JP7660755B2 - Wireless communication system - Google Patents

Description

The present invention relates to a wireless communication system that enables wireless communication inside and outside a mobile body, and in particular to a wireless communication system that enables wireless communication between the inside and outside of a mobile body such as an elevator car that is shielded from electromagnetic waves.

In the event of an earthquake, fire, lightning, mechanical failure of the elevator, or an emergency, passengers in an elevator, which is a moving object, press the intercom button or emergency button on the control panel inside the elevator car to contact an operator or a person who checks the emergency outside the elevator and take appropriate measures. However, in the event of a sudden emergency, it may be difficult to calmly find and press the intercom button or emergency button, or there may be no one to check the emergency. In addition, since communication is made through an operator outside the elevator, it may not be possible to operate it quickly. On the other hand, passengers in the elevator can respond more quickly and directly if they can contact people outside the elevator using a mobile wireless terminal such as a smartphone that they are familiar with and own. In addition, passengers in the elevator car may need to contact an external contact as soon as possible, not just when the elevator breaks down. In addition, passengers in the elevator car may access the Internet in an emergency to search for desired information, and it is desirable for a mobile wireless terminal such as a smartphone to be in a state where it can be used at all times.

However, as will be described later, "even if a passenger inside an elevator car tries to talk to an outside operator or person using a portable wireless terminal, the elevator car is surrounded on all four sides, above and below, by metal plates that block radio waves, and passengers inside the car cannot communicate directly with an outside operator or related parties using their portable wireless terminal. Portable wireless terminals such as smartphones are now a necessity for modern people, and there is a demand for them to be able to be used anytime, anywhere. However, because they cannot be used while inside a moving object such as an elevator car, related companies have received requests from various quarters for improvements and modifications.

The present invention makes it possible to achieve wireless communication inside and outside a moving vehicle such as an elevator car by applying vertical wireless communication technology such as a leaky waveguide-based waveguide LAN system and wireless backhaul network technology, as described below.

(Leaky coaxial cable LCX)
A "wireless communication system using leaky coaxial cable (LCX)" that efficiently supplies wireless radio waves inside a building using a transmission cable has been put to practical use. This wireless communication system using leaky coaxial cable includes at least one access point, a terminal section, and a transmission cable that is wired between the access point and the terminal section and transmits radio signals to communicate with a device as an antenna. The transmission cable is configured by connecting a leaky coaxial cable that leaks radio waves and a non-leaky coaxial section that does not leak radio waves via a heterogeneous cable connecting section. The leaky coaxial cable is one practical example of a leaky wave antenna required for configuring this communication system.

(Wireless backhaul network)
Wireless backhaul, which allows access points to communicate with each other wirelessly instead of by wired connection, has also been put to practical use. This technology has made wireless communication possible in places where installation was previously difficult. In addition, as long as a power source is available, this wireless communication does not require LAN construction for expansion, so access points can be freely added, enabling a stable wireless network over a wide area.

Patent document 1 discloses an in-elevator mobile phone relay system that allows users to call any other party from inside the elevator car using their mobile phone when a trapped-in fault occurs. The system includes an intercom control device that transmits an abnormality notification signal, a fault detector that transmits a trapped-in fault signal, a Bluetooth master station that transmits destination number information sent from the mobile phone via a control cable, and an elevator monitoring device that switches to a public line network, calls a call center or a destination via the public line network, and transmits and receives voice information. The system describes that when the elevator monitoring device receives a trapped-in fault signal and the transmission and reception of voice information between the intercom in the elevator car and the call center is completed, it connects the Bluetooth master station to the public line network, makes a call to the destination based on the received destination number information, and transmits and receives voice information between the destination and the mobile phone. Furthermore, paragraph 0009 of Patent Document 2 states that the problem the invention is trying to solve is, "...even if passengers inside the car try to contact the outside world using their mobile phones, elevator cars are generally surrounded by metal plates, which block high frequencies, so passengers inside the car are unable to freely communicate with the outside world using their mobile phones..."

JP 2003-204398 A

Below, the problems with wireless communication in conventional mobile objects will be explained using an "elevator car" as a concrete example. Elevator car wireless communication systems were capable of wireless communication across floors of a building. However, there was a problem with radio waves being significantly attenuated by wall materials on each floor of a building, making wireless communication difficult in spaces surrounded by walls on all sides. In particular, elevator shafts are covered with sturdy concrete blocks, which causes significant attenuation of radio waves. Furthermore, inside the elevator car, wireless communication is blocked by steel plates on the top and bottom of all four sides, which reflect radio waves from outside, making wireless communication extremely difficult.

Conventionally, emergency telephone lines in elevator cars were connected to the outside of the car by wired cables, which were then connected to the external public telephone network. As a result, these wired cables were designed to expand and contract when the elevator car went up and down, and there was a risk of the cables breaking due to repeated expansion and contraction, or coming loose from the connector, resulting in malfunction.

On the other hand, a communication method has also been proposed that employs directional antennas inside an elevator shaft. Antennas are installed at opposing upper and lower positions inside the elevator shaft, and wireless communication is carried out between the upper and lower floors. However, while this directional antenna is useful in a "line-of-sight environment," the inside of an elevator shaft is a closed space, and there is a risk that radio waves will be scattered inside the elevator shaft before a highly directional beam is formed, and the radio waves will not propagate in the vertical direction and will not reach the upper floors. In addition, when the elevator car moves between the upper and lower antennas as it goes up or down, the radio waves are reflected by the steel plates of the elevator car, preventing them from reaching the floors above.

In addition, because wireless communication to the inside of the elevator car was cut off, wireless communication to robots such as automated guided vehicles (AGVs) that transport construction materials and the like was also cut off inside the elevator car. If the inside and outside of the elevator car were connected via a communications network, information from cameras and sensors inside the vehicle could be clouded, making it possible to remotely control the robots, but because the essential wireless communication was cut off inside the vehicle, there was the problem that progress in clouding and robotization was hindered.

In addition, at construction sites, in order to transport construction materials and workers safely and efficiently using temporary elevators, workers stationed inside the elevator car communicate with workers on each floor by wired phone to coordinate the floors the elevator will stop at and the contents of the transport, but securing workers has become an issue due to the aging of workers and an increase in foreign workers due to labor shortages.

In addition, in hospitals, it is necessary to constantly monitor the vital signs of hospitalized patients, but while the patient is in the elevator car, wireless communication is blocked by the moving object, making it impossible to measure the vital signs of the patient. In hotels and other facilities, wireless communication inside the elevator car allows for quick and advanced service to customers, but there is a problem in that the quality of service cannot be ensured because wireless communication is blocked by the elevator car.

This problem of wireless communication between the inside and outside of an elevator car being blocked because the top and bottom four sides are covered with metal is not limited to elevator cars, but also occurs in other moving objects such as automobiles, buses, trucks, and subways. Furthermore, this problem is not limited to buildings where construction work has been completed, such as offices, factories, hospitals, and commercial facilities, but also occurs in temporary elevators installed at construction and civil engineering sites.

The purpose of this application is to solve this problem and provide a wireless communication system that allows easy wireless communication with the outside of a mobile body from inside the mobile body where radio waves are blocked, using a mobile wireless terminal such as a smartphone or tablet.

To achieve the above object, the wireless communication system of the present invention is characterized in that a mobile access point having an antenna connected to each other outside the mobile body and an antenna inside the mobile body is provided on a mobile body that is shielded from radio wave communication, a vertical wireless communication system is provided on the path of the mobile body, the antenna inside the mobile body wirelessly communicates with a portable wireless terminal device inside the mobile body, the antenna outside the mobile body is connected to an antenna section of the wireless communication system to form a wireless communication network, and the portable wireless terminal device is connected to a fixed access point via the wireless communication system and wireless communication network to communicate with a wireless communication device outside the mobile body.

With the above configuration, this wireless communication system enables communication inside and outside a mobile body where radio communication is blocked. If wireless communication can be freely performed inside and outside a mobile body where radio communication is blocked, passengers on the mobile body can communicate with the outside of the mobile body from inside the mobile body using their mobile wireless terminal devices such as smartphones and tablets. This allows immediate communication inside and outside the mobile body when an emergency occurs inside the mobile body, when a disaster such as a fire occurs in the mobile body, or when an earthquake occurs and users inside the mobile body are alerted. In addition, for example, when this wireless communication system is used at a construction site, transportation management using mobile wireless terminal devices, especially for workers and construction materials, becomes easier. In addition, for example, when this wireless communication system is used in a hospital, it becomes possible to constantly measure the vital signs of a patient even when the patient is inside the mobile body.

It is also preferable that the mobile access point is provided outside the mobile body, and an antenna is provided inside the mobile body facing the portable wireless terminal from the mobile access point, and wirelessly communicates with the portable wireless terminal carried by passengers inside the mobile body. This allows radio waves transmitted from the portable wireless terminal inside the mobile body to be easily transmitted and received by the antenna inside the mobile body provided at the mobile access point.

It is also preferable that an antenna outside the mobile body is installed facing the antenna unit of the wireless communication system from the mobile access point, and that they are positioned opposite each other to wirelessly communicate with the external wireless communication device of the mobile body. This allows transmission and reception from the mobile access point to the wireless communication device outside the mobile body.

In addition, it is preferable that the antenna inside the mobile body that communicates with the portable wireless terminal and the antenna outside the mobile body that communicates with the antenna unit of the wireless communication system are connected by a coaxial cable inside the mobile access point, and the coaxial cable communicates by penetrating a shield that blocks radio waves to the mobile body. In this way, the above-mentioned problem of wireless communication between the inside and outside being blocked because the mobile body is covered on all four sides with metal from above and below can be easily solved without impairing communication performance by connecting the antenna inside the mobile body and the antenna outside the mobile body with a coaxial cable inside the access point.

It is also preferable that the moving body is an elevator car installed in a building, the path along which the moving body moves is an elevator shaft along which the elevator car ascends and descends, and the moving access point is an elevator access point.

It is also preferable that the antenna of the elevator access point and the antenna section of the wireless communication system communicate via a wireless backhaul. This wireless backhaul network allows for the creation of a stable communication environment.

It is also preferable that multiple elevator access points are installed inside the elevator shaft and form a wireless communication network between them. This formed communication network can create a stable communication environment.

It is also preferable that both backhaul radio waves and wireless LAN radio waves are output to the antenna section of the wireless communication system. In this way, the waveguide of the waveguide LAN system can leak radio waves through the waveguide, and the leaked radio waves are output as both backhaul radio waves and wireless LAN radio waves, enabling stable wireless backhaul communication.

It is also preferable that the elevator access point forms a wireless communication network with an antenna unit in a line-of-sight environment of the line-of-sight wireless communication system. This allows the elevator access point to reliably communicate with an external wireless communication device in the elevator shaft via the antenna unit of the wireless communication system.

It is also preferable that the elevator access point installed in the elevator shaft be capable of communicating with the portable wireless terminals of passengers in the elevator hall on the floor on which it is installed. This allows priority to be given to calls with passengers in the elevator hall on the floor on which the elevator access point is installed, who require communication with the inside of the elevator car, in the event of an emergency.

In addition, it is preferable that the waveguide LAN system uses a metal pipe used on-site as the waveguide, attaching flanges to the ends of the metal pipe and joining them together with bolts. In this way, in the waveguide LAN system, which is one embodiment of a wireless communication system, a single pipe used for scaffolding at construction sites is used as the waveguide. This has the advantages of making it easy to procure the waveguide at the construction site, making it easy to assemble and disassemble this single pipe, and allowing it to be freely repurposed at other construction sites.

As described above, the wireless communication system according to the present invention can provide a wireless communication system that allows easy wireless communication with the outside of a mobile body from inside the mobile body where radio waves are blocked, using a mobile wireless terminal such as a smartphone or tablet.

1 is a cross-sectional view showing a schematic configuration of one embodiment of a wireless communication system according to the present invention. 2 is a detailed cross-sectional view showing a schematic configuration of a waveguide LAN system which is an embodiment of the wireless communication system of FIG. 1. 1 shows an outline of a waveguide LAN system, which is an embodiment of a wireless communication system, in a partial detailed view, and an outline of a radio wave leakage cable in an exploded detailed view. FIG. 2 is a block diagram showing a configuration of the wireless communication system of FIG. 1. FIG. 1 is an explanatory diagram showing a wireless backhaul communication network formed by an antenna outside the vehicle and an antenna unit installed inside the elevator shaft when the elevator is stopped at the Nth floor. 1 illustrates one embodiment of an antenna for an access point in a wireless backhaul communication network. FIG. 7 is an explanatory diagram of the configuration of a wireless backhaul communication network using the access point of FIG. 6 . FIG. 1 is an explanatory diagram relating to the configuration of a conventional wired communication network. FIG. 1 is an explanatory diagram showing an overview of a demonstration experiment conducted on-site for a wireless communication system according to the present invention. FIG. 1 is an explanatory diagram showing the results of a demonstration experiment conducted on the wireless communication system in the field.

(Wireless communication system)
The configuration of a wireless communication system 1 according to the present invention will be described in detail below with reference to the drawings. Fig. 1 shows a schematic configuration of one embodiment of the wireless communication system 1 according to the present invention in a cross-sectional view. Fig. 2 shows a detailed cross-sectional view of a schematic configuration of a waveguide LAN system 10 in the wireless communication system 1 of Fig. 1. In this specification, a case where a moving object 2 is an elevator car 2 going up and down a building will be described as an example of this wireless communication system 1.

Specifically, in this wireless communication system 1, the mobile object 2 is an elevator car 2 installed in a building, the track 5 along which the mobile object 2 moves is an elevator shaft 5 along which the elevator car 2 ascends and descends, and the mobile access point 8a is an elevator access point 8a.

This wireless communication system 1 is an invention in which a mobile access point 8a is provided with an antenna 6a outside the mobile body and an antenna 6b inside the mobile body that are connected to each other, and the travel path 5 of the mobile body 2 is provided with a waveguide LAN system 10 in which a waveguide 12 is connected to an antenna unit 11 of the mobile body 2, the antenna 6b inside the mobile body wirelessly communicates with a portable wireless terminal unit 3 inside the mobile body 2, the antenna 6a outside the mobile body forms a wireless network with the antenna units 11 of multiple mobile bodies 2, and the portable wireless terminal unit 3 is connected to the fixed access point 8b via the wireless communication network to communicate with an external wireless communication unit 14 of the mobile body 2.

In this wireless communication system 1, the smartphone 3 carried by a passenger or the like communicates with an antenna 6b in the mobile body provided at an elevator access point 8a provided outside the elevator car 2, which moves up or down in the elevator shaft 5 of a building (step 1). The antenna 6b in the mobile body is connected to an antenna 6a outside the mobile body provided at the elevator access point 8a via an access point coaxial cable 9a (see FIG. 2) (step 2). The antenna 6a outside the mobile body of the elevator access point 8a is connected to a plurality of antenna units 11 of a waveguide LAN system 10 installed in the elevator shaft 5 by a wireless backhaul communication network 7 (step 3). Then, in FIG. 1, the wireless communication system 1 communicates with an external wireless communication device 14 from the waveguide access point 8b connected to the lower end of the waveguide 12 (step 4). The access point provided on the moving elevator car 2 may be called "mobile access point 8a", and the access point connected to the multiple antenna units 11 fixed in the elevator shaft 5 may be called "fixed access point 8b". The mobile access point 8a may be specifically called "elevator access point 8a", and the fixed access point 8b may be specifically called "waveguide access point 8b". This makes it clear that the moving mobile access point 8a and the fixed access point 8b communicate with each other via the antenna unit 11. The position of the fixed access point 8b shown in FIG. 2 is not limited to the tip of the waveguide coaxial cable 9b at the lower end of the waveguide 12, but may be any position on the waveguide 12. The waveguide LAN system 10, which is a feature of the present invention, will be described in detail below.

(Waveguide LAN system)
FIG. 1 shows a cross-sectional view of the top floor, N+1 floor, N floor, N-1 floor, and basement floor around the elevator car 2 of a building. A hoist 41 for the elevator car 2, a control panel (motor) 42, a hoist support frame 43 for the elevator, and the like are installed in the elevator shaft 5. Note that a recent trend is that machine rooms are not provided except for large elevators. Furthermore, machine rooms are often not required even in building renovations. The elevator car 2 ascends and descends in the elevator shaft 5 by the up and down movement of a counterweight 48, and stops at the top floor, N+1 floor, N floor, N-1 floor, and basement floor. Landings 45 and elevator doors 47 are provided on the N+1, N, and N-1 floors, and passengers, construction materials, and the like enter and exit the elevator car 2. The waveguide LAN system 10 is a vertical wireless LAN system in a building such as a building. In this embodiment, the waveguide LAN system 10 is installed vertically from the top floor to the basement floor, which is the bottom floor, to a fixed access point 8b installed outside the elevator shaft 5, and performs wireless communication using a wireless communication system 1 installed in the elevator shaft 5, which is a vertical passageway.

(Elevator access point)
An elevator access point 8a is provided outside the elevator car 2. An antenna 6b inside the moving body is installed facing inward from this elevator access point 8a towards the portable wireless terminal 3 inside the elevator car 2, and wirelessly communicates with the portable wireless terminal 3 inside the elevator car 2. This allows radio waves transmitted from the portable wireless terminal 3 inside the elevator car 2 to be easily transmitted to and received from the antenna 6b inside the moving body provided at the elevator access point 8a.

An antenna 6a outside the vehicle is installed outside the elevator car 2, facing outward from the elevator access point 8a toward the antenna unit 11 of the waveguide LAN system 10, and can wirelessly communicate with the external wireless communication device 14 of the elevator car 2. This allows transmission and reception from the elevator access point 8a to a fixed access point 8b outside the elevator car 2.

As shown in FIG. 2, the inward-facing antenna 6b inside the moving body that communicates with the smartphone 3 inside the elevator car 2 and the outward-facing antenna 6a outside the moving body that communicates with the antenna part 11 of the waveguide 12 are connected by an access point coaxial cable 9a in the elevator access point 8a. This access point coaxial cable 9a communicates by penetrating the outer wall or ceiling of the shielded elevator car 2. In other words, the problem of wireless communication between the inside and outside being blocked because the top and bottom four sides of the elevator car 2 are covered with metal can be solved without impairing communication performance by providing both the antenna 6a outside the moving body and the antenna 6b inside the moving body at the elevator access point 8a and partially adopting the waveguide coaxial cable 9b as a part of the wireless cable. In addition, although this waveguide coaxial cable 9b is a wired cable 40, it is used for an extremely short distance, so it is not affected by the rise and fall of the elevator car 2 and does not slacken, so there is no risk of breakage, etc. The elevator doors 47 of the elevator car 2 open at each floor, but wireless communication between the antenna 6b inside the vehicle and the smartphone 3, or between the antenna 6a outside the vehicle and the antenna unit 11, does not go directly through the elevator doors 47.

As shown in Figures 1 and 2, multiple elevator access points 8a are installed inside the elevator shaft 5, and form a communication network between them to communicate wirelessly. This is because the inside of the elevator shaft 5 is a complex space, and wireless communication is not in a so-called "line-of-sight environment" due to the elevator car 2, equipment, lifting equipment, etc. Therefore, the elevator access points 8a moving inside the elevator shaft 5 are covered by a wireless backhaul communication network 7 so that the antenna unit 11 can reliably receive wireless radio waves. This formed wireless backhaul communication network 7 makes it possible to create a stable communication environment.

As shown in FIG. 2, the elevator access point 8a is installed outside the elevator car 2, and therefore can communicate wirelessly with the antenna unit 11 of the waveguide 12 in a line-of-sight environment from the elevator access point 8a. On the other hand, there is a risk that wireless communication between the elevator access point 8a and the antenna unit 11 of the waveguide 12 below the elevator car 2 may be blocked, particularly by the elevator car 2. In this way, by installing the elevator access point 8a outside the elevator car 2, communication can be reliably established between the elevator access point 8a and the antenna unit 11 in the elevator shaft 5.

(Waveguide LAN system and radio wave leakage cable)
FIG. 3 shows an outline of an embodiment of a waveguide LAN system 10 in a partial detailed view, and an outline of a leaky coaxial cable (LCX) 20 in an exploded detailed view. FIG. 3(a) shows a partial detailed view of the waveguide LAN system 10. In the waveguide LAN system 10, a waveguide 12 and an antenna unit 11 are connected. The antenna unit 11 is provided with a radio wave leakage unit 23 for emitting radio waves. The waveguide 12 is covered on the periphery with a metal pipe 17 that transmits radio waves inside and does not leak radio waves to the outside. The coaxial inner conductor 16 of the waveguide 12 is connected to a fixed access point 8b. FIG. 3(b) shows a leaky coaxial cable 20 in an exploded detailed view. In the leaky coaxial cable 20 of the antenna unit 11 shown in FIG. 3(b), the coaxial inner conductor 16 is covered on the periphery with a dielectric 18, and is further covered with an outer conductor 19. The outer conductor 19 is provided with a slit portion 15, which is a cut, and radio waves propagating inside leak from this slit portion 15. Therefore, the slit portion 15 serves as a radio wave leakage portion 23 of the waveguide 12. The cut of this slit portion 15 is made obliquely with respect to the axial direction of the leaky coaxial cable 20 so that radio waves can easily leak.

On the other hand, the waveguide 12 is called a wave guide 12. In this embodiment, the waveguide 12 uses a metal pipe 17, and a single pipe that is often used for scaffolding in on-site temporary construction is repurposed. That is, the metal pipe 17 is cut to a predetermined length, and a flange joint is attached to the end. Then, the metal pipes 17 are bolted together with the flange joint. The lower end of the waveguide 12 is connected to the waveguide access point 8b by the coaxial inner conductor 16. In this way, when a single pipe is used as the metal pipe 17, the waveguide 12 can be easily procured at the construction site. In addition, this single pipe has the advantage that it is easy to assemble and disassemble, and can be freely diverted to other construction sites.

(Wireless backhaul)
As described above, the antenna 6a outside the vehicle of the elevator access point 8a and the antenna units 11a to 11y of the waveguide LAN system 10 communicate wirelessly via the wireless backhaul communication network 7. This allows a more stable communication environment to be established between the access point antenna 31, the downstream side antenna 32, and the upstream side antenna 33. The antenna units 11a to 11y of the waveguide LAN system 10 are connected via a waveguide 12, and both backhaul radio waves and wireless LAN radio waves are output into the waveguide 12. This allows the waveguide 12 to leak radio waves from the slits 15, and the radio waves are output together as backhaul radio waves and wireless LAN radio waves, enabling stable wireless backhaul communication.

(Block configuration of wireless communication system)
Figure 4 is a block diagram showing the configuration of the wireless communication system 1 in Figure 1. Passengers riding in the elevator car 2 can wirelessly communicate with the external wireless communication device 14 of the elevator car 2 using their smartphones 3a to 3x in the event of an earthquake, a fire, an emergency patient, the elevator stopping due to a malfunction, etc. Alternatively, in the event of an emergency, they can directly contact a hospital, a fire station, a police station, an elevator management company, their home, their own company, etc.

The information transmitted from the smartphones 3a to 3x in the elevator car 2 is connected to an antenna 6b in the vehicle that is provided at an elevator access point 8a that is provided outside the elevator car 2. The information connected to the elevator access point 8a is connected to an antenna unit 11 in the elevator access point 8a via an access point coaxial cable 9a. The information is then transmitted from the antenna 6a outside the vehicle that is provided at the elevator access point 8a to the antenna units 11a to 11y of the waveguide LAN system 10 that is provided in the elevator shaft 5. The information transmitted to the antenna units 11a to 11y reaches the fixed access point 8b via the waveguides 12a to 12y and then reaches the external wireless communication device 14. In this waveguide LAN system 10, the antenna 6a outside the vehicle and the antenna units 11a to 11y on each floor form a wireless backhaul communication network 7.

(Wireless backhaul network)
FIG. 5 is an explanatory diagram showing a wireless backhaul communication network 7 that is configured by an antenna 6a outside the moving body and antenna units 11a to 11y installed in the elevator shaft 5 when the elevator is stopped at the Nth floor. The inside of the elevator shaft 5 is inherently a complex space, and it is assumed that wireless communication is not in a so-called "line-of-sight environment" due to the elevator car 2, equipment, lifting equipment, etc. Therefore, the wireless communication backhaul network 7 is configured so that the antenna units 11a to 11y can reliably receive wireless radio waves from the elevator access point 8a moving inside the elevator shaft 5. In addition, the elevator car 2 moving up and down inside the elevator shaft 5 is covered on all sides with iron plates, concrete, etc., which blocks radio waves. Therefore, as shown in FIG. 5, an antenna 6a outside the moving body is installed outside the elevator car and communicates with a fixed access point 8b below the elevator car 2.

For example, when the elevator car 2 shown in FIG. 5 is stopped on the Nth floor in the elevator shaft 5 (the elevator car 2 shown by the solid line in FIG. 5), wireless communication is performed with the antenna units 11b, 11a, 11c, etc., which are nearby on the Nth floor. At this time, the wireless radio waves are cut off at the antenna unit 11c due to being blocked by the elevator car 2, but the wireless radio waves reach the antenna units 11b and 11a, making the wireless backhaul communication network 7 possible. In this way, even if the elevator car 2 goes up and down in the elevator shaft 5, the wireless backhaul communication network 7 is covered by wireless communication due to the position of the elevator car 2. This allows the radio waves transmitted from the portable wireless terminal unit 3 in the elevator car 2 to be relayed to the waveguide access point 8b.

Figure 6 shows one embodiment of an access point antenna 31 constituting a wireless backhaul access point 8c of the wireless backhaul communication network 7. In conventional wireless communication technology, when elevator access points 8a are connected wirelessly, there is a problem that the throughput gradually decreases, and when communication passes through multiple locations, the wireless communication speed is not sufficient. The wireless backhaul antenna 6c for elevator access point 8a used in the present invention enables wireless communication at a maximum distance of several hundred meters.

Figure 7 is an explanatory diagram showing one embodiment of the configuration of the wireless backhaul communication network 7 using the wireless backhaul access point 8c in Figure 6. As described above, the wireless backhaul communication network 7 is a wireless communication method for dealing with the case where the inside of the elevator shaft 5 is a complex space and wireless communication is not in a so-called "line of sight environment" due to the elevator car 2, equipment, lifting equipment, etc. As shown in Figure 7, the access point antennas 31a to 31z each configure the wireless backhaul communication network 7 using the wireless backhaul antenna 6c and wirelessly communicate with each other. In this wireless backhaul communication network 7, wireless communication between the access point antenna 31b and the access point antenna 31c is blocked by a shield 34. At this time, wireless communication can be performed by detouring from the access point antenna 31b to the access point antenna 31c via the access point antenna 31d. In this way, the wireless backhaul communication network 7 allows the wireless backhaul antenna 6c of each antenna unit 11 to reliably receive wireless radio waves from the elevator access point 8a moving in the elevator shaft 5. This wireless backhaul communication network 7 makes it possible to create a stable communication environment.

Figure 8 shows an explanatory diagram of the configuration of a conventional wired communication network 7b. Each wired access point 8d is connected to a network switch 30 by a wired cable 40.

(Overview of the wireless communication system demonstration experiment)
FIG. 9 is an explanatory diagram showing an outline of a demonstration experiment conducted at a construction site for the wireless communication system 1 according to the present invention. Evaluation patterns A and B of the wireless communication system 1 were attached to an elevator car 2 installed in an elevator shaft 5 to measure the received power intensity (RSSI) of wireless LAN radio waves. FIG. 9(a) shows the case of evaluation pattern A of a conventional wireless communication system, and FIG. 9(b) shows the case of evaluation pattern B of the present wireless communication system 1. Evaluation pattern A is a demonstration experiment in which a passenger inside the elevator car 2 directly communicates with the outside of the elevator car 2 using a smartphone 3. That is, the received power intensity (RSSI) of wireless LAN radio waves at the elevator access point 8a was measured without installing an antenna 6a outside the moving body and an antenna 6b inside the moving body. Here, in the waveguide LAN system 10, the waveguide access points 8b on each floor are connected by waveguides 12a to 12d, and are connected to a fixed access point 8b at the lower end via a waveguide coaxial cable 9b.

Meanwhile, evaluation pattern B is an evaluation pattern of the wireless communication system 1 according to the present invention. That is, radio waves of the wireless backhaul communication network 7 are emitted from the waveguide LAN system 10 and connected to an antenna 6a outside the mobile body of a mobile access point 8a installed outside the elevator car 2. In addition, wireless LAN radio waves are emitted from an antenna 6b inside the mobile body installed inside the elevator car 2 to communicate with a smartphone 3 inside the elevator car 2. Here, in the waveguide LAN system 10 of evaluation pattern B, similar to the case of evaluation pattern A, the waveguide access points 8b on each floor are connected by waveguides 12a to 12d, and are connected to a fixed access point 8b at the lower end via a waveguide coaxial cable 9b.

(Results of demonstration experiment of wireless communication system)
FIG. 10 is an explanatory diagram showing the evaluation results of the demonstration experiment carried out at a construction site for the wireless communication system 1 according to the present invention. The unit of the evaluation results is dBm. FIG. 10 shows the received power intensity (RSSI) of the wireless LAN radio wave received by the evaluation terminal (PC) at the elevator stops on the first to seventh floors in a table for evaluation pattern A and evaluation pattern B. If this received power intensity (RSSI) falls below -75 dBm, high-volume communication such as video is interrupted, but in pattern A, it was below -75 dBm on all floors except the first floor. On the other hand, in evaluation pattern B, stable evaluation results were obtained on each floor, and the wireless communication system 1 according to the present invention was feasible, proving the usefulness of this wireless communication system 1.

The configuration, shape, size, and layout relationship described in the above embodiment of the wireless communication system 1 are merely shown in a schematic manner to enable the present invention to be understood and implemented. Therefore, the present invention is not limited to the described embodiment, and can be modified in various forms without departing from the scope of the technical ideas set forth in the claims.

1 wireless communication system, 2 mobile body or elevator car, 3, 3a to 3x portable wireless terminal or smartphone, 5 running path or elevator shaft, 6a antenna outside mobile body, 6b antenna inside mobile body, 6c wireless backhaul antenna, 7 wireless backhaul communication network, 7b wired communication network, 8a mobile access point or elevator access point, 8b fixed access point or waveguide (waveguide) access point, 8c wireless backhaul access point, 8d wired access point, 9a access point coaxial cable, 9b waveguide coaxial cable, 10 waveguide LAN system, 11, 11a to 11y antenna section, 12, 12a to 12y waveguide or waveguide, 14 external wireless communication device, 15 slit section, 16 coaxial inner conductor, 17 metal pipe, 18 dielectric, 19 outer conductor, 20 leaky coaxial cable, 21 Covering material, 22 socket, 23 (waveguide antenna) radio wave leakage part, 30 network switch, 31, 31a to 31z access point antenna, 32, 32a to 32z down stream side antenna, 33, 33a to 33z up stream side antenna, 34 shield, 40 wired cable, 41 hoist, 42 control panel (motor), 43 hoist support stand, 44 air conditioner, 45 landing, 47 elevator door, 48 counterweight.

Claims (6)

an elevator access point provided outside an elevator car, which is a moving body shielded from radio wave communication, and connected to a power source;
a waveguide LAN system installed inside an elevator shaft through which the elevator car ascends and descends;
A wireless communication system comprising:
The elevator access point includes:
An antenna within the moving body provided inside the elevator car;
an antenna outside the vehicle that is provided outside the elevator car and is communicatively connected to an antenna inside the vehicle;
The waveguide LAN system comprises:
A plurality of antenna units capable of wireless communication with antennas outside the moving body;
A waveguide including a metal pipe connected to each of the plurality of antenna units and transmitting radio waves.
Wireless communication system. The wireless communication system according to claim 1, wherein each of the plurality of antenna units is disposed between a plurality of elevator doors spaced apart in the height direction on the side wall of the elevator shaft. The wireless communication system according to claim 2, wherein each of the plurality of antenna units is arranged to face an antenna outside the moving body without passing through the elevator car when the elevator car stops in front of any one of the plurality of elevator doors. The wireless communication system according to claim 2 or 3, wherein each of the plurality of antenna units is disposed so as to face a wall directly above the plurality of elevator doors. A wireless communication system according to any one of claims 1 to 4, wherein one end of the waveguide LAN system is connected to a fixed access point provided outside the elevator shaft and capable of communicating with an external wireless communication device. The wireless communication system according to any one of claims 1 to 5, wherein the metal pipe is a single-tube pipe.

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