Wireless power - free relay device and wireless power - free relay system

Abstract

To simply set up a parasitic wireless relay device in an area where communication is impossible.SOLUTION: A parasitic wireless relay device 110 includes a first antenna 111a, a second antenna 111b, a signal transmission path 113, and a placement unit 114. The first antenna 111a is a portable antenna disposed in a first area where a mobile terminal device 120 can communicate. The second antenna 111b is a portable antenna disposed in a second area where the mobile terminal device 120 cannot communicate. The signal transmission path 113 connects the first antenna 111a and the second antenna 111b. The placement unit 114 is placed close to the second antenna 111b and allows the mobile terminal device 120 to be placed.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a power - free wireless relay device , and a wireless relay system without power supply and pertains thereto.

Background Art

[0002] In recent years, in urban areas and the like, a large number of sewer pipes have been installed underground. It is possible to enter the sewer from a manhole. Workers enter the sewer from the manhole and regularly conduct inspection work, repair work, etc. Here, since there is no constant human presence in the sewer, wireless equipment such as a wireless base station is not installed. Therefore, in the sewer, portable terminal devices such as mobile phones and smartphones cannot be used as communication means. Therefore, at present, an intercom is prepared as a communication means to communicate between underground workers and above - ground workers, or underground workers move to an area where radio waves can reach (near the ground) to make a call.

[0003] As a related technology, in a power - free wireless relay device that relays wireless communication between a base station and a user device, there is known one having a spherical radio wave reflection part that reflects radio waves used for wireless communication, a balloon arranged in the air, and a balloon support part that moors and supports the balloon (see Patent Document 1 below).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, in the prior art, there has been a problem that it is not possible to easily install a power - free wireless relay device in an area where communication is impossible.

[0006] The present invention has been made to solve the above problems, and an object thereof is to easily install a wireless power - free relay device in an area where communication is impossible.

Means for Solving the Problems

[0007] In order to solve the above - described problems, a wireless power - free relay device according to an aspect of the present invention includes a portable first antenna disposed in a first area where a portable terminal device can communicate, a portable second antenna disposed in a second area where the portable terminal device cannot communicate, a signal transmission path connecting the first antenna and the second antenna, and a mounting portion disposed in proximity to the second antenna for mounting the portable terminal device. , the first antenna and the second antenna are broadband and omnidirectional antennas capable of communicating with the mobile terminal device It is a wireless power - free relay device characterized by the above.

[0010] In the above configuration, the mounting portion may be configured to be able to mount the portable terminal device in a manner corresponding to the shape of the second antenna. multiple units It may be possible to mount.

[0012] In order to solve the above problems, a wireless relay system without power supply according to an aspect of the present invention is a wireless relay system without power supply including the wireless relay device without power supply described in any of the above and the mobile terminal device, The portable terminal device issues a warning regarding danger based on information on the current location, information on the rainfall in the vicinity, and information indicating the risk of water inflow set for each sewer, and notifies that a communication error has occurred when a communication error occurs. which is characterized by Wireless power - free relay a system

Effects of the Invention

[0014] According to the present invention, it is possible to easily install a wireless power - free relay device in an area where communication is impossible.

Brief Description of the Drawings

[0015]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Embodiments for Carrying Out the Invention

[0016] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0017] (Overview of this Embodiment) FIG. 1 is an explanatory diagram showing an example of the overview of this embodiment. As shown in FIG. 1, the area 100 includes a communicable area 101 and an out-of-service area 102. In the communicable area 101, wireless base stations 103 are arranged everywhere, and it is an area where the mobile terminal device 120 can communicate. The communicable area 101 is, for example, a ground area. The out-of-service area 102 is an area where communication of the mobile terminal device 120 is impossible. The out-of-service area 102 is, for example, an underground area, specifically, inside a sewer.

[0018] The work staff St performs inspection work and repair work on the sewer. In the illustration, the work staff St includes a ground work staff St1 who works on the ground and an underground work staff St2 who works underground. The underground work staff St2 enters the sewer from the ground along the steps 161 of the manhole 160.

[0019] Here, in places where people do not constantly exist, such as sewers (out-of-service area 102), wireless facilities such as wireless base stations 103 are not installed. For this reason, in the out-of-service area 102, a mobile terminal device 120 such as a mobile phone or a smartphone cannot be used. Therefore, in this embodiment, in the out-of-service area 102, the free-power wireless relay device 110 can be easily installed. Hereinafter, the free-power wireless relay device 110 according to this embodiment will be described in detail.

[0020] The free power wireless relay device 110 includes a first antenna 111a, a second antenna 111b, a signal transmission path 113, and a mounting portion 114. Both the first antenna 111a and the second antenna 111b are portable antennas, and the same ones are used. The first antenna 111a is arranged in the communicable area 101. The second antenna 111b is arranged in the out-of-service area 102.

[0021] The signal transmission path 113 is a signal transmission path that connects the first antenna 111a and the second antenna 111b. The mounting portion 114 is a jig that is arranged close to the second antenna 111b and mounts the portable terminal device 120. The portable terminal device 120 is a device capable of two-way wireless communication, that is, a device having transmission and reception functions. Specifically, the portable terminal device 120 is, for example, a smartphone. However, the portable terminal device 120 is not limited to a smartphone and includes mobile phones, tablet terminals, and the like.

[0022] (Appearance of the first antenna 111a and the second antenna 111b) FIG. 2 is an explanatory diagram showing an appearance example of the first antenna 111a and the second antenna 111b. The antenna 111 (the first antenna 111a and the second antenna 111b) is a broadband antenna. Specifically, the antenna 111 corresponds to, for example, frequencies from 700 MHz to 6 GHz.

[0023] Here, the reason for using a broadband antenna for the antenna 111 will be explained. For example, in normal wireless communication used by police, fire departments, and flood control, radio waves of a specific frequency are used. Therefore, the antenna to be used is manufactured to operate efficiently at a specific frequency. For example, in fire department wireless communication used at a fire scene, when communication between the fire scene and the headquarters is difficult, a command post equipped with a wireless communication base station function is set up at a communicable location, and another wireless device provided under its jurisdiction is used for relaying and communication. That is, it is possible for firefighters and the like to create a communicable situation at the scene by themselves.

[0024] In the wireless communication of the other party's mobile terminal device 120, an environment where communication is possible at any time and anywhere is required. In the wireless communication of the mobile terminal device 120, when communication is difficult, it is not allowed to install a wireless communication base station (relay device) by oneself like fire department wireless communication to create a situation where the user can communicate by oneself. This is because the users of the mobile terminal device 120 are ordinary people and not qualified wireless workers. From the above, in the radio waves of mobile phones, multi-frequencies are used as a means to maintain a good communication state, and a technology for using a good frequency band at that time has been put into practical use. Currently, in 4G (4th Generation), which is the mainstream in mobile phones and smartphones, 700 MHz to 3500 MHz is used.

[0025] Therefore, in performing free-power wireless relaying according to the present embodiment, in order to efficiently operate the mobile terminal device 120 such as a mobile phone and a smartphone, a broadband antenna corresponding to these frequency bands is used. Since the coaxial cable used as the signal transmission line 113 is essentially a broadband transmission line, it corresponds to these frequency bands.

[0026] The antenna 111 is an omnidirectional antenna. General-purpose products can be applied to the antenna 111. The antenna 111 shown in FIG. 2 is, for example, a discone antenna. Here, the discone antenna is composed of a conductor such as a copper plate. The discone antenna has a structure with a hole in the middle within a range where harmful losses can be ignored at the wavelength used for the purpose of weight reduction and simplification. Also, from the perspective of wave engineering, phenomena such as reflection, refraction, and diffraction of radio waves function effectively in members that are sufficiently larger or smaller than the wavelength to be used. In the discone antenna, the limit value on the short-wavelength side is determined by the number of elements 201a and 201b, and the limit value on the long-wavelength side is determined by the lengths of the elements 201a and 201b. For this reason, in the discone antenna, in the short-wavelength region such as the microwave band, it is manufactured with a one-piece structure such as a copper plate.

[0027] In FIG. 2, the antenna 111 includes, for example, about 18 upper elements 201a arranged at the upper part and about 16 lower elements 201b arranged at the lower part. The length of each cone element is about 10 cm. Since the antenna 111 is a finished product, that is, it does not assemble the elements 201 on-site, it can be installed immediately. Also, the size of the antenna 111 is about 8 cm in the width direction at the upper part, about 13 cm in the width direction at the lower part, and about 23 cm in the height direction. That is, the antenna 111 is compact and can be easily carried by the work staff St. Further, the antenna 111 is attached to the stand 210 via the attachment part 211 and is maintained at a predetermined height.

[0028] Note that the antenna 111 is not limited to a discone antenna, and for example, an LP (log-periodic) antenna, a self-complementary antenna, etc. can also be used. Note that the LP antenna has directivity. When communication is performed with a specific radio base station 103 using the LP antenna, on the communication carrier side, control is executed to enable communication in response to such a communication request.

[0029] (Regarding the signal transmission line 113) Next, the signal transmission line 113 will be described. In the present embodiment, for example, a high-frequency coaxial cable is used for the signal transmission line 113. The length of the signal transmission line 113 is, for example, about 15 to 20 m and at most about 30 m. That is, in the present embodiment, the distance between the first antenna 111a and the second antenna 111b is about 15 to 20 m and at most about 30 m. For the high-frequency coaxial cable, one with low loss and a small standing wave ratio over a wide band is used. Further, for the high-frequency coaxial cable, one with excellent flexibility and good shielding characteristics is used. Note that the signal transmission line 113 is not limited to a high-frequency coaxial cable, and for example, a feeder line (specifically, a ribbon feeder) can also be used.

[0030] (Appearance of the mounting part 114) FIG. 3 is an explanatory diagram showing an external appearance example of the mounting portion 114. In FIG. 3, the mounting portion 114 is arranged to cover the upper element 201a and the lower element 201b of the second antenna 111b. The mounting portion 114 includes an inclined portion 301, a top plate portion 302, and a mounting table 303. The mobile terminal device 120 is supported by the inclined portion 301 on the back side of the mobile terminal device 120 and placed on the mounting table 303.

[0031] The mounting portion 114 is made of a resin member. The mounting portion 114 may be a material that allows radio waves to pass through, that is, excluding materials that do not allow radio waves to pass through (for example, made of metal). The mounting portion 114 can mount the mobile terminal device 120 in a manner corresponding to the shape of the second antenna 111b. Specifically, when the second antenna 111b is a discone antenna, the mounting portion 114 can mount a plurality of mobile terminal devices 120 radially according to the shape of the discone antenna. Also, the closer the distance between the mobile terminal device 120 and the second antenna 111b (a part of the element 201), the better, and it is preferably within 3 cm. Note that the mobile terminal device 120 is not limited to being placed on the mounting table 303, and may be placed horizontally (planarly) on the top plate portion 302. Note that it is also possible to use a commercially available bucket for the mounting portion 114.

[0032] When the second antenna 111b is, for example, an LP antenna, the mounting portion 114 may mount a plurality of mobile terminal devices 120 horizontally (planarly) according to the shape of the LP antenna. In the case of an LP antenna, since the mounting portion 114 can secure a large mounting area, a plurality of mobile terminal devices 120 can be efficiently mounted.

[0033] (Regarding the mobile terminal device 120) When the mobile terminal device 120 is placed on the placement unit 114, it can communicate via the second antenna 111b. Therefore, when the mobile terminal device 120 is placed on the placement unit 114, it can connect to the Internet to display various information or make calls. When making a call, if the mobile terminal device 120 of the underground worker St2 is picked up and put to the ear, the mobile terminal device 120 will move away from the second antenna 111b and the communication will be disconnected. Therefore, when making a call, a headset may be connected to the mobile terminal device 120 and the call may be made via the headset.

[0034] (Hardware Configuration of Mobile Terminal Device 120) FIG. 4 is an explanatory diagram showing an example of the hardware configuration of the mobile terminal device 120. In FIG. 4, the mobile terminal device 120 includes a CPU (Central Processing Unit) 401, a ROM (Read Only Memory) 402, a RAM (Random Access Memory) 403, a memory 404, a communication interface (communication I / F) 405, an operation unit 406, a camera 407, a microphone 408, a display 409, a speaker 410, and a GPS (Global Positioning System) unit 411. Each unit is connected by a bus 420.

[0035] The CPU 401 controls the entire mobile terminal device 120. The ROM 402 records various programs. The RAM 403 is used as a work area for the CPU 401. That is, the CPU 401 controls the entire mobile terminal device 120 by executing various programs recorded in the ROM 402 and the memory 404 while using the RAM 403 as a work area.

[0036] Memory 404 stores various data. For example, flash memory is used as the memory. Memory 404 stores various programs such as a free-of-charge wireless relay application (application program). Further, memory 404 stores the sewer risk information 500 (see FIG. 5). The communication interface 405 is connected to a network via the first antenna 111a, the second antenna 111b, and the signal transmission path 113, and is connected to other devices such as an external server via the network. Communication networks that function as a network include the Internet and mobile phone networks.

[0037] The operation unit 406 is a touch panel that displays a plurality of touch keys for inputting characters, numerical values, various instructions, etc., or hard keys. The camera 407 images a subject. For example, a CCD (Charge-Coupled Device) camera can be used as the camera 407. The microphone 408 inputs the voice of the operator. The display 409 displays icons, cursors, menus, windows, characters, images, codes, etc.

[0038] The speaker 410 outputs sounds including voices. The GPS unit 411 receives radio waves from GPS satellites and outputs information indicating the current position of the portable terminal device 120. Further, the portable terminal device 120 includes various sensors (not shown) such as a gyro sensor and an acceleration sensor, and has a function of detecting various states of the portable terminal device 120 (for example, the inclination of the portable terminal device 120).

[0039] (An example of sewer risk information) FIG. 5 is an explanatory diagram showing an example of the sewer risk information 500 stored in the memory 404 of the mobile terminal device 120. The risk information 500 includes items of sewer No., location information, and risk level. The sewer No. is identification information assigned to each sewer and capable of uniquely identifying the sewer. The location information indicates the location where the sewer passes, for example, the range from a certain point to a certain point.

[0040] The risk level indicates, for example, the possibility (risk) of a water jet occurring when it rains. For example, a risk level of "3" indicates the most dangerous situation, that is, it is easy for a water jet to occur. A risk level of "2" indicates a slightly dangerous situation, that is, a water jet may occur depending on the amount of rainfall. Also, a risk level of "1" indicates a relatively safe situation, that is, it is difficult for a water jet to occur.

[0041] Note that the risk level is divided into three levels, but it is not limited to this, and it may also be divided into two levels. For example, when the risk level is divided into two levels, a risk level of "2" may indicate that it is dangerous (operation is prohibited) if even a single drop of rain falls in the vicinity, and a risk level of "1" may indicate danger depending on the rain situation in the vicinity. Also, the risk level may be four levels or more.

[0042] (Processing performed by the mobile terminal device 120) FIG. 6 is a flowchart showing an example of the wireless power-free relay processing performed by the mobile terminal device 120. As a premise for the processing in FIG. 6, it is assumed that the mobile terminal device 120 is placed on the placement unit 114. In FIG. 6, the mobile terminal device 120 determines whether it is the start of wireless power-free relay (step S601). The determination of whether it is the start of wireless power-free relay is, for example, the determination of whether the wireless power-free relay application has been started. The mobile terminal device 120 waits until the start of wireless power-free relay (step S601: NO), and when the start of wireless power-free relay occurs (step S601: YES), it determines whether the radio wave state is good (step S602).

[0043] In the determination of whether the radio wave state shown in step S602 is good, the mobile terminal device 120 determines that it is good if it receives data (for example, weather information) at intervals of a predetermined time, and determines that it is bad if it does not receive data at intervals of a predetermined time. Further, as an example of the case where a bad radio wave state occurs, for example, the distance between the mobile terminal device 120 and the second antenna 111b, an abnormality of the first antenna 111a such as the first antenna 111a falling down, and a connection failure of the signal transmission path 113 can be cited.

[0044] When the radio wave state is good (step S602: YES), the mobile terminal device 120 proceeds to step S605. When the radio wave state is not good (step S602: NO), the mobile terminal device 120 notifies a communication error indicating that the radio wave state is not good (step S603). The error is, for example, an error indicating that the mobile terminal device 120 should be brought closer to the second antenna 111b, an error indicating that there may be an abnormality in the first antenna 111a, or an error indicating a connection failure of the signal transmission path 113. Since the underground worker St2 is working, the mobile terminal device 120 may output an error notification sound in the communication error. Thereby, when a communication error occurs, it is possible to immediately notify the underground worker St2 who is working of a poor radio wave.

[0045] If the communication error is not resolved (step S604: NO), the mobile terminal device 120 returns to step S603 and continues to notify the error. On the other hand, when the communication error is resolved (step S604: YES), the mobile terminal device 120 acquires weather information around the current location (step S605). The weather information can be obtained from the Internet, for example. Further, when obtaining the weather information, the mobile terminal device 120 acquires the location information of the current location using the GPS unit 411 and obtains the weather information around the current location. Next, the mobile terminal device 120 determines whether there is rainfall within a predetermined range around (step S606).

[0046] When there is no rainfall within a predetermined range in the vicinity (step S606: NO), the mobile terminal device 120 proceeds to step S608. When there is rainfall within the predetermined range in the vicinity (step S606: YES), the mobile terminal device 120 issues a warning according to the risk level of the sewer indicated by the current location (step S607). For example, the warning in step S607 is a warning to evacuate immediately if the risk level is "3", a warning that although it is raining in the vicinity, there is no need to evacuate at the current time if the risk level is "2", and a warning indicating that although it is raining in the vicinity, the current location is not dangerous if the risk level is "1". Since the underground worker St2 is at work, the mobile terminal device 120 may output an alarm sound when the risk level is "3". Also, in the case of other risk levels, the mobile terminal device 120 may refrain from outputting an alarm sound.

[0047] The mobile terminal device 120 determines whether the power-free wireless relay has ended (step S608). The determination of whether the power-free wireless relay has ended is, for example, the determination of whether the power-free wireless relay application has ended. When the power-free wireless relay has not ended (step S608: NO), the mobile terminal device 120 returns to step S602. When the power-free wireless relay has ended (step S608: YES), the mobile terminal device 120 ends the series of processes.

[0048] As described above, the power - free wireless relay device 110 according to this embodiment connects a portable first antenna 111a arranged in the communicable area 101 and a portable second antenna 111b arranged in the out - of - service area 102 through a signal transmission path 113, and is provided with a mounting portion 114 which is arranged close to the second antenna 111b and on which the portable terminal device 120 is mounted. Thereby, the portable terminal device 120 can receive the information received by the first antenna 111a via the signal transmission path 113 and the second antenna 111b without performing signal amplification or the like. Also, the portable terminal device 120 can transmit the information transmitted to the second antenna 111b via the signal transmission path 113 and the first antenna 111a without performing signal amplification or the like. Therefore, according to this embodiment, in the out - of - service area 102 where people do not constantly exist, such as in a sewer, the power - free wireless relay device 110 that enables communication of the portable terminal device 120 can be easily installed and operated.

[0049] Therefore, the underground work staff St2 can communicate with the outside and obtain information from the outside in the out - of - service area 102 without transmitting to the above - ground work staff St1 and without moving to the communicable area 101. Thereby, the work efficiency of the work staff St can be improved. Also, when the work staff St finishes inspecting the sewer or the like, the power - free wireless relay device 110 is put away. For this reason, in a place where people do not constantly exist, such as in a sewer, that is, in a space where the construction of a communication infrastructure cannot be expected, it is not necessary to install wireless equipment such as the wireless base station 103, that is, it is not necessary to obtain a predetermined approval (license), and unnecessary equipment investment can be suppressed, enabling communication of the portable terminal device 120.

[0050] Also, in the wireless power - free relay device 110 according to the present embodiment, the first antenna 111a and the second antenna 111b are omnidirectional antennas. Thereby, when the work staff St installs the first antenna 111a, the first antenna 111a can be installed simply and quickly without considering the directivity of the first antenna 111a. Also, when the underground work staff St2 places the portable terminal device 120 on the placement portion 114, the portable terminal device 120 can be placed without considering the directivity of the second antenna 111b.

[0051] Also, in the wireless power - free relay device 110 according to the present embodiment, the second antenna 111b is a broadband antenna. Thereby, the communication of the portable terminal device 120 can be performed efficiently.

[0052] Also, in the wireless power - free relay device 110 according to the present embodiment, the placement portion 114 is made to be able to place the portable terminal device 120 according to the shape of the second antenna 111b. Thereby, a plurality of underground work staff St2 can place the portable terminal device 120 on the placement portion 114 and use the portable terminal device 120. Therefore, the convenience can be improved.

[0053] Also, in the wireless power - free relay device 110 according to the present embodiment, the placement portion 114 is composed of a resin member. Thereby, since the placement portion 114 can be realized with a lightweight material, the carrying of the wireless power - free relay device 110 can be made easier.

[0054] Also, in the wireless power - free relay device 110 according to the present embodiment, when a communication error occurs in the portable terminal device 120, the portable terminal device 120 is configured to notify the work staff St to that effect. Thereby, since the work staff St can recognize the communication error at an early stage, the communication error can be eliminated at an early stage. In particular, in work such as inside a sewer, there is a high possibility that the underground work staff St2 will be exposed to a dangerous state and a serious accident may be caused due to the inability to obtain information from the outside. However, according to the present embodiment, such an accident can be prevented.

[0055] Also, in the power - free wireless relay device 110 according to the present embodiment, the mobile terminal device 120 gives a warning regarding danger based on the current location information, the rainfall information, and the risk degree information 500 of water inflow set for each sewer. Thereby, a warning can be given according to the risk degree of the sewer and the rainfall. Therefore, it becomes possible to evacuate and guide the underground work staff St2 working in the sewer, and the safety of the underground work staff St2 can be improved.

[0056] Supplementary explanation about the basic spirit of the Radio Law is given below. In a mobile phone system, a large number of radio base stations 103 are arranged, and complex controls such as which radio base station 103 it is most reasonable for a mobile phone to communicate with and the control when a mobile phone moves across a radio base station 103 (handover) are carried out to maintain the communication order. For this reason, the government agency in charge of radio administration (for example, the Ministry of Internal Affairs and Communications) limits the license holders of radio base stations 103 including auxiliary relay devices to communication carriers. This is the basic spirit of the orderly use of radio waves in the Radio Law. In other words, those who have not obtained permission are not allowed to install a relay device (radio base station 103). By the way, the power - free wireless relay device 110 according to the present embodiment may be strictly said to be similar to a relay device. However, since the power - free wireless relay device 110 according to the present embodiment does not affect other communications by the device, it can be said to be an "orderly use of radio waves" and is available. Note that weak radio wave radiation may be considered not to violate the "orderly use of radio waves". As an example, a product that can play FM radio waves from a music player in a microphone and listen to it on a car stereo is considered available.

[0057] Also, regarding the enlargement of the wireless power - free relay device 110, the undesirable aspects will be supplemented. In the wireless power - free relay device 110, it is possible to increase the length of the signal transmission path 113. However, in this case, in order to increase the energy captured by the first antenna 111a, it is necessary to enlarge the first antenna 111a. To give an extreme example, a large parabolic antenna used for deep - space exploration can be assumed. However, these, like sharp searchlights, perform the operation of determining a target based on their directivity and capturing weak energy. The wireless power - free relay device 110 according to the present embodiment does not communicate by determining a specific target, but aims to acquire as many radio waves as possible from a large number of radio base stations 103 and assist in making a communication - impossible area communicable according to the control by a communication carrier. Also, to increase the length of the signal transmission path 113, signal amplification by active elements in the signal transmission path 113 is required. This is a transmitter and is the relay device itself. Therefore, it is not desirable to enlarge the wireless power - free relay device 110 according to the present embodiment.

[0058] (Modification example of the embodiment) Next, a modification example of the embodiment will be described. In each of the following modification examples, the description of the content described in the above - mentioned embodiment will be omitted as appropriate. Also, each of the following modification examples and the above - mentioned embodiment can be combined with each other.

[0059] (Modification example 1) First, modification example 1 of the embodiment will be described. In the above - mentioned embodiment, one first antenna 111a was installed in the communicable area 101. In modification example 1, a configuration in which a plurality of first antennas 111a are installed in the communicable area 101 will be described. In modification example 1, for example, two first antennas 111a are installed in the communicable area 101. The two first antennas 111a are each connected to the second antenna 111b via the signal transmission path 113.

[0060] According to Modification Example 1, since the radio wave intensity can be increased according to the number of the first antennas 111a, the communication environment can be improved. That is, since the first antenna 111a is enlarged and as much energy as possible can be obtained from the space, the communication can be stabilized.

[0061] However, the wireless relay device 110 without power supply according to the present embodiment is to enable communication in a space where communication is impossible. It is an effective usage method to carry and use this small and lightweight device in a place where there is nothing like a sewer. For this reason, even when a plurality of first antennas 111a are used, it is desirable that the first antenna 111a is not enlarged as much as possible, that is, it is desirable that the portability is not impaired.

[0062] (Modification Example 2) Next, Modification Example 2 of the embodiment will be described. In Modification Example 2, a configuration for prompting a change in the specifications of the wireless relay device 110 without power supply according to the radio wave intensity when the radio wave state is weak will be described. For example, even when the portable terminal device 120 is brought close to the second antenna 111b or when there is no abnormality in the first antenna 111a, the radio wave state may be weak.

[0063] In this case, the portable terminal device 120 may notify that the signal transmission path 113 is to be changed to a lower-loss one according to the radio wave intensity. Specifically, when the radio wave intensity is slightly weak, the portable terminal device 120 prompts to change the signal transmission path 113 to a lower-loss one, and when the radio wave intensity is very weak, it prompts to change it to an even lower-loss one.

[0064] Further, the portable terminal device 120 may notify that the addition of the first antenna 111a is to be prompted according to the radio wave intensity. Specifically, when the radio wave intensity is slightly weak, the portable terminal device 120 prompts to add one first antenna 111a, and when the radio wave intensity is very weak, it may prompt to add two first antennas 111a.

[0065] According to Modification Example 2, since it is possible to encourage increasing the radio wave intensity when the radio wave state is weak, the communication environment can be improved.

[0066] (Modification Example 3) Next, Modification Example 3 of the embodiment will be described. In the above-described embodiment, a warning regarding danger is given based on the current location information, the rainfall information, and the risk degree information 500 of water inflow set for each sewer. In Modification Example 3, a configuration for giving a warning regarding danger based on the current location information and the rainfall information without using the risk degree information 500 will be described. In Modification Example 3, the portable terminal device 120 acquires the current location information of its own device and the rainfall information of the surroundings. Then, when a rain cloud approaches (or when it rains) near the current location, the portable terminal device 120 gives a warning regarding danger.

[0067] According to Modification Example 3, even if the portable terminal device 120 does not store the risk degree information 500, a warning can be given according to whether a rain cloud approaches the surroundings. For this reason, a warning can be given simply.

[0068] (Modification Example 4) Next, Modification Example 4 of the embodiment will be described. In the above-described embodiment, a warning regarding danger is given based on the current location information, the rainfall information, and the risk degree information 500 of water inflow set for each sewer. In Modification Example 4, a configuration for giving a warning regarding danger based on the detection result of a sensor provided in a manhole (manhole sensor) will be described. In Modification Example 4, the manhole sensor detects sewer information (for example, water level, water quality, flow rate, etc.). The detection result of the manhole sensor is stored in a predetermined server device. The portable terminal device 120 acquires the current location information of its own device and also acquires the sewer information detected by the surrounding manholes from the server device.

[0069] Then, the mobile terminal device 120 refers to the sewer information and issues a danger warning when the water level around the current location is rising or the flow rate around the current location is increasing. Further, the mobile terminal device 120 may calculate and present the predicted time when the sewer at the current location becomes dangerous based on the water level and flow rate of the surrounding sewers and the distance to the sewer.

[0070] According to Modification 4, a warning can be issued according to the information of the sewer around the current location. Therefore, the safety of the underground workers St2 working in the sewer can be improved.

[0071] (Modification 5) Next, Modification 5 of the embodiment will be described. In the above-described embodiment, the out-of-range area 102 is a sewer. In Modification 5, the out-of-range area 102 is a location other than a sewer. Specifically, the out-of-range area 102 is, for example, the basement of a mixed-use building, a storage tank, equipment installed underground (equipment installed underground in a drainage tank, air conditioner, boiler, and water supply pump building), etc., and is a place where the worker staff St enters and works. Even when the worker staff St works in such a place, the power-free wireless relay device 110 according to the present embodiment can be easily installed. Further, accidents of the worker staff St working in places other than sewers can be prevented.

[0072] (Modification 6) Next, Modification 6 of the embodiment will be described. In the above-described embodiment, in the determination of the quality of the radio wave state (see step S602), as an example, it has been described that the mobile terminal device 120 determines that it is good if it receives data at predetermined time intervals, and determines that it is bad if it does not receive data at predetermined time intervals. In Modification 6, in addition to or instead of such a configuration, a configuration in which a plurality of mobile terminal devices 120 transmit and receive data (for example, e-mails and short messages) to and from each other will be described.

[0073] Specifically, in Modification Example 6, it is assumed that a plurality of portable terminal devices 120 are placed on the placement unit 114. Each of the plurality of portable terminal devices 120 (paired portable terminal devices 120) can be set to turn on and off the function of transmitting and receiving data between the devices. When the function is turned on, each portable terminal device 120 sets itself as a transmission side and a reception side. The transmission-side portable terminal device 120 can set the data transmission timing, and the reception-side portable terminal device 120 can set the data reception timing. When the transmission timing arrives, the transmission-side portable terminal device 120 transmits data to the wireless base station 103 addressed to the reception-side portable terminal device 120. When the reception timing arrives, the reception-side portable terminal device 120 transmits the data transmitted from the transmission-side portable terminal device 120 via the wireless base station 103.

[0074] The reception-side portable terminal device 120 can notify a communication error. For example, the reception-side portable terminal device 120 notifies a communication error when it cannot receive data for a predetermined period or when it cannot receive data continuously for a predetermined number of times. When forming a pair between the transmission side and the reception side, a plurality of portable terminal devices may use short-range wireless communication (for example, Bluetooth: registered trademark) with each other to form a pair.

[0075] Also, the transmission side and the reception side are not limited to one device each, and may be a plurality of devices. For example, a plurality of transmission-side portable terminal devices 120 and one reception-side portable terminal device 120 may be used. Also, one transmission-side portable terminal device 120 and a plurality of reception-side portable terminal devices 120 may be used. Furthermore, a plurality of transmission-side portable terminal devices 120 and a plurality of reception-side portable terminal devices 120 may be used.

[0076] Also, a plurality of pairs may be formed and different communication carriers may be used. For example, for one pair, communication company A may be used, and for another pair, communication company B may be used.

[0077] According to Modification Example 6, communication errors can be detected quickly. As a result, the work staff St can be made to recognize communication errors quickly, so that the communication errors can be eliminated early.

[0078] (Modification Example 7) Next, Modification Example 7 of the embodiment will be described. In Modification Example 7, regarding the notification of communication errors, a configuration capable of executing a training mode (hereinafter referred to as the "training mode") will be described. The training mode is a mode in which a state where the radio wave intensity is likely to decrease is intentionally created to cause a communication error. In Modification Example 7, when starting the training mode, the mobile terminal device 120 stores the radio wave intensity in a state where no communication error has occurred. The training mode includes a first training and a second training.

[0079] In the first training, the mobile terminal device 120 issues an instruction to, for example, turn over the first antenna 111a. When the first antenna 111a is turned over, the radio wave intensity is likely to decrease. After the instruction, when the radio wave intensity reaches a non-communication level, the mobile terminal device 120 notifies of a communication error. On the other hand, when the radio base station 103 is present nearby and the radio wave intensity is still at a communicable level even though it has decreased, it notifies that no such communication error has occurred.

[0080] Also, in the second training, the mobile terminal device 120 issues an instruction to move the mobile terminal device 120 away from the second antenna 111b. After the instruction, when the radio wave intensity reaches a non-communication level, the mobile terminal device 120 notifies of a communication error.

[0081] According to Modification Example 7, by performing the training mode, it is possible to confirm whether a communication error is properly notified at the start of work or the like. Also, assuming that the communication level was at a communicable level in the first training, when a communication error occurs during normal use after the training mode, the mobile terminal device 120 can estimate that the cause of the communication error lies in the distance between the mobile terminal device 120 and the second antenna 111b and notify it. Therefore, the communication error can be resolved at an early stage.

[0082] (Modification Example 8) Next, Modification Example 8 of the embodiment will be described. In the above-described embodiment, the configuration using a broadband antenna corresponding to a frequency range of 700 MHz to 6 GHz as the antenna 111 has been described. In Modification Example 8, a configuration using a narrowband antenna as the antenna 111 will be described.

[0083] In Modification Example 8, as the antenna 111, for example, a narrowband antenna corresponding to the lowest frequency band such as the 700 MHz band is used. Generally, the manufacturing technology required for wireless communication devices becomes higher as the frequency increases. In other words, as the frequency increases, the cost increases. Therefore, by constructing the passive wireless relay device 110 focusing on the lowest 700 MHz band, it becomes cost-effective and communication becomes possible. Note that the antenna 111 can also use a narrowband antenna corresponding to a high frequency band such as the 3500 MHz band (3.5 GHz band).

[0084] According to Modification Example 8, the passive wireless relay device 110 can be installed simply and at low cost.

[0085] (Regarding the case of using a directional antenna) Next, a supplement is made regarding the case where a directional antenna is used. In the above-described embodiment, the second antenna 111b is an omnidirectional antenna. Here, let's assume that the second antenna 111b is a directional antenna. A directional antenna is an antenna whose level varies depending on the direction of the antenna. By using a directional antenna, it may be possible to increase the radio wave intensity in the second antenna 111b. However, since a directional antenna emits weak energy as a space wave, it may be technically difficult to make the second antenna 111b a directional antenna.

[0086] Also, as described above, it is also possible to make the first antenna 111a a directional antenna, and a supplement is made regarding this as well. The radio base station 103 to which the mobile terminal device 120 connects is set by a communication carrier according to the communication congestion situation and the like. For this reason, if the first antenna 111a is a directional antenna, the work staff St searches for the radio base station 103 to be connected to. Also, communication becomes possible under the control of the communication carrier side.

[0087] The functions of the mobile terminal device 120 in the above-described embodiments may be realized by a computer. In that case, a program for realizing these functions may be recorded on a computer-readable recording medium, and the program recorded on this recording medium may be read into a computer system and executed to be realized. Here, the “computer system” shall include hardware such as an OS and peripheral devices. Further, the “computer-readable recording medium” refers to a portable medium such as a flexible disk, a magneto-optical disk, a ROM, a CD-ROM, etc., and a storage device such as a hard disk built in a computer system. Furthermore, the “computer-readable recording medium” also includes, like a communication line when transmitting a program via a network such as the Internet or a communication line such as a telephone line, something that dynamically holds a program for a short time, and something that holds a program for a certain time, like a volatile memory inside a computer system that becomes a server or a client in that case. Also, the above program may be for realizing a part of the aforementioned functions, and may further be something that can be realized in combination with a program already recorded in a computer system for the aforementioned functions.

[0088] Although some embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the gist of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are also included in the invention described in the claims and its equivalent scope.

Description of Reference Numerals

[0089] 101…Communication possible area, 102…Out-of-range area, 110…Wireless relay device without power supply, 111a…First antenna, 111b…Second antenna, 113…Signal transmission path, 114…Mounting part, 120…Mobile terminal device, 401…CPU, 402…ROM, 403…RAM, 404…Memory, 405…Communication interface, 411…GPS unit

Claims

1. a portable first antenna arranged in a first area in which the mobile terminal device can communicate; a portable second antenna arranged in a second area where the mobile terminal device cannot communicate; a signal transmission path connecting the first antenna and the second antenna; a mounting portion for mounting the mobile terminal device thereon, the mounting portion being disposed adjacent to the second antenna; Equipped with The first antenna and the second antenna are broadband and omnidirectional antennas capable of communication with the mobile terminal device.

2. A non-powered wireless repeater device comprising:

2. the mounting section is capable of mounting a plurality of the mobile terminal devices in a manner corresponding to the shape of the second antenna; 2. The non-powered wireless repeater device according to claim 1 .

3. A wireless relay system including the wireless relay device according to claim 1 or 2 and the mobile terminal device, the mobile terminal device issues a warning about danger based on information about a current location, information about surrounding rainfall, and information indicating a risk of water inflow set for each sewer system, and notifies a user of a communication error if such an error occurs; A non-powered wireless relay system.

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