-1 to 16-6 and the receivers 17-1 to 17-6, and controls transmission / reception of radio signals. In the signal processing unit 20, the vertical polarization reception power detection unit 27 is connected to receivers 17-1, 17-3, and 17-5 connected to the vertical polarization antennas 10-1 to 10-3. The power of the received signal of vertical polarization received by the receivers 17-1, 17-3, 17-5 is detected. The horizontal polarization received power detection unit 26 is connected to receivers 17-2, 17-4, and 17-6 connected to the horizontal polarization antennas 11-1 to 11-3, and the receiver 17-2, 17-4 and 17-6 detect the power of the received signal of horizontal polarization received.

  The terminal transmission antenna selection unit 23 determines the amount of interference between the vertical polarization and the horizontal polarization based on the power values of the reception signals detected by the vertical polarization reception power detection unit 27 and the horizontal polarization reception power detection unit 26. taking measurement. Further, the terminal transmission antenna selection unit 23 receives an instruction signal for selecting the transmission signal forming unit 21-1 or the transmission signal forming unit 21-2 having a connection to the antenna used for transmission based on the measured interference amount. Output to the switch 22. The memory 24 includes a value of power output from the vertical polarization reception power detection unit 27 that is referred to when the terminal transmission antenna selection unit 23 selects the transmission signal formation unit 21-1 or the transmission signal formation unit 21-2. , The value of the power output from the horizontally polarized wave reception power detection unit 26, and the transmission signal forming unit 21-1 or the transmission signal forming unit 21- selected by the terminal transmission antenna selection unit 23 based on these power values 2 information is stored in association with each other.

  The transmission signal forming unit 21-1 is connected to transmitters 16-1, 16-3, and 16-5 connected to transmission / reception antennas 10-1 to 10-3 that transmit and receive a vertically polarized radio signal, A transmission signal transmitted by the transmitters 16-1, 16-3, and 16-5 is formed. The transmission signal forming unit 21-2 is connected to transmitters 16-2, 16-4, and 16-6 connected to the transmission / reception antennas 11-1 to 11-3 that transmit and receive horizontally polarized radio signals, A transmission signal transmitted by the transmitters 16-2, 16-4, and 16-6 is formed. Based on the instruction signal from the terminal device antenna selection unit 23, the switch 22 forms a transmission signal in one of the transmission signal forming units 21-1 and 21-2, and the transmitter 16-1 connected to each of them. ~ 16-6.

 In the configuration of the base station apparatus 200 shown in FIG. 2, radio signals are transmitted from the vertically polarized antennas 10-1 to 10-3 or the horizontally polarized antennas 11-1 to 11-3. However, the present invention is not limited to this, and two orthogonal polarizations may be used, and ± 45 degree polarization or circular polarization (right transition, left transition polarization) may be used. Good. Further, the orthogonally polarized antenna elements may not be the same.

  FIG. 3 is a block diagram showing an internal configuration of terminal apparatus 120 newly connected to base station apparatus 200 in FIG. The terminal device 120 includes a plurality of vertical polarization antennas 60-1 to 60-N, horizontal polarization antennas 61-1 to 61-N, transmission / reception devices 40-1 to 40-N, and transmission / reception devices 50-1 to 50-50. -N and a signal processing unit 30 are provided.

  The vertical polarization antennas 60-1 to 60-N are connected to the transmission / reception devices 40-1 to 40-N, and the horizontal polarization antennas 61-1 to 61-N are connected to the transmission / reception devices 50-1 to 50-N. Has been. The transmission / reception device 40-1 includes a receiver 41-1, a transmitter 42-1, and a circulator 43-1 for switching between the receiver 41-1 and the transmitter 42-1. It is connected to the wave antenna 30-1. Other transmitting / receiving devices 40-2 to 40-N also have the same internal configuration as the transmitting / receiving device 40-1. Also, the transmitting / receiving devices 50-1 to 50-N have the same internal configuration as the transmitting / receiving devices 40-1 to 40-N, and each circulator 53-1 to 53-N includes a horizontal polarization antenna 61-. 1 to 61-N. Further, the transmission / reception devices 40-1 to 40 -N and the transmission / reception devices 50-1 to 50 -N are connected to the signal processing unit 30.

  In the signal processing unit 30, the vertical polarization reception power detection unit 32 is connected to the receivers 41-1 to 41-N of the transmission / reception devices 40-1 to 40-N, and the receivers 41-1 to 41-N. Detects the power of the received radio signal. The horizontally polarized wave reception power detection unit 33 is connected to the receivers 51-1 to 51-N inside the transmission / reception devices 50-1 to 50-N, and is received by the receivers 51-1 to 51-N. Detect signal power. The terminal transmission element selection control unit 34 is an antenna used for transmission based on the reception power detected by the vertical polarization reception power detection unit 32 and the reception power detected by the horizontal polarization reception power detection unit 33, that is, a vertical polarization antenna. An instruction signal for selecting 60-1 to 60-N and horizontal polarization antennas 61-1 to 61-N is output.

  The memory 37 outputs the power value output from the vertical polarization reception power detection unit 32 used when the terminal transmission element selection control unit 34 selects the antenna and the horizontal polarization reception power detection unit 33. The power values and the antennas selected by the terminal transmission element selection control unit 34 based on these power values, that is, the vertical polarization antennas 60-1 to 60-N and the horizontal polarization antennas 61-1 to 61-N Are stored in association with each other.

  The terminal transmission element selection unit 35 is an antenna used for transmission according to an instruction signal input from the terminal transmission element selection control unit 34, that is, vertical polarization antennas 60-1 to 60-N and horizontal polarization antennas 61-1 to 61-61. -Transmitters 42-1 to 42-N and 52-1 to 52-N connected to -N are selected. The transmission signal generation unit 36 generates a signal to be transmitted, and sends the transmission signal to the transmitter selected by the terminal transmission element selection unit 35 from the transmitters 42-1 to 42-N and 52-1 to 52-N. input.

 Next, processing of the base station apparatus 200 and the terminal apparatus 120 will be described with reference to FIGS. 4 and 5. FIG. 4 is a flowchart showing processing of the base station apparatus 200.

 First, a request signal for requesting the start of communication is transmitted from the terminal device 120 to the base station device 200. When the request signal is received by the vertical polarization antennas 10-1 to 10-3 and the horizontal polarization antennas 11-1 to 11-3 of the base station apparatus 200, the vertical polarization reception power detection unit 27 receives the vertical polarization. The power of the signal is detected as power P, and the horizontal polarization received power detection unit 26 detects the power of the received signal with horizontal polarization as power Q. Then, the vertical polarization reception power detection unit 27 and the horizontal polarization reception power detection unit 26 input the detected values of power P and power Q to the terminal transmission antenna selection unit 23 (step Sa1).

 Published in Shigeru Kozono, Toshinari Tsuruhara and Masayuki Sakamoto, “Base Station Polarization Diversity Reception for Mobile Radio,” IEEE Trans. Veh. Technol., Vol.VT-33, No.4, Nov. 1984. As shown in the figure, the cross polarization discrimination degree of the propagation path in the outdoor environment is secured about several dB. However, on average, if communication is performed using a polarization having a large amount of interference, interference may be increased. Are known. Therefore, the terminal transmission antenna selection unit 23 determines whether power P or the value of power Q is larger based on the input power P and power Q (step Sa2). Then, the terminal transmission antenna selection unit 23 associates the determination result with the values of the power P and the power Q and stores them in the memory 24 (Step Sa3). If larger, in order to reduce interference, an instruction signal to be switched to the horizontal polarization antennas 11-1 to 11-3 side, that is, the transmission signal forming unit 21-2 so that the terminal device 120 preferentially selects the horizontal polarization. Output to the switch 22 (step Sa5).

 On the other hand, when the power Q is smaller than the power P, in order to reduce interference, the vertical polarization antennas 10-1 to 10-3 side, that is, the transmission signal forming unit, causes the terminal device 120 to preferentially select the vertical polarization. An instruction signal for switching to 21-1 is output to the switch 22 (step Sa6). The switch 22 performs switching according to the input instruction signal. The transmission signal forming unit 21-1 or 21-2 selected by the switching uses the vertically polarized antennas 30-1 to 30-30 as a signal including the result for the request signal by the transmitters 16-1 to 16-6 connected thereto. -N or horizontally polarized antennas 31-1 to 31-N (step Sa7).

  Note that the information stored in the memory 24 is obtained from the past information by the terminal transmitting antenna selection unit 23 referring to the memory 24 when, for example, a failure such as inability to receive a radio signal from the terminal device occurs. It is used when selecting either the transmission signal forming unit 21-1 or the transmission signal forming unit 21-2. That is, when referring to the memory 24, the information on the polarization to be used determined in the past is used as it is.

  In the above processing, the vertical polarization reception power detection unit 27 and the horizontal polarization reception power detection unit 26 detect the power when the request signal is received. For example, the measurement is performed at regular intervals. In this case, the power value measured first before receiving the request signal may be output as the detected value.

FIG. 5 is a flowchart showing processing of the terminal device 120 . FIG. 5 shows a flow when the terminal apparatus 120 operates after the processing by the base station apparatus 200 described in FIG.

 First, the terminal device 120 transmits a signal including a result for the request signal from the base device 200. This signal is transmitted with a polarization indicating that the terminal device 120 is preferentially selected when used in transmission. When the terminal device 120 receives signals from the base station device 200 using the vertical polarization antennas 60-1 to 60-N and the horizontal polarization antennas 61-1 to 61-N, the vertical polarization reception power detection unit 32 The received power of vertical polarization is detected as power R. Further, the horizontal polarization received power detection unit 33 detects the received power of horizontal polarization as the power S. Then, the vertical polarization reception power detection unit 32 and the horizontal polarization reception power detection unit 33 input the detected values of power P and power Q to the terminal transmission element selection control unit 34 (step Sb1).

 The terminal transmission element selection control unit 34 determines whether power R or the value of power S is larger based on the input power R and power S (step Sb2). The terminal transmission element selection control unit 34 associates the determination result with the values of the power R and the power S and stores them in the memory 37 (step Sb3). An instruction signal for selecting the wave antennas 60-1 to 60-N is input to the terminal transmission element selection unit 35 (step Sb5). On the other hand, when the power S is smaller than the power R, an instruction signal for selecting the horizontally polarized antennas 61-1 to 61-N is input to the terminal transmission element selection unit 35 (step Sb6). The terminal transmission element selection unit 35 transmits the transmitters 42-1, 42-3,... Connected to the vertical polarization antennas 60-1 to 60-N or the horizontal polarization antenna 61-1, according to the input instruction signal. Are connected to the transmission signal generator 36 by selecting the transmitters 42-2, 42-4,. The transmission signal generation unit 36 generates a transmission signal including data, and passes through the terminal transmission element selection unit 35 to the selected transmitter to the vertical polarization antennas 60-1 to 60-N or the horizontal polarization antenna 61-1. The transmission signal is transmitted from ˜61-N (step Sb7).

 As a result of the above processing, the terminal device 120 can select the polarized wave with the higher power among the received signals, so the base station device 200 transmits a response including the result for the request signal according to the polarization to be selected. By doing so, it is possible to notify the information of the polarization to be preferentially selected. As a result, when the base station apparatus 200 receives a signal while reducing interference with other terminal apparatuses, the amount of interference with the other terminal apparatuses can be reduced. The burden such as signal separation can be greatly reduced, and efficient MIMO transmission can be realized.

 Further, if the configuration is such that a special control signal for causing the terminal device 120 to select a transmission antenna is transmitted, the throughput is greatly reduced. On the other hand, in the above configuration, since it is possible to notify the polarization information transmitted from the base station apparatus 200 to the terminal apparatus 120, it is possible to communicate without reducing the throughput.

 Here, a specific example of processing of the base station apparatus 200 and the terminal apparatus 120 will be described. For example, in the case of FIG. 1, in the terminal devices 110-1 to 110-6 excluding the newly connected terminal device 120, there are four vertical polarizations (V), whereas there are horizontal polarizations (V). H) Since there are six, the amount of interference of horizontally polarized radio signals is increased. In this state, the terminal transmission antenna selection unit 23 of the base station apparatus 200 selects the vertically polarized antennas 60-1 to 60-N as transmission antennas in order to reduce the influence of interference by the newly connected terminal apparatus 120. Information to be transmitted may be transmitted to the terminal device 120. Therefore, base station apparatus 200 transmits, as a communication signal, to terminal apparatus 120 using only the antenna with the polarization determined to have low interference or the antenna with the most polarization.

  The newly connected terminal device 120 receives both components of the vertically polarized antennas 60-1 to 60-N and the horizontally polarized antennas 61-1 to 61-N as shown in FIG. Since only the signal of the vertical polarization component or the signal having a high ratio of the vertical polarization component is transmitted from the base station apparatus 200, even if the polarization characteristic greatly varies in the path of the propagation path, the terminal apparatus 120 receives a large amount of vertical polarization components. The terminal device 120 detects that the polarization designated by the base station device 200 is a vertical polarization from the polarization ratio of the received signal. Strictly speaking, since the ratio of the vertical polarization and the horizontal polarization is an integer ratio when the number of antennas is distributed, the actual ratio is replaced with the integer ratio. A signal transmitted from base station apparatus 200 is also used as a communication signal.

 As a result, the base station apparatus 200 can notify the terminal apparatus 120 of polarization information with a small influence of interference that the terminal apparatus 120 wants to preferentially select. The amount of interference can be reduced as much as possible. Further, since the terminal device 120 can select an antenna regardless of new control information or the like, it is possible to perform MIMO transmission without reducing the throughput.

  In the configuration of the base station apparatus 200 of FIG. 2 described above, the transmission signal forming unit 21-1 includes only the vertically polarized antennas 10-1 to 10-3 through the transmitters 16-1, 16-3, and 16-5. The transmission signal forming unit 21-2 is connected only to the horizontally polarized antennas 11-1 to 11-3 through the transmitters 16-2, 16-4, and 16-6. However, since it is only necessary to reduce the influence of the signal transmitted by the newly connected terminal device 120 on the overall interference, it is not necessary to use polarization on only one side. For example, the terminal is a reciprocal of the power ratio. There are methods such as selecting an antenna for transmission to the device 120.

 Also, the terminal device 120 does not need to use polarized waves on only one side, and similarly to the base station device 200, the ratio of the number of transmission antennas may be determined according to the reception power ratio between polarized waves. . Specifically, there is a method such as selecting an antenna for transmission at a power ratio.

B. Second Embodiment FIG. 6 is a block diagram showing an internal configuration of a base station apparatus 200a according to a second embodiment of the present invention. In the base station apparatus 200a of the second embodiment, the transmission beam forming units 25-1 and 25-2 include a transmission signal forming unit 21a-1, a transmission signal forming unit 21a-2, and transmitters 16-1 to 16-6. Are different from the base station apparatus 200 of the first embodiment in that they are connected to each other.

  In the base station apparatus 200a, signals are not transmitted simply by the transmitters 16-1 to 16-6 selected by the switch 22, but the antennas on the terminal apparatus 120 side are transmitted by the transmission beam forming units 25-1 and 25-2. The signal is transmitted using the antenna polarization selected in the direction. On the base station apparatus 200a side, basic information for estimating the reception level and phase information of the signal from the terminal apparatus 120, the position of the terminal apparatus 120, and the like is acquired in advance. Then, based on the acquired information, a rough direction on the terminal device 120 side is estimated. In the configuration of FIG. 6, unlike the configuration of FIG. 2, the transmission beam forming units 25-1 and 25-2 form directivity toward the terminal device 120, or directivity is not suitable for interference waves. By performing such adjustment, there is an advantage that the terminal device 120 side can be notified of the antenna element to be transmitted with higher received power than the configuration of FIG. In addition, since directivity is formed so that the interference wave is not directed to other terminals as much as possible, the influence of interference is less than that of the previous configuration when viewed from other terminal apparatuses.

 As a specific method for forming the transmission beam in the transmission beam forming units 25-1 and 25-2, an eigenvector corresponding to the maximum eigenvalue obtained by eigenvalue decomposition of the correlation matrix of the received signal is used. There are methods to use as weighting.

C. Third Embodiment FIG. 7 is a block diagram showing an internal configuration of a base station apparatus 200b according to a third embodiment of the present invention. In the base station apparatus 200b of the third embodiment, the transmission signal forming unit 21b-1 is connected to the two vertically polarized antennas 10-1 and 10-3 via the transmitters 16-1, 16-2, and 16-5. And a connection to one horizontally polarized antenna 11-1. Further, the transmission signal forming unit 21b-2 is connected to one vertical polarization antenna 10-2 through the transmitters 16-3, 16-4, and 16-6, and two horizontal polarization antennas 11-2. , 11-3. That is, the transmission signal forming units 21b-1 and 21b-2 to be selected perform transmission not only on one of the polarized waves but also on both polarized waves. However, since the connection is made so that either the vertical polarization or the horizontal polarization has a large ratio, the terminal device 120 can be notified of the polarization to be preferentially selected. Moreover, in the base station apparatus 200b of 3rd Embodiment, the terminal transmission antenna selection part 23b does not determine the magnitude | size of the electric power P and the electric power Q, but determines by the ratio of the electric power P and Q. Specifically, an instruction signal for selecting either the transmission signal forming unit 21b-1 or the transmission signal forming unit 21b-2 is input to the switch 22 in accordance with the reciprocal ratio of the power ratio between the power P and the power Q. Will do.

  Note that the terminal device 120 does not need to use polarized waves on only one side, and is an antenna used for transmission based on the ratio of received power in vertical polarization and horizontal polarization, that is, vertical polarization antennas 60-1 to 60-N, Alternatively, the number of horizontally polarized antennas 61-1 to 61-N may be selected. For example, there is a method of selecting an antenna for transmission at a ratio of a reception power of vertical polarization and a reception power of horizontal polarization.

D. Fourth Embodiment FIG. 8 is a block diagram showing an internal configuration of a base station apparatus 200c according to a fourth embodiment of the present invention. A base station apparatus 200c of FIG. 8 is obtained by improving the configuration of the base station apparatus 200b of the third embodiment shown in FIG. In the base station apparatus 200b of FIG. 7, a large number of transmission antenna elements are assigned to the polarized antenna to be transmitted with priority, but the power transmitted from each antenna is equal power.

  In the base station apparatus 200c of FIG. 8, a transmission power control unit 28-1 that controls transmission power for each antenna for the purpose of further dividing the priority of vertical polarization and horizontal polarization to be transmitted, that is, the ratio to be allocated, The configuration differs from the base station apparatus 200c of FIG. For example, when the switch 22 is switched upward in FIG. 8, the ratio of the number of vertically polarized waves and horizontally polarized antennas connected to the transmission power control unit 28-1 is 2: 1. When transmitting as 2: 1, signals are transmitted with equal power from each antenna. This transmission is the same as the configuration of FIG. On the other hand, for example, when the priority is set to 4: 1, an instruction to double the power transmitted from the vertically polarized antennas 10-1 and 10-3 is given as a transmission power control unit 28- 1 is transmitted, a vertically polarized signal and a horizontally polarized signal can be transmitted at a ratio of 4: 1. That is, in FIG. 8, by providing the transmission power control units 28-1 and 28-2, it is possible to finely specify the priority for selecting the antenna to be transmitted by the terminal device 120.

  In the first to fourth embodiments described above, the processing when the terminal device 120 is newly connected is described. However, the present invention is not limited to these embodiments, and the terminal device 120 is in a communication state. Thus, the processing may be performed when requesting improvement of the communication state.

  The first antenna according to the present invention corresponds to the vertically polarized antennas 10-1 to 10-3 and the horizontally polarized antennas 11-1 to 11-3, and the second antenna is a vertically polarized antenna. This corresponds to 60-1 to 60-N and horizontally polarized antennas 61-1 to 61-N. In addition, the predetermined polarization described in the present invention may be two orthogonal polarizations, vertical polarization and horizontal polarization, ± 45 degrees polarization, circular polarization (right transition, left transition polarization). Etc. The first signal processing unit described in the present invention corresponds to the signal processing units 20, 20 a, 20 b, and 20 c, and the second signal processing unit corresponds to the signal processing unit 30. The first received power detector described in the present invention corresponds to the vertical polarization received power detector 27 and the horizontal polarization received power detector 26, and the second received power detector is a vertical polarization receiver. This corresponds to the power detection unit 32 and the horizontal polarization reception power detection unit 33.

  Moreover, the 1st selection part as described in this invention respond | corresponds to the terminal transmission antenna selection part 23, 23a, 23b, 23c, and the switch 22, and a 2nd selection part is the terminal transmission element selection control part 34, terminal transmission. This corresponds to the element selector 35. The transmitter described in the present invention includes transmitters 16-1 to 16-6 and transmission signal forming units 21-1, 21-2, 21a-1, 21a-2, 21b-1, 21b-2, 21c. -1, 21c-2. The receiving unit described in the present invention corresponds to the receivers 41-1 to 41-N and 51-1 to 51-N. The transmission beam forming unit described in the present invention corresponds to the transmission beam forming units 25-1 and 25-2, and the transmission power control unit corresponds to the transmission power control units 28-1 and 28-2.

1 is a schematic block diagram of a wireless communication system according to a first embodiment of the present invention. It is the block diagram which showed the internal structure of the base station apparatus of 1st Embodiment. It is the block diagram which showed the internal structure of the terminal device of 1st Embodiment. It is the flowchart which showed the process of the base station apparatus of 1st Embodiment. It is the flowchart which showed the process of the terminal device of 1st Embodiment. It is the block diagram which showed the internal structure of the base station apparatus of 2nd Embodiment. It is the block diagram which showed the internal structure of the base station apparatus of 3rd Embodiment. It is the block diagram which showed the internal structure of the base station apparatus of 4th Embodiment. It is a basic block diagram of MIMO transmission using orthogonal polarization, which is a prior art. It is a schematic block diagram of the radio | wireless communications system in a prior art. It is the figure which showed the influence of the channel capacity of MIMO by the correlation between antennas in a prior art.

Explanation of symbols

10-1 to 10-3 Vertical polarization antenna 11-1 to 11-3 Horizontal polarization antenna 16-1 to 16-6 Transmitter 17-1 to 17-6 Receiver 20 Signal processing unit 21-1, 21-21 2 Transmission signal forming unit 22 Switch 23 Terminal transmission antenna selection unit 24 Memory 26 Horizontal polarization reception power detection unit 27 Vertical polarization reception power detection unit

Claims (12)

A base station apparatus comprising a plurality of first antennas each transmitting and receiving a signal with a predetermined polarization, and a first signal processing unit performing space division multiplex transmission through the first antenna ;
At least one terminal device comprising a plurality of second antennas each transmitting and receiving a signal with a predetermined polarization and a second signal processing unit performing space division multiplex transmission through the second antennas
In a wireless communication system composed of:
Each of the polarizations of the first antenna corresponds to one of two orthogonal polarizations,
Each of the polarizations of the second antenna corresponds to one of two orthogonal polarizations,
Among the terminal devices, a communication requesting terminal device that requests communication start is to transmit a request signal to the base station device,
The first signal processing unit includes:
A first received power detector that detects received power of an interference wave for each of the orthogonal polarization types based on a signal received through the first antenna;
Based on the request signal, the polarized wave having the smallest received power value is detected among the received power values of the interference wave for each of the orthogonal polarized wave types detected by the first received power detection unit. A first selection unit that selects the first antenna that performs transmission with the detected polarization as the first antenna to be used for transmission to the communication requesting terminal device ;
A transmission unit that transmits a response signal to the communication start request signal to the communication request terminal device using the first antenna selected by the first selection unit;
The second signal processing unit includes:
A receiving unit that receives the response signal transmitted from the base station device through the second antenna;
A second received power detector that detects received power for each orthogonal polarization type of the response signal received by the receiver;
Based on the response signal, the second received power detection unit transmits the second polarized power having the maximum power value among the received power values of the response signal for each orthogonal polarization type detected by the second received power detection unit. And a second selection unit that selects the second antenna as the second antenna used for transmission . A base station apparatus comprising a plurality of first antennas each transmitting and receiving a signal with a predetermined polarization, and a first signal processing unit performing space division multiplex transmission through the first antenna ;
At least one terminal device comprising a plurality of second antennas each transmitting and receiving a signal with a predetermined polarization and a second signal processing unit performing space division multiplex transmission through the second antennas
In a wireless communication system composed of:
Each of the polarizations of the first antenna corresponds to one of two orthogonal polarizations,
Each of the polarizations of the second antenna corresponds to one of two orthogonal polarizations,
Among the terminal devices, a communication requesting terminal device that requests communication start is to transmit a request signal to the base station device,
The first signal processing unit includes:
A first received power detector that detects received power of an interference wave for each of the orthogonal polarization types based on a signal received through the first antenna;
Based on the request signal, the ratio of the reciprocal of the ratio of the received power value of the interference wave for each of the orthogonal polarization types detected by the first received power detection unit is calculated, and the type of the polarization to be transmitted A first selection unit that selects the first antenna so that the ratio of the number of antennas for each becomes the calculated ratio ;
A transmission unit that transmits a response signal to the communication start request signal to the communication request terminal device using the first antenna selected by the first selection unit;
The second signal processing unit includes:
A receiving unit that receives the response signal transmitted from the base station device through the second antenna;
A second received power detector that detects received power for each orthogonal polarization type of the response signal received by the receiver;
The number of antennas for each type of polarization to be transmitted by calculating the ratio of the received power values of the response signal for each of the orthogonal polarization types detected by the second received power detection unit based on the response signal And a second selection unit that selects the second antenna so that the ratio becomes the calculated ratio . The base station device
The communication requesting terminal device is provided between the first selection unit and the transmission unit, and causes the transmission unit to transmit the response signal using the first antenna selected by the first selection unit. claim 1, characterized in that a transmission beam forming unit for transmitting the response signal to the transmitting unit, or a wireless communication system according to claim 2 so as to have directivity in the direction. The base station device
The first received power detection unit is provided between the first selection unit and the transmission unit and transmits a transmission signal using the first antenna selected by the first selection unit. The transmission signal is transmitted to the transmission unit with transmission power corresponding to the value of the detected reception power and the ratio of the signal transmitted from the first antenna selected by the first selection unit for each polarization type. The wireless communication system according to claim 2 , further comprising: a transmission power control unit for transmitting. A base station apparatus comprising a plurality of first antennas each transmitting and receiving a signal with a predetermined polarization, and performing space division multiplex transmission through the first antenna;
A wireless communication method in a wireless communication system comprising a plurality of second antennas each transmitting and receiving a signal with a predetermined polarization, and comprising at least one terminal device that performs space division multiplex transmission through the second antennas. And
Each of the polarizations of the first antenna corresponds to one of two orthogonal polarizations,
Each of the polarizations of the second antenna corresponds to one of two orthogonal polarizations,
Among the terminal devices, in the communication request terminal device that requests the start of communication,
Transmitting a request signal to the base station device;
In the base station device,
Receiving the request signal from the communication requesting terminal;
Detecting received power of an interference wave for each of the orthogonal polarization types based on a signal received through the first antenna;
The first antenna that detects the polarized wave having the smallest received power value among the detected received power values of the interference wave for each of the detected orthogonal polarization types, and performs transmission using the detected polarized wave Selecting as the first antenna to be used for transmission to the communication requesting terminal device ;
Transmitting a response signal to the communication start request signal to the communication request terminal device using the selected first antenna. In the communication request terminal device,
Receiving the response signal transmitted from the base station apparatus through the second antenna;
Detecting received power for each of the orthogonal polarization types of the received response signal;
Among the received power values of the response signal for each detected orthogonal polarization type, the second antenna that transmits the polarized wave having the maximum power value is selected as the second antenna used for transmission. And steps to
A wireless communication method comprising: A base station apparatus comprising a plurality of first antennas each transmitting and receiving a signal with a predetermined polarization, and performing space division multiplex transmission through the first antenna;
A wireless communication method in a wireless communication system comprising a plurality of second antennas each transmitting and receiving a signal with a predetermined polarization, and comprising at least one terminal device that performs space division multiplex transmission through the second antennas. And
Each of the polarizations of the first antenna corresponds to one of two orthogonal polarizations,
Each of the polarizations of the second antenna corresponds to one of two orthogonal polarizations,
Among the terminal devices, in the communication request terminal device that requests the start of communication,
Transmitting a request signal to the base station device;
In the base station device,
Receiving the request signal from the communication requesting terminal;
Detecting received power of an interference wave for each of the orthogonal polarization types based on a signal received through the first antenna;
The ratio of the reciprocal of the ratio of the received power value of the interference wave for each detected orthogonal polarization type is calculated, and the ratio of the number of antennas for each polarization type to be transmitted is the calculated ratio. Selecting the first antenna in
Transmitting a response signal to the communication start request signal to the communication request terminal device using the selected first antenna. In the communication request terminal device,
Receiving the response signal transmitted from the base station apparatus through the second antenna;
Detecting received power for each of the orthogonal polarization types of the received response signal;
The ratio of the received power value of the response signal for each detected orthogonal polarization type is calculated, and the ratio of the number of antennas for each transmitted polarization type becomes the calculated ratio. Selecting an antenna for
A wireless communication method comprising: In the base station device,
The step of transmitting the response signal so as to have directivity in the direction of the communication requesting terminal device when the transmitting unit transmits the response signal using the selected first antenna is further included. The wireless communication method according to claim 5 or 6 . In the base station device,
When transmitting a transmission signal with the selected first antenna, the value of the detected received power and the ratio of the signal transmitted from the selected first antenna for each type of polarization The wireless communication method according to claim 6 , further comprising: transmitting a transmission signal with transmission power. Each comprises a signal processing unit for performing space division multiplexing transmission via a plurality of antennas and the antenna for transmission and reception of signals at a predetermined polarization, in a wireless communication system for performing at least one terminal device and space division multiplexing transmission A base station device,
Each of the antenna polarizations corresponds to one of two orthogonal polarizations,
Among the terminal devices, a communication requesting terminal device that requests communication start is to transmit a request signal to the base station device,
Said signal processing unit,
A reception power detection section that detects a reception power of the interference wave for each type of polarization the orthogonal based on a signal received through the antenna,
Among the received power values of the interference wave for each of the orthogonal polarization types detected by the received power detection unit, the polarized wave having the smallest received power value is detected and transmitted using the detected polarized wave. A selection unit that selects the antenna to be used as the antenna to be used for transmission to the communication requesting terminal device ;
The base station apparatus characterized by comprising a transmitter which transmits the response signal to the request signal of the communication start to the communication request terminal apparatus using the antenna in which the selection selecting section has selected. Each comprises a signal processing unit for performing space division multiplexing transmission via a plurality of antennas and the antenna for transmission and reception of signals at a predetermined polarization, in a wireless communication system for performing at least one terminal device and space division multiplexing transmission A base station device,
Each of the antenna polarizations corresponds to one of two orthogonal polarizations,
Among the terminal devices, a communication requesting terminal device that requests communication start is to transmit a request signal to the base station device,
Said signal processing unit,
A reception power detection section that detects a reception power of the interference wave for each type of polarization the orthogonal based on a signal received through the antenna,
Based on the request signal, the antenna for each polarization type to be transmitted is calculated by calculating the ratio of the reciprocal of the ratio of the received power values of the interference waves for each orthogonal polarization type detected by the reception power detection unit. A selection unit that selects the antenna so that the ratio of the number is the calculated ratio ;
The base station apparatus characterized by comprising a transmitter which transmits the response signal to the request signal of the communication start to the communication request terminal apparatus using the antenna of the selection selecting section has selected. Each includes a plurality of first antennas that transmit and receive signals in one of two orthogonal polarizations, and a first signal processing unit that performs space division multiplex transmission through the first antennas. A first received power detection unit that detects received power of an interference wave for each of the orthogonal polarization types based on a signal received through the first antenna, and the first received power detection unit detects The first antenna that detects the polarization having the minimum value of the received power among the values of the received power of the interference wave for each of the orthogonal polarization types, and performs transmission using the detected polarization. A response to a request signal for starting communication with the terminal device using the first selection unit selected as the first antenna used for transmission to the terminal device, and the first antenna selected by the first selection unit A first transmitter for transmitting a signal; And the base station apparatus comprising, in a wireless communication system in which at least one terminal device performs a space division multiplexing transmission, a said terminal device,
A plurality of second antennas each for transmitting and receiving signals at a predetermined polarization, and a second signal processing unit for performing space division multiplex transmission through the second antennas,
Each of the polarizations of the second antenna corresponds to one of two orthogonal polarizations,
The terminal device transmits the request signal to the base station apparatus when requesting communication start, also is intended to receive the response signal to the request signal transmitted from the base station apparatus,
The second signal processing unit includes:
A receiving unit that receives the response signal transmitted from the base station device through the second antenna;
A second received power detector that detects received power for each orthogonal polarization type of the response signal received by the receiver;
Based on the response signal, the second received power detection unit transmits the second polarized power having the maximum power value among the received power values of the response signal for each orthogonal polarization type detected by the second received power detection unit . And a second selection unit that selects the second antenna as the second antenna used for transmission. Each includes a plurality of first antennas that transmit and receive signals in one of two orthogonal polarizations, and a first signal processing unit that performs space division multiplex transmission through the first antennas. A first received power detection unit that detects received power of an interference wave for each of the orthogonal polarization types based on a signal received through the first antenna, and the first received power detection unit detects The ratio of the reciprocal of the ratio of the received power values of the interference waves for each orthogonal polarization type is calculated, and the ratio of the first number of antennas for each polarization type to be transmitted is the calculated ratio. The first selection unit for selecting the first antenna and the first antenna selected by the first selection unit transmit a response signal for the communication start request signal to the terminal device. the base station apparatus and a first transmission unit , In a wireless communication system at least one terminal device performs a space division multiplexing transmission, a said terminal device,
A plurality of second antennas each for transmitting and receiving signals at a predetermined polarization, and a second signal processing unit for performing space division multiplex transmission through the second antennas,
Each of the polarizations of the second antenna corresponds to one of two orthogonal polarizations,
The terminal device transmits the request signal to the base station apparatus when requesting communication start, also is intended to receive the response signal to the request signal transmitted from the base station apparatus,
The second signal processing unit includes:
A reception section that receives the response signal transmitted from the base station device through the second antenna,
A second received power detector that detects received power for each orthogonal polarization type of the response signal received by the receiver;
Based on the response signal, the ratio of the received power value of the response signal for each orthogonal polarization type detected by the second received power detection unit is calculated, and the second for each polarization type to be transmitted is calculated . And a second selector that selects the second antenna so that the ratio of the number of antennas is equal to the calculated ratio.

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