JP6836475B2 - Wireless communication system, wireless communication method and wireless communication device - Google Patents

Description

The present invention relates to wireless communication systems, wireless communication methods and wireless communication devices.

In recent years, research and development and practical application of wireless communication methods in line-of-sight transmission lines using high frequency bands such as quasi-millimeter wave and millimeter wave, such as 5th generation mobile communication systems and millimeter-wave wireless LAN (Local Area Network), have been promoted. ing. In addition, the millimeter wave band is being actively used when constructing a high-speed wireless communication system represented by an indoor wireless LAN.

Among millimeter waves, the 60 GHz band in particular has a large bandwidth of 4% per frequency channel, that is, a frequency bandwidth of about 2 GHz, which can be used without a license. In IEEE802.11ad, which is a wireless LAN system using the 60 GHz band, products that perform high-speed transmission of 4 Gbit / s or more by SISO (Single-Input-and-Single-Output) transmission using one frequency channel are on the market. It has been put on the market, and further speeding up of the transmission speed is desired.

There are several methods for increasing the transmission speed of wireless communication. For example, there are a method of widening the frequency band to be used, a method of increasing the amount of information transmitted by one symbol by using multi-value modulation, and the like. In addition to these, there is a method using MIMO (Multiple-Input-and-Multiple-Output) transmission technology as one of the realization methods for increasing the transmission speed within a certain frequency band.

In high frequency bands such as quasi-millimeter waves and millimeter waves, a method of performing spatial division wireless transmission and parallel wireless transmission using an antenna with high directivity while using a wide band is suitable, and MIMO transmission technology. It is expected that high-speed transmission exceeding 10 Gbit / s can be realized by using the above spatial multiplexing transmission together.

In MIMO transmission technology, different signals are transmitted from a plurality of transmitting antennas at the same time and at the same frequency, and by using a multipath environment between transmitters and receivers, each signal is separated and decoded by signal processing on the receiving side. As a result, the transmission speed can be increased according to the number of transmission / reception antenna elements without widening the frequency band used. MIMO transmission technology is premised on propagating radio waves in an environment rich in multipath. The reason is that when the transmitter / receiver is not in a multipath environment, the transmission paths of the plurality of signals transmitted / received become almost equal, the spatial correlation increases, signal separation becomes difficult, and the channel capacitance decreases.

On the other hand, Non-Patent Document 1 discloses a technique for applying MIMO transmission technology to short-range communication in an environment in which a transmitting antenna and a receiving antenna are close to each other, which is not a multipath environment. According to Non-Patent Document 1, when MIMO transmission is performed in short-range communication, the spatial correlation between antennas is provided even in a non-multipath environment by appropriately giving the element spacing of the antenna array to the distance between transmitters and receivers. It is said that it is possible to achieve a high transmission line capacity. Therefore, it is considered that the technology shown in Non-Patent Document 1 is one of the technologies that makes it possible to carry out spatially divided wireless transmission and parallel wireless transmission in high frequency bands such as quasi-millimeter wave and millimeter wave. Be done.

Japanese Unexamined Patent Publication No. 2014-195238

Naoki Honma, Kentaro Nishimori, Tomohiro Seki, Masato Mizoguchi, "Evaluation of Transmission Capacity in Nearby MIMO Communication", IEICE Tech. Takaaki Shirai, Kentaro Nishimori, Yoshitomo Katsuoka, Hideo Makino, "Parallel transmission by narrow beam formation in LOS-MIMO transmission", Institute of Electronics, Information and Communication Engineers, November 2013, AP2013-106, pp .37-42 Ken Hiraga, Ikko Sakamoto, Maki Arai, Tomohiro Seki, Hideki Toshinaga, Masao Nakagawa, "Study of Parallel Transmission Based on Two-Wave Propagation Model", Institute of Electronics, Information and Communication Engineers, October 2014, A・ P2014-127, pp.105-110

However, MIMO transmission technology requires transmission beamforming, transmission line matrix feedback processing, signal processing for decoding MIMO, and the like. Signal processing in MIMO is usually performed by digital signal processing. Since the amount of calculation is proportional to the square of the number of multiplexes of MIMO and proportional to the bandwidth, the speedup is accompanied by an increase in the amount of calculation. Further, a wireless communication module to which the function of MIMO transmission technology is applied to millimeter-wave band communication such as IEEE802.11ad has not been developed for the market at present.

On the other hand, there is a method of realizing spatial multiplexing transmission by using an existing SISO wireless communication module without using MIMO transmission technology. One of the promising methods is to parallelize the transmission paths of radio waves and secure sufficient isolation between the parallelized transmission paths to transmit multiple RF (Radio Frequency) signals in parallel. There is. For example, by increasing the distance between the antenna elements, it is possible to increase the isolation between the transmission paths composed of the antenna elements facing each other in the front, and in addition to this, by using an antenna element with high directivity. Spatial multiplexing transmission can be realized by SISO transmission technology.

FIG. 13 is a diagram showing an example of the space division transmission wireless communication system 800. In the space division transmission wireless communication system 800, the width of the directional beam is narrowed by using the antenna elements 810-1,810-2,820-1,820-2 having high directivity. Thereby, a simple method of increasing the isolation between the first and second radio links 840,850 is used.

In the space division transmission radio communication system 800, in order to obtain isolation between desired radio links, the distance between the first antenna array 810 and the second antenna array 820, that is, the transmission distance of the radio signal is relative to the distance. It is necessary to sufficiently increase the distance between the antenna elements of the first and second antenna arrays 810 and 820, and further reduce the width of the directional beam sufficiently. Here, the intervals between the antenna elements of the first and second antenna arrays 810 and 820 are the intervals between the antenna elements 810-1 and 810-2 of the first antenna array 810 and the antenna elements 820 of the second antenna array 820. It is an interval of -1,820-2.

For example, as an antenna element with high directivity, there are a horn antenna having a three-dimensional structure and a Yagi-Uda antenna having a large number of directors. However, since the horn antenna has a high manufacturing cost and the Yagi-Uda antenna has a large depth, it is assumed that it is not suitable for practical use in terms of cost and size.

On the other hand, when an antenna element having low directivity is used, the isolation between the respective transmission paths can be increased by making the distance between the antenna elements very long. However, this configuration is not suitable for practical use from the viewpoint of the size of the wireless transmitter / receiver, for example, because the distance between the antenna elements in the antenna array becomes too long as disclosed in Non-Patent Document 2. is assumed.

FIG. 14 is a diagram showing a configuration of a space division transmission wireless communication system 801 which is an example of the system disclosed in Patent Document 1. In the space division transmission wireless communication system 801 the first antenna array 811 which is one antenna array includes two antenna elements 810-1a and 810-2a. The antenna element 810-1a has a configuration in which two antenna elements 810-1a-1,810-1a-2 are connected, and the antenna element 810-2a has two antenna elements 810-2a-1,810-. It has a configuration in which 2a-2 is connected. Each one of the antenna elements 810-1a-2, 810-2a-2 includes phase shifters 850-1,850-2 that give a phase rotation of 180 degrees.

With this configuration, the radio waves radiated from the antenna element 810-1a-1 and the antenna element 810-1a-2 reach the antenna element 820-1 in opposite phases. Therefore, the radio wave radiated from the antenna element 810-1a is canceled by the antenna element 820-1, so that the antenna element 820-1 does not receive the radio wave from the antenna element 810-1a. Similarly, the antenna element 820-2 does not receive radio waves from the antenna element 810-2a.

By setting the interval between the antenna elements 810-1a-1 and 810-1a-2 to an appropriate length, the radio waves radiated by the antenna elements 810-1a-1 and 810-1a-2 are transmitted to the antenna element 820-2. Can be reached under conditions that are in phase, or at least not out of phase. Similarly, by setting the interval between the antenna elements 810-2a-1 and 810-2a-2 to an appropriate length, the radio waves radiated by the antenna elements 810-2a-1 and 810-2a-2 can be transmitted to the antenna element 820. -1 can be reached under conditions that are in phase, or at least not out of phase. As a result, the two first and second radio links 840 and 850 shown in FIG. 14 can be configured.

However, in order to realize this method, one of the two RF input / output signals of the wireless signal processing circuit in the wireless communication module is distributed to the two antenna elements 810-1a-1 and 810-1a-2. , The other system needs to be distributed to the two antenna elements 810-2a-1 and 810-2a-2. However, many millimeter-wave wireless communication modules process communication signals in order to minimize power supply loss between the wireless signal processing circuit and the antenna, and to use an electronically controllable phased antenna array. The LSI (Large Scale Integrated circuit) and the antenna element are integrated. At present, in millimeter-wave wireless communication in which such an integrated wireless communication module must be used, in order to apply the above-mentioned spatial division transmission, it is necessary to newly develop a communication signal processing LSI. Moreover, such new development is not easy.

FIG. 15 is a diagram showing a configuration of a parallel transmission wireless communication system 802, which is an example of the system disclosed in Non-Patent Document 3. In the parallel transmission wireless communication system 802, the first and second antenna arrays 810 and 820 are installed on the ground 880 at the same height to perform parallel wireless transmission. In the parallel transmission wireless communication system 802, the millimeter-wave wireless communication module with an integrated antenna can be applied as it is without any special modification to the parts of the first and second antenna arrays 810 and 820.

In the parallel transmission radio communication system 802, most of the energy reflected by the earth 880 is concentrated in the reflection area 870 located exactly in the middle of the first and second antenna arrays 810,820. Therefore, when wireless communication is performed between the first and second antenna arrays 810 and 820, if there is no suitable ground 880 near the reflection area 870, for example, a reflector such as a metal plate having a sufficient size. There is an inconvenience that the antenna must be manually installed separately from the wireless transmitter / receiver.

In view of the above circumstances, the present invention is the same in the line-of-sight transmission line without widening the antenna element spacing in the antenna array without high-speed signal processing even when there is no ground between the opposing antenna elements. The purpose is to provide a technology capable of spatial multiplexing transmission using a frequency band.

One aspect of the present invention includes a first radio control device connected to a first antenna array including a plurality of antenna elements, and a second radio control device connected to a second antenna array including a plurality of antenna elements. , A wireless communication system including a reflecting member having a reflecting surface that reflects radio waves radiated by the antenna element, wherein the plurality of antenna elements are on an antenna element plane in which their phase centers are the same plane. Positioned and the front surface of the first antenna array and the front surface of the second antenna array are parallel or substantially parallel, and the antenna element plane is the first and second antennas. It is perpendicular to or substantially perpendicular to the front surface of the array, and the reflective member is located outside the quadrilateral region surrounded by the phase center of the antenna element of the first and second antenna arrays. At least one of the antenna elements of the first and second antenna arrays, at a position closer to one of the antenna elements than the midpoint of the first radio control device and the second radio control device. Of the radio radio waves radiated from the antenna element included in a part of the antenna array located at a position where the reflecting member is located at a position where the reflecting surface is perpendicular or substantially perpendicular to the antenna element plane. A direct wave that reaches the antenna element included in the other antenna array at a diagonal position of the quadrilateral region, and a reflected wave that is reflected by the reflecting member of the radio wave and reaches the antenna element. Is a wireless communication system including the plurality of antenna elements and the reflection member so that the antenna elements are synthesized in opposite phases.

One aspect of the present invention is the above-mentioned wireless communication system, in which there are a plurality of the reflecting members, and the reflecting members are located close to each of the plurality of antenna elements included in the antenna array of one of the wireless control devices. Or some of the reflective members are located closer to any of the antenna elements included in the first antenna array, and the reflective members are closer to the first antenna array. The other reflecting member is located at a position close to the antenna element included in the second antenna array, which is adjacent to the antenna element in the quadrilateral region.

One aspect of the present invention is the above-mentioned wireless communication system, in which the reflecting member is located at a position close to a part of the antenna elements included in the antenna array of one of the wireless control devices. An absorbing member that absorbs the radio wave is provided at a position between the antenna elements that blocks the radio wave radiated from the antenna element and does not reach the reflecting member.

One aspect of the present invention is the wireless communication system, which has one reflecting member, regards the antenna element plane as an XY coordinate plane, and is included in the antenna array of the first wireless control device. When a straight line including a line segment between the phase centers of the antenna elements is defined as the Y axis, the value of the Y coordinate of each of the antenna elements included in the antenna array of the second radio control device is the first radio control. Each radio control device is provided with an antenna element so as to be smaller than the value of the Y coordinate of each of the antenna elements included in the antenna array of the device, and the reflecting member is the antenna element having the largest value of the Y coordinate. , Or, it is located at a position closer to the antenna element having the smallest value of the Y coordinate.

One aspect of the present invention is the wireless communication system, wherein the reflecting member is positioned so that the reflecting surface is perpendicular to or substantially perpendicular to the front surface of the first and second antenna arrays. Or, the reflecting surface is tilted so as to face the direction of the antenna array existing at a position facing the front surface of the first and second antenna arrays from a position perpendicular to the front surface.

One aspect of the present invention is the wireless communication system, wherein the reflective surface of the reflective member is radiated from the antenna element of the first wireless control device and reflected by the reflective surface to form the quadrilateral region. It has a size including the first Fresnel zone of the reflected wave reaching the antenna element included in the antenna array of the second radio control device at a diagonal position.

One aspect of the present invention is the above-mentioned wireless communication system, in which the position of the antenna element, the distance between a plurality of the antenna elements included in the antenna array, or the antenna element and the antenna element are approached. The distance to the reflecting member existing at the position, the tilt angle of the reflecting member, or the direction of the beam of the radio wave radiated from the antenna element is variable.

One aspect of the present invention is the wireless communication system, wherein the antenna array including the antenna element to which the reflecting member is close, the wireless control device connected to the antenna array, and the reflecting member are used. A wireless communication device is configured.

One aspect of the present invention includes a first radio control device connected to a first antenna array including a plurality of antenna elements, and a second radio control device connected to a second antenna array including a plurality of antenna elements. , A wireless communication method in a wireless communication system including a reflecting member having a reflecting surface that reflects radio waves radiated by the antenna element, wherein the plurality of antenna elements have their respective phase centers in the same plane. It is located on the element plane, and the front surface of the first antenna array and the front surface of the second antenna array are parallel or substantially parallel, and the antenna element plane is the first and the first. It emits radio waves at a position perpendicular to or substantially perpendicular to the front surface of the second antenna array, and the reflecting member is surrounded by the phase center of the antenna element of the first and second antenna arrays. It is a position outside the quadrilateral region and is at least one of the antenna elements of the first and second antenna arrays, and is a midpoint between the first radio control device and the second radio control device. A part of the antenna located closer to one of the wireless control devices so that the reflecting surface is perpendicular to or substantially perpendicular to the plane of the antenna element and is located closer to the reflecting member. Of the radio radio waves radiated from the antenna element included in the array, the direct wave reaching the antenna element contained in the other antenna element at the diagonal position of the quadrilateral region and the reflected radio wave of the radio radio waves. This is a wireless communication method that reflects the radio wave so that the reflected wave that reaches the antenna element is synthesized in the opposite phase.

One aspect of the present invention includes a first radio control device connected to a first antenna array including a plurality of antenna elements, and a second radio control device connected to a second antenna array including a plurality of antenna elements. A wireless communication device in a wireless communication system including a reflecting member having a reflecting surface that reflects radio waves radiated by the antenna element, wherein the wireless communication device includes the first wireless control device and the reflection. The plurality of antenna elements including the members are located on the antenna element plane whose phase centers are the same plane, and the front surface of the first antenna array and the front surface of the second antenna array. The surface is parallel or substantially parallel, the antenna element plane is perpendicular to or substantially perpendicular to the front surface of the first and second antenna arrays, and the reflective member is the first and second antenna elements. A position outside the quadrilateral region surrounded by the phase center of the antenna element of the antenna array of 2, at least one of the antenna elements of the first and second antenna arrays, the first. The reflective surface is perpendicular to or substantially perpendicular to the plane of the antenna element at a position closer to one of the wireless control devices than the midpoint between the wireless control device and the second wireless control device, and the reflective member. Of the radio waves radiated from the antenna element included in a part of the antenna array located at a position close to the antenna element, the antenna element included in the other antenna array located at a diagonal position of the quadrilateral region. The plurality of antenna elements and the reflecting member are provided so that the arriving direct wave and the reflected wave of the radio wave reflected by the reflecting member and arriving at the antenna element are combined in opposite phases. It is a wireless communication device.

One aspect of the present invention is the wireless communication device, wherein there are a plurality of the reflective members, and the reflective members are located at positions close to each of the plurality of antenna elements included in the antenna array, or. Some of the reflective members are located closer to any of the antenna elements included in the first antenna array.

One aspect of the present invention is the wireless communication device, which absorbs the radio waves at a position between the antenna elements that block the radio waves radiated from some of the antenna elements and do not reach the reflecting member. It is further provided with an absorbing member.

One aspect of the present invention is the wireless communication device, wherein the reflecting member is positioned so that the reflecting surface is perpendicular to or substantially perpendicular to the front surface of the first and second antenna arrays. Or, the reflecting surface is tilted so as to face the direction of the antenna array existing at a position facing the front surface of the first and second antenna arrays from a position perpendicular to the front surface.

One aspect of the present invention is the wireless communication device, wherein the reflecting surface of the reflecting member is radiated from the antenna element of the own device and reflected by the reflecting surface at a diagonal position of the quadrilateral region. It has a size including a first Fresnel zone of a reflected wave reaching the antenna element included in the antenna array of the second radio control device.

According to the present invention, even when there is no ground between opposing antenna elements in a line-of-sight transmission line, the same frequency band can be used without widening the antenna element spacing in the antenna array without high-speed signal processing. Spatial multiplexing transmission can be performed.

It is a block diagram which shows the structure of the wireless communication system in 1st Embodiment. It is a figure which shows the structure of the wireless communication system in the same embodiment three-dimensionally. It is a block diagram which shows the structure of the wireless communication system in 2nd Embodiment. It is a block diagram which shows the structure of the wireless communication system in 3rd Embodiment. It is a block diagram which shows the structure of the wireless communication system in 4th Embodiment. It is a block diagram which shows the structure of the wireless communication system in 5th Embodiment. It is a block diagram (the 1) which shows the structure of the wireless communication system in 6th Embodiment. It is a block diagram (the 2) which shows the structure of the wireless communication system in 6th Embodiment. It is a block diagram which shows the other configuration example of the wireless communication system in 6th Embodiment. It is a graph which shows the difference of the reception level depending on the presence or absence of the inclination of the beam direction. It is a graph which shows the difference of SIR depending on the presence or absence of the inclination of the beam direction. It is a block diagram which shows the structural example of the wireless communication apparatus in 3rd Embodiment. It is a block diagram which shows the structure of the space division transmission wireless communication system. It is a block diagram which shows the structure of the space division transmission wireless communication system to which a phase shifter is applied. It is a block diagram which shows the structure of the parallel wireless transmission wireless communication system using the reflection by the earth.

(First Embodiment)
Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing a configuration of a wireless communication system 1 that performs parallel transmission according to the first embodiment of the present invention. The wireless communication system 1 includes wireless control devices 11 and 21, first and second antenna arrays 10, 20, and a reflector 30. Between the first and second antenna arrays 10 and 20, there is a line-of-sight transmission line. The wireless control devices 11 and 21 perform wireless signal processing in a high frequency band such as a millimeter wave band or a quasi-millimeter wave band. Further, the radio control devices 11 and 21 modulate the transmission signal as the radio signal processing, and based on the modulated transmission signal, the antenna elements 10-1, 10-2, 20-1, connected to each of them, Radio waves are transmitted through 20-2. Further, the wireless control devices 11 and 21 receive radio waves through the antenna elements 10-1, 10-2, 20-1 and 20-2 connected to each of the wireless signal processes, and receive the received radio waves. Demodulate and capture the received signal.

The first antenna array 10 includes antenna elements 10-1 and 10-2 connected to the wireless control device 11, and the second antenna array 20 includes antenna elements 20- connected to the wireless control device 21. Includes 1,20-2. The wireless control device 11, the antenna elements 10-1 and 10-2, and the reflector 30 are integrally configured as, for example, a wireless communication device. Further, the wireless control device 21 and the antenna elements 20-1 and 20-2 are integrally configured as, for example, a wireless communication device.

FIG. 2 is a three-dimensional view showing the configuration of the wireless communication system 1. As shown in FIGS. 1 and 2, the front surface 110 of the first antenna array and the front surface 210 of the second antenna array face each other in a parallel positional relationship, and the distance between the surfaces, that is, transmission. The distance is "D". Here, the front surface 110 of the first antenna array is the front surface of the antenna elements 10-1 and 10-2 included in the first antenna array 10, that is, the radio wave is transmitted without changing the direction of the beam. It is a plane perpendicular to the direction of radiation when it is radiated. The front surface 210 of the second antenna array is the front surface of the antenna elements 20-1 and 20-2 included in the second antenna array 20.

The phase centers of the antenna elements 10-1, 10-2, 20-1, 20-2 are installed on the same plane, and as shown in FIG. 2, the antenna elements 10-1, 10-2, 20- The quadrilateral-shaped antenna element plane region 300 surrounded by the phase centers of 1, 20-2 has a positional relationship perpendicular to the front surfaces 110 and 210 of the first and second antenna arrays. Here, the phase center is a point where the radio wave is apparently radiated or incident in the radiation or incident of the radio wave in the antenna element. In FIG. 1, for example, the antenna elements 10-1, 10-2, It is described assuming that there is a point at the center of phase at the tips of 20-1 and 20-2.

The reflecting plate 30 is a reflecting member that reflects radio waves, is outside the area of the antenna element plane region 300, and is one radio from the midpoint of the two radio control devices (radio control device 11 and radio control device 21). It is installed near the control device. In the first embodiment, the reflector 30 is located closer to the wireless control device 11. Further, the reflector 30 is installed so as to be perpendicular to the antenna element plane region 300 and to be perpendicular to the front surface 110 of the first antenna array.

In the wireless communication system 1, parallel transmission is performed by two wireless links between the antenna element 10-1 and the antenna element 20-1 and between the antenna element 10-2 and the antenna element 20-2. These two radio links are desired radio radio wave paths (hereinafter referred to as "desired wave paths"). On the other hand, the path between the antenna element 10-1 and the antenna element 20-2, which are in a diagonal positional relationship in the quadrilateral antenna element plane region 300, and the path from the antenna element 10-2 to the antenna element 20-1. The route between them is an unnecessary route (hereinafter, also referred to as “a route in which cross talk occurs”).

The broken line between the antenna elements 10-1 and 10-2 and the antenna elements 20-1 and 20-2 shown in FIG. 1 is a line indicating the path of the radio wave reflected by the reflecting surface of the reflecting plate 30. , These lines exist on the antenna element plane which is a plane including the antenna element plane region 300. For example, the radio wave radiated from the antenna element 10-1 is reflected at the reflection point 401 of the reflector 30 and reaches the antenna element 20-2.

For example, in FIG. 1, the antenna element plane, which is a plane including the antenna element plane region 300 surrounded by the phase centers of the antenna elements 10-1, 10-2, 20-1, and 20-2, and the first antenna array. The line of intersection with the front surface 110, that is, the straight line including the line segment between the phase centers of the antenna elements 10-1 and 10-2 is defined as the Y axis.

It is assumed that the intersection of the Y-axis and the reflector 30 is the origin, the line indicated by the reference numeral 301 perpendicular to the Y-axis is the X-axis, and the antenna element plane is the XY coordinate plane. At this time, the Y coordinate of the phase center of the antenna element 10-1 of the first antenna array 10 is "h ₁ ". The Y coordinate of the phase center of the antenna element 10-2 is "h ₂ ". The Y coordinate of the phase center of the antenna element 20-1 of the second antenna array 20 is "hd ₁ ", and the Y coordinate of the phase center of the antenna element 20-2 is "hd ₂ ".

A reflected wave that is radiated from the antenna element 10-1 and reflected once by the reflecting plate 30 to reach the antenna element 20-2, and a direct wave that is radiated from the antenna element 10-1 and directly reaches the antenna element 20-2. The antenna element 10-1 and the antenna element 20-2 are installed so as to cancel each other out in opposite phases.

The path of the direct wave from the antenna element 10-1 to the antenna element 20-2 is ((hd _2- h ₁ ) ² + D ² ) ^1/2 . The path of the reflected wave from the antenna element 10-1 to the antenna element 20-2 ((hd ₂ + h ₁ ) ² + D ² ) ^1/2 . Therefore, if the difference between the path of the reflected wave and the path of the direct wave represented by these equations is an odd multiple of the half wavelength of the radio wave, the direct wave and the reflected wave cancel each other out.

Further, the reflected wave that is radiated from the antenna element 10-1 and once reflected by the reflecting plate 30 and reaches the antenna element 20-1, and the reflected wave that is radiated from the antenna element 10-1 and directly reaches the antenna element 20-1. The antenna element 10-1 and the antenna elements 20-1 and 20-2 are installed so that the waves do not have the same phase or at least the opposite phase and a strong electric field point is generated at the phase center of the antenna element 20-1. Will be done.

The path of the direct wave from the antenna element 10-1 to the antenna element 20-1 is ((hd ₁ −h ₁ ) ² + D ² ) ^1/2 . The path of the reflected wave from the antenna element 10-1 to the antenna element 20-1 ((hd ₁ + h ₁ ) ² + D ² ) ^1/2 . Therefore, unless the difference between the reflected wave path and the direct wave path represented by these equations is an odd multiple of the half wavelength of the radio wave, the direct wave and the reflected wave do not have opposite phases, and the half wavelength If it is an even multiple, the direct wave and the reflected wave are in phase.

Similarly, the reflected wave radiated from the antenna element 10-2 and reflected once by the reflecting plate 30 to reach the antenna element 20-1, and the reflected wave radiated from the antenna element 10-2 and directly reach the antenna element 20-1. The antenna element 10-2 and the antenna element 20-1 are installed so that the direct waves that form the waves cancel each other out in opposite phases.

The path of the direct wave from the antenna element 10-2 to the antenna element 20-1 is ((hd ₁ −h ₂ ) ² + D ² ) ^1/2 . The path of the reflected wave from the antenna element 10-2 to the antenna element 20-1 ((hd ₁ + h ₂ ) ² + D ² ) ^1/2 . Therefore, if the difference between the path of the reflected wave and the path of the direct wave represented by these equations is an odd multiple of the half wavelength of the radio wave, the direct wave and the reflected wave cancel each other out.

Further, the reflected wave radiated from the antenna element 10-2 and once reflected by the reflecting plate 30 to reach the antenna element 20-2, and the reflected wave radiated from the antenna element 10-2 and directly reach the antenna element 20-2. The antenna element 10-2 and the antenna elements 20-1 and 20-2 are installed so that the waves do not have the same phase or at least the opposite phase and a strong electric field point is generated at the phase center of the antenna element 20-2. To.

The path of the direct wave from the antenna element 10-2 to the antenna element 20-2 is ((hd _2- h ₂ ) ² + D ² ) ^1/2 . The path of the reflected wave from the antenna element 10-1 to the antenna element 20-1 ((hd ₂ + h ₂ ) ² + D ² ) ^1/2 . Therefore, unless the difference between the reflected wave path and the direct wave path represented by these equations is an odd multiple of the half wavelength of the radio wave, the direct wave and the reflected wave do not have opposite phases, and the half wavelength If it is an even multiple, the direct wave and the reflected wave are in phase.

The reflector 30 is installed at a position closer to one of the wireless control devices than the midpoint of the two wireless control devices (radio control device 11 and wireless control device 21) while removing the radio waves of the unnecessary route as described above. As a configuration, in the wireless communication system 1, the position of the first antenna array 10 and the position of the second antenna array 20 are installed at different positions in the Y-axis direction. Hereinafter, the conditions for the positions of the first and second antenna arrays 10 and 20 will be described.

The reflection point 401 of the radio wave that is radiated from the antenna element 10-1 and reflected by the reflector 30 and reaches the antenna element 20-2 is represented as a position that internally divides the _{distance D by h 1 : hd 2. Here, assuming} that the ratio of the reflection positions is r ref, in the case of the antenna element 10-1 and the antenna element 20-2, r _ref = h ₁ / (h ₁ + hd ₂ ), and the front surface of the first antenna array. The position separated from 110 by D × r _ref , that is, the position of D × h ₁ / (h ₁ + hd ₂ ) is the position of the reflection point 401. This position is also a position D × (1-r _ref ) away from the front surface 210 of the second antenna array, that is, a position of D × hd ₂ / (h ₁ + hd ₂ ).

Therefore, in order to set the installation position of the reflector 30 closer to the wireless control device 11 than the midpoint of the two wireless control devices (wireless control device 11 and wireless control device 21) as shown in FIG. 1, h ₁ It is necessary that <hd ₂ and h ₂ <hd _1. Since h ₁ is a value smaller than _{h 2 and hd 2} is a value larger than _{hd 1 , h 1} and h ₂ are smaller than _{hd 1} and hd _2. the value of h ₂ -h _1, when the value of the hd 2 -hd ₁ are equal, the antenna element plane region 300 surrounded by the four antenna elements 10-1,10-2,20-1,20-2 Has a parallelogram shape.

Such values of h ₁ , h ₂ , hd ₁ , and hd _{2 of h 1} , h ₂ , hd ₁ , hd ₂ satisfying the condition that the direct wave and the reflected wave cancel each other out in the path where the crosstalk occurs described above. You need to choose from the values. Then, the reflector 30 is installed in a range including a position where _{the distance D is internally divided by h 1} : hd ₂ and a position where the distance D is _{internally divided by h 2} : hd _1.

Further, the size of the reflector 30 needs to be a size that sufficiently reflects radio waves. As shown in FIG. 1, when the radio waves radiated from the antenna elements 10-1 and 10-2 are reflected by the reflector 30 and reach the antenna elements 20-1 and 20-2, the reflection points 401 and other objects are used. The reflection points of the transmission path are concentrated in the reflection area 400. Further, at each reflection point, the energy of each radio wave is reflected in an area of a finite size surrounded by a circle having a radius of the first Fresnel zone. Therefore, the size of the reflector 30 needs to include at least a circle having a radius of the first Fresnel zone centered on each reflection point.

In the parallel transmission wireless communication system 802 shown in FIG. 15, the reflection area 870 where the reflection points are concentrated can be formed between the first antenna array 810 and the second antenna array 820. Therefore, when the ground 880 does not exist, the reflection area 870 is reflected. The board had to be installed manually. On the other hand, in the wireless communication system 1 of the first embodiment, the reflection area 400 is set in the two wireless control devices (radio control device 11 and wireless control device 21) by changing _{the ratio rref of the reflection position.} It can be moved to a position closer to the wireless control device 11 or a position closer to the wireless control device 21 than the point. Therefore, if it is installed at a position closer to the wireless control device 11 than the midpoint of the two wireless control devices (wireless control device 11 and wireless control device 21), the antenna elements 10-1, 10-2, and the wireless control device It is also possible to provide a wireless communication device including the 11 and the reflector 30 as a unit, and it is possible to eliminate the inconvenience of manually providing the reflector separately. However, in the wireless communication system 1, since the reflector 30 has a configuration that protrudes from the antenna elements 10-1 and 10-2, it is preferable to use it in an environment where there are no restrictions on such a configuration.

In the first embodiment described above, the antenna element 10-1 of the first antenna array 10 of the wireless control device 11 is approached from the midpoint of the two wireless control devices (radio control device 11 and wireless control device 21). Although it is installed in a vertical position, the reflector 30 is located closer to the antenna element 20-2 of the second antenna array 20 of the wireless control device 21 with the reflecting surface facing the antenna element 20-2. May be installed. That is, in the first embodiment, the reflector 30 has two wireless control devices (such as the antenna element 10-1 having the smallest Y coordinate value or the antenna element 20-2 having the largest Y coordinate value). It will be installed at a position closer to one of the wireless control devices than the midpoint between the wireless control device 11 and the wireless control device 21).

Further, in the first embodiment described above, the line of intersection between the antenna element plane and the front surface 110 of the first antenna array, that is, the line segment between the phase centers of the antenna elements 10-1 and 10-2 is defined. The included straight line is the Y-axis, but the Y-axis may be the line of intersection between the plane of the antenna element and the front surface 210 of the second antenna array. In that case, the Y-axis is a straight line including a line segment between the phase centers of the antenna elements 20-1 and 20-2.

(Second Embodiment)
FIG. 3 is a block diagram showing a configuration of the wireless communication system 2 according to the second embodiment. In FIG. 3, the same configurations as those in the first embodiment are designated by the same reference numerals, and different configurations will be described below. The wireless communication system 2 includes a first antenna array 10, a second antenna array 20, two reflectors 30-1, 30-2, and a shielding plate 40. Although the wireless control devices 11 and 21 shown in FIG. 1 are not shown in FIG. 3, the wireless control device 11 is connected to the antenna elements 10-1 and 10-2 as in the first embodiment. It is assumed that the wireless control device 21 is connected to the antenna elements 20-1 and 20-2.

The reflector 30-1 is installed at a position closer to the wireless control device 11 from the midpoint of the two wireless control devices (radio control device 11 and wireless control device 21) and closer to the antenna element 10-1. The reflector 30-2 is located closer to the wireless control device 11 from the midpoint of the two wireless control devices (radio control device 11 and wireless control device 21), and is closer to the antenna element 10-2. It is installed in the same position. The reflecting surfaces of the reflecting plate 30-1 and the reflecting plate 30-2 are installed perpendicular to the front surfaces 110 and 210 of the first and second antenna arrays.

The reflectors 30-1 and 30-2 are installed outside the antenna element plane region 300 surrounded by the phase centers of the antenna elements 10-1, 10-2, 20-1 and 20-2. That is, the line of intersection 301 between the antenna element plane including the antenna element plane region 300 surrounded by the phase centers of the antenna elements 10-1, 10-2, 20-1, and 20-2 and the reflecting surface of the reflecting plate 30-1. An XY coordinate plane is defined with -1 as the X-axis and the line of intersection between the antenna element plane and the front surface 110 of the first antenna array as the Y-axis. When the upper part of FIG. 3 is oriented in the positive direction of the Y-axis, the Y coordinate of the reflector 30-1 is smaller than the Y coordinate of the antenna element 10-1, and the Y coordinate of the reflector 30-2 is the antenna. It is larger than the Y coordinate of element 10-2.

The front surface 110 of the first antenna array and the front surface 210 of the second antenna array face each other in a parallel positional relationship, and the distance between the surfaces, that is, the transmission distance is “D”. The Y coordinate of the antenna element 20-1 is "h ₁ ", the Y coordinate of the antenna element 20-2 is "h ₂ ", and the antenna elements 10-1, 10-2, 20-1, 20-2 antenna element plane region 300 surrounded by the phase center, the height "(h 2 _{-h 1)",} width of a rectangular area of "D".

The shielding plate 40 is an absorbing member that absorbs radio waves, is located between the antenna elements 10-1 and 10-2, and is radiated from the antenna element 10-1 to reach the reflector 30-2. It is installed at a position that shields radio waves and shields radio waves that are radiated from the antenna element 10-2 and reach the reflector 30-1. These radio waves are unnecessary radio waves, and a shielding plate 40 having a sufficient size for shielding such radio waves is installed.

Next, looking at the conditions for installing the reflector 30-1, there are two conditions. The first condition is that the antenna element 10-1 is radiated and reflected once by the reflector 30-1, and the antenna element 20 is used. The reflected wave arriving at -2 and the direct wave radiated from the antenna element 10-1 and directly arriving at the antenna element 20-2 are arranged to have opposite phases. The second condition is the reflected wave radiated from the antenna element 10-1 and once reflected by the reflecting plate 30-1 to reach the antenna element 20-1, and the reflected wave radiated from the antenna element 10-1 and directly radiated from the antenna. The direct wave reaching the element 20-1 is not in phase or at least in the opposite phase, and a strong electric field point is generated at the phase center of the antenna element 20-1.

However, in the second embodiment, since the antenna element 10-1 and the antenna element 20-1 have the same height, as for the second condition, if the reflector 30-1 does not exist at the intermediate point, the reflected wave is generated. Does not occur. Therefore, in the second embodiment, the reflectors 30-1 and 30-2 are installed at positions closer to one of the wireless control devices than the midpoint of the two wireless control devices (radio control device 11 and wireless control device 21). In most cases it is not necessary to consider the reflected wave for the desired wave path. If it is necessary to consider, the path length of the direct wave is D, and the path length of the reflected wave is ((2h ₁ ) ² + D ² ) ^1/2 . If the difference between the path of the direct wave and the reflected wave is not an odd multiple of the half wavelength of the radio wave, the direct wave and the reflected wave will not be out of phase, and if it is an even multiple of the half wavelength, the direct wave and the reflected wave will not be in opposite phase. Are in phase.

A path that satisfies the first condition, that is, a reflected wave that is radiated from the antenna element 10-1 and once reflected by the reflector 30-1 to reach the antenna element 20-2, and a reflected wave that is radiated directly from the antenna element 10-1. The conditions of the path in which the direct waves reaching the antenna element 20-2 have opposite phases and cancel each other out will be described below.

Let the reflectance coefficients of the reflectors 30-1 and 30-2 be "+1". The reflection coefficient "+1" is, for example, a reflection coefficient when TM (Transverse Magnetic) is incident on a metal plate. When the reflectance coefficient is "+1", the phase of the wave does not change in the reflection by the reflectors 30-1 and 30-2.

The path of the direct wave radiated from the antenna element 10-1 and directly reaches the antenna element 20-2 is the path indicated by reference numeral 500 in FIG. The path length r _LOS of the direct wave is obtained by the following equation (1).

The path of the reflected wave that is radiated from the antenna element 10-1 and once reflected by the reflector 30-1 and reaches the antenna element 20-2 is the path to the reflection point 402 indicated by reference numeral 501, and is reflected. The path after passing through the point 402 is the path indicated by reference numeral 502. _{The path length r GR} of the reflected wave, which is the sum of the path lengths of the path 501 and the path 502, is obtained by the following equation (2).

Here, since the reflection coefficient is "+1" and there is no phase change due to reflection, if the difference between the above two path lengths is an odd multiple of the half wavelength of the radio wave, the phases are opposite and cancel each other out. Become. Therefore, by satisfying the following equation (3), the direct wave and the reflected wave have opposite phases.

In equation (3), N is a natural number and λ ₀ is the wavelength of the radio wave. Next, the condition of the position of the reflector 30-1 will be described. When the origin of the X-axis is the intersection of the X-axis and the front surface 110 of the first antenna array, the reflection point 402 is _{a position obtained by internally dividing D by h 1} : h ₂ , and thus the reflection point. The X coordinate "w" of 402 is obtained by the following equation (4).

The reflector 30-1 is installed so that the center position of the reflector 30-1 is w. As described in the first embodiment, the radio wave is not reflected at one point of the reflector 30-1, and most of the energy is a finite size surrounded by a circle having a radius of the first Fresnel zone 50. Reflects in the area. _{In obtaining the radius r 1} of the first Fresnel zone 50 at the reflection point 402 on the reflector 30-1 (hereinafter referred to as “Fresnel radius r ₁ ”), as shown in FIG. 3, a mirror image of the antenna element 10-1 is used as an antenna. A mirror image of the element 10-1i is defined.

The first Fresnel zone 50 has an elliptical shape with the phase center of the antenna element 20-2 as the long axis from the phase center of the mirror image 10-1i of the antenna element, and the length of the major axis of the ellipse is the path of the mirror image of the path 501. The total length is the path 501i and the path 502. Since the lengths of the path 501i and the path 501 are equal, the length of the major axis is equal to the path length r _GR of the reflected wave path. Here, assuming that the route length of the route 501i is d ₁ and the route length of the route 502 is d _{2 , the Fresnel radius r 1} in the first Fresnel zone 50 can be obtained by the following equation (5).

It should be noted that the relationship of the following equations (6) to (8) holds for _{d 1} and d _2.

Since the angle of incidence on the reflector 30-1 is φ _r , which is an angle of less than 90 degrees, the surface of the reflector 30-1 that contributes to the reflection of radio wave waves is the Frenel radius r _{1 at the reflection point 402.} The circle is inside the ellipse projected on the reflector 30-1. φr is _calculated by the following equation (9).

_{Therefore, an approximate value l 1} of half the length of the major axis of the ellipse projected on the reflector 30-1 by a circle having a Fresnel radius r ₁ can be obtained by the following equation (10).

The size of the reflector 30-1 is, for example, a size including a circular region having a diameter of _{2 × l 1 or more.} Regarding the reflector 30-2, since the difference between the Y coordinate of the phase center of the antenna element 10-2 and the Y coordinate of the reflector 30-2 is "h ₁ ", the position calculated for the reflector 30-1. The value of "w" indicating the size and _{the value of "l 1} " indicating the size can be applied as they are.

In the configuration of the second embodiment described above, the two reflectors 30-1 and 30-2 are connected to the wireless control device 11 from the midpoint of the two wireless control devices (wireless control device 11 and wireless control device 21). It is installed at a position closer to the antenna array 10 of 1. By installing in this way, the installation conditions for the reflector 30-1 can be determined by the positional relationship between the antenna element 10-1 and the antenna elements 20-1 and 20-2. Further, regarding the reflector 30-2, the installation conditions can be determined by the positional relationship between the antenna elements 10-2 and the antenna elements 20-1 and 20-2.

For example, assume a usage pattern in which a first antenna array 10 and a second antenna array 20 are installed on the roofs of two automobiles with the Y axis as the height direction. In the wireless communication system 1 of the first embodiment, the reflector 30 is located closer to one of the wireless control devices than the midpoint of the two wireless control devices (radio control device 11 and wireless control device 21) (for example, the first position). It is necessary to set the heights of the first antenna array 10 and the second antenna array 20 to different heights in order to install the antenna array 10 or the position closer to the second antenna array 20). It is not without the method of using two automobiles with different roof heights to match this difference in height, but it is not a usage form that can be universally applied to any automobile. On the other hand, in the wireless communication system 2 of the second embodiment, the heights of the first antenna array 10 and the second antenna array 20 can be made the same, so that the wireless communication system 2 can be used as if it is provided on the roof of an automobile. The configuration is suitable for the form.

(Third Embodiment)
FIG. 4 is a block diagram showing a configuration of the wireless communication system 3 according to the third embodiment. In FIG. 4, the same configurations as those of the first and second embodiments are designated by the same reference numerals, and different configurations will be described below. The wireless communication system 3 includes a first antenna array 10, a second antenna array 20, two reflectors 30-1, 30-2, and a shielding plate 40. Although the wireless control devices 11 and 21 shown in FIG. 1 are not shown in FIG. 4, the wireless control device 11 is connected to the antenna elements 10-1 and 10-2 as in the first embodiment. It is assumed that the wireless control device 21 is connected to the antenna elements 20-1 and 20-2.

Similar to the second embodiment, the reflectors 30-1 and 30-2 are outside the antenna element plane region 300 surrounded by the phase centers of the antenna elements 10-1, 10-2, 20-1 and 20-2. Therefore, they are installed at positions closer to the antenna elements 10-1 and 10-2, respectively.

The difference from the second embodiment is that the reflecting surface of the reflector 30-1 is not installed perpendicularly to the front surfaces 110 and 210 of the first and second antenna arrays, but is opposed to the first and second antenna arrays. It is a point that it is installed at an angle so as to face the direction of the antenna array 20 of 2. As shown in FIG. 4, the reflective surface of the reflector 30-1 is installed at an angle θ _r tilted clockwise from the vertical installation (hereinafter, also referred to as “argument”). Further, the reflecting surface of the reflector 30-2 is installed at an _{angle θ r} tilted counterclockwise from the installation perpendicular to the front surfaces 110 and 210 of the first and second antenna arrays. The angle θ _r is an angle of less than 90 degrees. The distance from the phase center of the antenna element 10-1 to the reflector 30-1 is "h ₁ ", and the distance from the phase center of the antenna element 10-2 to the reflector 30-2 is also "h ₁ ". is there.

The front surface 110 of the first antenna array and the front surface 210 of the second antenna array face each other in a parallel positional relationship, and the distance between the surfaces, that is, the transmission distance is “D”. The distance between the phase centers of the antenna elements 10-1 and 10-2 and the distance between the phase centers of the antenna elements 20-1 and 20-2 are "d", and the antenna elements 10-1 and 10-2, The antenna element plane region 300 surrounded by the phase centers of 20-1 and 20-2 is a rectangular region having a height of "d" and a width of "D".

A reflected wave that is radiated from the antenna element 10-1 and once reflected by the reflecting plate 30-1 and reaches the antenna element 20-2, and a direct wave that is radiated from the antenna element 10-1 and directly reaches the antenna element 20-2. The waves need to be out of phase with each other and cancel each other out. The conditions of the routes that cancel each other out in this way will be described below.

Let the reflectance coefficients of the reflectors 30-1 and 30-2 be "+1". The reflection coefficient "+1" is, for example, a reflection coefficient when TM is incident on a metal plate. When the reflectance coefficient is "+1", the phase of the wave does not change in the reflection by the reflectors 30-1 and 30-2.

_{The path length r LOS} of the path 503, which is the path of the direct wave radiated from the antenna element 10-1 and directly reaches the antenna element 20-2, is obtained by the following equation (11).

_{The path r GR} of the reflected wave that is radiated from the antenna element 10-1 and is once reflected at the reflection point 403 of the reflector 30-1 and reaches the antenna element 20-2 is obtained as follows. As shown in FIG. 4, a mirror image 10-1i of the antenna element is defined as a mirror image of the antenna element 10-1. The mirror image of the path 504 of the reflected wave is the path 504i, and the combined length of the path 504i and the path 505 is equal to _{the path r GR of the reflected wave.} The combined path of the path 504i and the path 505 is the hypotenuse of a right triangle. Therefore, the route r _GR is obtained by the following equation (12).

Here, since the reflection coefficient is "+1" and there is no phase change due to reflection, if the difference between the above two path lengths is an odd multiple of the half wavelength of the radio wave, the phases are opposite and cancel each other out. Become. Therefore, by satisfying the following equation (13), the direct wave and the reflected wave have opposite phases.

In equation (13), N is a natural number and λ ₀ is the wavelength of the radio wave. _{“H 1} ” and “d” are defined for the transmission distance “D” so as to satisfy the equation (13). The position of the reflector 30-1 is, for example, the reflection point 403 from the intersection of the perpendicular line drawn from the phase center of the antenna element 10-1 to the reflection surface of the reflection plate 30-1 and the reflection surface of the reflection plate 30-1. Distance to is indicated by "w". The distance "w" is calculated by the following equation (14).

In the equation (14), φ _rr is an angle represented by the following equation (15).

The reflector 30-1 will be installed at the position indicated by "w" calculated by the equation (14). Next, the size condition of the reflector 30-1 is obtained. Assuming that the length of the path 504 from the phase center of the antenna element 10-1 to the reflection point 403 is "d ₁ ", "d ₁ " is obtained by the following equation (16).

Assuming that the length of the path 505 from the reflection point 403 to the phase center of the antenna element 20-2 is "d ₂ ", "d ₂ " is obtained by the following equation (17).

_{The radius r 1} of the first Fresnel zone at the reflection point 403 can be obtained by substituting the calculated "d ₁ " and "d ₂ " into the equation (5). Contributing surface reflection wave of the radio wave in the reflector 30-1 becomes the circle of the Fresnel radius r ₁ and the ellipse projected in the reflecting plate 30-1 in the reflection point 403. _{The approximate value l 1} of half the length of the major axis of the ellipse obtained by projecting a circle with a Fresnel radius r ₁ onto the reflector 30-1 is obtained by the following equation (18).

The size of the reflector 30-1 is, for example, a size including a circular region having a diameter of _{2 × l 1 or more.} Since the positional relationship between the reflector 30-2 and the antenna element 10-2 is the same as that between the reflector 30-1 and the antenna element 10-1, the reflector 30-2 also has a reflector 30-1. A value of "w" indicating the calculated position and a _{value of "l 1} " indicating the size can be applied.

For example, when the transmission distance D is "10 m" and the radio frequencies are 60.48 GHz, h ₁ = 10 mm, d = 152 mm, and θ _r = 6.2 °, the conditions for canceling the equation (13) are satisfied. Is done. In this case, φ _rr = 7.2 °, w = 79 mm, l ₁ = 159 mm. Considering fixing the reflector 30-1 to, for example, the wireless control device 11, a reflector 30-1 having a length of _{w + l 1 = 238 mm is required.} In consideration of extending the reflecting plate 30-1 to the position that is connected to the antenna element 10-1 and the radio control apparatus 11, the length of w + _{l 1,} further the length of the antenna element 10-1 It will be the added length.

On the other hand, when the inclination is eliminated and θ _r = 0 °, this configuration becomes the wireless communication system 2 of the second embodiment, for example, D = 10 m, h ₁ = 20 mm, h ₂ = 625 mm. In the case of, the condition for canceling each other in the equation (3) is satisfied. In this case, w = 310 mm and l ₁ = 590 mm. That is, the size of the reflector 30-1 is w + l ₁ = 900 mm when considering fixing to the wireless control device 11, and the length is close to 1 m.

Further, even when D = 10 m, h ₁ = 10 mm, and h ₂ = 1260 mm, the conditions for canceling each other in the equation (3) are satisfied. In this case, w = 79 mm and l ₁ = 236 mm, the size of the reflector 30-1 can be reduced, but the distance between the antenna elements 10-1, 10-2 and the antenna elements 20-1, 20 can be reduced. The interval of -2 is 1250 mm. Therefore, the sizes of the first and second antenna arrays 10 and 20 exceed 1 m.

In contrast, in the wireless communication system 3 configuration of the third embodiment, the reflection plate 30-1 by giving an inclination theta _r, can reduce the size of the reflecting plate 30-1 and 30-2, and the The size of the 1st and 2nd antenna arrays 10 and 20 can be reduced. Therefore, the wireless communication system 1 of the third embodiment has a configuration suitable for an environment in which the size and weight of the wireless communication device are restricted in terms of the size and weight of the installation location.

Further, for example, when parallel transmission is performed with the directivity of the antenna using the millimeter-wave wireless LAN module shown in the reference below, when the half-value full width is 17 ° and the transmission distance is D = 10 m, for example, SIR. The distance between the antenna elements required to obtain (Signal to Interference Ratio) = 18db is d = 2.6m. On the other hand, when the wireless communication system 3 of the third embodiment is used, as described above, if h ₁ = 10 mm and θ _r = 6.2 °, then d = 152 mm, which is the configuration shown in the reference. The distance between the antenna elements can be significantly shortened as compared with the above.

References: Takaken Mizunuma, "[Requested Lecture] Millimeter Wave LAN Module Development Trends", Institute of Electronics, Information and Communication Engineers, March 2017, SRW2016-101, pp.183-188

In the configuration of the wireless communication system 1 of the first embodiment, the reflector 30 may be tilted as in the wireless communication system 3 of the third embodiment.

Further, also in the wireless communication system 3 of the third embodiment, the path of the desired wave, that is, between the antenna element 10-1 and the antenna element 20-1 depends on the angle at which the reflectors 30-1 and 30-2 are tilted. The path and the reflected wave of the path between the antenna element 10-2 and the antenna element 20-2 may be generated, which will be described in the fourth embodiment below.

(Fourth Embodiment)
FIG. 5 is a block diagram showing a configuration of the wireless communication system 4 according to the fourth embodiment. In FIG. 5, the same configurations as those of the first, second, and third embodiments are designated by the same reference numerals, and different configurations will be described below. Although the wireless control devices 11 and 21 shown in FIG. 1 are not shown in FIG. 5, the wireless control device 11 is connected to the antenna elements 10-1 and 10-2 as in the first embodiment. It is assumed that the wireless control device 21 is connected to the antenna elements 20-1 and 20-2.

The difference between the wireless communication system 4 and the wireless communication system 3 of the third embodiment is the length of the interval between the antenna elements 10-1 and 10-2, "d _T ", and the antenna elements 20-1, 20. The point is that the length of the interval of -2 is different from that of _{"d R".}

Here, the straight line including the line segment between the phase centers of the antenna elements 10-1 and 10-2 is defined as the Y axis, and the front surface 110 of the first and second antenna arrays from the phase center of the antenna element 10-1. The axis extending in the horizontal direction so as to be perpendicular to 210 is defined as the X axis. In this case, the antenna elements 10-1 and 10 so that the Y coordinate of the midpoint of the antenna elements 10-1 and 10-2 and the Y coordinate of the midpoint of the antenna elements 20-1 and 20-2 have the same value. -2, 20-1, 20-2 are installed. Therefore, the antenna element plane region 300 surrounded by the antenna elements 10-1, 10-2, 20-1, and 20-2 has an isosceles trapezoidal shape instead of a rectangular region.

Therefore, the value of the Y coordinate of the antenna element 20-2 represented by the reference numeral 600 in FIG. 5 is d _R − (d _R − d _T ) / 2 = (d _R + d _T ) / 2. Further, the length indicated by reference numeral 601 is 2h ₁ cos θ _r because the angle of inclination of the antenna element 10-1 is θ _r . The length indicated by reference numeral 602 is | (d _R − d _T ) / 2-2h ₁ cos θ _r |.

At this time, the path of the direct wave radiated from the antenna element 10-1 and directly reaches the antenna element 20-2 is indicated by the path 506, and the path length r _LOS of the path 506 is obtained by the following equation (19). ..

Further, the path of the reflected wave radiated from the antenna element 10-1 and once reflected by the reflector 30-1 to reach the antenna element 20-2 is indicated by the path 507 and the path 508. When the mirror image of the antenna element 10-1 is defined as the mirror image 10-1i of the antenna element, the combined path of the path 507i and the path 508 of the mirror image of the path 507 is the hypotenuse of a right triangle. Therefore, the path length r _GR of the reflected wave is obtained by the following equation (20).

Let the reflectance coefficients of the reflectors 30-1 and 30-2 be "+1". The reflection coefficient "+1" is, for example, a reflection coefficient when TM is incident on a metal plate. When the reflectance coefficient is "+1", the phase of the wave does not change in the reflection by the reflectors 30-1 and 30-2. Therefore, if the difference between the two path lengths is an odd multiple of the half wavelength of the radio wave, the phases are opposite to each other and cancel each other out. Therefore, by satisfying the following equation (21), the direct wave and the reflected wave have opposite phases.

In equation (21), N is a natural number and λ ₀ is the wavelength of the radio wave. _{“H 1} ”, “d _T ” and “d _R ” are defined for the transmission distance “D” so as to satisfy the equation (21).

In the case of the wireless communication system 4, a direct wave radiated from the antenna element 10-1 and directly reaches the antenna element 20-1, and a direct wave radiated from the antenna element 10-1 and once reflected by the reflector 30-1 and directly. The path to the reflected wave reaching the antenna element 20-1 is as follows. _{The path length r LOS} of the direct wave path 509 is expressed by the following equation (22).

Further, the path length r _GR of the reflected wave is the length of the path 510 from the mirror image 10-1i of the antenna element to the antenna element 20-1, and is obtained by the following equation (23).

Since the path from the antenna element 10-1 to the antenna element 20-1 is a path of a desired wave, the relationship shown in the following equation (24) needs to be established.

In equation (24), N is a natural number and λ ₀ is the wavelength of the radio wave. Incidentally, formula (24), for the direct wave and the reflected wave is a condition that does not reverse the phase, r _GR -r _LOS becomes a even multiple of lambda _0/2, the direct wave and the reflected wave is in phase Is more desirable.

In the case of a wireless communication system 3 of the third _embodiment, d R = for the _{d T, d} R = _{d T} Equation (22), third from the equation (24) by substituting (23) The conditions of the desired wave path in the wireless communication system 3 of the embodiment can be derived.

Further, with respect to the wireless communication system 4, the positions and sizes of the reflectors 30-1 and 30-2 can be obtained by the same method as that of the wireless communication system 3, and the reflectors 30-1 under the conditions obtained thereby can be obtained. , 30-2 will be provided.

(Fifth Embodiment)
FIG. 6 is a block diagram showing a configuration of the wireless communication system 5 according to the fifth embodiment. In FIG. 5, the same configurations as those of the first, second, and third embodiments are designated by the same reference numerals, and different configurations will be described below. Although the wireless control devices 11 and 21 shown in FIG. 1 are not shown in FIG. 6, the wireless control device 11 is connected to the antenna elements 10-1 and 10-2 as in the first embodiment. It is assumed that the wireless control device 21 is connected to the antenna elements 20-1 and 20-2.

The difference between the wireless communication system 5 and the wireless communication system 3 of the third embodiment is that the reflector 30-2, which is one of the two reflectors 30-1 and 30-2, has two wireless control devices. Prepare for a position closer to the antenna element 20-1 than a position closer to the antenna element 10-2 of the first antenna array 10 of the wireless control device 11 from the midpoint of (wireless control device 11 and wireless control device 21). It is a point that is being done.

Further, in order to prevent the radio waves radiated from the antenna element 20-2 from being reflected by the reflector 30-2, a shielding plate 40-2 is provided between the antenna element 20-1 and the antenna element 20-2. It is also different in that it is. The position of the shielding plate 40-1 is the same as that of the shielding plate 40 in the third and fourth embodiments.

The position and size conditions of the reflector 30-1 can be calculated by the same method as that of the wireless communication system 3 of the third embodiment. _{Further, the angle at which the reflector 30-2 is tilted is set to "θ r} ", which is the same as the angle of the reflector 30-1, as shown in FIG. 6, from the phase center of the antenna element 20-1 to the reflector 30-2. By setting the distance to "h ₁ ", the position and size conditions calculated for the reflector 30-1 can be applied to the reflector 30-2 as they are. The angle theta _r of tilt of the reflecting plate 30-1 and 30-2 may be 0 °. The state of θ _r = 0 ° is a state in which the reflectors 30-1 and 30-2 are not tilted, and the reflective surfaces of the reflectors 30-1 and 30-2 are in front of the first and second antenna arrays. This is a state in which the positional relationship is perpendicular to the surfaces 110 and 210.

Further, in FIG. 6, the reflector 30-1 is attached to the antenna element 10-1 of the first antenna array 10 of the wireless control device 11 from the midpoint of the two wireless control devices (radio control device 11 and wireless control device 21). The reflector 30-2 is located closer to the antenna element 20-1 of the second antenna array 20 of the wireless control device 21 from the midpoint of the two wireless control devices (radio control device 11 and wireless control device 21). Although it is located closer to, the reflector 30-1 is the antenna of the first antenna array 10 of the wireless control device 11 from the midpoint of the two wireless control devices (radio control device 11 and wireless control device 21). The reflector 30-2 is located closer to the element 10-2, and the reflector 30-2 is located at the midpoint of the two wireless control devices (radio control device 11 and wireless control device 21). It may be located closer to the antenna element 20-2. That is, the other reflector is installed on the antenna element included in the other antenna array located at the position of the adjacent vertex in the quadrilateral antenna element plane region 300 when viewed from the antenna element on which one reflector is located. become.

(Sixth Embodiment)
FIG. 7 is a block diagram showing a configuration of the wireless communication system 5 according to the sixth embodiment. In FIG. 7, the same configurations as those of the first, second, and third embodiments are designated by the same reference numerals, and different configurations will be described below.

The wireless communication system 6 shown in FIG. 7 includes antenna elements 20-3 and 20-4 in addition to the antenna elements 20-1 and 20-2 as the second antenna array 20. The antenna elements 20-1, 20-2, 20-3, and 20-4 are connected to the wireless control device 21a. Although the wireless control device 11 shown in FIG. 1 is not shown in FIG. 7, the wireless control device 11 is connected to the antenna elements 10-1 and 10-2 as in the first embodiment. And.

The distance between the antenna element 20-1 and the antenna element 20-3 is "Δd / 2", and the distance between the antenna element 20-2 and the antenna element 20-4 is "Δd / 2". Therefore, the distance between the antenna element 20-3 and the antenna element 20-4 is “d + Δd”.

Based on the equation (13) shown in the wireless communication system 3 of the third embodiment, the transmission distance D between the first and second antenna arrays 10 and 20 and the antenna elements 10-1 and 10-2 The optimum spacing between the antenna elements 10-1 and 10-2 and the spacing between the antenna elements 20-1 and 20-2 are "d" according to _{the spacing "h 1} " between the reflectors 30-1 and 30-2. The length of is fixed.

When the transmission distances D, h ₁ , and d satisfy the equation (13), the wireless control device 21a transmits and receives radio waves by using the antenna elements 20-1 and 20-2 according to the state shown in FIG. .. At this time, as shown in FIG. 8, when the transmission distance D changes to “D + ΔD”, it is necessary to increase the value of d so as to satisfy the equation (13). Therefore, the wireless control device 21a switches the antenna element 20-1 to the antenna element 20-3 and the antenna element 20-2 to the antenna element 20-4. As a result, the distance between the antenna elements of the second antenna array 20 can be increased to "d + Δd", which is the distance between the antenna elements 20-3 and the antenna elements 20-4.

As a condition for installing the antenna elements 10-1, 10-2, 20-3, 20-4 and the reflectors 30-1, 30-2, in the wireless communication system 4 of the fourth embodiment, D = D + ΔD. By setting d _T = d and d _R = d + Δd, conditions such as the positions of the reflectors 30-1 and 30-2 can be obtained. Therefore, by obtaining Δd corresponding to ΔD in advance based on the equation (21), the antenna elements 20-1 and 20-2 can be used for the antenna elements 20 even when the transmission distance increases to “D + ΔD”. By switching to -3 and 20-4, parallel transmission can be continuously performed.

In FIG. 7, the horizontal direction, that is, the direction of the line segment connecting the phase centers of the antenna elements 10-1 and the antenna element 20-1 is defined as the X axis, and the lines between the phase centers of the antenna elements 10-1 and 10-2. Let the straight line including the minute be the Y axis. In this case, the deviations of the first and second antenna arrays 10 and 20 in the Y-axis direction can be dealt with by using, for example, the wireless communication system 6a shown in FIG. In the wireless communication system 6a, the wireless control device 21b includes six antenna elements 20-1, 20-2, 20-1a, 20-2a, 20-1b, and 20-2b. The distance between the antenna elements 20-1 and 20-2, the distance between the antenna elements 20-1a and 20-2a, and the distance between the antenna elements 20-1b and 20-2b are all "d".

For example, when the first antenna array 10 is displaced downward along the Y axis, the wireless control device 21b sets the antenna elements 20-1 and 20-2 to the antenna elements 20-1a and 20-2a, respectively. Switch to. On the contrary, when the first antenna array 10 is displaced upward along the Y axis, the wireless control device 21b sets the antenna elements 20-1 and 20-2 to the antenna elements 20-1b and 20-, respectively. Switch to 2b.

As a result, among the antenna elements 20-1, 20-2, 20-1a, 20-2a, 20-1b, and 20-2b included in the second antenna array 20, the antenna element 10-of the first antenna array 10- Those located in front of 1, 10-2 can be selected and used. Therefore, the phase center of the antenna elements 10-1, 10-2 and the antenna element selected from the antenna elements 20-1, 20-2, 20-1a, 20-2a, 20-1b, 20-2b The antenna element plane region 300 surrounded by the phase center is a rectangular region. As a result, the state in which the equation (13) is satisfied can be maintained even if there is a deviation in the Y-axis direction, so that parallel transmission can be continuously performed.

Further, in the sixth embodiment described above, the detection of the position of the second antenna array 20 is performed by detecting a radio signal including a training signal generated and transmitted by the radio control device 11 connected to the first antenna array 10. It may be detected by using. Further, an optical distance measuring method using a camera or a laser provided on the first antenna array 10 side, a sound wave measuring method, or the like may be used.

Further, in the sixth embodiment described above, the antenna elements 20-1, 20-2, 20-3, 20-4, 20-1a, 20-2a, 20-1b, 20- by the wireless control devices 21a, 21b The switching of 2b may be electronic or mechanical.

Further, in the sixth embodiment described above, the wireless communication system 6 is configured to change the antenna element spacing of the second antenna array 20, but since the equation (13) may be satisfied, for example, the antenna element. The spacing between 10-1 and 10-2 may be changed, or the spacing between the antenna elements of both the first and second antenna arrays 10 and 20 may be changed.

Further, in the sixth embodiment described above, the parameters included in the equation (13) include the antenna elements 10-1 and 10-2 and the reflectors 30-1 and 30 in addition to the "d" of the antenna element spacing. The interval "h _{1 " of -1 and the angle "θ r} " for tilting the reflectors 30-1 and 30-2 are also included. Therefore, it _{has an electronic or mechanical configuration that changes "h 1} " and "θ _r ", and by changing these parameters, it is possible to cope with the deviation in the X-axis direction and the Y-axis direction. Good.

Further, when the reflectors 30-1 and 30-2 are made of metal, the reflectance coefficient is "+1" as described above in the case of TM incident, but the reflectance coefficient is "-" in the case of TE (Transverse Electric) incident. 1 ”. Therefore, the amount of change in the phase of the reflectors 30-1 and 30-2 can be changed by changing the polarization direction of the radio waves of the antenna elements 10-1 and 10-2. As a result, the direct wave and the reflected wave from the antenna element 10-1 to the antenna element 20-2 are in opposite phase, and the direct wave and the reflected wave from the antenna element 10-2 to the antenna element 20-1 are in opposite phase. May be satisfied.

(7th Embodiment)
In the second to sixth embodiments described above, the absolute value of the reflection coefficient of the reflectors 30-1 and 30-2 is "1", that is, only the phase relationship between the direct wave and the reflected wave is obtained in the state where there is no reflection loss. I was paying attention. On the other hand, due to the surface roughness of the reflectors 30-1 and 30-2 and the properties of the material, the antenna elements 10-1 and 10-2 have sharp directivity when the absolute value of the reflectance coefficient is smaller than "1". When, the amplitudes of the direct wave and the reflected wave are significantly different in the path where the crosstalk occurs. In that case, it is assumed that the direct wave and the reflected wave cannot sufficiently cancel each other.

FIG. 10 is a graph showing a change in reception level according to a transmission distance in the wireless communication system 3 according to the third embodiment. FIG. 10A is a graph when the direction of the radio wave beam radiated by the antenna elements 10-1 and 10-2 is directed to the front, and FIG. 10B is a graph when the antenna elements 10-1 and 10-2 are directed. It is a graph when the direction of the beam of the radio wave radiated by 10-2 is tilted by 6.2 ° from the front toward the direction of the reflectors 30-1 and 30-2. The horizontal axis is the transmission distance, and the unit is "m". The vertical axis represents the reception level of the antenna elements 20-1 and 20-2, and the unit is "dBm".

In FIGS. 10A and 10B, the solid line indicates the reception level in the desired wave path, that is, reception by the path from the antenna element 10-1 to the antenna element 20-1 and from the antenna element 10-2 to the antenna element 20-2. Indicates the level. The broken line indicates the reception level of the path on which crosstalk occurs, that is, the reception level of the path from the antenna element 10-1 to the antenna element 20-2 and from the antenna element 10-2 to the antenna element 20-1.

The value of the reception level is an integrated value of the received power within the band when the frequency band is 60.48 GHz and the bandwidth is 2.16 GHz. Regarding the antenna directivity of the wireless communication system 3, the half width of the main beam is set to 30 °. Further, as parameters that satisfy the condition of being suppressed by canceling the direct wave and the reflected wave in the path where crosstalk occurs, the transmission distance is D = 10 m, h ₁ = 10 mm, θ _r = 6.2 °, d =. It is set to 152 mm. Further, the reflection coefficients of the reflectors 30-1 and 30-2 are set to "+1". Since θ _r = 6.2 °, in the case of FIG. 10B, the beam directions of the antenna elements 10-1 and 10-2 are parallel to the reflecting surfaces of the reflectors 30-1 and 30-2. Become.

With reference to the reception level of the desired wave path at the transmission distance D = 10 m and the reception level of the path where crosstalk occurs, if there is no inclination in the beam direction in FIG. 10 (a), there is a large difference between the two reception levels. There is no. On the other hand, when the inclination is given in the beam direction shown in FIG. 10B, it can be seen that the reception level in the path where crosstalk occurs is suppressed.

11 (a) and 11 (b) show the SIR (signal to interference power ratio) calculated from the reception level of the desired wave path shown in FIGS. 10 (a) and 10 (b) and the path where crosstalk occurs, respectively. It is a graph shown. From FIG. 11A, the SIR is "4 dB" when there is no inclination in the beam direction, but from FIG. 11B, the SIR is "21 dB" when the inclination in the beam direction is given.

That is, in the wireless communication system 3 of the third embodiment, the antenna element spacing is d = 152 mm, that is, less than 200 mm in a state where a transmission distance D = 10 m and an SIR of 10 dB or more can be obtained. This is compared to the conventional parallel transmission, which requires about 2 m as the antenna element spacing in order to obtain an SIR of 10 dB or more when the transmission distance is D = 10 m and the beam width is 15 ° (using a q chip). It has a very compact configuration.

Also, as in the third embodiment described above, when given the inclination angle theta _r with respect to the reflecting plate 30-1 and 30-2, the transmission side of the antenna elements 10-1, 10-2 directivity Therefore, the amplitude difference between the direct wave and the reflected wave is likely to occur in the antenna elements 20-1 and 20-2 on the receiving side. In order to sufficiently cancel the direct wave and the reflected wave in the path where the crosstalk occurs, the antenna gain in the direction of radiation to the direct wave and the direction of radiation to the reflected wave should be equal, or the reflector plate. It is necessary to set the directivity of the antenna element so as to compensate for the reflection loss in 30-1 and 30-2.

The directivity of the antenna element is controlled, for example, by changing the direction in which the antenna elements 10-1 and 10-2 are installed, or by externally attaching a member that changes the directivity to the antenna elements 10-1 and 10-2. can do. Further, when a phased antenna array is used as the first antenna array 10, the directivity of the antenna element can be controlled by electronic control. However, it should be noted that when such directivity control is performed, the gain in the direction of the direct wave decreases to some extent.

Further, when two linearly polarized components, for example, both TE-incident and TM-incident polarization components are used, the reflector plate so that the phase rotation in the reflection at the time of glazing incident is 180 ° for both components. It is suitable to use a dielectric as the material of 30-1 and 30-2.

Also in the wireless communication system 1 of the first embodiment, the direction of the beam emitted by the antenna elements 10-1, 10-2, 20-1, and 20-2 may be variable, and the antenna element may also be used. The length between 10-1, 10-2 and the reflector 30 may be variable. Further, the intervals between the antenna elements 10-1 and 10-2 and the intervals between the antenna elements 20-1 and 20-2 may be variable, and the intervals between the antenna elements 10-1, 10-2, 20-1 and 20-2 may be variable. The position of the reflector 30 may be variable, and when the reflector 30 is tilted, the tilt angle may be variable.

In each of the above embodiments, for example, in the first embodiment, the first antenna array 10, the reflector 30, and the wireless control device 11 have been described as being configured as, for example, a wireless communication device. FIG. 12 is a block diagram showing a configuration example of a wireless communication device 100 on the side provided with reflectors 30-1 and 30-2 in the wireless communication system 3 of the third embodiment shown in FIG. 4, for example. In the wireless communication device 100, the wireless control device 11 is connected to the antenna elements 10-1 and 10-2, and the shielding plate 40 and the reflectors 30-1 and 30-2 are connected to the housing of the wireless control device 11. Is fixed. In the case of a configuration in which the inclination of the reflectors 30-1 and 30-2 can be changed, the wireless control device 11 has an electronic or mechanical configuration for changing the inclination of the reflectors 30-1 and 30-2. Will be provided.

In addition to the configuration shown in FIG. 12, the wireless communication device 100 may have the following configuration. For example, instead of fixing the reflectors 30-1 and 30-2 to the wireless control device 11, each of the reflectors 30-1 and 30-2 is fixed to the antenna elements 10-1 and 10-2. May be good. Further, the roots of the left ends of the reflectors 30-1 and 30-2 and the roots of the left ends of the shielding plate 40 are fixed to a member such as a rail, and the members are fixed to the wireless control device 11, and the reflector 30 is fixed. The configuration may be such that the −1, 30-2 and the shielding plate 40 are kept movable. Further, a flat surface plate having a positional relationship parallel to the plane of the drawing is fixed to, for example, the wireless control device 11. It is assumed that the surface plate has a surface that reflects less radio waves, for example, one having a low dielectric constant such as styrofoam, or one made of a radio wave absorber. Reflectors 30-1 and 30-2, shielding plates 40, and antenna elements 10-1 and 10-2 may be fixed to the surface plate to form a wireless communication device 100 integrally with the wireless control device 11.

In each of the wireless communication systems 1 to 6a in each of the above embodiments, the first antenna array 10 including the two antenna elements 10-1 and 10-2 and at least two antenna elements 20-1 and 20-2 are wireless. A second antenna array 20 capable of transmitting and receiving radio waves, and one reflecting plate 30 having a reflecting surface for reflecting radio waves, or two reflecting plates 30-1 and 30-2 are provided. The antenna elements 10-1, 10-2, 20-1, and 20-2 are installed so as to be located on the antenna element plane whose phase centers are the same plane, and the front surface of the first antenna array. The 110 and the front surface 210 of the second antenna array are parallel to each other, and the antenna element plane is installed so as to be perpendicular to the front surfaces 110 and 210 of the first and second antenna arrays. The reflectors 30, 30-1, and 30-2 are located outside the quadrilateral antenna element plane region 300 surrounded by the antenna elements 10-1, 10-2, 20-1, and 20-2. At least one of the positions (antenna elements 10-1, 10-2, 20-1, 20-2) closer to one of the wireless control devices than the midpoint of one wireless control device (radio control device 11 and wireless control device 21). It is installed so that the reflecting surface is perpendicular to the plane of the antenna element. When the antenna array installed at the position where the reflectors 30, 30-1 and 30-2 are close to each other is the first antenna array 10, the antenna elements 10-1, 10-2 included in the first antenna array 10 The direct wave that reaches the antenna elements 20-2 and 20-1 included in the second antenna array located at the diagonal position of the quadrilateral antenna element plane among the radio waves emitted by the antenna, and the reflection of the radio waves. Antenna elements 10-1, 10- so that the reflected waves that are reflected once by the plates 30, 30-1, 30-2 and reach the antenna elements 20-2, 20-1 are combined in the opposite phase. 2,20-1,20-2 and reflectors 30,30-1,30-2 are installed.

When performing wireless communication in the environment of a line-of-sight transmission line, the electric field strength is generated by superimposing the direct wave directly propagating between the transmitting and receiving antenna elements and the reflected wave by the reflecting plates 30, 30-1, 30-2 existing in the transmission line. Has the property of locally decreasing. Each of the wireless communication systems 1 to 6a in each of the above embodiments uses this property to perform parallel transmission of a plurality of data streams. Therefore, spatial multiplexing transmission by parallel transmission is possible without performing transmission beamforming, transmission line matrix feedback processing, and MIMO decoded signal processing. Further, in each of the wireless communication systems 1 to 6a, the reflectors 30, 30-1 and 30-2 are used as one wireless control device from the midpoint of the two wireless control devices (wireless control device 11 and wireless control device 21). Since it is installed at a closer position (a position closer to one of the antenna elements 10-1, 10-2, 20-1, 20-2), such reflectors 30, 30-1, 30-2 If parallel transmission can be performed by integrally installing the first or second antenna arrays 10 and 20, it is not necessary to additionally install a reflector, which is equipment other than the wireless communication device, in the transmission line. It becomes. As a result, even if there is no ground between the opposing antenna elements in the line-of-sight transmission line, space is used in the same frequency band without widening the antenna element spacing in the antenna array without high-speed signal processing. It is possible to perform multiplex transmission.

Further, even when a millimeter-wave wireless communication module in which the antenna element is integrated with the circuit is used, the external reflectors 30, 30-1, 30-2 and the shielding plates 40, 40-1, 40- By using 2, spatial multiplexing transmission by parallel transmission becomes possible. Further, in the second embodiment, the reflectors 30-1 and 30-2 are installed on each of the antenna elements 10-1 and 10-2 of the first antenna array 10, and the antenna element 10-1 is installed. By providing the shielding plate 40 between the antenna array 10 and 10, the reflecting plates 30-1 and 30-2 and the shielding plate 40 need to be installed only on the first antenna array 10 which is one of the antenna arrays. Therefore, a reflector is provided at an intermediate point between the first and second antenna arrays 10 and 20, and a reflector is provided on the antenna elements 10-1 and 10-2 of the first antenna array 10 and the second antenna array 20. It is not necessary to provide all of the antenna elements 20-1 and 20-2. Further, in the third embodiment, the size of the reflectors 30-1 and 30-2 required to obtain the required reception level of the reflected wave by further tilting the reflectors 30-1 and 30-2. Can be reduced. In this way, the reflectors 30, 30-1, 30-2 can be installed or reflected at a position closer to the wireless control device from the midpoint of the two wireless control devices (radio control device 11 and wireless control device 21). By tilting the angles of the plates 30, 30-1 and 30-2, parallel transmission in the same frequency band is possible even when the antenna element spacing cannot be widened, and frequency utilization efficiency is improved, that is, It is possible to increase the transmission speed and improve the transmission quality.

Further, in each of the above embodiments, the reflectance coefficients of the reflectors 30, 30-1, and 30-2 are not limited to "+1" and "-1", and may be any value, and the arbitrary reflection may be used. Depending on the value of the coefficient, the angle “θ _r ” for tilting the reflectors 30, 30-1, 30-2 and, for example, the condition of the path difference represented by the equation (13) are determined. For example, the reflectance coefficient can be changed by applying a material such as a metamaterial structure that changes the reflection phase as the material of the reflectors 30, 30-1, and 30-2.

Further, in each of the above embodiments, the antenna element plane region 300 surrounded by the antenna elements 10-1, 10-2, 20-1, and 20-2 may have a positional relationship perpendicular to the ground, or may have a positional relationship perpendicular to the ground. It may have a positional relationship parallel to. For example, the Y-axis defined in the first embodiment may indicate the height direction, the X-axis may indicate the direction horizontal to the ground, or the X-axis and the Y-axis may be 2 on the horizontal plane of the ground. It may indicate the direction. In the latter case, the reflector 30 is installed so that the reflecting surface is perpendicular to the ground.

Further, in the configuration of each of the above embodiments, it is assumed that the first antenna array 10 and the second antenna array 20 are installed in different automobiles, so that the positional relationship such as parallel or vertical is different. , It is not limited to the positional relationship that is exactly parallel or vertical, but also includes the positional relationship such as substantially parallel or substantially vertical that is slightly deviated. Even with a configuration in which such a deviation occurs, an effect substantially similar to the effect produced by the configuration of each of the above-described embodiments can be obtained.

The wireless control devices 11, 1, 21, 21a, 21b provided in the wireless communication systems 1, 2, 3, 4, 5, 6, 6a in each of the above-described embodiments may be realized by a computer. In that case, the program for realizing this function may be recorded on a computer-readable recording medium, and the program recorded on the recording medium may be read by the computer system and executed. The term "computer system" as used herein includes hardware such as an OS and peripheral devices. Further, the "computer-readable recording medium" refers to a portable medium such as a flexible disk, a magneto-optical disk, a ROM, or a CD-ROM, or a storage device such as a hard disk built in a computer system. Further, a "computer-readable recording medium" is a communication line for transmitting a program via a network such as the Internet or a communication line such as a telephone line, and dynamically holds the program for a short period of time. It may also include a program that holds a program for a certain period of time, such as a volatile memory inside a computer system that serves as a server or a client in that case. Further, the above program may be for realizing a part of the above-mentioned functions, and may be further realized for realizing the above-mentioned functions in combination with a program already recorded in the computer system. It may be realized by using a programmable logic device such as FPGA (Field Programmable Gate Array).

Although the embodiments of the present invention have been described in detail with reference to the drawings, the specific configuration is not limited to this embodiment, and includes designs and the like within a range that does not deviate from the gist of the present invention.

1 ... wireless communication system, 10 ... first antenna array, 10-1, 10-2 ... antenna element, 11 ... wireless control device, 20 ... second antenna array 20-1, 20-2 ... antenna element, 30 …a reflector

Claims (15)

A first antenna array containing multiple antenna elements,
A second antenna array containing multiple antenna elements,
A first wireless control device connected to the first antenna array,
A second wireless control device connected to the second antenna array,
A plurality of reflecting members having a reflecting surface for reflecting radio waves radiated by the antenna element, and
It is a wireless communication system equipped with
The plurality of antenna elements
Each phase center is located on the plane of the antenna element which is the same plane, and the front surface of the first antenna array and the front surface of the second antenna array are parallel or substantially parallel. , The plane of the antenna element is installed so as to be perpendicular to or substantially perpendicular to the front surface of the first and second antenna arrays.
The plurality of reflective members
An outer position of the quadrilateral area surrounded by the phase center of the antenna elements of the first and second antenna array, from the midpoint between said first antenna array and the second antenna array, It is installed at a position close to each of the plurality of antenna elements included in the first antenna array so that the reflecting surface is perpendicular to or substantially perpendicular to the plane of the antenna element.
A direct wave reaching the antenna elements included in the other A Ntenaare in the diagonal positions of the quadrilateral area of the radio wave radiated from the antenna element included in one of the A Ntenaare, of the radio waves A wireless communication system in which the plurality of antenna elements and the plurality of reflecting members are installed so that the reflected waves reflected by the reflecting member and reaching the antenna element are synthesized in opposite phases. A first antenna array containing multiple antenna elements,
A second antenna array containing multiple antenna elements,
A first wireless control device connected to the first antenna array,
A second wireless control device connected to the second antenna array,
A plurality of reflecting members having a reflecting surface for reflecting radio waves radiated by the antenna element, and
A plurality of absorbing members that absorb the radio waves, and
It is a wireless communication system equipped with
The plurality of antenna elements
Each phase center is located on the plane of the antenna element which is the same plane, and the front surface of the first antenna array and the front surface of the second antenna array are parallel or substantially parallel. , The plane of the antenna element is installed so as to be perpendicular to or substantially perpendicular to the front surface of the first and second antenna arrays.
The plurality of reflective members
An outer position of the quadrilateral area surrounded by the phase center of the antenna elements of the first and second antenna array, from the midpoint between said first antenna array and the second antenna array, The position closer to the antenna element included in the first antenna array and the reflecting member in the first antenna array among the antenna elements included in the second antenna array, respectively. in and with the antenna element and the quadrilateral region and closer to the antenna element to be adjacent position, the reflecting surface relative to the antenna element plane vertical or is disposed so as to be substantially perpendicular,
The plurality of absorbing members
In each of the first and second antenna arrays, the antenna that blocks radio waves radiated from the antenna element that the reflecting member does not approach and does not reach the reflecting member that exists at a position closer to the antenna array. Installed between the elements,
A direct wave reaching the antenna elements included in the other A Ntenaare in the diagonal positions of the quadrilateral area of the radio wave radiated from the antenna element included in one of the A Ntenaare, of the radio waves A wireless communication system in which the plurality of antenna elements and the plurality of reflecting members are installed so that the reflected waves reflected by the reflecting member and reaching the antenna element are synthesized in opposite phases. A first antenna array containing multiple antenna elements,
A second antenna array containing multiple antenna elements,
A first wireless control device connected to the first antenna array,
A second wireless control device connected to the second antenna array,
One reflecting member having a reflecting surface that reflects radio waves radiated by the antenna element, and
It is a wireless communication system equipped with
The plurality of antenna elements
Each phase center is located on the plane of the antenna element which is the same plane, and the front surface of the first antenna array and the front surface of the second antenna array are parallel or substantially parallel. , wherein the antenna element plane front surface perpendicular of said first and second antenna array, or is substantially perpendicular, said antenna element plane regarded as XY coordinate plane, which is included in the first a Ntenaare If the line including the line segment between the phase center of the antenna element and the Y-axis, the antenna value of the antenna elements of each Y-coordinate contained in the second a Ntenaare is included in the first a Ntenaare The element is installed so that it is smaller than the Y coordinate value of any of the elements.
The reflective member is
From the midpoint between the first antenna array and the second antenna array, which is a position outside the quadrilateral region surrounded by the phase center of the antenna element of the first and second antenna arrays. The reflection surface is perpendicular to or substantially perpendicular to the plane of the antenna element at a position closer to the antenna element having the largest value of the Y coordinate or the antenna element having the smallest value of the Y coordinate. Installed and
Of the radio waves radiated from the antenna element included in one antenna array, the direct wave reaching the antenna element included in the other antenna array at the diagonal position of the quadrilateral region and the radio wave of the radio wave. A wireless communication system in which the plurality of antenna elements and the reflecting member are installed so that the reflected waves reflected by the reflecting member and reaching the antenna element are synthesized in opposite phases. The reflective member is
The reflecting surface is installed perpendicular to or substantially perpendicular to the front surface of the first and second antenna arrays , or the reflecting surface is placed on the front surface of the first and second antenna arrays. the inclined to face the direction of the antenna array and Ru are installed, the wireless communication system according to any one of claims 1 to 3 at the position facing the a vertical position against. The reflective surface of the reflective member is
Reflected wave reaches the antenna element included in said first of said included in the antenna array is radiated from the antenna element is reflected by the reflecting surface in the position of the diagonal of the quadrilateral region the second A Ntenaare The wireless communication system according to any one of claims 1 to 4 , which has a size including the first Fresnel zone of the above. The position of the antenna element, the distance between a plurality of the antenna elements included in the antenna array, or the distance between the antenna element and the reflecting member existing at a position closer to the antenna element, or the reflecting member. The wireless communication system according to any one of claims 1 to 5 , wherein the tilt angle of the antenna element or the direction of the beam of the radio wave radiated from the antenna element is variable. Any of claims 1 to 6 , wherein the wireless communication device is composed of the antenna array including the antenna element to which the reflecting member is close, the wireless control device connected to the antenna array, and the reflecting member. The wireless communication system according to one item. A first antenna array containing multiple antenna elements,
A second antenna array containing multiple antenna elements,
A first wireless control device connected to the first antenna array,
A second wireless control device connected to the second antenna array,
A plurality of reflecting members having a reflecting surface for reflecting radio waves radiated by the antenna element, and
It is a wireless communication method in a wireless communication system including
The plurality of antenna elements are located on an antenna element plane whose phase centers are the same plane, and the front surface of the first antenna array and the front surface of the second antenna array are parallel to each other. , Or, the antenna element plane is installed so as to be perpendicular to or substantially perpendicular to the front surface of the first and second antenna arrays to emit radio waves.
Wherein the plurality of reflecting members, said first and said a position outside the quadrilateral area surrounded by the phase center of the antenna element of the second antenna array, the first antenna array and the second antenna Installed so that the reflecting surface is perpendicular to or substantially perpendicular to the plane of the antenna element at a position closer to each of the plurality of antenna elements included in the first antenna array from the midpoint with the array. It is the direct wave reaches the antenna elements included in the other a Ntenaare in the diagonal positions of the quadrilateral area of the radio wave radiated from the antenna element included in one of the a Ntenaare, the radio A wireless communication method that reflects the radio wave so that the reflected wave that reaches the antenna element by reflecting the radio wave is synthesized in the opposite phase. A first antenna array containing multiple antenna elements,
A second antenna array containing multiple antenna elements,
A first wireless control device connected to the first antenna array,
A second wireless control device connected to the second antenna array,
A plurality of reflecting members having a reflecting surface for reflecting radio waves radiated by the antenna element, and
A plurality of absorbing members that absorb the radio waves, and
It is a wireless communication method in a wireless communication system including
The plurality of antenna elements are located on an antenna element plane whose phase centers are the same plane, and the front surface of the first antenna array and the front surface of the second antenna array are parallel to each other. , Or, the antenna element plane is installed so as to be perpendicular to or substantially perpendicular to the front surface of the first and second antenna arrays to emit radio waves.
Wherein the plurality of reflecting members, said first and said a position outside the quadrilateral area surrounded by the phase center of the antenna element of the second antenna array, the first antenna array and the second antenna From the midpoint with the array, the position closer to one of the antenna elements included in the first antenna array and the first antenna among the antenna elements included in the second antenna array, respectively. to a position close to the antenna element to be adjacent in the said antenna elements reflecting member is closer the quadrilateral area in the array, the reflective surface is perpendicular, or, to be substantially perpendicular to the antenna element plane It is provided as a direct wave reaching the antenna elements included in the other a Ntenaare in the diagonal positions of the quadrilateral area of the radio wave radiated from the antenna element included in one of the a Ntenaare The radio wave is reflected so that the reflected wave that reaches the antenna element by being reflected from the radio wave is synthesized in the opposite phase.
The plurality of absorbing members are installed at positions between the antenna elements in each of the first and second antenna arrays to block radio waves radiated from the antenna element to which the reflecting member does not approach. A wireless communication method in which the reflective member existing at a position close to the antenna array is not reached. A first antenna array containing multiple antenna elements,
A second antenna array containing multiple antenna elements,
A first wireless control device connected to the first antenna array,
A second wireless control device connected to the second antenna array,
One reflecting member having a reflecting surface that reflects radio waves radiated by the antenna element, and
It is a wireless communication method in a wireless communication system including
The plurality of antenna elements are located on an antenna element plane whose phase centers are the same plane, and the front surface of the first antenna array and the front surface of the second antenna array are parallel to each other. , Or, the antenna element plane is perpendicular to or substantially perpendicular to the front surface of the first and second antenna arrays, and the antenna element plane is regarded as an XY coordinate plane, and the first When a straight line including a line segment between the phase centers of the antenna elements included in the antenna array is defined as the Y axis, the Y coordinate value of each of the antenna elements included in the second antenna array is the first antenna element. It is installed so as to be smaller than the value of the Y coordinate of any of the antenna elements included in the antenna array and emits radio waves.
The reflecting member is located outside the position of the quadrilateral area surrounded by the phase center of the antenna elements of the first and second antenna array, and the first antenna array and the second antenna array The reflection surface is perpendicular to the antenna element plane or at a position closer to the antenna element having the largest Y-coordinate value or the antenna element having the smallest Y-coordinate value from the midpoint. It is installed so as to be substantially perpendicular, to the antenna elements included in the other a Ntenaare in the diagonal positions of the quadrilateral area of the radio wave radiated from the antenna element included in one of the a Ntenaare A wireless communication method that reflects the radio wave so that the direct wave that arrives and the reflected wave that reaches the antenna element by reflecting the radio wave are combined in opposite phases. A first antenna array containing multiple antenna elements,
A second antenna array containing multiple antenna elements,
A first wireless control device connected to the first antenna array,
A second wireless control device connected to the second antenna array,
A plurality of reflecting members having a reflecting surface for reflecting radio waves radiated by the antenna element, and
A wireless communication device in a wireless communication system including
The wireless communication device is
The first antenna array, the first wireless control device, and the plurality of reflective members are provided.
The plurality of antenna elements
Each phase center is located on the plane of the antenna element which is the same plane, and the front surface of the first antenna array and the front surface of the second antenna array are parallel or substantially parallel. , The plane of the antenna element is installed so as to be perpendicular to or substantially perpendicular to the front surface of the first and second antenna arrays.
The plurality of reflective members
An outer position of the quadrilateral area surrounded by the phase center of the antenna elements of the first and second antenna array, from the midpoint between said first antenna array and the second antenna array, It is installed at a position close to each of the plurality of antenna elements included in the first antenna array so that the reflecting surface is perpendicular to or substantially perpendicular to the plane of the antenna element.
A direct wave reaching the antenna elements included in the other A Ntenaare in the diagonal positions of the quadrilateral area of the radio wave radiated from the antenna element included in one of the A Ntenaare, of the radio waves A wireless communication device in which the plurality of antenna elements and the plurality of reflecting members are installed so that the reflected waves reflected by the reflecting member and reaching the antenna element are synthesized in opposite phases. A first antenna array containing multiple antenna elements,
A second antenna array containing multiple antenna elements,
A first wireless control device connected to the first antenna array,
A second wireless control device connected to the second antenna array,
A plurality of reflecting members having a reflecting surface for reflecting radio waves radiated by the antenna element, and
A plurality of absorbing members that absorb the radio waves, and
A wireless communication device in a wireless communication system including
The wireless communication device is
The first antenna array, the first wireless control device, the reflection member, and the absorption member are provided.
The plurality of antenna elements
Each phase center is located on the plane of the antenna element which is the same plane, and the front surface of the first antenna array and the front surface of the second antenna array are parallel or substantially parallel. , The plane of the antenna element is installed so as to be perpendicular to or substantially perpendicular to the front surface of the first and second antenna arrays.
The plurality of reflective members
An outer position of the quadrilateral area surrounded by the phase center of the antenna elements of the first and second antenna array, from the midpoint between said first antenna array and the second antenna array, The position closer to the antenna element included in the first antenna array and the reflecting member in the first antenna array among the antenna elements included in the second antenna array, respectively. in and with the antenna element and the quadrilateral region and closer to the antenna element to be adjacent position, the reflecting surface relative to the antenna element plane vertical or is disposed so as to be substantially perpendicular,
The plurality of absorbing members
In each of the first and second antenna arrays, the antenna that blocks radio waves radiated from the antenna element that the reflecting member does not approach and does not reach the reflecting member that exists at a position closer to the antenna array. Installed between the elements,
A direct wave reaching the antenna elements included in the other A Ntenaare in the diagonal positions of the quadrilateral area of the radio wave radiated from the antenna element included in one of the A Ntenaare, of the radio waves A wireless communication device in which the plurality of antenna elements and the plurality of reflecting members are installed so that the reflected waves reflected by the reflecting member and reaching the antenna element are synthesized in opposite phases. A first antenna array containing multiple antenna elements,
A second antenna array containing multiple antenna elements,
A first wireless control device connected to the first antenna array,
A second wireless control device connected to the second antenna array,
One reflecting member having a reflecting surface that reflects radio waves radiated by the antenna element, and
A wireless communication device in a wireless communication system including
The wireless communication device is
The first antenna array, the first wireless control device, and the reflection member are provided.
The plurality of antenna elements
Each phase center is located on the plane of the antenna element which is the same plane, and the front surface of the first antenna array and the front surface of the second antenna array are parallel or substantially parallel. , The antenna element plane is perpendicular to or substantially perpendicular to the front surface of the first and second antenna arrays, the antenna element plane is regarded as an XY coordinate plane, and the said antenna element plane is included in the first antenna array. When a straight line including a line segment between the phase centers of the antenna elements is defined as the Y axis, the Y coordinate value of each of the antenna elements included in the second antenna array is the antenna included in the first antenna array. The element is installed so that it is smaller than the Y coordinate value of any of the elements.
The reflective member is
An outer position of the quadrilateral area surrounded by the phase center of the antenna elements of the first and second antenna array, from the midpoint between said first antenna array and the second antenna array, The reflection surface is perpendicular to or substantially perpendicular to the plane of the antenna element at a position closer to the antenna element having the largest value of the Y coordinate or the antenna element having the smallest value of the Y coordinate. Installed and
A direct wave reaching the antenna elements included in the other A Ntenaare in the diagonal positions of the quadrilateral area of the radio wave radiated from the antenna element included in one of the A Ntenaare, of the radio waves A wireless communication device in which the plurality of antenna elements and the reflecting member are installed so that the reflected waves reflected by the reflecting member and reaching the antenna element are synthesized in opposite phases. The reflective member is
The reflecting surface is installed perpendicular to or substantially perpendicular to the front surface of the first and second antenna arrays , or the reflecting surface is placed on the front surface of the first and second antenna arrays. Ru is disposed inclined to face the direction of the antenna array at the position opposite from the vertical position for, wireless communication apparatus according to any one of claims 11-13. The reflective surface of the reflective member is
Reflected wave reaches the antenna element included in said first of said included in the antenna array is radiated from the antenna element is reflected by the reflecting surface in the position of the diagonal of the quadrilateral region the second A Ntenaare The wireless communication device according to any one of claims 11 to 14 , which has a size including the first Fresnel zone of the above.

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