JP2004056457A - Wireless transmission system, radio transmission method, and antenna assembly - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enable each home of a collective housing to receive various types of broadcast programs without wiring at a receiver located in each home when each home receiver can receive radio waves emitted from a millimeter wave transmitter installed on a roof, etc. for transmitting various types of broadcast signal including BS broadcast signal. <P>SOLUTION: Antennas 31, 32 and 33 for receiving various sorts of broadcast programs are installed on the roof of the collective housing 20, and signals received at the antennas are supplied to a millimeter wave transmitter 22. Radio waves of a millimeter wave band from the millimeter wave transmitter 22 are received at a millimeter wave receiver 23, and the received signals are received by each home of the collective housing. Each home can view a broadcast program based on a wireless transmission system. Such millimeter waves are transmitted even to an adjacent building 34 and to separate houses 35B and 35C. Thus, a problem that the other housing or houses can hardly receive the radio waves can be solved. In each home, radio waves from the transmitter 22 are reflected by a reflector or are received by a receiving antenna mounted outside or inside the window pane of the home to wirelessly receive the signals indoors. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a wireless transmission system, a wireless transmission method, and an antenna device suitable for being applied to a millimeter wave band.
[0002]
[Prior art]
In Japan, various broadcasting media such as BS digital broadcasting, CS digital broadcasting, and CATV have become widespread, and in the future, with the progress of digitalization, the spread and development of broadcasting media are expected to be more and more widespread. On the other hand, there are factors that hinder the spread of these broadcast media. Obstacles in each home include wiring complexity. In order to view a plurality of broadcast media, a tuner for each broadcast media is required, and indoor wiring becomes complicated.
[0003]
As means for solving the problem of home wiring, a millimeter-wave video multiplex transmission system has been proposed. In the millimeter wave band (radio waves of 30 to 300 GHz, wavelength of 1 to 10 mm), transmission of a wideband signal such as a video signal can be performed by a small communication device. In particular, the 60 GHz band is a license-free band, and is suitable for a wireless transmission system limited to a small area with a radius of about several tens of meters due to the characteristic that radio waves do not reach far and interference does not easily occur. That is, it is possible to wirelessly transmit a broadband signal obtained by multiplexing video signals of various broadcast media, and since radio waves pass through glass, shoji, inner walls, etc., a receiver can be installed in an adjacent room. In addition, the nature of the high propagation attenuation allows for closed wireless services without interference with other systems outdoors.
[0004]
A television video transmission system as shown in FIG. 1 has been proposed utilizing such features. In FIG. 1, an antenna for receiving various television broadcasts is installed at home. That is, an antenna 1 for receiving terrestrial broadcasting, an antenna 2 for receiving CS broadcasting, and an antenna 3 for receiving BS broadcasting are provided. The reception signals of these antennas 1, 2, and 3 are supplied to a millimeter-wave transmitter 4 installed in the home.
[0005]
Further, an antenna 5 for FWA (Fixed Wireless Access) is also provided. The antenna 5 is for a wireless LAN (Wireless Local Area Network), and is a 2.4 GHz band wireless LAN system conforming to IEEE802.11b, a 5 GHz band wireless LAN system conforming to IEEE802.11a, and a 25 GHz band wireless LAN. It is possible to communicate in a system or the like. A radio base station 6 is connected to the antenna 5.
[0006]
At home, an STB (Set-top Box) 7 and a television receiver 8 connected to the STB 7 are installed. The television receiver 8 can receive a CATV (Cable Television) service, and is connected to the Internet via an ADSL (Asymmetric Digital Subscriber Line).
[0007]
In the system of FIG. 1, various television broadcasts can be viewed by receiving a millimeter wave, for example, a 60 GHz band radio wave transmitted from the millimeter wave transmitter 4 by the wall-mounted television receiver 9 or the like. In order to expand the indoor reception area, a repeater 10 is provided as needed.
[0008]
As described above, the television broadcast signals received by the outdoor antennas 1, 2, and 3 are retransmitted indoors using radio waves in the 60 GHz band, so that the antenna and the tuner can be connected without being connected by a feeder line. TV broadcast can be viewed and the degree of freedom of the installation location of the television receiver can be improved.
[0009]
[Problems to be solved by the invention]
The system shown in FIG. 1 provides an indoor wireless transmission system, and cannot solve the problem of television viewing in an apartment house. In other words, in the housing complex, BS-IF wiring is not provided, there is no veranda in the southwest, antenna installation is difficult, and there are buildings that block the southwest direction. There is a situation that cannot receive service. In addition, in a multi-family house, even if it is desired to draw in a cable broadcast such as CATV, there is a current situation in which it is not possible to draw in due to costs such as wiring construction costs for each household.
[0010]
Therefore, an object of the present invention is to provide a wireless transmission system, a wireless transmission method, and an antenna device that can solve a problem related to television viewing in a building where a plurality of residents are present, such as an apartment house and a building.
[0011]
[Means for Solving the Problems]
In order to solve the above-mentioned problem, the invention of claim 1 installs a millimeter-wave transmitter on the roof or the upper floor of a building, and uses the millimeter-wave transmitter to convert a broadcast media signal downward as a millimeter-wave charged wave. A wireless transmission system that emits and transmits a millimeter-wave charged wave wirelessly to a resident of a building.
[0012]
In one embodiment of the present invention, a reflector is used to direct the traveling direction of the radio wave radiated from the millimeter wave transmitter to each resident's room. By selecting the reflectivity of the reflector, a difference in reception level caused by a difference in distance between the millimeter wave transmitter and each of the plurality of reflectors is corrected. By selecting the installation position of the reflector, the difference in the reception level is corrected.
[0013]
In another aspect of the present invention, a receiving antenna is provided for each resident to receive radio waves from a millimeter-wave transmitter. The receiving antenna is mounted on the indoor side or the outdoor side of a plate that separates the outdoor and the indoor. The millimeter wave signal received by the receiving antenna is re-radiated indoors by the transmitting antenna. By selecting the installation position of the receiving antenna or selecting the material of the cover of the receiving antenna, the difference in the reception level caused by the difference in the distance between the millimeter wave transmitter and each of the plurality of receiving antennas is corrected. .
[0014]
Furthermore, the present invention relates to an antenna device that receives a millimeter-wave charged wave outdoors and re-radiates a received signal indoors, wherein an end of a receiving antenna is attached to one surface of a plate separating indoors and outdoors, In the antenna device, the end of the transmitting antenna is attached to a position substantially coincident with the end of the receiving antenna.
[0015]
Still further, the present invention provides an antenna device that receives a millimeter-wave charged wave outdoors and re-radiates a received signal indoors, wherein a core wire penetrates a board separating indoors and outdoors, and two coaxial connectors are provided from both sides of the board. This is an antenna device in which a receiving antenna and a transmitting antenna are connected to each other via a core wire and two coaxial connectors.
[0016]
According to the present invention, a millimeter-wave transmitter is installed on the roof or the upper floor of a building such as an apartment house, and a broadcast signal received by a common antenna is converted into a millimeter-wave band signal and radiated. Broadcast media can be wirelessly transmitted to each resident by receiving by the receiving unit.
[0017]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of the present invention will be described. A wireless transmission system provided by the present invention for solving a viewing problem in a building where a plurality of residents are present, such as an apartment house, will be referred to as a vertical wiring system. A vertical wiring system is a wireless connection between the rooftop or the upper floor of a building and each occupant in the vertical direction using millimeter wave radio waves to transmit various multimedia signals such as satellite broadcasting. This is a system for transmitting data to tenants. The vertical wiring system has a feature that a low-cost connection service can be realized because it is not necessary to newly lay a wiring such as an optical fiber and a coaxial cable in an apartment house.
[0018]
FIG. 2 shows an example of a vertical wiring system to which the present invention is applied. Reference numeral 20 denotes, for example, a three-story apartment house, for example, in which a stair space is provided at a central position of the building. A total of six houses are provided, one on each side of the central location. A veranda 21 is provided for each resident.
[0019]
A millimeter wave transmitter 22 is installed near the center of the roof of the apartment house 20. For example, a millimeter wave in a 60 GHz band is used. A common antenna for television broadcast reception is installed on the roof, and the output of the antenna is supplied to the millimeter wave transmitter 22. The millimeter-wave transmitter 22 includes an up-converter that up-converts a television signal received by a television antenna to a 60-GHz band millimeter-wave signal, and a transmission antenna, and transmits the up-converted signal substantially vertically downward with the transmission antenna. Radiate. On the other hand, each resident is provided with a receiving unit 23, and an output signal of the receiving unit 23 is drawn into each resident's room.
[0020]
In the vertical wiring system described above, the millimeter wave transmitter 22 is installed on the roof of an apartment house, and the receiving unit 23 is installed for each resident, so that each home can receive broadcast waves. This vertical wiring system eliminates the need to newly lay wiring such as an optical fiber and a coaxial cable in an apartment house, and can realize a low-cost connection service. Also, since the millimeter wave radio waves can transmit a wide band signal, it is possible to introduce a CATV or an Internet line to each home, and it is possible to transmit a multimedia signal.
[0021]
FIG. 3 shows a configuration example of a system obtained by further expanding the vertical wiring system. An antenna 31 for receiving terrestrial broadcasting, an antenna 32 for receiving CS broadcasting, and an antenna 33 for receiving BS broadcasting are installed on the roof of the apartment house 20. The reception signals of these antennas 31, 32 and 33 are supplied to the millimeter wave transmitter 22. The millimeter wave band radio wave from the millimeter wave transmitter 22 is received by the millimeter wave receiver 23, and the received signal is taken into each resident's room.
[0022]
Reference numeral 40 indicates each resident. The radio wave in the millimeter wave band is taken into the premises of the resident 40 via the receiving unit 23. A millimeter-wave transmitter 41 that re-radiates the millimeter-wave charged wave received by the reception unit 23 indoors is installed inside the resident 40. Millimeter-wave charged waves from the transmitter 41 are received by a receiver attached to the wall-mounted television receiver 42, the liquid crystal television receiver 43, and the like. As a result, the resident 40 can receive television broadcasts such as terrestrial broadcasts, CS broadcasts, BS broadcasts, and CATV, and can access the Internet.
[0023]
Further, on the roof of the apartment house 20, other millimeter-wave transmitters 22A and 22B are installed. The transmitter 22A transmits a millimeter-wave charged wave to a millimeter-wave receiver 23A installed on the roof of another building (a multi-family house, a building, or the like) 34 adjacent to the multi-family house 20. In the other building 34, various television broadcasts can be viewed and the Internet can be accessed in the same manner as in the multi-dwelling house 20 by the indoor wireless transmission system using radio waves in the millimeter wave band installed in the building. Can be. In the present invention, the signal received by each resident may be transmitted to each device not only by the millimeter-wave band wireless transmission system but also by an installed wireless or wired system.
[0024]
A radio wave radiated from another millimeter-wave transmitting unit 23B installed on the roof of the apartment house 20 has a millimeter-wave receiver 23B installed on the roof of the detached house 35B and a millimeter installed on the roof of the detached house 35C. The signal is received by the wave receiving unit 23C. Various television broadcasts can be viewed and the Internet can be accessed through a millimeter-wave band wireless transmission system installed in each home. As described above, the antennas 31, 32, and 33 can be shared by the residents of a plurality of buildings, and the satellite broadcasting can be received even in a location where the satellite broadcasting cannot be received due to a location or a newly constructed building. Becomes possible.
[0025]
In the above-described vertical wiring system, several configuration examples for each resident to receive millimeter-wave band radio waves radiated from the transmitter 22 installed on the roof will be described. The example illustrated in FIG. 4 is an example in which the receiving unit 23 includes the reflector 51. The number of reflectors 51 equal to the number of houses is installed. As shown in an enlarged manner in FIG. 4, the reflector 51 includes a metal reflector 52 and a mounting portion 53 for supporting the reflector 52 and mounting it on the veranda 21 or the like.
[0026]
The traveling direction of the millimeter wave band radio wave radiated downward from the transmitter 22 installed on the roof of the apartment house 20 is bent at a substantially right angle by the reflector 51 and radiated toward each house. In many cases, in the apartment house 20, the outside and the inside are often separated by a glass window. Radio waves in the millimeter-wave band can pass through glass with a relatively small transmission loss of about 2 dB. Therefore, the signal can be transmitted indoors with little attenuation. The wireless transmission system as described above is installed indoors. The radio wave reflected by the reflector 51 is received by the indoor receiving antenna, and is re-emitted by the transmitting antenna.
[0027]
In the vertical wiring system, the transmitter 22 is installed on the rooftop or the top floor, so that the higher the floor, the higher the reception level. Since the reception level is excessive, problems such as signal saturation occur. On the lower floor, the reception level is too low and the noise increases. Therefore, the variation of the reception level related to the distance between the millimeter wave transmitter 22 and the receiving unit 23 is corrected.
[0028]
In the example in which the reflector 51 shown in FIG. 4 is used, the reflectance of the reflector 52 corrects the variation in the reception level. The reflectivity differs depending on the type of metal material forming the reflection plate 52. For example, an aluminum plate has a higher reflectance than a stainless steel plate. A reflector 51 made of a metal having a low reflectance is installed on an upper floor, while a reflector 51 made of a metal having a high reflectance is installed on a lower floor. Further, an antireflection film may be attached to reduce the reflectance.
[0029]
As described later, the radio wave reflected by the millimeter wave transmitter 22 or the reflector 51 is received by the receiving antenna. Usually, a receiving antenna is provided with a cover that covers the antenna. This cover is made of a synthetic resin. The reflectance can be changed by changing the thickness of the cover or attaching a radio wave absorber to the cover. A plurality of methods for correcting the difference in reception level described above may be combined.
[0030]
When an antenna having a directivity as shown in FIG. 5 is used as the antenna of the millimeter-wave transmitter 22, the reflector 51 on the lower floor is installed so as to be located immediately below the antenna, and the reflector on the upper floor is installed. Reflector 51 is installed at a position slightly shifted from directly below the antenna. This makes it possible to correct the variation in the reception level due to the difference in the distance between the antenna of the transmitter 22 and the reflector 51.
[0031]
Next, a configuration using a receiving antenna as the receiving unit 23 will be described. First, the configuration of the glass-attached antenna will be described. FIG. 6 shows an arrangement in which a receiving antenna 62, an amplifier 63, a transmitting antenna 64 and a battery power supply 65 for the amplifier 63 are arranged on the indoor side of the glass 61. As the receiving antenna 62, an antenna having a thin and planar shape and attached to the glass 61, for example, a microstrip antenna is used. Further, an active antenna in which the amplifier 63 is incorporated in the receiving antenna 62 may be used. Specifically, an amplified active integrated antenna in which the antenna and the amplifying element are integrated on the same substrate can be used.
[0032]
The configuration shown in FIG. 6 is suitable for a case where a radio wave is vertically incident on the surface of the glass 61. It can be used in combination with the reflector 51 described above. By re-radiating the millimeter wave charged wave indoors, an indoor wireless transfer system can be realized. For this re-radiation, an amplifier 63, a transmitting antenna 64, and a battery power supply 65 are provided. As the transmission antenna 64, a wide directivity antenna, for example, a microstrip antenna is used in order to increase the degree of freedom of the installation position of the indoor television receiver.
[0033]
FIG. 7 shows another example of a glass-attached antenna. In the configuration of FIG. 7, the millimeter wave charged wave from the transmitter 22 installed on the roof of the apartment house 20 or the radio wave reflected by the reflector 51 is received by the receiving antenna 66 installed outside the glass 61, that is, outside. Is received. The indoor transmission antenna 64 is coupled with the glass 61 therebetween.
[0034]
FIG. 8A shows a state where the receiving antenna 66 and the transmitting antenna 64 are installed with the glass 61 interposed therebetween. The antennas 66 and 64 do not use wires such as coaxial cables for signal transmission. For example, a configuration in which a signal is transmitted by a waveguide such as a horn-type antenna is used. The receiving antenna 66 is installed with its opening facing the millimeter wave transmitter 22 or the reflector 51.
[0035]
FIG. 8B shows the rear surface of the receiving antenna 66. The receiving antenna 66 has a circular flange 66b surrounding the open end of the waveguide 66a. By bonding the flange 66b to the outer surface of the glass 61, the receiving antenna 66 can be attached to the glass 61.
[0036]
Similar to the receiving antenna 66, the transmitting antenna 64 for re-radiation provided indoors is an antenna of a kind to be fed without using a coaxial cable, for example, a horn-type antenna. The transmitting antenna 64 is attached to the glass 61 by a flange 64b. Reference numeral 67 denotes a storage section for the amplifier 63 and the battery power supply 65. The receiving antenna 66 and the transmitting antenna 64 are attached to the glass 61 such that the positions of the waveguides substantially coincide with each other. Since the glass 61 is often transparent, the antennas 66 and 64 can be mounted in alignment.
[0037]
The waveguide 66a and the flange 66b of the receiving antenna 66 and the waveguide and the flange 64b of the transmitting antenna 64 are made of metal. Normally, the two waveguides are fixedly connected using screws or the like, but in a glass-attached configuration, the waveguides of the two antennas are opposed to each other with the glass 61 interposed. As a result, radio wave reflection occurs between the flanges of the two antennas, which may cause distortion in the signal waveform.
[0038]
FIG. 9 shows several methods for preventing unnecessary reflection of radio waves from occurring at the connection portions of the reception antenna 66 and the transmission antenna 64 that face each other across the glass. Although the receiving antenna 66 will be described as an example, the same measures are taken for the transmitting antenna 64 as for the receiving antenna.
[0039]
In the example shown in FIG. 9A, the flange 66b that causes the reflection of radio waves is removed. FIG. 9B shows another example in which a non-metallic flange 66b 'is used as the flange to reduce the amount of reflection. FIG. 9C shows still another example in which a radio wave absorber 68 is attached to the flange 66b to suppress reflection.
[0040]
Next, another example of drawing a millimeter wave radio wave indoors will be described. FIG. 10A shows a glass 71 in which a V connector 70 that can be used in the millimeter wave band is embedded. The glass 71 is installed in a window facing, for example, a veranda of each subscriber. The configuration of the V connector 70 can have a form as shown in FIG. 10B. A configuration in which the female connectors 72a and 72b of the connector project from both sides of the glass 71, a configuration in which one side is a male 73a, and a configuration in which both sides are males 73a and 73b are possible. In the connector 70, the core wire of the coaxial line is embedded in the glass 71, and a signal can be drawn from the outside of the glass 71 to the inside (indoor).
[0041]
The existing glass is replaced with glass 71 in which the connector 70 shown in FIG. 10A is embedded, and the signal can be drawn indoors without making a hole in the wall. Further, since the antenna installed outdoors is connected by a coaxial cable, there is an advantage that the degree of freedom of the direction of the antenna is increased.
[0042]
In the above-described vertical wiring system, a configuration in which a radio wave from the transmitter 23 installed on the roof is reflected by the reflector 51 (see FIG. 4), a configuration in which the antenna is attached to the glass and drawn into each home (see FIG. 8), A method of drawing in through the connector 70 embedded in the glass 71 (see FIG. 10) can be adopted. Further, as shown in FIG. 11, a vertical wiring system in which a reflector 54 and a receiving antenna 66 are combined may be used.
[0043]
Millimeter wave radio waves are radiated from the millimeter wave transmitter 22 provided on the roof of the apartment house 20. On each floor, a reflector 54 for receiving a radio wave from the transmitter 22 is provided. The reflector 54 bends the traveling direction of the radio wave from the transmitter 22 at a substantially right angle, and directs it toward the receiving antenna 66 of each home. The signal received by the receiving antenna 66 is drawn indoors via a glass-attached configuration or a V-connector embedded in glass. Then, it is re-radiated indoors by the transmitting antenna. Further, although not shown, a reflector may be provided to change the radio wave reflected by the reflector 54 in a direction perpendicular to the window glass of each home.
[0044]
As described above, in the vertical wiring system, the variation in the reception level caused by the floor to be received is corrected. Also in the vertical wiring system shown in FIG. 11, the above-described variation in the reception level is corrected. In the vertical wiring system shown in FIG. 11, the mounting position of the receiving antenna installed in each home can be relatively freely selected.
[0045]
The present invention is not limited to the above-described embodiment of the present invention, and various modifications and applications are possible without departing from the gist of the present invention. For example, the millimeter wave transmitter may be installed not only on the roof but also on an upper floor such as the top floor.
[0046]
【The invention's effect】
ADVANTAGE OF THE INVENTION In the vertical wiring system by this invention, in an apartment house, a broadcast signal can be transmitted indoors of each resident, without installing a coaxial cable, an optical fiber, etc. newly outside a building. Therefore, it is possible to avoid an increase in cost due to the wiring work. Further, by combining an indoor wireless transmission system, indoor wiring work can be eliminated, and the cost can be further suppressed.
[0047]
In the antenna device according to the present invention, since the receiving antenna installed indoors or outdoors and the transmitting antenna installed indoors are combined, it is possible to draw the millimeter wave signal indoors with a compact configuration.
[Brief description of the drawings]
FIG. 1 is a schematic diagram for explaining a television video wireless transmission system in a home proposed above.
FIG. 2 is a schematic diagram illustrating an embodiment of a wireless transmission system according to the present invention.
FIG. 3 is a schematic diagram illustrating an extended configuration example of a wireless transmission system according to the present invention.
FIG. 4 is a schematic diagram illustrating an example of a configuration in which a signal from a millimeter-wave transmitter is pulled into the interior of each subscriber in a wireless transmission system according to the present invention.
FIG. 5 is a schematic diagram illustrating an example of directivity of a radio wave from a millimeter-wave transmitter.
FIG. 6 is a block diagram showing another example of a configuration for drawing a signal from a millimeter wave transmitter into each subscriber's room in the wireless transmission system according to the present invention.
FIG. 7 is a block diagram showing still another example of a configuration in which a signal from a millimeter wave transmitter is pulled into the interior of each subscriber in a wireless transmission system according to the present invention.
8 is a schematic diagram illustrating an example of an antenna device that realizes the configuration in FIG. 7;
9 is a schematic diagram for explaining a method of suppressing unnecessary reflection at a connection portion of the antenna device shown in FIG.
FIG. 10 is a schematic diagram for explaining a connector for drawing a signal from a millimeter wave transmitter into the interior of each subscriber in the wireless transmission system according to the present invention.
FIG. 11 is a schematic diagram showing another embodiment of the wireless transmission system according to the present invention.
[Explanation of symbols]
20: Apartment house, 22, 22A, 22B: Millimeter wave transmitter, 23, 23A, 23B, 23C: Receiver, 51: Reflector, 52: Reflector, 61, 71 ... glass, 62, 66 ... receiving antenna, 63 ... amplifier, 64 ... transmitting antenna, 70 ... connector

Claims (25)

A millimeter-wave transmitter is installed on the rooftop or upper floor of the building, and the above-mentioned millimeter-wave transmitter radiates a broadcast media signal downward as a millimeter-wave charged wave, and transmits the millimeter-wave charged wave to the resident of the building. A wireless transmission system characterized by wireless transmission. In claim 1,
Furthermore, a wireless transmission system that transmits a broadcast media signal as a millimeter-wave charged wave to another building nearby. In claim 1,
A wireless transmission system in which a traveling direction of a radio wave emitted from the millimeter wave transmitter is directed to a room of each resident by a reflector. In claim 3,
A wireless transmission system configured to correct a difference in reception level caused by a difference in distance between the millimeter wave transmitter and each of the plurality of reflectors. In claim 4,
A wireless transmission system in which a material of the reflector is a material having a lower reflectance on a floor close to the millimeter wave transmitter. In claim 4,
A wireless transmission system in which the reflection plate is installed at a place where the reception level is low on a floor close to the millimeter wave transmitter. In claim 1,
A wireless transmission system that receives a millimeter-wave charged wave from the transmitter by a receiving antenna attached to the indoor side of a plate that separates the outdoor and the indoor. In claim 7,
A wireless transmission system wherein a millimeter wave signal received by the receiving antenna is re-radiated indoors by a transmitting antenna. In claim 8,
A wireless transmission system in which the directivity of the transmission antenna is wide. In claim 1,
A wireless transmission system for receiving a millimeter-wave charged wave from the transmitter by a receiving antenna attached to an outdoor side of a plate separating an outdoor area and an indoor area. In claim 10,
A wireless transmission system in which a traveling direction of a millimeter-wave charged wave from the transmitter is directed to the receiving antenna by a reflector. In claim 10,
A wireless transmission system that transmits a millimeter wave signal received by the reception antenna to a transmission antenna provided indoors, and re-radiates the millimeter wave signal by the transmission antenna. In claim 12,
The end of the receiving antenna is attached to one surface of a plate that separates indoors and outdoors, and the end of the transmitting antenna is attached to the other surface of the plate at a location substantially coinciding with the end of the receiving antenna. Wireless transmission system. In claim 13,
A wireless transmission system wherein a connection between an end of the receiving antenna and an end of the transmitting antenna suppresses reflection of radio waves. In claim 12,
A core wire penetrates a board separating indoors and outdoors, two coaxial connectors project from both sides of the board, and the reception antenna and the transmission antenna are connected via the core wire and the two coaxial connectors. system. In claim 12,
A wireless transmission system in which the directivity of the transmission antenna is wide. In claim 12,
A wireless transmission system configured to correct a difference in reception level caused by a difference in distance between the millimeter wave transmitter and each of the plurality of reception antennas. In claim 17,
A wireless transmission system in which, on a floor close to the millimeter wave transmitter, the receiving antenna installation position is adjusted so as to be installed in a place where the reception level is low, and the reception level is kept low on the receiver side. In claim 17,
A wireless transmission system in which a material of a cover of the receiving antenna is made of a material having low transmittance on a floor close to the millimeter wave transmitter. A millimeter-wave transmitter is installed on the rooftop or upper floor of the building, and the above-mentioned millimeter-wave transmitter radiates a broadcast media signal downward as a millimeter-wave charged wave, and transmits the millimeter-wave charged wave to the resident of the building. A wireless transmission method characterized by transmitting wirelessly. In an antenna device that receives a millimeter-wave charged wave outdoors and re-radiates a received signal indoors,
The end of the receiving antenna is attached to one surface of a plate that separates the indoor and outdoor areas, and the end of the transmitting antenna is attached to the other surface of the plate at a location substantially coincident with the end of the receiving antenna. Antenna device made as above. In claim 21,
An antenna device in which an end of the receiving antenna and an end of the transmitting antenna attached to the plate have no flange. In claim 21,
An antenna device in which an end of the reception antenna and an end of the transmission antenna attached to the plate have a nonmetallic flange. In claim 21,
An end of the receiving antenna and an end of the transmitting antenna attached to the plate each have a flange, and have an electromagnetic wave absorber between each of the flanges and the plate. In an antenna device that receives a millimeter-wave charged wave outdoors and re-radiates a received signal indoors,
An antenna device in which a core wire penetrates a board separating indoors and outdoors, two coaxial connectors project from both sides of the board, and the reception antenna and the transmission antenna are connected via the core wire and the two coaxial connectors. .

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