JP2006222778A - Radio lan system and its antenna module - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inexpensive radio LAN system capable of being easily installed even outdoors and preventing communication quality from being deteriorated even when local circumstances are changed. <P>SOLUTION: A high frequency line 2 constituted of arranging patch antennas 5 each of which is constituted of sequentially laminating a dielectric layer consisting of dielectric materials and a radiation plate consisting of a conductive material and functioned as a radio base station is arranged on the ground along a plurality of passages and a conical radio wave reflector 6 whose top is oriented downward to reflect a radio wave radiated from each patch antenna 5 to peripheral directions is arranged on the upper position of the patch antenna 5. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a high-frequency microstrip line that propagates a high-frequency electromagnetic wave (hereinafter also referred to as electromagnetic wave or high-frequency) signal in a radio frequency band, for example, in a wireless LAN system that forms a wireless communication network.

  In recent years, with the development of advanced information technology, inside offices in buildings, on the premises such as factories and warehouses, in general houses and offices, and other arcades such as shopping streets other than indoors, The use of wireless LAN systems (intra-area wireless communication networks) that form wireless communication networks in certain areas, such as station platforms, airport terminals, large temporary structures such as tents, and event venues, is increasing. As such a wireless LAN system according to the conventional example, a wireless LAN system having a configuration described later is known.

Hereinafter, a first conventional example relating to a wireless LAN system will be described with reference to the attached drawings.
12 is a plan view of a high-frequency microstrip line (high-frequency transmission line) of the wireless LAN system according to Conventional Example 1, and FIG. 13 is a cross-sectional view taken along line BB of FIG.

  Reference numeral 51 shown in the figure is a thin plate-shaped high-frequency microstrip line having a length necessary for the wireless LAN system. As shown in FIG. 13, the high-frequency microstrip line 51 is flexible, and as shown in FIG. 13, a high-frequency microstrip line 51 includes a ground layer 52 made of a conductive material, a dielectric layer 53 made of a dielectric material, and a high-frequency made of a conductive material. The guide signal line 54 is laminated in the order of description. 12 and 13, the patch antenna 60 has a structure in which a dielectric 61 made of a dielectric material and a radiation plate 62 made of a conductor material are sequentially laminated. A plurality of patch antennas 60 are installed on the signal line 54 at a predetermined interval such as the interval L, and are electrically coupled to the signal line 54.

  The high-frequency microstrip line 51 of the wireless LAN system configured as described above is manufactured to be extremely thin, and is disposed on the indoor top. By the way, depending on the layout of the handset group of the wireless LAN system, high-frequency interference between adjacent patch antennas 60 may occur. Therefore, there are two types of patch antennas 60, a left-turn circular polarization antenna and a right-turn circular polarization antenna, and these antennas are alternately arranged to prevent interference (see, for example, Patent Document 1). .

  Conventional Example 2 relating to the wireless LAN system will be described with reference to FIG. 14 which is a block diagram showing the configuration of the wireless base station. This minimizes the interference between the wireless base stations of the wireless LAN system, and is changed to the optimum channel and cell settings when sudden external noise occurs. That is, the directional antenna of the radio base station 160 includes antenna units 161 to 164 that output radio signals, phase adjusters 165 to 168, and attenuators 169 and 16A to 16C. The RF interface 16D for outputting RF to the directional antenna is composed of an RF unit 16E and a BB unit 16F. The wired LAN interface 16J that exchanges data with the wired LAN 16K and the RF interface 16D are connected via the control unit 16G, and the control unit 16G stores location information, search information, and the like of the wireless base station. A memory 16H is connected. The position information 16I and the search information 16L are stored in the memory 16H.

  The electric field strength of another radio base station obtained by the directional antenna is converted into polar coordinate information based on the radio base station by the control unit 16G via the RF interface 16D, and is stored as position information 16I in the memory 16H. Stored. When obtaining the location information 16I via the wired LAN 16K, the control unit 16G receives a packet sent from another wireless base station from the wired LAN 16K via the wired LAN interface 16J, and uses this wireless base station as a reference. It is converted into polar coordinate information, merged with the information stored in the position information 16I of the memory 16H of this radio base station, and stored again as the position information 16I in the memory 16H.

The search information 16L is information indicating whether or not another wireless base station is searching for the vicinity, and packets sent from the other wireless base stations are transmitted from the wired LAN 16K to the wired LAN interface 16J and the control unit 16G. And stored as search information 16L in the memory 16H. In such a radio base station, an available channel and a communicable area are set based on the obtained other radio base station direction and distance. At this time, the communicable area is set by adjusting the power of the wireless output, adjusting the reception sensitivity, and adjusting the directivity of the directional antenna (see, for example, Patent Document 2).
JP 2004-165707 A JP 2004-282463 A

The microstrip line of the wireless LAN system according to the conventional example described in Patent Document 1 is extremely useful because the mobile communication can be performed anywhere in the connection area in an office or home. Conceivable. However, there are the following problems in using a wireless LAN in a production line, a raw material / stock yard, a transfer line, a port container yard, a distribution warehouse, and the like in a factory.
(1) There is no installation place for ceilings, pillars, steel towers, etc. for mounting a base station or a base unit (hereinafter referred to as AP) outdoors.
(2) Indoors, ceiling is high and maintenance after installation is difficult.
(3) There are large equipment, manufacturing equipment, products, containers for transportation, etc., and the outlook is bad.

In other words, when it is desired to use a wireless LAN in the above-described area, in order to solve the above-described problem, generally, APs are installed at a plurality of high places where the APs are scattered, and wireless communication is performed from the installation positions. It is common to send a signal. However, such a general method has the following problems.
(1) In order to improve the prospect, it is necessary to set up a high column or tower for installing the AP at a high place, so the construction cost becomes high. Moreover, it is likely to become an obstacle to movement of the transport vehicle or the like.
(2) If the line of sight cannot be improved, a large number of APs must be installed, which increases the required equipment cost.
(3) When many APs are installed, the number of channels that can be used is finite. Therefore, inter-channel interference is likely to occur, and communication quality (communication speed) may be reduced.
(4) Also, when a slave station exists between a plurality of APs, the radio propagation state changes due to a change in the surrounding environment, so that the frequency with which the AP connected to the slave station is switched increases. Accordingly, since communication becomes unstable, instability such as communication disconnection occurs.

  In the wireless LAN system according to the conventional example described in Patent Document 2, the frequency and electric field strength of the surrounding wireless base stations are obtained by using a highly directional antenna so that a plurality of wireless base stations do not interfere with each other. Position information. Then, from this position information, each communicable area and the use frequency are determined. Since the surrounding situation changes every moment, the communication area also changes. Therefore, since it is necessary to frequently perform optimization, there is a problem that effective communication quality (communication speed) decreases with the optimization processing.

  Therefore, an object of the present invention is to be easily installed even outdoors, and the communication quality (communication speed) does not decrease even if the surrounding situation changes, and the wireless LAN system and its antenna module are inexpensive. Is to provide.

  If the inventors arrange an antenna module used for a base station of a wireless LAN system on the ground along each of a plurality of passages, it is not necessary to stand high pillars and towers, and the surrounding situation changes. Even when the communication quality (communication speed) is not lowered, it is possible to provide an inexpensive wireless LAN system.

  Therefore, in order to solve the above problems, the wireless LAN system according to claim 1 of the present invention employs a wireless base station in which a dielectric layer made of a dielectric material and a radiation plate made of a conductive material are sequentially stacked. A high-frequency transmission line in which patch antennas are arranged at predetermined intervals is arranged on the ground along each of a plurality of passages, or buried underground, and from each patch antenna above the patch antenna, A radio wave reflecting mirror that reflects the radiated radio waves in the surrounding direction is provided.

  The wireless LAN system according to claim 2 of the present invention employs the wireless LAN system according to claim 1, wherein the high-frequency transmission line includes a dielectric layer made of a dielectric material and a conductor on a ground layer made of a conductor material. It is characterized in that it is one of a microstrip line, a coaxial cable, and a waveguide having a structure in which signal lines made of materials are sequentially laminated.

  The means adopted by the wireless LAN system according to claim 3 of the present invention is that, in the wireless LAN system according to any one of claims 1 and 2, the patch antenna has a left-turn circular bias that turns left. There are two types of wave antennas that radiate right-handed circularly polarized waves, and patch antennas that radiate left-handed circularly polarized waves and patch antennas that radiate right-handed circularly polarized waves are the high-frequency transmissions. It is characterized by being alternately arranged on each of the paths.

  The means adopted by the wireless LAN system according to claim 4 of the present invention is the wireless LAN system according to any one of claims 1 to 3, wherein the radio wave reflector is formed in a conical shape, The conical apex side is directed to the patch antenna side.

  The means adopted by the wireless LAN system according to claim 5 of the present invention is the wireless LAN system according to any one of claims 1 to 3, wherein the radio wave reflecting mirror has a sharp apex. The bus bar is formed in a curved substantially conical shape, and the apex side of the substantially conical shape is directed to the patch antenna side.

  The means adopted by the wireless LAN system according to claim 6 of the present invention is the wireless LAN system according to any one of claims 1 to 3, wherein the radio wave reflector is formed in a square cone shape. The apex side of the quadrangular cone is directed to the patch antenna side.

  The means adopted by the wireless LAN system according to claim 7 of the present invention is the wireless LAN system according to any one of claims 1 to 3, wherein the radio wave reflecting mirror has a sharp apex. The bus bar is formed in a substantially quadrangular cone shape that is curved, and the apex side of the substantially quadrangular cone shape is directed to the patch antenna side.

  The means employed by the antenna module according to claim 8 of the present invention is an antenna module used for a wireless base station of an outdoor wireless LAN system, and is disposed on the ground along each of a plurality of passages or underground. A patch antenna embedded with a dielectric layer made of a dielectric material and a radiation plate made of a conductive material, and a radio wave radiated from the patch antenna disposed in the upper direction. And a radio wave reflecting mirror that reflects the light.

  The antenna module according to claim 9 of the present invention employs the antenna module according to claim 8, wherein the patch antenna of the antenna module includes a dielectric layer made of a dielectric material and a conductor on a ground layer made of a conductor material. It is configured to take in a high frequency transmitted via any of a microstrip line, a coaxial cable, and a waveguide, which are configured by sequentially laminating signal lines made of materials. To do.

  The means adopted by the antenna module according to claim 10 of the present invention is the antenna module according to any one of claims 8 and 9, wherein the patch antenna of the antenna module is a left-turn circle that turns left. An antenna module having a patch antenna that irradiates a left-handed circularly polarized wave and a patch antenna that radiates a right-handed circularly polarized wave. The antenna module is provided alternately on the ground along each of the plurality of passages.

  The means adopted by the antenna module according to claim 11 of the present invention is the antenna module according to any one of claims 8 to 10, wherein the radio wave reflector is formed in a conical shape. The top of the shape is directed to the patch antenna side.

  The means employed by the antenna module according to claim 12 of the present invention is the antenna module according to any one of claims 8 to 10, wherein the radio wave reflector has a busbar so that the apex is sharp. It is formed in a curved substantially conical shape, and the apex side of the substantially conical shape is directed to the patch antenna side.

  The means adopted by the antenna module according to claim 13 of the present invention is the antenna module according to any one of claims 8 to 10, wherein the radio wave reflector is formed in a square cone shape. The apex side of the quadrangular cone is directed to the patch antenna side.

  The means adopted by the antenna module according to claim 14 of the present invention is the antenna module according to any one of claims 8 to 10, wherein the radio wave reflector has a busbar so that the apex is sharp. It is formed in a curved substantially quadrangular cone shape, and the apex side of the substantially square cone shape is directed to the patch antenna side.

  In the wireless LAN system according to claims 1 to 7 of the present invention and the antenna module according to claims 8 to 14 of the present invention, the patch antenna is disposed on the ground along each of the plurality of passages or buried underground. The radio wave radiated from the patch antenna is reflected by the radio wave reflecting mirror in the direction around the patch antenna.

Therefore, according to the wireless LAN system according to claims 1 to 7 of the present invention and the antenna module according to claims 8 to 14 of the present invention, the following effects can be obtained.
(1) Since the patch antenna is provided on the ground along the road or below the ground, it is not necessary to install a high pillar or tower in order to install the patch antenna which is a radio base station.
(2) By arranging a large number of high-frequency transmission lines and antenna modules including patch antennas and radio wave reflecting mirrors on the ground or by embedding a large number of them in the basement, there will be no influence on the line of sight.
(3) Since a communication area can be set, channel interference is unlikely to occur, and communication stability between a patch antenna, which is a radio base station, and a slave station is increased.

At the site of a large factory, an operator wants to obtain various operation information and equipment information in the factory. When connecting to a factory network via mobile, wireless communication is required.
However, large factories have high ceilings, and there are many manufacturing devices and machines. There is no place to install a radio base station. It becomes difficult. In a container yard of a port, a truck that transports containers receives containers from the center and transports containers. Therefore, communication is required between the center and the truck. However, in the container yard of the port, as in the case of the factory as described above, there are many containers, there is no place for installing a wireless base station, and the line of sight is blocked by the container, and wireless communication cannot be performed.

For example, in a factory or a container yard, as shown in FIG. 9 of a schematic perspective view thereof, an area S ₁ that needs to perform wireless communication and an area A ₀ that does not need to perform wireless communication over a wide area. Exists. However, the area A ₁ where wireless communication is necessary is generally a passage through which workers and trucks such as trucks can come and go. On the other hand, there are manufacturing facilities and containers in the area A ₀ where wireless communication is not required. Of course, there may be communication needs even in the area A ₀ where wireless communication is not required. In such a case, the wireless terminal may be moved to the communicable area.

  When a radio base station having a high height is set up with respect to the communicable area shown in FIG. 9, the propagation of radio waves from the radio base station depends on the state of manufacturing equipment and containers existing in the communication section to the radio terminal. Change. When the number of manufacturing facilities and containers is small, the communicable area Ac is widened as shown in FIG. 10 of the radio wave propagation state explanatory diagram when there are few manufacturing facilities and containers in the factory or container yard. On the other hand, when there are many manufacturing facilities and containers, the communicable area Ac becomes relatively narrow as shown in FIG. 11 of the radio wave propagation state explanatory diagram when there are many manufacturing facilities and containers in the factory or container yard. Therefore, since the communicable area Ac changes according to the number of manufacturing facilities and containers, it is difficult for the user to use. In addition, when a wireless base station having a higher height is provided in an attempt to increase the communicable area Ac, there is a problem that interference occurs in the same channel because the number of channels is limited.

  Therefore, the inventors can solve the above problem by arranging a high-frequency transmission path (including an antenna module) on the ground of the passage or underground in the factory yard or the passage of the container yard. It is what I thought. Hereinafter, a wireless LAN system according to Embodiment 1 of the present invention will be described with reference to the attached drawings. FIG. 1 is an explanatory diagram of an arrangement state of a high-frequency microstrip line (hereinafter referred to as a high-frequency line) that is a high-frequency transmission line of a wireless LAN system, FIG. 2 is a plan view of the high-frequency line, and FIG. It is AA sectional view. FIG. 4 is an explanatory side view of the antenna module provided on the high-frequency line, and FIG. 5 is a schematic perspective view of the antenna module provided on the high-frequency line.

  A high-frequency line 2 described later of the wireless LAN system 1 according to the first embodiment of the present invention is configured as shown in FIG. That is, the high-frequency line 2 is arranged on the ground along the factory yard or the container yard passage (in this embodiment, there are three rows, but the number of arrangement of the high-frequency transmission lines 2 can be changed as necessary. The high-frequency line 2 is protected by a protective means such as a metal pipe for waterproofing and prevention of breakage. These high-frequency lines 2 are all extended in the right direction in the figure from the wireless LAN base unit 3 provided on the left side in the figure.

  On the high-frequency line 2, antenna modules 4 serving as radio base stations are arranged at a predetermined interval, for example, L (see FIG. 2), and the inside of the frame indicated by a thin line is a communicable area Ac. ing. In this communicable area Ac, a wireless terminal (slave unit) (not shown) for receiving and communicating with the radio wave transmitted from the wireless LAN base unit 3 via the high-frequency line 2 and radiated from the antenna module 4 ) Is carried, for example, by an operator and installed in a truck. In the case of Form 1, as described above, the high-frequency line 2 is arranged on the ground along the road. However, if the antenna module 4 is exposed on the ground, the high-frequency line 2 is underground. It may be embedded in.

  The high-frequency line 2 of the wireless LAN system 1 is formed in a thin strip shape as shown in FIG. As shown in FIG. 3, the cross-sectional shape of the high-frequency line 2 includes a ground layer 2a made of a conductor material, a dielectric layer 2b made of a dielectric material, and a signal line 2c for high-frequency induction made of a conductor material in the order of description. The high frequency transmission line 2 is configured to be bent and deformed.

  As shown in FIGS. 2 and 3, the antenna module 4 includes a patch antenna 5 in which a dielectric plate 5a made of a dielectric material and a radiation plate 5b made of a conductive material are stacked in the order of description. The patch antennas 5 adjacent to each other are configured to radiate a left-turn circular polarization that turns left and a right-turn circular polarization that turns right. In this case, the signal line 2c may be embedded in the dielectric layer 2b and arranged in the longitudinal direction of the high-frequency line 2, and protruded or placed on the dielectric layer 2b, It may be arranged in the longitudinal direction.

  The ground layer 2a is made of metal such as copper, aluminum, tin, gold, nickel, or solder. The dielectric layer 2b is made of a resin dielectric material such as glass fiber, polytetrafluoroethylene (DuPont's trade name: Teflon), polyimide, polyethylene, polystyrene, polycarbonate, vinyl, or mylar. The signal line 2c is made of a fine wire or a thin plate-like highly conductive metal material. The thickness and width of the high-frequency line 2 made of such a material is preferably as small as possible.

  Therefore, the thickness of the ground layer 2a is set to 0.2 mm or less, the width is set to 10 to 50 mm, the thickness of the dielectric layer 2b is set to 0.1 to 2.0 mm, and the width is set to 10 to 50 mm. The thickness of the signal line 4 is set to 0.2 mm or less. In the case of the wireless LAN system 1 according to the first embodiment, the high frequency line 2 is used to transmit a high frequency from the wireless LAN base unit 3 as described above. However, the present invention is not limited to this, and for example, a coaxial cable or a waveguide having a well-known configuration can be used.

The antenna module 4 includes a radio wave reflecting mirror 6 having a configuration to be described later.
The radio wave reflecting mirror 6 is disposed above the patch antenna 5 and, as shown in FIG. 4, a support casing 7 made of, for example, plastic, polytetrafluoroethylene, acrylic, glass, or the like that transmits radio waves. Supported at the top. As shown in FIG. 5, the radio wave reflecting mirror 6 is formed in an inverted conical shape with the top facing downward.
That is, the radio wave reflecting mirror 6 is configured to radiate along the ground surface by reflecting the radio wave radiated upward from the patch antenna 5 in the side direction of the support casing 7.

  Incidentally, in the case of the wireless LAN system 1 according to the first embodiment, as described above, the radio wave reflecting mirror 6 is configured in an inverted conical shape, but as shown in FIG. 6 of a schematic perspective view of the antenna module according to the second embodiment. In addition, a rotation body of a saturation curve in which the generating line is curved so that the top of the lower part is sharp, that is, a substantially inverted conical shape, that is, a so-called cinder cone shape can be formed. Moreover, as shown in FIG. 7 of the schematic perspective view of the antenna module according to the third aspect, the antenna module can be formed in an inverted quadrangular pyramid shape with the top portion facing downward. Furthermore, as shown in FIG. 8 of the schematic perspective view of the antenna module according to the fourth aspect, the antenna module can be formed in a substantially inverted quadrangular pyramid shape in which the generating line is curved so that the top of the lower part is sharp.

  Hereinafter, an operation mode of the wireless LAN system 1 according to the embodiment of the present invention will be described. That is, the information signal transmitted from the wireless LAN base unit 3 is transmitted to the patch antenna 5 of the antenna module 4 through the high-frequency line 2 and radiated from the patch antenna 5 as a radio wave. In this case, the radio wave radiated from the patch antenna 5 is reflected by the radio wave reflecting mirror 6 and radiated along the ground, so that it is not radiated upward. Therefore, workers and drivers can easily communicate with each other on the roads of factories and container yards and on the driver's seats of trucks.

  According to the wireless LAN system 1 according to the first embodiment of the present invention, like the wireless LAN system according to the conventional example 1, the high pillars and towers for installing the wireless base station at a high place in order to improve the visibility. There is no need to stand up. Therefore, in addition to being advantageous with respect to the construction cost as compared to the conventional example 1, there is no obstacle to the movement of a transport vehicle such as a truck. In addition, according to the wireless LAN system 1 according to the first embodiment of the present invention, the high-frequency line 2 is arranged on the ground or buried along the road along the road, and there is no need to improve the line-of-sight, and many wireless bases Since there is no need to install a station, the required equipment cost is low.

  Further, as described above, it is not necessary to install a large number of radio base stations, and left-turn circular polarization and right-turn circular polarization are transmitted from the patch antenna 5 of the adjacent antenna module 4. . Therefore, inter-channel interference is unlikely to occur, and there is no fear that communication quality (communication speed) will decrease. Furthermore, even if a wireless terminal exists between a plurality of wireless base stations, it is unlikely that the line of sight is completely lost between the antenna module and the wireless terminal due to changes in the surrounding environment. The frequency of switching between stations does not increase. Therefore, since communication does not become unstable, instability such as communication disconnection does not occur.

  Further, in the wireless LAN system 1 according to the first embodiment of the present invention, as described above, the high-frequency line 2 is arranged on the ground or buried underground along the road, and communication is performed on the road. Regardless of changes in the surrounding situation due to changes in the number of production facilities and containers, the place of placement, etc., communication can be performed without any trouble. Therefore, unlike the wireless LAN system according to the conventional example 2, it is not necessary to optimize each communicable area and the use frequency according to the change in the communication area due to the surrounding situation that changes every moment. Therefore, there is no fear that the effective communication quality (communication speed) is lowered.

  Hereinafter, an example of a wireless LAN system according to an embodiment of the present invention will be described with reference to a wireless LAN system including an antenna module in which an inverted conical radio wave reflector is provided above a patch antenna connected to a high-frequency line. A case will be described as an example. In this embodiment of the wireless LAN system, a 2.4 GHz band wireless LAN signal is transmitted to an antenna module through a high-frequency line, radiated from a patch antenna, reflected by a radio wave reflector, and radiated outward. This is an example in the case where the radiation characteristics of the received radio waves are measured as received power.

The radio wave radiation characteristics in this wireless LAN system were measured using two types of radio wave reflectors having a bottom radius of 15 cm and a height of 7.5 cm and 15 cm. Then, the distance between the patch antenna and the top of the radio wave reflector is changed in three stages of 5 cm, 10 cm, and 15 cm, and the radio wave radiation characteristics are measured at a position 5 m away from the antenna module. Further, in order to confirm the superiority of the wireless LAN system according to the present invention, the radio wave radiation characteristics were measured at a position 5 m away from the patch antenna even when no radio wave reflector was provided. The measurement results of the radiation characteristics obtained by each of these measurements are as shown in Table 1 below.

According to Table 1 above, in the case of the wireless LAN system of the present invention, if the radio wave reflector is provided at an appropriate position, the received power is generally lower than that when the radio wave reflector is not provided. It has increased. For example, in the case of a radio wave reflector having a bottom radius of 15 cm and a height of 7.5 cm, the effect is greatest when the distance between the patch antenna and the top of the radio wave reflector is 10 cm, and a radio wave reflector is provided. Compared to the case where there is no received power, +9 dB larger received power is obtained.
Therefore, it is well understood that the wireless LAN system according to the present invention is extremely excellent because an extremely good result can be obtained by appropriately setting the distance between the patch antenna and the top of the radio wave reflector. .

  Note that the wireless LAN system according to the above aspect of the present invention is only a specific example, and is not limited to the configuration of the wireless LAN system according to the above aspect, and is within the scope not departing from the technical idea of the present invention. You can freely change the design.

FIG. 6 is an explanatory diagram of a state of arrangement of high-frequency lines in a wireless LAN system according to the first embodiment of the present invention. 1 is a plan view of a high-frequency line of a wireless LAN system according to Embodiment 1 of the present invention. It is the sectional view on the AA line of FIG. It is side surface explanatory drawing of the antenna module concerning the form 1 of this invention and provided in the high frequency track | line. 1 is a schematic perspective view of an antenna module provided on a high-frequency line according to Embodiment 1 of the present invention. FIG. 10 is a schematic perspective view of an antenna module according to Embodiment 2 of the present invention. FIG. 10 is a schematic perspective view of an antenna module according to Embodiment 3 of the present invention. FIG. 10 is a schematic perspective view of an antenna module according to Embodiment 4 of the present invention. It is a typical perspective view of a factory or a container yard. It is explanatory drawing of the propagation state of an electromagnetic wave when there are few manufacturing facilities and containers in a factory or a container yard. It is explanatory drawing of the propagation condition of an electromagnetic wave when there are many manufacturing facilities and containers in a factory or a container yard. It is a top view of the high frequency track | line of the wireless LAN system which concerns on the prior art example 1. FIG. It is the BB sectional view taken on the line of FIG. It is a block diagram which shows the structure of the wireless base station of the wireless LAN system which concerns on Embodiment 2 of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Wireless LAN system 2 ... High frequency line, 2a ... Ground layer, 2b ... Dielectric layer, 2c ... Signal line 3 ... Wireless LAN main unit 4 ... Antenna module 5 ... Patch antenna, 5a ... Dielectric layer, 5b ... Radiation plate 6 ... Radio wave reflector 7 ... Support casing

Claims (14)

  A high-frequency transmission path in which patch antennas serving as radio base stations in which a dielectric layer made of a dielectric material and a radiation plate made of a conductive material are sequentially stacked are arranged at predetermined intervals on the ground along each of the plurality of paths The wireless LAN system is characterized in that a radio wave reflecting mirror that is disposed in the basement or buried in the basement and reflects the radio wave radiated from the patch antenna in the surrounding direction is disposed above each of the patch antennas.   The high-frequency transmission line includes a microstrip line having a structure in which a dielectric layer made of a dielectric material and a signal line made of a conductive material are sequentially laminated on a ground layer made of a conductive material, a coaxial cable, and a waveguide The wireless LAN system according to claim 1, wherein the wireless LAN system is any one of the following.   There are two types of patch antennas that radiate a left-turn circular polarization that turns left and a right-turn circular polarization that turns right, a patch antenna that emits left-turn circular polarization and a right turn circular polarization. 3. The wireless LAN system according to claim 1, wherein patch antennas that radiate waves are alternately arranged in each of the high-frequency transmission lines. 4.   4. The wireless LAN according to claim 1, wherein the radio wave reflecting mirror is formed in a conical shape, and a vertex side of the conical shape is directed to the patch antenna side. 5. system.   The radio wave reflecting mirror is formed in a substantially conical shape having a generatrix bent so that the apex is sharp, and the apex side of the substantially conical shape is directed toward the patch antenna. The wireless LAN system according to any one of the above items.   4. The radio wave reflecting mirror is formed in a quadrangular cone shape, and the apex side of the quadrangular cone shape is directed to the patch antenna side. 5. Wireless LAN system.   4. The radio wave reflecting mirror is formed in a substantially quadrangular cone shape in which a generatrix is curved so that the apex is sharp, and the apex side of the substantially quadrangular cone is directed to the patch antenna side. The wireless LAN system according to any one of the above.   An antenna module used for a wireless base station of an outdoor wireless LAN system, which is disposed on the ground along each of a plurality of passages or buried underground, and is composed of a dielectric layer made of a dielectric material and a radiation made of a conductive material It is composed of a patch antenna in which plates are sequentially stacked, and a radio wave reflector that is disposed above the patch antenna and reflects radio waves radiated from the patch antenna in the surrounding direction. Antenna module.   A patch antenna of the antenna module includes a microstrip line in which a dielectric layer made of a dielectric material and a signal line made of a conductive material are sequentially stacked on a ground layer made of a conductive material, a coaxial cable, a waveguide, The antenna module according to claim 8, wherein the antenna module is configured to take in a high frequency transmitted through any one of the above.   The antenna antenna patch antenna includes two types of antennas that radiate left-handed circularly polarized waves that turn left and right-turned circularly polarized waves that turn right. 10. The module according to claim 8, wherein the module and an antenna module having a patch antenna that radiates right-handed circularly polarized waves are alternately arranged on the ground along each of the plurality of passages. The antenna module according to any one of the items.   11. The antenna module according to claim 8, wherein the radio wave reflecting mirror is formed in a conical shape, and a vertex side of the conical shape is directed to the patch antenna side. .   11. The radio wave reflecting mirror is formed in a substantially conical shape having a generatrix bent so that the apex is sharp, and the apex side of the substantially conical shape is directed toward the patch antenna. The antenna module according to any one of the items.   11. The radio wave reflecting mirror is formed in a quadrangular cone shape, and the apex side of the quadrangular cone shape is directed to the patch antenna side. 11. Antenna module. 11. The radio wave reflecting mirror is formed in a substantially quadrangular cone shape in which a bus is curved so that the apex is sharp, and the apex side of the approximately quadrangular cone is directed to the patch antenna side. The antenna module according to any one of the items.

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