JP2019134303A - Wireless communication device and wireless communication system - Google Patents

Abstract

To select an antenna with higher reception quality of a signal more efficiently.SOLUTION: A wireless communication device includes: a first communication unit that transmits a first signal obtained by vibrating an electric field of a high frequency signal in a first direction to another wireless communication device; a transmission unit that transmits the high frequency signal to the other wireless communication device via an optical fiber cable; a reception unit that receives a high frequency signal from the other wireless communication device via the optical fiber; and a second communication unit that transmits a second signal obtained by vibrating an electric field of the high frequency signal received by the reception unit in a second direction different in polarization direction from the first direction to the other wireless communication device.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a wireless communication device and a wireless communication system.

  In recent years, techniques for expanding the communicable area covered by a base station have been developed. As a specific method, there is a method using a diversity method.

  In relation to the above-described method, for example, in Patent Document 1 below, a transmission-side terminal equipped with two antennas transmits the same signal from each antenna, and a reception-side terminal receives a signal, etc. A method for obtaining a diversity gain by performing a signal processing is disclosed. Specifically, the terminal on the transmission side transmits a signal delayed by one symbol length or more from the signal transmitted from the first transmission antenna from the second transmission antenna. Then, the terminal on the receiving side can obtain diversity gain by performing equalization signal processing on the received signal synthesized via the fading circuit.

JP-A 63-286027

  However, in the technique of Patent Document 1, it is necessary to prepare a delay circuit for delaying a signal transmitted from the second antenna by one symbol length or more in the transmitting terminal. In addition, it is necessary to prepare an equalizer for performing equalization signal processing on the combined received signal in the receiving terminal. Therefore, the technique of Patent Document 1 has a problem that digital signal processing becomes complicated.

  Accordingly, the present invention has been made in view of the above problems, and an object of the present invention is to provide a new and improved wireless communication capable of more efficiently selecting an antenna having a high signal reception quality. A communication device and a wireless communication system are provided.

  In order to solve the above-described problem, according to an aspect of the present invention, a first communication unit that transmits a first signal obtained by vibrating an electric field of a high-frequency signal in a first direction to another wireless communication device; A transmitter that transmits the high-frequency signal to another wireless communication device via an optical fiber, a receiver that receives a high-frequency signal from the other wireless communication device via the optical fiber, and the receiver that has received the A second communication unit that transmits the electric field of the high-frequency signal to another wireless communication device as a second signal that is oscillated in a second direction in which the polarization direction is different from the first direction. An apparatus is provided.

  The direction of polarization of the first signal and the direction of polarization of the second signal may be orthogonal to each other.

  The first direction may be either a horizontal direction or a vertical direction, and the second direction may be a direction different from the first direction in the horizontal direction or the vertical direction.

  The wireless communication device may include a plurality of the first communication units and a plurality of the second communication units.

  In order to solve the above problem, according to another aspect of the present invention, a first communication unit that receives a first signal that vibrates in a first direction, the first direction and polarization A second communication unit that receives a second signal that vibrates in a second direction that is different in direction, a first acquisition unit that acquires a first value relating to the first signal, and a second signal that relates to the second signal A second acquisition unit that acquires a second value, and the first value and the second value are selected and demodulated based on the first value and the second value; And a control unit that performs decoding.

  The control unit may compare the first value of the first signal with the second value of the second signal and select a signal having a larger value.

  The first acquisition unit may acquire a detection voltage value as a first value, and the second acquisition unit may acquire a detection voltage value as the second value.

  The wireless communication device may include a plurality of the first communication units and a plurality of the second communication units.

  In order to solve the above problem, according to another aspect of the present invention, a first radio communication device that transmits a high-frequency signal that vibrates in a first direction as a first signal to another radio communication device; A second radio communication device that transmits, as a second signal, a high-frequency signal that vibrates in a second direction different from the first direction to the other radio communication device; and 1 signal, receiving the second signal from the second wireless communication device, obtaining the detection voltage value of each of the first signal and the second signal, and based on the detection voltage value, There is provided a wireless communication system including a third wireless communication apparatus that performs demodulation and decoding by selecting either the first signal or the second signal.

  As described above, according to the present invention, it is possible to more efficiently select an antenna having a high signal reception quality.

It is explanatory drawing which shows the outline | summary of the radio | wireless communications system which concerns on this embodiment. It is explanatory drawing which shows the structural example of the base station which concerns on the same embodiment. It is a block diagram which shows the structural example of the mobile station which concerns on the same embodiment. It is explanatory drawing which shows the example of the detection voltage value which concerns on the same embodiment. FIG. 6 is a sequence diagram showing an operation example of the wireless communication system according to the embodiment. It is a flowchart which shows the example of the signal transmission preparation process which concerns on the same embodiment. It is a flowchart which shows the example of the selection process of the antenna which concerns on the same embodiment. It is the block diagram which showed the hardware structural example of the radio | wireless communication apparatus which concerns on the same embodiment.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the present specification and drawings, components having substantially the same functional configuration are denoted by the same reference numerals, and redundant description is omitted.

  In the present specification and drawings, a plurality of components having substantially the same functional configuration or logical significance may be distinguished by adding different alphabets after the same reference numeral. However, when it is not necessary to particularly distinguish each of a plurality of constituent elements having substantially the same functional configuration or logical significance, only the same reference numeral is given to each of the plurality of constituent elements.

<< 1. Overview of wireless communication system >>
In the present embodiment, a wireless communication device that is a mobile station having a plurality of antennas is connected to a wireless communication device that is a base station having a plurality of antennas based on a plurality of wireless signals having different polarization directions. The present invention relates to a selected wireless communication system. Below, the outline | summary of the radio | wireless communications system which concerns on embodiment of this invention is demonstrated, referring FIG.

  FIG. 1 is an explanatory diagram showing an overview of a wireless communication system according to an embodiment of the present invention. As shown in FIG. 1, the wireless communication system according to the present embodiment includes two base stations 10A, a base station 10B, and a mobile station 20. The two base stations are connected by an optical fiber 30A and an optical fiber 30B.

  In the wireless communication system of the present embodiment, the base station 10 generates a packet and transmits the packet using a wireless signal. At this time, two radio signals having different electric field vibration directions are transmitted from each of the two base stations 10. For example, the first base station 10A transmits the generated packet with a radio signal that vibrates in the horizontal direction. The second base station 10B transmits the packet generated by the base station 10A using a radio signal that vibrates in the vertical direction. Note that the base station 10A and the base station 10B share a packet via the optical fiber 30A and the optical fiber 30B.

  The mobile station 20 performs signal processing on the radio signal received from the base station 10. The mobile station 20 receives a radio signal having a different electric field oscillation direction from each of the base station 10A and the base station 10B, and compares the two radio signals to select an antenna that has received a radio signal with higher reception quality. To do. Then, the mobile station 20 performs signal processing on the radio signal received by the selected antenna.

  Note that the mobile station 20 in the present embodiment is located in an area where the communication area 40A covered by the base station 10A and the communication area 40B covered by the base station 10B overlap. The communication area is a boundary between the communication area 40A and the communication area 40B, and the reception power of the radio signal in the mobile station 20 decreases, so that the quality of the radio communication is likely to deteriorate. In the following, a phenomenon called fading occurs in a propagation path through which a signal transmitted from the base station 10 is received by the mobile station 20. Fading is a radio communication device that moves like a mobile station 20, and the path of electromagnetic waves between transmission and reception changes due to changes in the surrounding environment such as movement of the radio communication device and movement of peripheral objects. This is a phenomenon in which the signal reception level fluctuates dynamically.

  The overview of the wireless communication system according to the embodiment of the present invention has been described above with reference to FIG. Then, the structural example of the radio | wireless communications system which concerns on embodiment of this invention is demonstrated.

<< 2. Configuration example of wireless communication system >>
Below, the structural example of the radio | wireless communications system which concerns on this embodiment is demonstrated, referring FIGS. As described above, the wireless communication system of this embodiment includes the base station 10, the mobile station 20, and the optical fiber 30. In the present embodiment, both the base station 10 that transmits a radio signal and the mobile station 20 that receives the radio signal are radio communication apparatuses.

<2-1. Example of functional configuration of base station>
Hereinafter, the function and configuration example of the base station 10 will be described with reference to FIG. FIG. 2 is a block diagram illustrating a configuration example of the base station 10 which is one of the wireless communication apparatuses according to the embodiment of the present invention. As shown in FIG. 2, the base station 10 according to this embodiment includes a horizontal polarization antenna 110, a vertical polarization antenna 120, a radio signal processing device 130, a distributor 140, an optical transmitter 150, and an optical receiver 160. .

<2-1-1. Example of base station functions>
The base station 10 is a wireless communication device that communicates with the mobile station 20. In the wireless communication system shown in FIG. 1, two base stations 10 transmit and receive packets with the mobile station 20. Each of the two base stations 10 includes a horizontal polarization antenna 110 (first communication unit) and a vertical polarization antenna 120 (second communication unit) as a plurality of antennas.

  The two base stations 10 have different roles. One base station 10A has a role of generating a packet. The base station 10A has a role of generating a packet and transmitting a radio frequency (RF) signal based on the packet to the mobile station 20. At this time, the base station 10 </ b> A transmits an RF signal from the horizontally polarized antenna 110. Further, the base station 10A transmits an RF signal to the base station 10B via the optical fiber 30A. The horizontal direction is the first direction. The RF signal that vibrates in the horizontal direction is the first signal.

  The other base station 10B has a role as a base station that cooperates with the base station 10A. For example, the base station 10B receives the RF signal from the base station A via the optical fiber 30A. Then, the base station 10B transmits the RF signal to the mobile station 20 in a direction of polarization different from the RF signal transmitted from the base station 10A to the mobile station 20 by horizontal polarization. At this time, the base station 10B transmits an RF signal from the vertically polarized antenna 120. The vertical direction is the second direction. The RF signal that vibrates in the vertical direction is the second signal.

  Note that the polarization direction of the first signal and the polarization direction of the second signal are orthogonal to each other in space. As described above, for example, the electric field of the first signal vibrates in the horizontal direction, and the electric field of the second signal vibrates in the vertical direction, so that the polarization direction of the first signal and the second signal The directions of polarization are orthogonal to each other in space. Even if the amount of envelope fluctuation and the amount of phase rotation of each signal in the fading channel are different because the direction of polarization of the first signal and the direction of polarization of the second signal are orthogonal, the mobile station 20 Thus, since the horizontally polarized RF signal and the vertically polarized RF signal are received orthogonally without interfering with each other, the RF signals can be separated.

  Further, the first direction may be either one of the horizontal direction and the vertical direction. However, when the first direction is the horizontal direction, the second direction is the vertical direction. Further, when the first direction is the vertical direction, the second direction is the horizontal direction. As described above, the first direction and the second direction are different directions.

  Further, the roles of the base station 10A and the base station 10B may be reversed. For example, the base station 10A may have a role as a base station that cooperates with the base station 10B, and the base station 10B may have a role of generating a packet.

  Further, the base station 10 is connected to the mobile station 20 by an arbitrary communication method and performs communication. For example, the base station 10 communicates with the mobile station 20 by being connected to an external network. Note that the communication method of the base station 10 is not particularly limited. For example, the base station 10 is connected to the mobile station 20 by wireless communication.

<2-1-2. Example of base station configuration>
(1) Horizontally polarized antenna 110
The horizontally polarized antenna 110 has a function of receiving a radio signal whose electric field vibrates in the horizontal direction and a function of transmitting a radio signal by vibrating it in the horizontal direction. For example, the horizontally polarized antenna 110 in the present embodiment transmits the RF signal input from the distributor 140 by vibrating it in the horizontal direction. The base station 10 may be configured such that the horizontally polarized antenna 110 receives an RF signal from the optical receiver 160.

(2) Vertically polarized antenna 120
The vertically polarized antenna 120 has a function of receiving a radio signal whose electric field vibrates in the vertical direction and a function of transmitting a radio signal by vibrating it in the vertical direction. For example, the vertically polarized antenna 120 in this embodiment transmits an RF signal input from the optical receiver 160 by vibrating it in the vertical direction. The configuration of the base station 10 may be a configuration in which the vertically polarized antenna 120 receives an RF signal from the distributor 140.

(3) Wireless signal processing device 130
The radio signal processing device 130 has a function of generating a packet. For example, the radio signal processing device 130 generates a packet for the base station 10 to transmit to the mobile station 20. Radio signal processing device 130 then outputs an RF signal based on the generated packet to distributor 140.

(4) Distributor 140
The distributor 140 has a function of distributing signals. For example, the distributor 140 distributes the RF signal input from the wireless signal processing device 130 into two. Then, distributor 140 outputs one of the distributed RF signals to horizontal polarization antenna 110 and the other RF signal to optical transmitter 150. The base station 10 may be configured such that the distributor 140 outputs the RF signal to the vertical polarization antenna 120 instead of the horizontal polarization antenna 110.

(5) Optical transmitter 150
The optical transmitter 150 has a function of converting an input signal into an optical signal and transmitting it to another device. For example, the optical transmitter 150 converts the RF signal input from the distributor 140 into an optical signal. Then, the optical transmitter 150 transmits the optical signal to the optical receiver 160 of another base station 10 via the optical fiber 30A.

(6) Optical receiver 160
The optical receiver 160 has a function of converting the received optical signal. For example, the optical receiver 160 converts an optical signal received from the optical transmitter 150 of another base station 10 into an RF signal. Then, the optical receiver 160 outputs the RF signal to the horizontal polarization antenna 110. The base station 10 may be configured such that the optical receiver 160 outputs the RF signal to the horizontal polarization antenna 110 instead of the vertical polarization antenna 120.

  The function and configuration example of the base station according to the embodiment of the present invention have been described above with reference to FIG. Then, the mobile station which concerns on embodiment of this invention is demonstrated.

<2-2. Example of functional configuration of mobile station>
Hereinafter, functions and configuration examples of the mobile station 20 will be described with reference to FIGS. FIG. 3 is a block diagram illustrating a configuration example of the mobile station 20 which is one of the wireless communication apparatuses according to the embodiment of the present invention. As shown in FIG. 3, the mobile station 20 according to this embodiment includes a horizontal polarization antenna 210, a vertical polarization antenna 220, a distributor 230, a detector 240, and a control unit 250.

<2-1-1. Examples of mobile station functions>
The mobile station 20 is a wireless communication device that communicates with the base station 10. In the wireless communication system shown in FIG. 1, the mobile station 20 transmits and receives packets to and from the two base stations 10. The mobile station 20 includes a horizontal polarization antenna 210 (first communication unit) and a vertical polarization antenna 220 (second communication unit) as a plurality of antennas.

  The horizontally polarized antenna 210 of the mobile station 20 receives an RF signal (first signal) that is transmitted from the base station 10 and vibrates in the horizontal direction. In addition, the vertical polarization antenna 220 of the mobile station 20 receives an RF signal (second signal) that vibrates in the vertical direction in which the polarization direction is different from the RF signal received by the horizontal polarization antenna 210. For example, the horizontal polarization antenna 210 of the mobile station 20 receives the RF signal transmitted in the horizontal polarization from the horizontal polarization antenna 110 of the base station 10A. Further, the vertical polarization antenna 220 of the mobile station 20 receives the RF signal transmitted by the vertical polarization from the vertical polarization antenna 120 of the base station 10A.

  Further, the mobile station 20 has a function of performing antenna selection processing based on the RF signal received from the base station 10. For example, the mobile station 20 includes a detector 240A that acquires a detection voltage value of an RF signal received by horizontal polarization and a detector 240B that acquires a detection voltage value of an RF signal received by vertical polarization. An antenna is selected based on each detected voltage value. To select an antenna means that the mobile station 20 selects either an RF signal received with horizontal polarization or an RF signal received with vertical polarization. Then, the mobile station 20 performs processing such as demodulation and decoding on the selected RF signal.

  The detection voltage value of the RF signal (first signal) received with horizontal polarization is an example of a first value related to the RF signal received with horizontal polarization. The detector 240A that acquires the detected voltage value (first value) is an example of a first acquisition unit that acquires the detected voltage value. The detection voltage value of the RF signal (second signal) received with vertical polarization is an example of the second value related to the RF signal received with vertical polarization. The detector 240B that acquires the detected voltage value (second value) is an example of a second acquisition unit that acquires the detected voltage value.

  Note that the first value acquired by the first acquisition unit and the second value acquired by the second acquisition unit are not limited to the detected voltage values. For example, the first acquisition unit and the second acquisition unit may acquire a cross-correlation value instead of the detection voltage value. Then, the mobile station 20 may perform antenna selection processing based on the cross-correlation value.

<2-2-2. Configuration example of mobile station>
(1) Horizontally polarized antenna 210
The horizontally polarized antenna 210 has a function of receiving a radio signal whose electric field oscillates in the horizontal direction and a function of transmitting an RF signal by vibrating the electric field in the horizontal direction. The horizontally polarized antenna 210 in the present embodiment receives, for example, an RF signal that is transmitted from the base station 10 and vibrates in the horizontal direction. Then, the horizontally polarized antenna 210 outputs the received RF signal to the distributor 230A.

(2) Vertically polarized antenna 220
The vertically polarized antenna 220 has a function of receiving a radio signal whose electric field vibrates in the vertical direction, and a function of transmitting an RF signal by vibrating the electric field of the RF signal in the vertical direction. The vertically polarized antenna 220 in the present embodiment receives, for example, an RF radio signal that is transmitted from the base station 10 and vibrates in the vertical direction. Then, the vertical polarization antenna 220 outputs the received RF signal to the distributor 230B.

(3) Distributor 230
The distributor 230 has a function of distributing signals. The distributor 230 in this embodiment includes two distributors, a distributor 230A and a distributor 230B, and distributes signals that vibrate in different directions in each distributor.

  For example, the distributor 230 </ b> A distributes the RF signal received by the horizontal polarization antenna 210. More specifically, the distributor 230A distributes the RF signal input from the horizontally polarized antenna 210 into two. Then, distributor 230A outputs one of the distributed RF signals to detector 240A, and outputs the other RF signal to control unit 250.

  The distributor 230B distributes the RF signal received by the vertically polarized antenna 220. More specifically, the distributor 230B distributes the RF signal input from the vertically polarized antenna 220 into two. Then, distributor 230B outputs one of the distributed RF signals to detector 240B, and outputs the other RF signal to controller 250.

(4) Detector 240
The detector 240 has a function of calculating a detection voltage of the signal. The detector 240 in the present embodiment includes two detectors, a detector 240A and a detector 240B, and calculates a detection voltage value of a signal that vibrates in different directions in each detector.

For example, the detector 240A calculates the detection voltage value V _h of the RF signal received by the horizontally polarized antenna 210. More specifically, detector 240A calculates the detected voltage value _{V h} of the RF signal inputted from the distributor 230A. Then, the detector 240 </ b> A outputs the calculated detection voltage value V _h to the control unit 250.

Also, detector 240B calculates a detected voltage value _{V v} of the RF signal received by the vertical polarization antenna 220. More specifically, detector 240B calculates a detected voltage value _{V v} of the RF signal inputted from the distributor 230B. The detector 240B outputs the calculated detection voltage value _{V v} to the control unit 250.

(5) Control unit 250
The control unit 250 has a function of controlling signal processing. For example, the control unit 250 performs antenna selection determination based on the detected voltage value received from the detector 240. Then, based on the determination result, the control unit 250 selects the RF signal received by the horizontal polarization antenna 210 or the RF signal received by the vertical polarization antenna 220 that is input from the distributor 230, and for the selected RF signal Then, processing such as demodulation and decoding is performed.

  In order to realize the above-described function, the control unit 250 includes a determination unit 252 and a radio signal processing device 254.

(Determination unit 252)
The determination unit 252 has a function of performing determination for selecting an antenna. For example, the determination unit 252 performs antenna selection determination processing based on a plurality of detected voltage values input from the plurality of detectors 240. More specifically, the determination unit 252 receives the detection voltage value V _h of the RF signal received by the horizontal polarization antenna 210 input from the detector 240A and the vertical polarization antenna 220 input from the detector 240B. It compares the detected voltage value V _v of the RF signal, for selecting the antenna that receives the signal having a larger detection voltage value. After the determination process, the determination unit 252 receives the RF signal corresponding to the selected antenna among the RF signal received by the horizontal polarization antenna 210 and the RF signal received by the vertical polarization antenna 220 input from the distributor 230. The data is output to the wireless signal processing device 254.

  Here, the details of the antenna selection process based on the detected voltage value will be described with reference to FIG. FIG. 4 is an explanatory diagram illustrating an example of a detection voltage value according to the embodiment of the present invention. The graph shown in FIG. 4 shows the change over time of the detected voltage value calculated by the detector 240. Further, the vertical axis of the graph indicates the detection voltage value, and the horizontal axis indicates time.

As described above, the determination unit 252 compares the detection voltage value of each RF signal out of the RF signal received by the horizontal polarization antenna 210 and the RF signal received by the vertical polarization antenna 220, and the detection voltage value is large. The antenna corresponding to the other RF signal is selected. For example, at times T _{1 to} T ₂ , the detection voltage value V _h is larger, so the horizontally polarized antenna 210 is selected. In addition, at time T _{2 to} T ₃ , since the detected voltage value V _v is larger, the vertically polarized antenna 220 is selected. Further, at times T _{3 to} T ₄ , the detection voltage value V _h is larger, so the horizontally polarized antenna 210 is selected. Further, at times T _{4 to} T ₅ , since the detection voltage value V _v is larger, the vertically polarized antenna 220 is selected. At time _T 5 through T _6, because the larger the detected voltage value _{V h,} the horizontal polarization antenna 210 is selected.

  The RF signal received by each of the horizontal polarization antenna 210 and the vertical polarization antenna 220 of the mobile station 20 has a detected voltage value as shown in FIG. 4 because the received signal power of each antenna changes over time due to fading. Also changes over time. Therefore, the mobile station 20 continues to select an RF signal having a large detection voltage value based on the determination result of the determination unit 252 described above, thereby allowing a signal to noise power ratio (SNR: Signal to Noise power) of the received signal due to diversity gain. (Ratio) can be easily improved.

(Radio signal processing device 254)
The wireless signal processing device 254 has a function of processing a signal. For example, the radio signal processing device 254 performs demodulation processing and decoding processing on the RF signal. More specifically, the radio signal processing device 254 demodulates the RF signal received by the horizontal polarization antenna 210 or the RF signal received by the vertical polarization antenna 220 that is input from the determination unit 252. Processing and decoding processing are performed.

  The function and configuration example of the mobile station according to the embodiment of the present invention have been described above with reference to FIGS. Then, the optical fiber which concerns on embodiment of this invention is demonstrated.

<2-3. Functional configuration example of optical fiber>
The optical fiber 30 has a function for sharing a packet signal among a plurality of base stations. For example, the optical fiber 30 connects the base station 10A and the base station 10B to each other, and enables packet transmission / reception between the base station 10A and the base station 10B. More specifically, the base station 10A and the base station 10B are connected to each other by an optical fiber 30A and an optical fiber 30B as shown in FIG. The optical fiber 30A is an optical fiber for transmitting an optical signal from the base station 10A to the base station 10B, and transmits an optical signal obtained by converting the packet generated by the base station 10A to the base station 10B. The optical fiber 30B is an optical fiber for transmitting an optical signal from the base station 10B to the base station 10A, and transmits an optical signal obtained by converting the packet generated by the base station 10B to the base station 10A.

  The configuration example of the optical fiber according to the embodiment of the present invention has been described above.

  The configuration example of the wireless communication system according to the embodiment of the present invention has been described above with reference to FIGS. Subsequently, an operation example of the radio communication system according to the embodiment of the present invention will be described.

<< 3. Example of operation >>
Below, the operation example of the radio | wireless communications system which concerns on embodiment of this invention is demonstrated, referring FIGS. FIG. 5 is a sequence diagram showing an operation example of the wireless communication system according to the embodiment of the present invention.

  As shown in FIG. 5, first, the base station 10A prepares to transmit signals to the base station 10B and the mobile station 20 (step S1000). After completing the signal transmission preparation, the base station 10A transmits an RF signal from the horizontally polarized antenna 110A to the mobile station 20 (step S1004). Further, the base station 10A transmits an optical signal to the base station 10B via the optical fiber 30A (step S1008). The base station 10B that has received the optical signal from the base station 10A converts the optical signal into an RF signal (step S1012). After the conversion process, the base station 10B transmits the RF signal from the vertically polarized antenna 120B to the mobile station 20 (step S1016). Then, the mobile station 20 performs processing for selecting an antenna based on the RF signal received in the horizontal polarization from the base station 10A in step S1004 and the RF signal received in the vertical polarization from the base station 10B in step S1016. This is performed (step S1020).

  Here, the details of the signal transmission preparation process in step S1000 will be described with reference to FIG. FIG. 6 is a flowchart showing an example of signal transmission preparation processing according to the embodiment of the present invention. As shown in FIG. 6, first, the base station 10A generates a radio packet by the radio signal processing device 130A (step S2000). Next, the base station 10A distributes the RF signal based on the radio packet by the distributor 140A (step S2004). Then, the base station 10A outputs one of the distributed RF signals to the horizontally polarized antenna 110A (step S2008), and outputs the other RF signal to the optical transmitter 150A (step S2012).

Details of the antenna selection process in step S1020 will be described with reference to FIG. FIG. 7 is a flowchart showing an example of antenna selection processing according to the embodiment of the present invention. First, the mobile station 20 detects the detection voltage value V _h of the RF signal received by the horizontal polarization antenna 210 received from the base station 10A and the detection voltage of the RF signal received by the vertical polarization antenna 220 received from the base station 20B. to calculate the value _{V v.} Incidentally, the processing in steps S3000, and 3004 calculates the detected voltage value _{V h,} the processing in step S3008, and 3012 calculates the detected voltage value _{V v} is capable of parallel processing.

As the first parallel processing, first, the mobile station 20 distributes the RF signal received by the horizontally polarized antenna 210 received from the base station 10A in step S1004 of FIG. 5 by the distributor 230A (step S3000). Then, the mobile station 20, the detection voltage value _{V h} of the RF signals received at one of the horizontal polarization antenna 210 distributed, calculated by the detector 240A (step S3004).

As the second parallel processing, first, the mobile station 20 distributes the RF signal received by the vertically polarized antenna 220 received from the base station 10B in step S1016 of FIG. 5 by the distributor 230B (step S3008). Then, the mobile station 20, the detection voltage value _{V v} of the RF signal received by one of the vertically polarized antenna 220 that is dispensed is calculated by the detector 240B (step S3012).

After parallel processing completion determination unit 252 of the mobile station 20, the detected voltage value _{V h} to check whether larger than the detected voltage value _{V v} (step S3016). If direction of detection voltage _{V h} is larger (step S3016 / YES), the determination unit 252 selects the horizontally polarized antenna 210 (step S3020). Also, if the direction of detection voltage _{V h} is smaller (step S3016 / NO), the determination unit 252 selects a vertically polarized antenna 220 (step 3024). After selecting the antenna, the determination unit 252 outputs the RF signal received by the selected antenna to the wireless signal processing device 254. Then, the radio signal processing device 254 performs signal processing based on the RF signal (step S3028).

  The operation example of the wireless communication system according to the embodiment of the present invention has been described above with reference to FIGS.

  The embodiment of the present invention has been described above with reference to FIGS. Subsequently, a modification according to the embodiment of the present invention will be described.

<< 4. Modification >>
Hereinafter, some modifications of the embodiment of the present invention will be described. In addition, each modification demonstrated below may be applied to embodiment of this invention independently, and may be applied to embodiment of this invention in combination. Each modification may be applied instead of the configuration described in the embodiment of the present invention, or may be additionally applied to the configuration described in the embodiment of the present invention.

The above embodiment has been described on the assumption that the wireless communication apparatus performs SISO (Single Input and Single Output) transmission. However, as a modification of the present embodiment, the wireless communication apparatus includes a plurality of first communication units and a plurality of second communication units, and superimposes and transmits wireless packets at the same frequency in multiple input and transmission (MIMO). (Multiple Output) transmission may be performed. For example, the base station 10 includes N horizontal polarization antennas and N vertical polarization antennas, thereby transmitting N packets. In addition, the mobile station 20 includes N horizontal polarization antennas and N vertical polarization antennas, so that each antenna receives N packets. The mobile station 20 calculates a statistical value such as an average value or median value of V _h and V _v for the N detected voltage values V _h and N detected voltage values V _v , and An antenna selection determination process is performed based on the comparison of values.

As described above, the mobile station 20, by performing the selection process of the antenna based on a plurality of detected voltage values V _h and V _v, when performing processing for selecting an antenna based on one of the detected voltage value V _h and V _v The antenna can be selected with higher accuracy than the above.

  In the above, the modification which concerns on embodiment of this invention was demonstrated. Subsequently, a hardware configuration of the wireless communication apparatus according to the embodiment of the present invention will be described.

<< 5. Hardware configuration >>
Finally, the hardware configuration of the wireless communication apparatus according to the embodiment of the present invention will be described with reference to FIG. FIG. 8 is a block diagram illustrating an example of a hardware configuration of the wireless communication apparatus according to the embodiment of the present invention. Note that the wireless communication apparatus 900 illustrated in FIG. 8 can realize, for example, the base station 10 or the mobile station 20 illustrated in FIGS. 2 and 3, respectively. The wireless communication processing by the base station 10 or the mobile station 20 according to the embodiment of the present invention is realized by cooperation between software and hardware described below.

  As shown in FIG. 8, the wireless communication apparatus 900 includes a CPU (Central Processing Unit) 901, a ROM (Read Only Memory) 903, and a RAM (Random Access Memory) 905. The wireless communication device 900 includes a storage device 907 and a network interface 909.

  The CPU 901 functions as an arithmetic processing device and a control device, and controls the overall operation in the wireless communication device 900 according to various programs. Further, the CPU 901 may be a microprocessor. The ROM 903 stores programs used by the CPU 901, calculation parameters, and the like. The RAM 905 temporarily stores programs used in the execution of the CPU 901, parameters that change as appropriate during the execution, and the like. These are connected to each other by a host bus including a CPU bus. For example, the CPU 901, the ROM 903, and the RAM 905 can realize the function of the wireless signal processing device 130 described with reference to FIG. Further, the CPU 901, the ROM 903, and the RAM 905 can realize the function of the control unit 250 described with reference to FIG.

  The storage device 907 is a device for storing data. The storage device 907 may include a storage medium, a recording device that records data on the storage medium, a reading device that reads data from the storage medium, a deletion device that deletes data recorded on the storage medium, and the like. The storage device 907 includes, for example, an HDD (Hard Disk Drive) or an SSD (Solid Storage Drive), or a memory having an equivalent function. The storage device 907 drives the storage and stores programs executed by the CPU 901 and various data.

  The network interface 909 is a communication interface configured with, for example, a communication device for connecting to a network. Such communication interfaces include, for example, a short-range wireless communication interface such as Bluetooth (registered trademark) or ZigBee (registered trademark), a wireless LAN (Local Area Network), Wi-Fi (registered trademark), or a portable communication network (LTE). 3G). The network interface 909 may be a wired communication device that performs wired communication. The network interface 909 may realize the functions of the horizontally polarized antenna 110, the vertically polarized antenna 120, the optical transmitter 150, and the optical receiver 160 described with reference to FIG. Further, the network interface 909 can realize the functions of the horizontally polarized antenna 210 and the vertically polarized antenna 220 described with reference to FIG.

  The example of the hardware configuration of the wireless communication apparatus has been described above with reference to FIG.

<< 6. Conclusion >>
As described above, in the radio communication apparatus according to the embodiment of the present invention, the base station 10A transmits the horizontally polarized RF signal to the mobile station 20 by the horizontally polarized antenna (first communication unit). Further, the base station 10A transmits an RF signal from the optical transmitter (transmitter) to the optical receiver (receiver) of the base station 10B via the optical fiber 30A. Then, the base station 10B transmits a vertically polarized RF signal to the mobile station 20 from the vertically polarized antenna (second communication unit).

  As described above, the base station 10 can transmit, to the mobile station 20, RF signals that are different from each other in the electric field oscillation direction and are orthogonal to each other. As a result, the mobile station 20 can select an antenna that receives an RF signal with higher received power based on the two received RF signals. Further, it is not necessary to prepare a delay circuit in the base station 10 and an equalizer in the mobile station 20, and the digital signal processing is not complicated.

  Therefore, it is possible to provide a new and improved radio communication apparatus and radio communication system that can more efficiently select an antenna having a high signal reception quality.

<< 7. Supplement >>
The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings, but the present invention is not limited to such examples. It is obvious that a person having ordinary knowledge in the technical field to which the present invention pertains can come up with various changes or modifications within the scope of the technical idea described in the claims. Of course, it is understood that these also belong to the technical scope of the present invention.

  Note that the steps in the processing of the wireless communication system of the present specification do not necessarily have to be processed in time series in the order described in the flowchart. For example, each step in the processing of the wireless communication system may be processed in an order different from the order described as the flowchart, or may be processed in parallel. Further, additional processing steps may be employed, and some processing steps may be omitted.

DESCRIPTION OF SYMBOLS 10 Base station 20 Mobile station 30 Optical fiber 110 Horizontal polarization antenna 120 Vertical polarization antenna 130 Radio | wireless signal processing apparatus 140 Divider 150 Optical transmitter 160 Optical receiver 210 Horizontal polarization antenna 220 Vertical polarization antenna 230 Divider 240 Detection 250 Control unit 252 Determination unit 254 Radio signal processing device

Claims (9)

A first communication unit that transmits the electric field of the high-frequency signal to another wireless communication device as a first signal that vibrates in a first direction;
A transmitter for transmitting the high-frequency signal to another wireless communication device via an optical fiber;
A receiver that receives a high-frequency signal from the other wireless communication device via the optical fiber;
A second communication unit that transmits the electric field of the high-frequency signal received by the reception unit to another wireless communication device as a second signal that is oscillated in a second direction in which the polarization direction differs from the first direction. When,
A wireless communication device.   The wireless communication apparatus according to claim 1, wherein a polarization direction of the first signal and a polarization direction of the second signal are orthogonal to each other.   The first direction is one of a horizontal direction and a vertical direction, and the second direction is a direction different from the first direction in the horizontal direction or the vertical direction. Wireless communication device.   The wireless communication apparatus according to claim 1, wherein the wireless communication apparatus includes a plurality of the first communication units and a plurality of the second communication units. A first communication unit that receives a first signal that vibrates in a first direction;
A second communication unit that receives a second signal that vibrates in a second direction that is different in polarization direction from the first direction;
A first acquisition unit for acquiring a first value related to the first signal;
A second acquisition unit for acquiring a second value relating to the second signal;
A control unit that performs demodulation and decoding by selecting either the first signal or the second signal based on the first value and the second value;
A wireless communication device.   The wireless communication according to claim 5, wherein the control unit compares the first value of the first signal with the second value of the second signal and selects a signal having a larger value. apparatus.   The radio according to claim 5 or 6, wherein the first acquisition unit acquires a detection voltage value as a first value, and the second acquisition unit acquires a detection voltage value as the second value. Communication device.   The wireless communication device according to claim 5, wherein the wireless communication device includes a plurality of the first communication units and a plurality of the second communication units. A first wireless communication device that transmits a high-frequency signal that vibrates in a first direction as a first signal to another wireless communication device;
A second wireless communication device that transmits a high-frequency signal that vibrates in a second direction different from the first direction to the other wireless communication device as a second signal;
The first signal is received from the first wireless communication device, the second signal is received from the second wireless communication device, and the detection voltage value of each of the first signal and the second signal is obtained. A third wireless communication device that acquires and demodulates and decodes by selecting either the first signal or the second signal based on the detected voltage value;
A wireless communication system.

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